[Lenvatinib down-regulates IGF1R/Mek/Erk signaling pathway in the treatment of regorafenib-resistant hepatocellular carcinoma].

Objective: To investigate the therapeutic effect and mechanism of lenvatinib on regorafenib-resistant hepatocellular carcinoma cells. Methods: CCK-8 and clone formation assay were used to observe the inhibitory effect of lenvatinib on the growth of hepatocellular carcinoma cells. Flow cytometry was used to detect the apoptosis of regorafenib-resistant hepatocellular carcinoma cells treated with lenvatinib. The expression levels of related proteins were detected by western blot and immunohistochemical staining. The inhibitory effect of lenvatinib on the tumor formation ability of regorafenib-resistant hepatocellular carcinoma cells in vivo was observed by subcutaneous tumor formation experiment in mice. Results: CCK-8 and clone formation assay showed that lenvatinib could inhibit the proliferation of regorafenib-resistant hepatocellular carcinoma cells. The number of clones of HepG2, SMMC7721 and regorafenib-resistant HepG2, SMMC7721 cells in lenvatinib group (120.67±11.06, 53.00±11.14, 55.00±9.54, 78.67±14.64) were all lower than those in control group (478.00±24.52, 566.00±27.87, 333.67±7.02, 210.00±12.77, all P<0.05). Flow cytometry showed that lenvatinib could promote apoptosis of regorafenib-resistant hepatocellular carcinoma cells, the apoptosis rates of HepG2, SMMC7721 and regorafenib-resistant HepG2, SMMC7721 cells in lenvatinib group [(12.30±0.70)%, (9.83±0.38)%, (15.90±1.32)%, (10.60±0.00)%] were all higher than those in control group [(7.50±0.87)%, (5.00±1.21)%, (8.10±1.61)%, (7.05±0.78)%, all P<0.05]. The apoptosis-related protein levels suggested that apoptosis was increased in the treatment of lenvatinib. The animal study showed that lenvatinib can inhibit the growth of regorafenib-resistant cells in vivo. Immunohistochemistry and western blot results showed that lenvatinib could down-regulate the abnormally activated IGF1R/Mek/Erk signaling pathway in regorafenib-resistant cells. Conclusion: Lenvatinib can reverse regorafenib resistance in hepatocellular carcinoma, possibly by down-regulating IGF1R/Mek/Erk signaling pathway.

[Involvement of Src kinase in the down-regulation of ultra-rapid delayed rectifier K(+)current induced by tumor necrosis factor-α in cardiomyocytes].

Objective: To investigate whether inflammatory factor tumor necrosis factor-α (TNF-α) is involved in the electrical remodeling of cardiomyocytes by regulating ultra-rapid delayed rectifier K(+) current (I(kur)) and the role of Src kinase. Methods: H9c2 cells, embryonic cardiomyocytes of rat, were cultured in Dulbecco's modified Eagle's medium (DMEM) and atrium-derived HL-1 cells were cultured in Claycomb medium. Both H9c2 and HL-1 cells were cultured at 37 ℃ with 5% CO(2). Cells cultured in normal conditions without additional treatment served as control group. Experimental groups were treated with different concentration of TNF-α (25 or 50 or 100 ng/ml) for 24 hours. To study whether Src specific inhibitor PP1 could abrogate the effect of TNF-α, cells were pre-treated with 10 µmol/L PP1 for 1 hour, followed by TNF-α (100 ng/ml) for 24 hours. Western blot and the whole cell patch clamp technique were used to detect the protein expression of Kv1.5 and Src and I(kur) in each group. Results: (1) In H9c2 cells, high concentration of TNF-α treatment (100 ng/ml) significantly reduced the Kv1.5 protein expression compared with control group and TNF-α 25 ng/ml group (both P<0.05). Compared with control group, the expression of p-Src protein was higher in 25 ng/ml, 50 ng/ml, 100 ng/ml TNF-α group (all P<0.05), but there was no statistical difference in the expression of Src protein among groups (P>0.05). In addition, the current density of I(kur) was decreased in 50 ng/ml, 100 ng/ml TNF-α group (both P<0.05). Furthermore, the expression of Kv1.5 protein and the current density of I(kur) were increased in PP1+TNF-α group compared with TNF-α 100 ng/ml group (both P<0.05). There was no statistical difference in the expression of Kv1.5 protein and the current density of I(kur) between the control group and PP1+TNF-α group (both P>0.05). (2) In atrium-derived HL-1 cells, the expression of Kv1.5 protein was reduced in 100 ng/ml TNF-α group compared with control group and TNF-α 25 ng/ml group (both P<0.01). In addition, the expression of p-Src protein was increased in TNF-α 100 ng/ml group compared with control group (P<0.05), but there was no statistical difference in the protein expression of Src among groups (P>0.05). The expression of Kv1.5 protein was increased in PP1+TNF-α group compared with TNF-α 100 ng/ml group (P<0.05). Conclusion: TNF-α is involved in the pathogenesis of atrial fibrillation, probably via decreasing I(kur) current density in atrium-derived myocytes through the activation of Src kinase.

