Cholestasis is frequently related to endotoxemia and inflammatory response. Our previous investigation revealed a significant increase in plasma endotoxin and CD14 levels during biliary atresia. We therefore propose that lipopolysacharides (LPS) may stimulate CD14 production in liver cells and promote the removal of endotoxins. The aims of this study are to test the hypothesis that CD14 is upregulated by LPS and investigate the pathophysiological role of CD14 production during cholestasis. Using Western blotting, qRT-PCR, and promoter activity assay, we demonstrated that LPS was associated with a significant increase in CD14 and MD2 protein and mRNA expression and CD14 promoter activity in C9 rat hepatocytes but not in the HSC-T6 hepatic stellate cell line in vitro. To correlate CD14 expression and endotoxin sensitivity, in vivo biliary LPS administration was performed on rats two weeks after they were subjected to bile duct ligation (BDL) or a sham operation. CD14 expression and endotoxin levels were found to significantly increase after LPS administration in BDL rats. These returned to basal levels after 24 h. In contrast, although endotoxin levels were increased in sham-operated rats given LPS, no increase in CD14 expression was observed. However, mortality within 24 h was more frequent in the BDL animals than in the sham-operated group. In conclusion, cholestasis and LPS stimulation were here found to upregulate hepatic CD14 expression, which may have led to increased endotoxin sensitivity and host proinflammatory reactions, causing organ failure and death in BDL rats.

The generation of regulatory T (T(Reg)) cells in the thymus is crucial for immune homeostasis and self-tolerance. Recent discoveries have revealed the cellular and molecular mechanisms that govern the differentiation of a subset of developing thymocytes into natural T(Reg) cells. Several models, centred on the self-reactivity of the T cell receptor (TCR), have been proposed to explain the generation of a T(Reg) cell population that is cognizant of self. Several molecular pathways link TCR and cytokine signalling with the expression of the T(Reg) cell-associated transcription factor forkhead box P3 (FOXP3). Moreover, interplay between thymocytes and thymic antigen-presenting cells is also involved in T(Reg) cell generation.

PURPOSE: Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of immunosuppressive cells that are upregulated in cancer. Little is known about the prevalence and importance of MDSC in pancreas adenocarcinoma (PA). EXPERIMENTAL DESIGN: Peripheral blood, bone marrow, and tumor samples were collected from pancreatic cancer patients, analyzed for MDSC (CD15(+)CD11b(+)) by flow cytometry and compared to cancer-free controls. The suppressive capacity of MDSC (CD11b(+)Gr-1(+)) and the effectiveness of MDSC depletion were assessed in C57BL/6 mice inoculated with Pan02, a murine PA, and treated with placebo or zoledronic acid, a potent aminobisphosphonate previously shown to target MDSC. The tumor microenvironment was analyzed for MDSC (Gr1(+)CD11b(+)), effector T cells, and tumor cytokine levels. RESULTS: Patients with PA demonstrated increased frequency of MDSC in the bone marrow and peripheral circulation which correlated with disease stage. Normal pancreas tissue showed no MDSC infiltrate, while human tumors avidly recruited MDSC. Murine tumors similarly recruited MDSC that suppressed CD8(+) T cells in vitro and accelerated tumor growth in vivo. Treatment with zoledronic acid impaired intratumoral MDSC accumulation resulting in delayed tumor growth rate, prolonged median survival, and increased recruitment of T cells to the tumor. This was associated with a more robust type 1 response with increased levels of IFN-γ and decreased levels of IL-10. CONCLUSIONS: MDSC are important mediators of tumor-induced immunosuppression in pancreatic cancer. Inhibiting MDSC accumulation with zoledronic acid improves the host anti-tumor response in animal studies suggesting that efforts to block MDSC may represent a novel treatment strategy for pancreatic cancer.

