Engineering silicon crystals for photovoltaics

In this highlight, we review the recent engineering efforts in the state-of-the art industrial production of customized silicon crystals, including quasi-mono and multi-crystalline silicon (mc-Si).

Thymic stromal lymphopoietin (TSLP) secretion from human nasal epithelium is a function of TSLP genotype

Recent candidate gene and genome-wide association studies have identified "protective" associations between the single-nucleotide polymorphism (SNP) rs1837253 in the TSLP gene and risk for allergy, asthma, and airway hyperresponsiveness. The absence of linkage disequilibrium of rs1837253 with other SNPs in the region suggests it is likely a causal polymorphism for these associations, having functional consequences. We hypothesized that rs1837253 genotype would influence TSLP secretion from mucosal surfaces. We therefore evaluated the secretion of TSLP protein from primary nasal epithelial cells (NECs) of atopic and nonatopic individuals and its association with rs1837253 genotype. We found that although atopic sensitization does not affect the secretion of TSLP from NECs, there was decreased TSLP secretion in NECs obtained from heterozygous (CT; 1.8-fold) and homozygous minor allele (TT; 2.5-fold) individuals, as compared with NECs from homozygous major allele individuals (CC; P<0.05), after double-stranded RNA (dsRNA) stimulation (50 μg ml(-1)). Our novel results show that rs1837253 polymorphism may be directly involved in the regulation of TSLP secretion. This may help explain the protective association of this genetic variant with asthma and related traits. Identifying functional consequences of SNPs in genes with previously reported clinical associations is critical in understanding and targeting allergic inflammation.

A Biochemical Approach to Understand the Pathogenesis of Advanced Pulmonary Arterial Hypertension: Metabolomic Profiles of Arginine, Sphingosine-1-Phosphate, and Heme of Human Lung

Pulmonary arterial hypertension (PAH) is a vascular disease characterized by persistent precapillary pulmonary hypertension (PH), leading to progressive right heart failure and premature death. The pathological mechanisms underlying this condition remain elusive. Analysis of global metabolomics from lung tissue of patients with PAH (n = 8) and control lung tissue (n = 8) leads to a better understanding of disease progression. Using a combination of high-throughput liquid-and-gas-chromatography-based mass spectrometry, we showed unbiased metabolomic profiles of disrupted arginine pathways with increased Nitric oxide (NO) and decreased arginine. Our results also showed specific metabolic pathways and genetic profiles with increased Sphingosine-1-phosphate (S1P) metabolites as well as increased Heme metabolites with altered oxidative pathways in the advanced stage of the human PAH lung. The results suggest that PAH has specific metabolic pathways contributing to the vascular remodeling in severe pulmonary hypertension. Profiling metabolomic alterations of the PAH lung has provided a new understanding of the pathogenic mechanisms of PAH, which benefits therapeutic targeting to specific metabolic pathways involved in the progression of PAH.

Metabolic syndrome is an independent prognostic factor for endometrial adenocarcinoma

OBJECTIVE

To study the association between metabolic syndrome (MS) and the prognosis of patients with endometrial adenocarcinoma.

METHODS

A total of 385 patients with endometrial adenocarcinoma in the Department of Gynecologic Oncology, at the Zhejiang Cancer Hospital in China, between January 2001 and December 2008 were chosen. The deadline for the completion of follow-up was December 2013. The overall survival (OS) of the patients with MS was analyzed by the Kaplan-Meier method. Various clinical characteristics (e.g., clinical and surgical stage, vascular invasion, histological grade, tumor size, age at start of the first treatment, and lymphatic metastasis) related to the prognosis of endometrial adenocarcinoma were also evaluated.