Effect of high-fat diet on secreted milk transcriptome in midlactation mice.

High-fat diet (HFD) during lactation alters milk composition and is associated with development of metabolic diseases in the offspring. We hypothesized that HFD affects milk microRNA (miRNA) and mRNA content, which potentially impact offspring development. Our objective was to determine the effect of maternal HFD on secreted milk transcriptome. To meet this objective, 4 wk old female ICR mice were divided into two treatments: control diet containing 10% kcal fat and HFD containing 60% kcal fat. After 4 wk on CD or HFD, mice were bred while continuously fed the same diets. On postnatal day 2 (P2), litters were normalized to 10 pups, and half the pups in each litter were cross-fostered between treatments. Milk was collected from dams on P10 and P12. Total RNA was isolated from milk fat fraction of P10 samples and used for mRNA-Seq and small RNA-Seq. P12 milk was used to determine macronutrient composition. After 4 wk of prepregnancy feeding HFD mice weighed significantly more than did the control mice. Lactose and fat concentration were significantly ( P < 0.05) higher in milk of HFD dams. Pup weight was significantly greater ( P < 0.05) in groups suckled by HFD vs. control dams. There were 25 miRNA and over 1,500 mRNA differentially expressed (DE) in milk of HFD vs. control dams. DE mRNA and target genes of DE miRNA enriched categories that were primarily related to multicellular organismal development. Maternal HFD impacts mRNA and miRNA content of milk, if bioactive nucleic acids are absorbed by neonate differences may affect development.

[First aid system for trauma: development and status].

With the great progress of the economy, the level of industrialization has been increasing year by year, which leads to an increase in accidental trauma accidents. Chinese annual death of trauma is already more than 400 000, which makes trauma the fifth most common cause of death, following malignant tumor, heart, brain and respiratory diseases. Trauma is the leading cause of the death of young adults. At the same time, trauma has become a serious social problem in peace time. Trauma throws great treats on human health and life. As an important part in the medical and social security system, the emergency of trauma system occupies a very important position in the emergency medical service system. In European countries as well as the United States and also many other developed countries, trauma service system had a long history, and progressed to an advanced stage. However, Chinese trauma service system started late and is still developing. It has not turned into a complete and standardized system yet. This review summarizes the histories and current situations of the development of traumatic first aid system separately in European countries, the United States and our country. Special attentions are paid to the effects of the pre- and in-hospital emergency care. We also further try to explore the Chinese trauma emergency model that adapts to the situations of China and characteristics of different regions of China. Our review also introduces the trauma service system that suits the situations of China proposed by Professor Jiang Baoguo's team in details, taking Chinese conditions into account, they conducted a thematic study and made an expert consensus on pre-hospital emergency treatment of severe trauma, providing a basic routine and guidance of severe trauma treatment for those pre-hospital emergency physicians. They also advised to establish independent trauma disciplines and trauma specialist training systems, and to build the regional trauma care system as well as the standards for graded treatment, thus establishing a multiple disciplinary team (MDT) of severe trauma. In this way, we can reduce the mortality and disability risks of severe trauma, improve the quality of patients' life, and save more lives.

[Epidemiologic features of hand-foot-mouth disease in Haikou city from 2008 to 2015].