ABSTRACT: Cirrhosis increases the risk of kidney injury and sepsis, leading to increased mortality. Elevated plasma asymmetric dimethylarginine (ADMA) occur in patients critically ill with cirrhosis, renal failure, and sepsis. We used a rat model of cirrhosis with superimposed sepsis to assess the relationship of plasma and tissue ADMA profiles with acute kidney injury and survival. 17 day-old male Sprague-Dawley rats (n = 37) were randomly assigned to four groups:(i) sham operation plus diet control (n = 6);(ii) bile duct ligation (BDL, n = 8),(iii) sham-operation plus lipopolysaccharide (LPS, n = 9), and (iv) BDL plus LPS (n = 14). LPS was given by intraperitoneal injection (1 mg/kg in saline) 3 h before sacrifice. All rats were sacrificed 14 daysintraperitoneal injection (1 mg/kg in saline) 3 h before sacrifice. All rats were sacrificed 14 days kidneys. These results were supported by the increased plasma ADMA and a decreased L arginine/ ADMA ratio (AAR). Plasma and tissue ADMA and AAR were not correlated. LPSrestored BDL-induced ADMA elevation in the liver but increased ADMA in the kidneys. LPS increased hepatic AAR and decreased renal AAR, and paradoxically increased expression of nNOSβ in the liver and kidneys. A novel mechanism underlies LPS-mediated Larginine/ ADMA/NO pathway activation and exacerbation of kidney injury and mortality in our BDL model. In the presence of cirrhosis with superimposed sepsis, simultaneous lowering of ADMA levels and enhancement of L-arginine levels to restore plasma and renal AARs may be an optimal strategy for treatment of kidney injury.

The development of regulatory T (Treg) cells is essential for the maintenance of immune tolerance and homeostasis. Here, we review recent studies that have advanced our understanding of Treg cell differentiation. In the thymus, TCR specificity to self-antigen appears to be a primary determinant for Treg cell lineage commitment, with c-Rel being an important factor that links T cell receptor (TCR) engagement and Foxp3 expression, along with cytokines and costimulatory molecules. It is also clear that postthymic events shape the peripheral Treg cell population. This includes preferential maintenance of Treg cells specific to self-antigens presented in the periphery, as well as the de novo generation of Treg cells from conventional Foxp3(-) T cells. The process of peripheral Treg cell differentiation shares some features with thymic Treg cell development, but there are notable differences. Together, thymic and peripheral Treg cell differentiation appear to generate an "imprint" of both self- and foreign antigens in the peripheral Treg cell population to provide dominant tolerance.

We report the real-time measurement of the ultrafast reorientational motion of water molecules at the water-air interface, using femtosecond time- and polarization-resolved vibrational sum-frequency spectroscopy. Vibrational excitation of dangling OH bonds along a specific polarization axis induces a transient anisotropy that decays due to the reorientation of vibrationally excited OH groups. The reorientation of interfacial water is shown to occur on subpicosecond time scales, several times faster than in the bulk, which can be attributed to the lower degree of hydrogen bond coordination at the interface. Molecular dynamics simulations of interfacial water dynamics are in quantitative agreement with experimental observations and show that, unlike in bulk, the interfacial reorientation occurs in a largely diffusive manner.

The instruction of the immune system to be tolerant of self, thereby preventing autoimmunity, is facilitated by the education of T cells in a specialized organ, the thymus, in which self-reactive cells are either eliminated or differentiated into tolerogenic Foxp3(+) regulatory T (T(reg)) cells. However, it is unknown whether T cells are also educated to be tolerant of foreign antigens, such as those from commensal bacteria, to prevent immunopathology such as inflammatory bowel disease. Here we show that encounter with commensal microbiota results in the peripheral generation of T(reg) cells rather than pathogenic effectors. We observed that colonic T(reg) cells used T-cell antigen receptors (TCRs) different from those used by T(reg) cells in other locations, implying an important role for local antigens in shaping the colonic T(reg)-cell population. Many of the local antigens seemed to be derived from commensal bacteria, on the basis of the in vitro reactivity of common colon T(reg) TCRs. These TCRs did not facilitate thymic T(reg)-cell development, implying that many colonic T(reg) cells arise instead by means of antigen-driven peripheral T(reg)-cell development. Further analysis of two of these TCRs by the creation of retroviral bone marrow chimaeras and a TCR transgenic line revealed that microbiota indigenous to our mouse colony was required for the generation of colonic T(reg) cells from otherwise naive T cells. If T cells expressing these TCRs fail to undergo T(reg)-cell development and instead become effector cells, they have the potential to induce colitis, as evidenced by adoptive transfer studies. These results suggest that the efficient peripheral generation of antigen-specific populations of T(reg) cells in response to an individual's microbiota provides important post-thymic education of the immune system to foreign antigens, thereby providing tolerance to commensal microbiota.