RESULTS

A univariate analysis demonstrated that the OS rate of the patients with endometrial adenocarcinoma with MS was significantly worse than that of the patients without MS for all 385 patients (P = 0.001). Multivariate Cox proportional hazards regression analyses showed that stage (P = 0.001), lymphatic metastasis (P = 0.021), and MS (P = 0.049) were independent prognostic factors for endometrial adenocarcinoma. Furthermore, statistical analyses demonstrated that MS was closely related to stage (P = 0.021), grade (P = 0.022), vascular invasion (P = 0.044), tumor size (P = 0.035), and lymphatic metastasis (P = 0.014) but not with age at start of the first treatment (P = 0.188). Finally, according to the univariate analysis of the OS rate of 129 cases of endometrial adenocarcinoma with MS, stage (P = 0.001), vascular invasion (P = 0.049), tumor size >2 cm (P = 0.028), lymphatic metastasis (P = 0.002), and CA19-9 value >37 U/m (P = 0.002) all showed significantly low P values for OS.

CONCLUSION

Metabolic syndrome is an independent prognostic factor for endometrial adenocarcinoma.

Receptor-interacting protein kinase 3 is a predictor of survival and plays a tumor suppressive role in colorectal cancer

Receptor-interacting protein kinase 3 (RIP3) is a member of the RIP Ser/Thr kinase family, plays an important role in regulating cell survival, cell apoptosis and cell necrosis. However, the role of RIP3 in the carcinogenesis of colorectal cancer is still poorly understood.We used quantitative PCR and Western blot analysis to examine RIP3 expression in primary colorectal cancer and paired normal colorectal mucosa. RIP3 clinicopathological significance was assessed by immunohistochemical staining in 112 cases of primary colorectal cancer paired with noncancerous tissues. The biological function of RIP3 overexpression was measured by CCK8 assay and plate colony formation assay. Dual staining with fluorescent Annexin V and propidium iodide (PI) was used to discriminate apoptotic or necrotic cell death.RIP3 expression was significantly lower in colorectal cancer and associated with T stage, M stage and AJCC stage. Cox proportional hazard models showed that RIP3 expression was an independent prognostic factor for overall survival and disease-free survival in patients with colorectal cancer. Overexpression of RIP3 significantly suppressed the proliferation of colorectal cancer cells in vitro.Our results suggest that RIP3 may function as a novel prognostic indicator after surgery and play a suppressive role in the colorectal carcinogenesis.

The role of CD4+ T cell subsets in the clearance of Pneumocystis murina pneumonia in mice (MPF6P.734)

Pneumocystis (PC) Pneumonia remains a serious complication in the immuno-compromised host. The host defense against PC is critically dependent upon CD4+ T cells. The role of specific T-cell subsets that mediate host resistance against PC infection remains unclear. We use STAT transcription factor knockout (KO) mice to determine the role of Th1, Th2, and Th17 cells in PC infection. After 28 days infection with PC, serum, lung tissue, and mediastinal lymph node (LN) were collected. LN and lung tissue cells were measured for cytokines by ELISpot and intracellular staining. Total lung RNA was measured for PC burden by RT-qPCR. Cytokines were assayed from cell culture supernatant. Anti-PC antibody was measured by ELISA.Stat4, Stat6 single KO, and Stat4/6 double KO mice all were resistant to PC compared to the Rag2/gc KO mice. Stat4 was required for a Th1 response and Stat6 was required for a Th2 response. STAT3fl/fl/CD4Cre+ mice had partial susceptibility of PC. Stat3 expression was required in CD4+ T cells for PC specific Th17 responses. STAT4/6 double KO crossed to STAT3fl/fl/CD4Cre+ (Triple KO) mice were highly susceptible to PC infection compare to single and double KO mice. Individual Stat4 and 6 and double mutants clear PC. STAT3fl/fl/CD4Cre+ conferred partial susceptibility to PC. Triple KO were as susceptible for PC as Rag2/gc KO mice. These data support the hypothesis that PC is a true opportunist and that various T-cell subsets can confer protection against infection.