Objective: To analyze the epidemiologic features of hand-foot-mouth disease (HFMD) in Haikou city from 2008 to 2015. Methods: Descriptive methods on epidemiology and detection on pathogens were conducted in Haikou city from 2008 to 2015. Results: A total of 71 611 patients were diagnosed as HFMD in Haikou city from 2008 to 2015, including 728 severe cases, accounting for 1.02% among all the cases. The average annual incidence was 458.89/100 000. A total of 11 deaths were caused by the disease, with the average annual mortality rate as 0.07/100 000. Two peaks of incidence were seen, from April to July and from September to November. Age of the patients mainly fell in children aged 5 and below, taking up 95.78% of the total cases. Among all the patients, 1-year-olds presented the highest incidence as 12 881.24/100 000. The reported incidence for males was higher than that in females. There were 4 districts in Haikou city that reported the disease. Residential areas of the patients were scattered around, with a percentage of 79.89%. Spectrums of pathogens that causing the prevalence of HFMD were EV71 type, Cox A16 type and other enteroviruses, which prevailing in turns, since 2011. Conclusions: Haikou city had been an area with high incidence of HFMD. The incidence started to show a rising trend recently. It is suggested that programs as surveillance, case management, health education and comprehensive prevention and control of disease on HFMD targeting on key population should be intensively implemented to reduce the mortality of the disease.

An extracellular matrix culture system for induced pluripotent stem cells derived from human dental pulp cells.

OBJECTIVE: Induced pluripotent stem cells (iPSCs) have emerged as a promising tool for treating incurable diseases. The current challenges are to avoid potential xenopathogenic transmission and immune rejection potentially caused by exposure of iPSCs to animal-derived products. In addition, an efficient feeder cell-free culture condition will be required for minimizing batch-to-batch variation and facilitating scale-up. Therefore, establishing an efficient extracellular matrix (ECM) culture system is considered as a prerequisite for the future clinical application of iPSC-based cell therapies. In this study, we evaluated the feasibility of culturing iPSCs in ECM derived from human dental pulp cells (hDCP). MATERIALS AND METHODS: iPSCs growing in Matrigel were transferred to ECM or Matrigel and cultured in mTeSRTM1 medium. RESULTS: The number of adherent cells in the ECM group was higher than that in the Matrigel group after incubation for 8, 12, and 24 h, indicating that the ECM could enhance cell adherence. The adhesion of cells to ECM not only depends on simple physical attachment with ECM, but also mediated by fibronectin in the ECM. The hDPC-iPSCs showed orderly growth in the ECM, suggesting that the ECM could promote the growth and proliferation of hDPC-iPSCs. We also observed that stem cells growed along to avoid contact inhibition. CONCLUSIONS: The iPSCs maintained undifferentiated state when cultured in ECM when the iPSCs and ECM are of the same cell origin. ECM and mTeSRTM1, can both be used as new culture medium for iPSCs that facilitates the clinical application of iPSC-based cell therapies in the future.

DNA methylation of membrane-bound tyrosine phosphatase genes in acute lymphoblastic leukaemia.

Aberrant DNA promoter methylation with associated gene silencing is a common epigenetic abnormality in acute lymphoblastic leukaemia (ALL) and is associated with poor survival. We have identified a family of transmembrane tyrosine phosphatase proteins as targets of hypermethylation in ALL and high-grade B cell lymphoma and demonstrated that this abnormal methylation correlates with transcript expression. PTPRG was methylated in 63% of ALL samples, PTPRK in 47%, PTPRM in 64% and PTPRO in 54% of cases, with most ALL samples containing methylation at multiple phosphatase loci. PTPRK promoter methylation was associated with a decreased overall survival in the cohort. Restoration of PTPRK transcript levels in leukaemia cells, where phosphatase transcript was silenced, reduced cell proliferation, inhibited colony formation and increased sensitivity to cytotoxic chemotherapy. These biological changes were associated with a reduction in levels of phosphorylated Erk1/2, Akt, STAT3 and STAT5 suggesting functional phosphatase activity after transcript re-expression. Methylation of the phosphatase promoters was reversible with decitabine and a histone deacetylase inhibitor, suggesting that PTPRK-mediated cell signalling pathways may be targeted with epigenetic therapies in lymphoid malignancy.