OBJECTIVE To investigate patterns in the relapse frequency after curative surgical intervention, with the intention of determining the feasibility of a complete holiday from chemotherapy for metastatic colorectal cancer (mCRC) patients. METHODS Patients with stage IV mCRC who received curative surgical intervention between January 1999 and December 2009 at Changhua Christian Hospital, Changhua, Taiwan were investigated retrospectively. Factors influencing the frequency and pattern of relapse were analyzed by logistic regression. Factors influencing overall survival (OS) were analyzed with Cox proportional hazard ratios. Significant factors were extracted and relationships to OS were evaluated by Kaplan-Meier with Log-Rank test. RESULTS One hundred and thirty-two patients were included in the study in which 94 (71.2%) suffered from relapse. The number of relapses peaked between 3 and 6 months. The incidence of relapse and Disease-free survival had a negative influence on OS, with a hazard ratio (HR) of 0.36 (95% CI: 0.01-0.26) and 0.93 (95% CI: 0.90-0.95). The prognosis was significantly worse when the relapse (n=25) occurred within 6 months after metastectomy (p<0.001). Patients exhibited significantly better long-term OS if the relapse does not occur within 28 months after surgery (p<0.001). CONCLUSION Early relapse indicated a worse prognosis. We determined that if mCRC patients remain cancer-free for 28 months after curative surgery, their chance of long-term survival is significantly better.

BACKGROUND Malignant ovarian tumors in children are relatively rare. We reviewed our 15-year experience to understand their clinical presentations, managements, and prognoses. METHODS There were 15 children who were diagnosed to have malignant ovarian tumors from January 1994 to June 2009 in our hospital. The presenting symptoms, treatments, and outcomes were obtained retrospectively from the medical records. RESULTS The median age at presentation was 13 years. The most common presenting symptom was abdominal pain, occurring in 10 patients (66.7%). The tumors were in the left side in 10 patients (66.7%). The pathologic diagnoses were yolk sac tumors in four patients, immature teratomas in four, dysgerminomas in three, malignant mixed germ cell tumors in three, and carcinosarcoma in one patient. According to the Federation Internationale de Gynecologie Oncologique classification, seven girls had Stage I, one had Stage II, and seven had Stage III disease. Thirteen patients received chemotherapy with platinum-based regimens. Three patients died of their disease: one of yolk sac tumor, one of malignant mixed germ cell tumor, and one of carcinosarcoma. They all had Stage III disease at diagnosis. The 10-year overall survival and disease-free survival rates were 77% and 69%, respectively. CONCLUSIONS Pediatric malignant ovarian tumors were highly curable disease if they were not in the advanced stage at presentation. Earlier consideration of malignant ovarian tumor in the differential diagnosis of young girls with abdominal pain is important.

To describe the epidemiological characteristics of infantile hypertrophic pyloric stenosis (IHPS) in ethnic Chinese children. We reviewed the National Health Insurance claims database and analyzed data from children less than one year of age who had been diagnosed with IHPS (ICD-9-CM 750.5) and had undergone pyloromyotomy (ICD-9-CM 43.3). We analyzed the incidence, gender, age at diagnosis, length of hospital stay, seasonal variation and cost of IHPS from data collected between January 1997 and December 2007. A total of 1,077 infants met inclusion criteria, including 889 boys and 188 girls. The annual incidence of IHPS ranged from 0.30 to 0.47 per 1,000 live births with a mean incidence of 0.39 per 1,000 live births. Between 2002 and 2007, the incidence showed a declining trend (P = 0.025) with coincidentally increasing trends for both exclusive breastfeeding (P = 0.014) and breastfeeding plus bottle feeding (P = 0.004). The male-to-female rate ratio was dynamic and increased from 3.03 during the first two weeks of life to 8.94 during the 8(th) through 10th weeks of life. The overall male-to-female rate ratio was 4.30. The mean age at diagnosis was 43.1 ± 2.4 days. After analyzing the months of birth and hospital admission, no seasonal variation associated with IHPS was detected. The mean length of hospital stay was 8.28 ± 7.10 days. The incidence of IHPS in Taiwan, a country with a majority ethnic Chinese population, was lower than observed incidences in Caucasian populations living in Western countries. Breastfeeding campaigns and low maternal smoking rates may contribute to the lower incidence of IHPS in Taiwan. However, additional studies with longer follow-up periods are needed.