Pulmonary Th17 immunity is regulated by regenerating islet-derived III-gamma and the gut microbiome (MUC4P.826)

Antimicrobial proteins provide an innate immune barrier against pathogen invasion. Here we identify a function for the bactericidal lectin regenerating islet-derived III-gamma (RegIIIγ) in shaping CD4 T cell polarization. Gram-positive bacteria in the intestine induce RegIIIγ expression, which modulates the immune tone of the gut, resulting in decreased Th17-type immunity during pulmonary fungal infection. This was associated with RegIIIγ inhibiting intestinal colonization with segmented filamentous bacteria (SFB), a pro-inflammatory commensal that augments Th17 differentiation. Vancomycin drinking water inhibited IL-17 production in lungs of RegIIIγ-/- and Il22-/- mice, demonstrating that intestinal Gram-positive commensals contribute to systemic inflammation. Reconstituting Il22-/- mice with IL-22 decreased the SFB/Clostridium ratio, while gastrointestinal delivery of recombinant RegIIIγ decreased inflammatory gene expression in lung tissue and protected Il22-/- mice from weight-loss during Aspergillus fumigatus infection. Therefore, intestinal antimicrobial proteins influence the development of adaptive immunity by altering the balance of pro- and anti-inflammatory intestinal commensal species.

Abstract P2-09-22: Synthesis of nitroxyl radical-containing nanoparticles with pH-sensitive behavior and their application for cancer therapy

Extensive research has documented that redox dysregulation is a causative involvement in tumor progression, and reactive oxygen species (ROS) are involved in cancer initiation and progression. ROS are mutagenic and may promote cancer. Early studies observed that the increased ROS production was in response to oncogenic activity. It is now widely accepted that redox chemotherapeutics represents a novel class of promising anticancer agents. Small molecule nitroxides are stable free radicals which are able to scavenge radicals and act as radical chain reaction terminators. Nitroxyl radical, 2, 2, 6, 6-tetramethyl-piperidine-1-oxyl (TEMPO), is capable of reacting with ROS and shows chemotherapeutic efficacy in various cancer cell lines and xenograft models. However, low-molecular-weight TEMPO derivatives are hard to utilize in the clinic, owing to a preferential renal clearance and side effects such as antihypertensive effect.

To address these issues, we have designed and developed nitroxyl radical-containing nanoparticles with pH-sensitive behavior using the first generation PAMAM (G1 PAMAM) partially modified with 3,4,5,6-tetrahydrophthalic anhydride (THPA) and PROXYL. The synthesis of the modified PAMAM was carried out by a two-step reaction. Firstly, part of the primary amine end group of PAMAM dendrimers reacted with anhydride THPA to produce a THPA-modified PAMAM. The b-carboxylic acid amides between G1 PAMAM and THPA are acid-sensitive. Therefore, the THPA-modified PAMAM are stable and negatively charged at physiological pH, thus preventing blood serum aggregation. However, the THPA-modified PAMAM degrades at acidic pH, converting its surface to positive charge which is benefit for cellular uptake. Secondly, the THPA-modified PAMAM reacted subsequently with 3-carboxy-PROXYL whose carboxyl group was activated by N-hydroxysuccinimide. The EPR signal of the product was analyzed by EPR measurement and confirmed the PROXYL group covalently conjugated onto THPA-modified PAMAM. The obtained THPA-PROXYL-modified PAMAM was denoted as TP-PAMAM. Experimental results showed that TP-PAMAM was stable at pH 7.4, and hydrolyzed at pH 6.0. The rate of hydrolysis was increased with pH decreasing. In vitro studies indicated that cell proliferation of MDA-MB-231 was greatly inhibited by TP-PAMAM compared to low-molecular-weight TEMPO. This may due to the fact that cellular uptake is easy for nanoparticles with pH-sensitive behavior. Therefore, the nitroxyl radical conjugated onto the pH-sensitive nanoparticles scavenges ROS more effectively. As a result, these new nitroxyl radical-containing nanoparticles have a significantly high therapeutic efficacy in the application for cancer therapy. Hence, engineered nitroxyl radical-containing nanoparticles with pH-sensitive behavior may enable therapeutic selectivity and to overcome drug resistance and metastatic cancer.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-09-22.