Involvement of Src tyrosine kinase and protein kinase C in the expression of macrophage migration inhibitory factor induced by H2O2 in HL-1 mouse cardiac muscle cells.

Macrophage migration inhibitory factor (MIF), a pleiotropic cytokine, plays an important role in the pathogenesis of atrial fibrillation; however, the upstream regulation of MIF in atrial myocytes remains unclear. In the present study, we investigated whether and how MIF is regulated in response to the renin-angiotensin system and oxidative stress in atrium myocytes (HL-1 cells). MIF protein and mRNA levels in HL-1 cells were assayed using immunofluorescence, real-time PCR, and Western blot. The result indicated that MIF was expressed in the cytoplasm of HL-1 cells. Hydrogen peroxide (H2O2), but not angiotensin II, stimulated MIF expression in HL-1 cells. H2O2-induced MIF protein and gene levels increased in a dose-dependent manner and were completely abolished in the presence of catalase. H2O2-induced MIF production was completely inhibited by tyrosine kinase inhibitors genistein and PP1, as well as by protein kinase C (PKC) inhibitor GF109203X, suggesting that redox-sensitive MIF production is mediated through tyrosine kinase and PKC-dependent mechanisms in HL-1 cells. These results suggest that MIF is upregulated by HL-1 cells in response to redox stress, probably by the activation of Src and PKC.

Effects of dietary copper on growth, digestive, and brush border enzyme activities and antioxidant defense of hepatopancreas and intestine for young grass carp (Ctenopharyngodon idella).

To investigate the effects of dietary copper (Cu) on fish growth, digestive and absorptive enzyme activities, and antioxidant status in the hepatopancreas and intestine, young grass carp (Ctenopharyngodon idella) (282±2.8 g) were fed six diets containing 0.74 (basal diet), 2.26, 3.75, 5.25, 6.70, and 8.33 mg Cu /kg diet for 8 weeks. Results showed that percentage weight gain (PWG) and feed intake were increased with dietary Cu levels up to 3.75 mg/kg diet. In addition, the positive effects of dietary Cu at a level 3.75 or 5.25 mg/kg diet on trypsin, chymotrypsin, and lipase activities in the hepatopancreas and of Na(+), K(+)-ATPase, alkaline phosphatase, creatine kinase, and γ-glutamyl transpeptidase activities in three intestine segments produced significantly (P<0.05) better feed efficiency (FE). However, amylase activity in the hepatopancreas was decreased by dietary Cu levels up to 3.75 mg/kg diet (P<0.05). In addition, dietary Cu at 3.75 or 5.25 mg/kg diet decreased malondialdehyde and protein carbonyl content partly by significantly (P<0.05) increasing the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione-S-transferase, and glutathione content in the hepatopancreas and intestine. Collectively, dietary Cu improved growth and digestive and absorptive capacity and decreased lipid peroxidation and protein oxidation partly by enhancing antioxidant defense in the hepatopancreas and intestine. The dietary Cu requirement for PWG, plasma ceruloplasmin activity, and FE of young grass carp (282-688 g) were 4.78, 4.95, and 4.70 mg/kg diet, respectively.

Involvement of Src tyrosine kinase and protein kinase C in the expression of macrophage migration inhibitory factor induced by H2O2 in HL-1 mouse cardiac muscle cells

Macrophage migration inhibitory factor (MIF), a pleiotropic cytokine, plays an important role in the pathogenesis of atrial fibrillation; however, the upstream regulation of MIF in atrial myocytes remains unclear. In the present study, we investigated whether and how MIF is regulated in response to the renin-angiotensin system and oxidative stress in atrium myocytes (HL-1 cells). MIF protein and mRNA levels in HL-1 cells were assayed using immunofluorescence, real-time PCR, and Western blot. The result indicated that MIF was expressed in the cytoplasm of HL-1 cells. Hydrogen peroxide (H2O2), but not angiotensin II, stimulated MIF expression in HL-1 cells. H2O2-induced MIF protein and gene levels increased in a dose-dependent manner and were completely abolished in the presence of catalase. H2O2-induced MIF production was completely inhibited by tyrosine kinase inhibitors genistein and PP1, as well as by protein kinase C (PKC) inhibitor GF109203X, suggesting that redox-sensitive MIF production is mediated through tyrosine kinase and PKC-dependent mechanisms in HL-1 cells. These results suggest that MIF is upregulated by HL-1 cells in response to redox stress, probably by the activation of Src and PKC.

