Laser ablation of a bulk Cr target in liquids for nanoparticle synthesis

Chromium carbide nanoparticles in the metastable phase are synthesized by laser ablation of a bulk chromium target in acetone or toluene.

Response of discharge, TSS, and E. coli to rainfall events in urban, suburban, and rural watersheds

Understanding dominant processes influencing microorganism responses to storm events aids in the development of effective management controls on pathogen contamination in surface water so that they are suitable for water supply, recreation, and aquatic habitat. Despite the urgent needs at present, numerous facets of microbial transport and fate are still poorly understood. Using correlation and multiple regression combined with spatial analyses, this paper evaluates the relationship between antecedent precipitation and discharge, TSS, and E. coli concentrations, and examines correlations between E. coli and TSS, as well as whether and how those relationships change along an urban and rural gradient. The urban watershed exhibited a faster and stronger response of streamflow, TSS, and E. coli to precipitation mainly due to its higher degree of imperviousness. In general, TSS was significantly correlated with E. coli concentrations, which linearly decreased as % developed area increased, with large variation in regions with a high percentage of development, implying the more complex stormwater infrastructure and more variable pollutant sources of E. coli in the urban watershed. Seasonal differences for E. coli were noted. Specifically, summer showed a higher level of E. coli, which might be attributed to the higher temperature since E. coli is more likely to persist and grow in a warmer environment. Further multiple linear regression analyses showed the best E. coli prediction result for the largest, suburban watershed, using antecedent precipitation, TSS, and temperature as independent variables. The models are capable of explaining 60% and 50% of the variability in the E. coli concentration for the dry and wet season, respectively. The study not only provides more detailed and accurate characterization of the storm-period response of E. coli across an urban and rural gradient, but also lays a foundation for predicting the concentration of E. coli in practice, potentially suggesting effective watershed management decisions.

In-Line Density Monitoring of Rigid PVC Foam during Extrusion Process

An ultrasound-based sensor has been investigated to monitor the density of rigid PVC foam, in-line, during the extrusion process. A 2.25 MHz ultrasound transducer was used to measure the acoustic properties; i.e. speed of sound, acoustic impedance, and attenuation, in the polymer melt prior to exiting the extrusion die. A special transducer adapter and wave re ector were incorporated in the design of the extrusion die. The density of PVC foam was varied by varying the blowing agent content in the resin compound prior to extrusion. A mathematical derivation of the behavior of ultrasound waves in the melt is presented and used to calculate the attenuation coefficient of the polymer melt at various foam densities. An empirical relation was derived between the calculated attenuation coefficient of the polymer melt and the measured density of the foam extrudate. This relation can be used to estimate the foam density based on the acoustic measurement of the melt in the extrusion die. Further work is proposed to normalize for the effect of variations in the melt temperature and pressure on the ultrasound measurements.

Acute Myocardial Injury in a 45-year-old Female: Hypereosinophilic Syndrome

Hypereosinophilic syndrome (HES) can cause eosinophilic infiltration in multiple organ systems resulting in organ damage. Among all, cardiac involvement is the major cause of morbidity and mortality. Early diagnosis and prompt treatment are important to improve the prognosis. We reported a 45-year-old woman with a history of eosinophilia presented with chest pain in our emergency department. Laboratory tests revealed marked eosinophilia and elevated cardiac markers. A neurological event, presenting as right-side limb weakness, supervened later. The diagnosis of HES was established, and prompt treatment with corticosteroids, hydroxyurea, and imatinib resolved the eosinophilia; further cardiac and neurological injury was thus prevented. This case reminds us to consider and, if applicable, to provide the appropriate management for HES in the context of making a differential diagnosis in clinical situations involving organ damage.