Bioavailability of quercetin: problems and promises

Quercetin (QC) is a typical plant flavonoid, possesses diverse pharmacologic effects including antiinflammatory, antioxidant, anti-cancer, anti-anaphylaxis effects and against aging. However, the application of QC in pharmaceutical field is limited due to its poor solubility, low bioavailability, poor permeability and instability. To improve the bioavailability of QC, numerous approaches have been undertaken, involving the use of promising drug delivery systems such as inclusion complexes, liposomes, nanoparticles or micelles, which appear to provide higher solubility and bioavailability. Enhanced bioavailability of QC in the near future is likely to bring this product to the forefront of therapeutic agents for treatment of human disease.

2D and 3D anatomical analyses of hand dimensions for custom-made gloves

Measuring hand anthropometric data for the development of good-fitting gloves is crucial. In pursuing higher accuracy in hand anthropometric measurements, scanning of hand surfaces with the aids of image analysis system to acquire measurements is an alternative to the manual methods. This study proposes a new hand measuring approach by using 2D and 3D scanning which are evaluated through comparisons of manual measurements. Thirty-three dimensions are measured by using (1) tape and calliper measurement; (2) 2D image analysis; (3) 3D image analysis based on ten captures; and (4) 3D image analysis based on three captures, respectively. Repeated-measures ANOVA, correlation analysis and RMSE are used to examine the results. The hand dimensions obtained from the four methods are highly linearly correlated. Hand data taken from 3D image analysis has no significant difference compared with manual measurements on hand and wrist circumferences, length and breadth dimension, regardless of the number of captures.

[Mechanisms, clinical profile and role of prostaglandin and prostamide analogues in antiglaucomatous therapy]

Prostaglandin and prostamide analogues belong to a new substance group which came into the market in the 1990s. They have revolutionised antiglaucomatous therapy by their once-daily dosing regimen and fewer side effects. Today, prostaglandin and prostamide analogues are approved as first-line therapy for patients with primary open-angle glaucoma and ocular hypertension. They lower the intraocular pressure primarily by increasing the uveoscleral outflow. Recent investigations have shown that they also improve the trabecular outflow facility and thus the conventional outflow pathways. Prostaglandin and prostamide analogues are highly efficient in lowering the intraocular pressure, for which they are superior to other antiglaucomatous substance groups. In particular, they appear to have a good control of 24-hour intraocular pressure fluctuations by primarily improving the outflow pathways. Furthermore, they have less systemic side effects than β-blockers. However, their use is often associated with higher costs. In case of undesirable events, they mostly present with ocular symptoms. Based on their good clinical profile, prostaglandin and prostamide analogues play an important role in the primary and additive therapy for glaucoma.

Comparative Efficacy of miniKexin DNA versus protein vaccination against Pneumocystis infection. (166.13)

Pneumocystis Pneumonia (PCP) is a leading cause of death in individuals with AIDS or other immunocompromised conditions. We have previously shown that mice vaccinated with DNA encoding full-length PC antigen Kex1 have approximately a three-log reduction in PC organism burden after challenge. Full length Kex1 is poorly expressed so to improve on this we developed codon optimized vectors expressing a truncated conserved form of Kex1, mini-kexin. This also allowed investigation of a prime boost strategy since mini-kexin could be efficiently packaged into recombinant adenovirus. Mice were vaccinated with DNA encoding mini-kexin followed by boosting with adenovirus, CD4+ T cells were then depleted by GK1.5, and finally the mice were challenged with live Pneumocystis. The results showed significantly reduced PC burden in vaccinated mice. We then proceeded to generate a protein-based, E coli produced vaccine, however, this time vaccine elicited similar anti-Kex1 titers but lacked protection. We hypothesize that post-translational modification such as glycosylation could play a role in the efficacy of mini-kexin vaccination.