Porcine satellite cells are restricted to a phenotype resembling their muscle origin.

Muscles in most domestic animals differ in function and growth potential based largely on muscle fiber type composition. Though much is known about satellite cells (SC), information is limited regarding how populations of SC differ with muscle fiber type, especially in pigs. Therefore, the objective of this study was to isolate and culture SC from red (RST) and white (WST) portions of the semitendinosus muscle of neonatal and adult pigs and determine their capacity to proliferate, differentiate, and express various myosin heavy chain (MyHC) isoforms in vitro. Porcine satellite cells were isolated from RST and WST muscles of 6-wk-old and adult (>6-mo-old) pigs and cultured under standard conditions. Muscle from neonatal pigs yielded nearly 10 times more (P < 0.001) presumptive satellite cells as those from adult pigs, with fusion percentages close to 60% for the former. The RST yielded more (P < 0.001) SC per gram muscle compared to WST, 8.1 ± 0.2 × 10(4) cells versus 6.7 ± 0.1 × 10(4) cells/gram muscle in young pigs, and 9.7 ± 0.4 × 10(3) cells versus 5.5 ± 0.4 × 10(3) cells/gram muscle in adult pigs, respectively. Likewise, satellite cells from RST proliferated faster (P < 0.001) than those from WST across both ages, as indicated by a shorter cell doubling time, 18.6 ± 0.8 h versus 21.3 ± 0.9 h in young pigs, and 23.2 ± 0.7 h versus 26.7 ± 0.9 h in adult pigs, respectively. As a result of shorter times to confluence, satellite cells from RST also formed myotubes earlier than those SC originating from WST. Once induced, however, SC from WST differentiated and fused faster (P < 0.05) as evidenced by fusion percentage within the first 24 h, 41.6% versus 34.3%, respectively; but reached similar ultimate fusion percentages similar to WST by 48 h. Over 90% of MyHC expressed in maximally fused SC cultures from both RST and WST was restricted to the embryonic isoform. Type IIX MyHC mRNA was not detected in any culture. Myotube cultures from RST expressed more (P < 0.01) Type I MyHC isoform mRNA than those from WST, whereas those cultures from WST expressed more (P < 0.05) Type II (including Types IIA and IIB) MyHC transcripts. These data show SC cultures from porcine fast and slow muscles express MyHC profiles largely reflective of their muscle of origin and suggest satellite cells are partially restricted to a particular muscle phenotype in which they are juxtapositioned. Understanding the molecular nature of these intrinsic control mechanisms may lead to improved strategies for augmenting meat animal growth or muscle regeneration.

New agents in the arsenal to fight castrate-resistant prostate cancer.

Prior to 2010, the treatment options for castrate-resistant prostate cancer (CRPC) were limited. In the past 3 years, four new agents have been approved by the US Food and Drug Administration for use in CRPC. These four agents differ in their mechanisms of action and highlight the progress made in our understanding of CRPC, and more importantly, provide options with proven clinical benefit. This review examines the development, investigational evolution, adverse events, and future direction of: 1) the androgen receptor inhibitor, enzalutamide, 2) androgen biosynthesis inhibitor, abiraterone, 3) novel taxane chemotherapy, cabazitaxel, and 4) autologous immunotherapeutic agent, sipuleucel-T.

Detection of bladder cancer using proteomic profiling of urine sediments.

We used protein expression profiles to develop a classification rule for the detection and prognostic assessment of bladder cancer in voided urine samples. Using the Ciphergen PBS II ProteinChip Reader, we analyzed the protein profiles of 18 pairs of samples of bladder tumor and adjacent urothelium tissue, a training set of 85 voided urine samples (32 controls and 53 bladder cancer), and a blinded testing set of 68 voided urine samples (33 controls and 35 bladder cancer). Using t-tests, we identified 473 peaks showing significant differential expression across different categories of paired bladder tumor and adjacent urothelial samples compared to normal urothelium. Then the intensities of those 473 peaks were examined in a training set of voided urine samples. Using this approach, we identified 41 protein peaks that were differentially expressed in both sets of samples. The expression pattern of the 41 protein peaks was used to classify the voided urine samples as malignant or benign. This approach yielded a sensitivity and specificity of 59% and 90%, respectively, on the training set and 80% and 100%, respectively, on the testing set. The proteomic classification rule performed with similar accuracy in low- and high-grade bladder carcinomas. In addition, we used hierarchical clustering with all 473 protein peaks on 65 benign voided urine samples, 88 samples from patients with clinically evident bladder cancer, and 127 samples from patients with a history of bladder cancer to classify the samples into Cluster A or B. The tumors in Cluster B were characterized by clinically aggressive behavior with significantly shorter metastasis-free and disease-specific survival.