Derivation of freshwater quality criteria for zinc using interspecies correlation estimation models to protect aquatic life in China

Species sensitivity distributions (SSDs) are usually used in the development of water quality criteria and require a large number of toxicity values to define a hazard level to protect the majority of species. However, some toxicity data for certain chemicals are limited, especially for endangered and threatened species. Thus, it is important to predict the unknown species toxicity data using available toxicity data. To address this need, interspecies correlation estimation (ICE) models were developed by US EPA to predict acute toxicity of chemicals to diverse species based on a more limited data set of surrogate species toxicity data. Use of SSDs generated from ICE models allows for the prediction of protective water quality criteria, such as the HC5 (hazard concentration, 5th percentile). In the present study, we tested this concept using toxicity data collected for zinc. ICE-based-SSDs were generated using three surrogate species (common carp (Cyprinus carpio), rainbow trout (Oncorhynchus mykiss), and Daphnia magna) and compared with the measured-based SSD and corresponding HC5. The results showed that no significant differences were observed between the ICE- and the measured-based SSDs and HC5s. Furthermore, the examination of species placements within the SSDs indicated that the most sensitive species to zinc were invertebrates, especially crustaceans. Given the similarity of SSD and HC5s for zinc, the use of ICE to derive potential water quality criteria for diverse chemicals in China is proposed. Further, a combination of measured and ICE-derived data will prove useful for assessing water quality and chemical risks in the near future.

Modified diadenosine tetraphosphates with dual specificity for P2Y1 and P2Y12 are potent antagonists of ADP-induced platelet activation

BACKGROUND

Diadenosine 5',5'''-P(1),P(4)-tetraphosphate (Ap(4)A), a natural compound stored in platelet dense granules, inhibits ADP-induced platelet aggregation. Ap(4)A inhibits the platelet ADP receptors P2Y(1) and P2Y(12), is a partial agonist of P2Y(12), and is a full agonist of the platelet ATP-gated ion channel P2X1. Modification of the Ap(4)A tetraphosphate backbone enhances inhibition of ADP-induced platelet aggregation. However, the effects of these Ap(4)A analogs on human platelet P2Y(1), P2Y(12) and P2X1 are unclear.

OBJECTIVE

To determine the agonist and antagonist activities of diadenosine tetraphosphate analogs towards P2Y(1), P2Y(12), and P2X1.

METHODS

We synthesized the following Ap(4)A analogs: P(1),P(4)-dithiotetraphosphate; P(2),P(3)-chloromethylenetetraphosphate; P(1)-thio-P(2),P(3)-chloromethylenetetraphosphate; and P(1),P(4)-dithio-P(2),P(3)-chloromethylenetetraphosphate. We then measured the effects of these analogs on: (i) ADP-induced platelet aggregation; (ii) P2Y(1)-mediated changes in cytosolic Ca(2+); (iii) P2Y(12)-mediated changes in vasodilator-stimulated phosphoprotein phosphorylation; and (iv) P2X1-mediated entry of extracellular Ca(2+).

RESULTS

Ap(4)A analogs with modifications in the phosphate backbone inhibited both P2Y(1) and P2Y(12), and showed no agonist activity towards these receptors. The dithio modification increased inhibition of P2Y(1), P2Y(12), and platelet aggregation, whereas the chloromethylene modification increased inhibition of P2Y(12) and platelet aggregation, but decreased P2Y(1) inhibition. Combining the dithio and chloromethylene modifications increased P2Y(1) and P2Y(12) inhibition. As compared with Ap(4)A, each modification decreased agonist activity towards P2X1, and the dual modification completely eliminated P2X1 agonist activity.

CONCLUSIONS

As compared with Ap(4)A, tetraphosphate backbone analogs of Ap(4)A have diminished activity towards P2X1 but inhibit both P2Y(1) and P2Y(12) and, with greater potency, inhibit ADP-induced platelet aggregation. Thus, diadenosine tetraphosphate analogs with dual receptor selectivity may have potential as antiplatelet drugs.