Rapid salivary pepsin test: blinded assessment of test performance in gastroesophageal reflux disease.

OBJECTIVE/HYPOTHESIS: Pepsin lateral flow device (LFD) is a rapid noninvasive test to detect salivary pepsin as a surrogate marker for gastroesophageal reflux disease (GERD). We aimed to establish the test sensitivity, specificity, positive and negative predictive values (PPV, NPV) in patients with symptomatic and objective evidence of GERD compared to healthy controls. STUDY DESIGN: Prospective, blinded, controlled cohort study. METHODS: A total of 230 samples were analyzed. In vitro bench testing was conducted on 52 gastric juice and 54 sterile water samples to assess test sensitivity and specificity. Saliva was collected from 58 patients with GERD and 51 controls. All patients with GERD underwent esophagogastroduodenoscopy (EGD) and wireless 48-hour pH monitoring off acid suppressive therapy. PPV and NPV were calculated based on disease definition of esophagitis and/or abnormal pH monitoring. RESULTS: Receiver operating characteristics analysis of in vitro samples found assay sensitivity and a specificity of 87%. There were 6/51 (12%) control subjects and 13/58 (22%) patients with GERD who tested positive for salivary pepsin (P = .25). There was a step-wise increase in the prevalence of positive salivary pepsin: esophagitis (55%), abnormal pH monitoring (43%), GERD symptoms only (24%) (P < .001). Salivary pepsin test showed a PPV of 81% and NPV of 78% for those with objective evidence of GERD (abnormal pH and/or esophagitis). CONCLUSIONS: Rapid LFD for salivary pepsin has acceptable test characteristics in patients with GERD. A positive salivary pepsin test in this group may obviate the need for more expensive diagnostic testing by EGD or pH monitoring.

Targeted cyst wall puncture and aspiration during EUS-FNA increases the diagnostic yield of premalignant and malignant pancreatic cysts.

BACKGROUND: Characterization of pancreatic cysts by using EUS-FNA includes chemical and cytologic analysis. OBJECTIVE: To evaluate whether material obtained from FNA of the cyst wall increases diagnostic yield. DESIGN: Prospective series. SETTING: Tertiary referral center. PATIENTS: Consecutive patients with pancreatic cysts referred for EUS-FNA between March 2010 and March 2011. INTERVENTION: FNA was performed with aspiration of cyst fluid for carcinoembryonic antigen (CEA) and cytology, followed by cyst wall puncture (CWP). CWP is defined as puncturing the far wall of the cyst and moving the needle back and forth through the wall to sample the wall epithelium. MAIN OUTCOME MEASUREMENTS: The diagnostic yield for mucinous cystic pancreatic neoplasms by CEA and cytology obtained from cyst fluid compared with cytology obtained from CWP. CEA ≥192 ng/mL was considered mucinous. RESULTS: A total of 69 pancreatic cysts from 66 patients were included. Adequate amounts of fluid were aspirated for CEA, amylase, and cytology in 60 cysts (81%). Cellular material adequate for cytologic assessment from CWP was obtained in 56 cysts (81%). Ten (30%) of 33 cysts with CEA <192 ng/mL and negative results of cyst fluid cytology had a mucinous diagnosis from CWP; 6 of 9 (67%) cysts with an insufficient amount of fluid for CEA analysis and cyst fluid cytology had a mucinous diagnosis from CWP. Furthermore, 4 malignant cysts were independently diagnosed by CWP cytology. The incremental diagnostic yield of CWP for mucinous or malignant cysts was therefore 29% (20 of 69 cysts, P = .0001). An episode of pancreatitis (1.45%) occurred. LIMITATION: Lack of surgical criterion standard. CONCLUSIONS: CWP during EUS-FNA is a safe and effective technique for improving the diagnostic yield for premalignant and malignant pancreatic cysts.

Meat Science and Muscle Biology Symposium: stem cell niche and postnatal muscle growth.

Stem cell niche plays a critical role in regulating the behavior and function of adult stem cells that underlie tissue growth, maintenance, and regeneration. In the skeletal muscle, stem cells, called satellite cells, contribute to postnatal muscle growth and hypertrophy, and thus, meat production in agricultural animals. Satellite cells are located adjacent to mature muscle fibers underneath a sheath of basal lamina. Microenvironmental signals from extracellular matrix mediated by the basal lamina and from the host myofiber both impinge on satellite cells to regulate their activity. Furthermore, several types of muscle interstitial cells, including intramuscular preadipocytes and connective tissue fibroblasts, have recently been shown to interact with satellite cells and actively regulate the growth and regeneration of postnatal skeletal muscles. From this regard, interstitial adipogenic cells are not only important for marbling and meat quality, but also represent an additional cellular component of the satellite cell niche. At the molecular level, these interstitial cells may interact with satellite cells through cell surface ligands, such as delta-like 1 homolog (Dlk1) protein whose overexpression is thought to be responsible for muscle hypertrophy in callipyge sheep. In fact, extracellular Dlk1 protein has been shown to promote the myogenic differentiation of satellite cells. Understanding the cellular and molecular mechanisms within the stem cell niche that regulate satellite cell differentiation and maintain muscle homeostasis may lead to promising approaches to optimizing muscle growth and composition, thus improving meat production and quality.

Relationship of pancreatic mass size and diagnostic yield of endoscopic ultrasound-guided fine needle aspiration.

BACKGROUND: Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is central to discerning the diagnosis of solid pancreatic tumors through tissue acquisition. Test performance is affected by a number of factors including location of mass within the pancreas, presence of onsite cytology technologist, and number of passes with the needle. The influence of tumor size has not been well studied. AIM: The objective of the current study was to determine whether the size of mass affects the diagnostic accuracy for solid pancreatic lesions aspirated under EUS guidance. METHODS: Data were collected retrospectively on all patients with solid pancreatic masses undergoing EUS-FNA from June 2003 to August 2010. The cytology samples were reported as positive, suspicious for malignancy, atypical, negative, or nondiagnostic. The gold standard for a cytological diagnosis was histological confirmation or clinical follow-up of more than 6 months with repeat imaging. Patients were divided into five groups based upon lesion size as follows: (a) less than 1 cm, (b) 1-2 cm, (c) 2-3 cm, (d) 3-4 cm, and (e) greater than 4 cm. Performance characteristics of EUS-FNA including sensitivity, specificity, and accuracy were compared for each group. Accuracy was defined as the ratio of the sum of true-positive and true-negative values divided by the number of lesions. RESULTS: We identified 583 patients with solid pancreatic lesions in which EUS-FNA was performed and adequate cellularity was obtained (47% men, mean age 65 ± 1.4 (SE) years). Overall, 486 (83%) of lesions were pancreatic adenocarcinoma, 18 (3%) were neuroendocrine tumors, 12 (2%) were lymphomas, and 67 (12%) were benign lesions. The median size of the mass was 3 cm (range, 0.5-7 cm). A mean of 4.9 passes (range, 1-9 passes) was needed to obtain adequate samples from lesions. The overall yield of obtaining adequate samples for diagnosis was 85%. When stratified by size, the EUS-FNA sensitivity for lesions with size <1, 1-2, 2-3, 3-4, and >4 cm was 40, 75.9, 86.9, 93.2, and 91.6%, respectively; EUS-FNA sensitivity strongly correlate with tumor size (p < 0.001). Similarly, the accuracy of EUS-FNA increased as lesion size increased, ranging from 47% for tumors less than 1 cm to 88% for tumors greater than 4 cm (p < 0.05). Location of tumor and number of needle passes did not significantly influence EUS-FNA performance characteristics. CONCLUSIONS: The sensitivity and diagnostic accuracy of EUS-FNA for solid pancreatic lesions is strongly correlated with tumor size. Sensitivity and accuracy decrease significantly for tumors that are smaller than 1 cm.