Technique for Resonance® stent exchange in patients with extrinsic obstruction: description of a novel approach and literature review

Malignant ureteral obstruction is a morbid diagnosis and can be difficult to manage. Ureteral stents often fail as the disease progresses. Metallic stents have provided a longer-term option for decompression as they inherently resist compression and require changes left often. However, changing metallic stents is challenging as it cannot be done over a wire as is done with plastic stents. We present a novel technique for safe and efficient exchange of the Resonance(®) metallic stent. We also review the literature on metallic stents.

Factors related to the development of myelopathy in patients with cervical ossification of the posterior longitudinal ligament

This study evaluates factors related to myelopathic symptoms in patients with ossification of the posterior longitudinal ligament (OPLL). A total of 87 patients with OPLL were included. Of these, 53 (Group I) had no symptoms or presented with neck pain and radiculopathy and 34 (Group II) had myelopathic symptoms. Gender, age, and history of trauma were evaluated in the two groups. The range of movement of the cervical spine was measured using plain radiographs. The number of involved segments, type of OPLL, and maximal compression ratio were analysed using CT and signal change in the spinal cord was evaluated using MRI. The patients' age was found to be significant (p = 0.001). No difference was found between gender and the range of movement in the two groups. The maximum compression of the spinal canal showed a difference (p = 0.03). The signal change of the spinal cord was different between the two groups. In patients with OPLL of the cervical spine, myelopathic symptoms are not related to the range of movement or the number of involved segments.

Human B-cell ontogeny in humanized NOD/SCID γc(null) mice generates a diverse yet auto/poly- and HIV-1-reactive antibody repertoire

Characterization of the human antibody (Ab) repertoire in mouse models of the human immune system is essential to establish their relevance in translational studies. Single human B-cells were sorted from bone marrow and periphery of humanized NOD/SCID γc^null mice at 8–10 months post-engraftment with human cord blood-derived CD34⁺ stem cells. Human immunoglobulin variable heavy (V_H) and kappa (V_κ) genes were amplified, cognate V_H-V_κ gene-pairs assembled as single-chain variable fragment-Fc antibodies (scFvFcs) and functional studies performed. Although overall distribution of V_H genes approximated the normal human Ab repertoire, analysis of the V_H-third complementarity determining regions (H-CDR3) in the mature B-cell subset demonstrated an increase in length and positive charges suggesting autoimmune characteristics. Additionally, >70% of V_κ sequences utilized V_κ4-1, a germline gene associated with autoimmunity. The mature B-cell subset-derived scFvFcs displayed the highest frequency of autoreactivity and polyspecificity, suggesting defects in checkpoint control mechanisms. Furthermore, these scFvFcs demonstrated binding to recombinant HIV envelope corroborating previous observations of poly/autoreactivity in anti-HIVgp140 antibodies. These data lend support to the hypothesis that anti-HIV BnAbs may be derived from auto/polyspecific Abs that escaped immune elimination and that the hNSG mouse could provide a new experimental platform for studying the origin of anti-HIV neutralizing Ab responses.

Expression of adhesion molecules and mucins in human and rhesus macaque gastrointestinal epithelial cells

Epithelial junctions and mucins play key roles in the gastrointestinal mucosal barrier, and their alterations are associated with numerous diseases, including carcinomas. The systematic expression of adhesion molecules and mucins in normal and malignant human gastrointestinal cells was investigated in this study. In normal human gastrointestinal cells, zonula occludens-1 (ZO-1), α-catenin, β-catenin, γ-catenin and desmoglein-2 (DSG2) were located in the cytoplasmic membranes, whereas symplekin stained in the nuclei. ZO-1, the three catenins, and DSG2 were observed in the gastric and colorectal carcinomas with reduced and heterogeneous expression and with abnormal distribution. Symplekin was detected in the nuclei of tumor cells in most tumors but not observed in some others. The immunohistochemical results for ZO-1 and symplekin on the tissues were consistent with the data for the cultured cells obtained by immunocytochemical staining and Western blot analysis. MUC1 was not stained in the normal gastrointestinal cells without periodate oxidation, but it was strongly labeled in the malignant gastrointestinal cells. MUC2 was detected in the normal and malignant gastrointestinal cells without the periodate treatment. These findings indicate that alterations in the expression of the epithelial junctions and mucins are associated with the malignant transformation of gastrointestinal cells. In addition, the gastrointestinal epithelial cells of rhesus macaques expressed these adhesion molecules and mucins, as did the human cells, suggesting that the rhesus monkey is a suitable experimental animal model for research on adhesion molecules and mucins.

Collision in the colon: concurrent adenocarcinoma and diffuse large B-cell lymphoma in the same tumour

Double malignancies in the gastrointestinal tract are unusual. Concurrent lymphoma and adenocarcinoma is a rare clinical condition. We herein report a collision tumour which first presented with a diffuse large B-cell lymphoma in the skull base and ileocecal junction area. After rituximab and chemotherapy the skull base tumour disappeared, but the ileocecal lesion remained. A biopsy revealed the presence of adenocarcinoma in the same lesion. The tumour was surgically removed. Further microscopic examination of the tumour showed it was an adenocarcinoma but residual lymphoma cell infiltration could still be observed. Serum Epstein-Barr virus (EBV) was detected at diagnosis of lymphoma and the concentration further elevated at diagnosis of adenocarcinoma. Therefore, both lymphoma and carcinoma may be EBV related. Our experience illustrated that such collision tumours are rare and difficult in diagnosis. Clinicians and pathologists should be aware of such an association in order to make a correct diagnosis and initiate proper treatment.

Aryl hydrocarbon receptor in association with RelA modulates IL-6 expression in non-smoking lung cancer

Aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that is activated by cigarette smoke. Previously, we demonstrated that AhR is overexpressed in lung adenocarcinomas (ADs). In this study we observed that AhR expression is significantly correlated with nuclear RelA (a nuclear factor-κB (NFκB) subunit) and cytosolic interleukin-6 (IL-6) in 200 non-small cell lung cancer patients, especially among never smokers. Overexpression of AhR increased IL-6 expression in H1355 cells and immortalized human bronchial epithelial cells BEAS-2B. As NFκB inhibitor and knockdown RelA expression greatly reduced constitutive AhR-induced IL-6 expression, we hypothesized that AhR expression, in the absence of exogenous ligand, is able to modulate NFκB activity and subsequently upregulate IL-6 expression, thus promoting the development of lung AD. Specifically, AhR overexpression significantly increased NFκB activity, whereas interference with AhR expression significantly reduced NFκB activity and IL-6 expression in H1355 cells. We demonstrated that AhR associates with RelA in the cytosol and nucleus of human lung cells. Furthermore, AhR overexpression enhanced nuclear localization of AhR and RelA, and increased the association of AhR-RelA with the NFκB response element of the IL-6 promoter. However, p50 was not involved. Our results indicate that AhR, without exposure to a ligand, associates with RelA, which then positively modulates NFκB activity and then upregulates IL-6 expression in human lung cells. Thus we have identified a new mechanism for lung tumorigenesis in non-smokers.

Phase III study of gemcitabine/oxaliplatin (GEMOX) with or without erlotinib in unresectable, metastatic biliary tract carcinoma