Microencapsulation as a tool for incorporating bioactive ingredients into food.

Microencapsulation has been developed by the pharmaceutical industry as a means to control or modify the release of drug substances from drug delivery systems. In drug delivery systems microencapsulation is used to improve the bioavailability of drugs, control drug release kinetics, minimize drug side effects, and mask the bitter taste of drug substances. The application of microencapsulation has been extended to the food industry, typically for controlling the release of flavorings and the production of foods containing functional ingredients (e.g. probiotics and bioactive ingredients). Compared to the pharmaceutical industry, the food industry has lower profit margins and therefore the criteria in selecting a suitable microencapsulation technology are more stringent. The type of microcapsule (reservoir and matrix systems) produced and its resultant release properties are dependent on the microencapsulation technology, in addition to the physicochemical properties of the core and the shell materials. This review discusses the factors that affect the release of bioactive ingredients from microcapsules produced by different microencapsulation technologies. The key criteria in selecting a suitable microencapsulation technology are also discussed. Two of the most common physical microencapsulation technologies used in pharmaceutical processing, fluidized-bed coating, and extrusion-spheronization are explained to highlight how they might be adapted to the microencapsulation of functional bioactive ingredients in the food industry.

Increased expression and cellular localization of spermine oxidase in ulcerative colitis and relationship to disease activity.

BACKGROUND: Polyamines are important in cell growth and wound repair, but have also been implicated in inflammation-induced carcinogenesis. Polyamine metabolism includes back-conversion of spermine to spermidine by the enzyme spermine oxidase (SMO), which produces hydrogen peroxide that causes oxidative stress. In ulcerative colitis (UC), levels of spermine are decreased compared to spermidine. Therefore, we sought to determine if SMO is involved in UC. METHODS: Colon biopsies and clinical information from subjects undergoing colonoscopy for evaluation of UC or colorectal cancer screening were utilized from 16 normal controls and 53 UC cases. Histopathologic disease severity was graded and the Mayo Disease Activity Index (DAI) and endoscopy subscore assessed. SMO mRNA expression was measured in frozen biopsies by TaqMan-based real-time polymerase chain reaction (PCR). Formalin-fixed tissues were used for SMO immunohistochemistry. RESULTS: There was a 3.1-fold upregulation of SMO mRNA levels in UC patients compared to controls (P = 0.044), and a 3.7-fold increase in involved left colon versus paired uninvolved right colon (P < 0.001). With worsening histologic injury in UC there was a progressive increase in SMO staining of mononuclear inflammatory cells. There was a similar increase in SMO staining with worsening endoscopic disease severity and strong correlation with the DAI (r = 0.653, P < 0.001). Inflammatory cell SMO staining was increased in involved left colon versus uninvolved right colon. CONCLUSIONS: SMO expression is upregulated in UC tissues, deriving from increased levels in mononuclear inflammatory cells. Dysregulated polyamine homeostasis may contribute to chronic UC by altering immune responses and increasing oxidative stress.

miR-146a induces differentiation of periodontal ligament cells.

Differentiation of periodontal ligament (PDL) cells occurs under specific induction; furthermore, NF-kappaB signaling is important for regulation of bone differentiation. MicroRNAs are small non-coding RNAs that repress the translation of target genes and modulate cellular processes. miR-146a has been reported to modulate NF-kappaB signaling. This study hypothesized that miR-146a has a regulatory role in PDL differentiation by affecting NF-kappaB signaling. Immortalized PDL (I-PDL) cell lines were established by exogenous telomerase expression. The genesis of alkaline phosphatase and the up-regulation of miR-146a were induced by ascorbic acid in the I-PDL cells and primary PDL cells. I-PDL cells with exogenous miR-146a expression showed attenuation of NF-kappaB activity and exhibited higher differentiation relative to the controls. Exogenous NF-kappaB expression decreased the expression of differentiation markers, while the inactivation of endogenous NF-kappaB increased alkaline phosphatase in I-PDL cells. This study concludes that miR-146a promotes the differentiation in PDL cells through the down-regulation of NF-kappaB signaling.