LBA4032

Background: Currently, there is no standard regimen for palliative chemotherapy in metastatic, unresectable biliary tract cancer (BTC). A phase II trial of erlotinib monotherapy showed a promising anti-tumor activity in BTC with tolerable toxicity. Additionally, gemcitabine + erlotinib demonstrated superior efficacy when compared to gemcitabine alone in pancreatic cancer. Hence, we conducted a phase III trial to compare between GEMOX vs GEMOX+erlotinib (Tarceva [T]) (GEMOX/T) as first-line chemotherapy in unresectable, metastatic BTC. Methods: Eligible patients were as follows: histologically confirmed adenocarcinoma of biliary tract (CCC), ampulla of vater (AOV) or gall bladder (GB); unresectable or metastatic; ECOG performance status of 0~2; adequate marrow, hepatic, renal and cardiac functions; no prior chemotherapy. The primary endpoint was progression free survival (PFS). The study regimen was gemcitabine 1,000mg/m2, oxaliplatin 100mg/m2, erlotinib 100mg qd daily q 2 weeks. Results: From February 2009 to August 2010, 268 pts were randomized, 133 patients to GEMOX arm and 135 patients to GEMOX/T arm. Patient characteristics: median age 61 yrs (range 30-82); male (63.4%); CCC (n=180, 67.2%), GB (n=82, 30.6%), and AOV (n=6, 2.2%). With a median follow-up of 13.9 months (range, 6.7 – 25.0), median PFS was 5.8 months (95% CI, 4.6 - 7.0) in GEMOX/T arm and 4.2 months (95% CI, 2.7 - 5.7) in GEMOX arm (P=0.080). In subgroup analysis (CCC, n=180), however, median PFS was significantly longer in GEMOX/T arm (5.9 months) when compared with GEMOX arm (3.0 months, P=0.049). The overall response rate was significantly higher in the GEMOX/T arm when compared with GEMOX arm. There was no significant difference in overall survival between the two arms (GEMOX/T: 9.5 months, 95% CI, 7.6 – 11.4; GEMOX: 9.5 months, 95% CI, 7.5 – 11.5; P=0.611). The EGFR mutation testing results in correlation to responsiveness to erlotinib will be presented at the meeting. Conclusions: This phase III represents the first multicenter, randomized trial to compare GEMOX vs GEMOX/T in unresectable, metastatic BTC. Although PFS was not prolonged in GEMOX/T, there was a significant benefit in terms of PFS in GEMOX/T arm for CCC patients.

Development and preliminary validation of the PC-SAD5, a screener-derived short depression severity measure

BACKGROUND

The prevalence of depressive disorders is high among patients with skin disease. The PC-SAD is a 37-item self-administered depression screening questionnaire that has been validated in dermatological patients.

OBJECTIVE

The aim of this study was to develop and validate a brief depression severity instrument derived from the PC-SAD that can be used to assess severity and monitor ongoing clinical course.

METHODS

Two patient samples participated in the study: 72 adult dermatological inpatients and 73 adults attending six primary care practices. Psychiatric assessment included the Structured Clinical Interview for DSM-IV and an 18-item version of the PC-SAD; moreover, dermatological patients completed the Patient Health Questionnaire depression scale (PHQ-9), while primary care patients were administered the Montgomery-Asberg Depression Rating Scale (MADRS). A subset of five PC-SAD items showing the best psychometric properties were selected, and the reliability and validity of the resulting instrument (PC-SAD5) were examined.

RESULTS

The PC-SAD5 showed satisfactory internal consistency in both samples. There was a high correlation between PC-SAD5 and PHQ-9 and MADRS scores. Multiple regression analysis revealed a gradient of PC-SAD5 scores from patients with no mental disorder, those with milder forms of depression, to those with Major Depressive Disorder. Similar results were observed for the 18-item version of the PC-SAD.

CONCLUSION

The availability of valid and reliable continuous measures of depression severity derived from the PC-SAD extends its field of application from depression screening to use as a follow-up measure of depression severity in routine clinical practice. A validated very short instrument such as the PC-SAD5 may have substantial clinical value.

The phylogeographic system survey of native sheep breeds in the eastern and southern Central Asia

The genetic diversity and phylogenetic survey of native sheep breeds in the eastern and southern Central Asia were assessed in the present study. The clustering, principal components, structure and F statistics all demonstrate that the native sheep breeds in these regions be classified into two genetic groups: Mongolia-Tibetan sheep group and South-Southeast Asia sheep group. The Mongolia sheep group and the Tibetan sheep group had a certain degree of gene communication from the ancient times. In the present study we demonstrated that the Chinese native sheep populations belonged to Mongolia-Tibetan sheep group. However, the relationships among the sheep populations in Mongolia sheep group in China were not closely related to the geographical distance among sheep populations.