Effect of Postsymptom Application of Fungicides on Urediniospore Production by Puccinia triticina on Wheat and P. hemerocallidis on Daylily

Greenhouse experiments were conducted to evaluate the effect of post-symptomatic fungicide applications on urediniospore production of leaf rust of wheat, Puccinia triticina, and daylily rust, P. hemerocallidis. Fungicides from five chemical classes were evaluated for their effect on urediniospore production at 24-h intervals post application for 96 h. The quinone outside inhibitor (QoI) fungicide (azoxystrobin) significantly reduced cumulative urediniospore production by P. triticina (40.1 and 11.3% of control) and P. hemerocallidis (37.9 and 35.6% of control) in both trials. The demethylation inhibitor, myclobutanil, significantly reduced urediniospore production by P. hemerocallidis 24 h post treatment in both trials and cumulative production in one trial. Myclobutanil did not affect urediniospore production by P. triticina. Four QoI fungicides significantly reduced urediniospore production by P. triticina at all collection times (24, 48, and 72 h) and cumulative production in both trials. No differences were observed between the QoI fungicides with P. triticina. The four QoI fungicides significantly reduced urediniospore production by P. hemerocallidis compared with the nonfungicide control, with significantly fewer urediniospores produced in the pyraclostrobin-treated lesions compared with azoxystrobin, fluoxastrobin, and trifloxystrobin. Differences in leaf morphology between daylily and wheat such as leaf thickness and waxiness may contribute to the differences observed between the two pathosystems. The significant reductions in urediniospore production by postsymptom applications of QoI fungicides, combined with their known fungistatic properties, suggest that these chemistries would be useful for reducing the spread of viable inoculum to noninfested plants.

Fluids in porous media. III. Scaled particle theory

Based on a new and consistent formulation of scaled particle theory for a fluid confined in random porous media, a series of new approximations are proposed and one of them gives equations of state with excellent accuracy for a hard sphere fluid adsorbed in a hard sphere or an overlapping hard sphere matrix. Although the initial motivation was to remedy a flaw in a previous formulation of the scaled particle theory for a confined fluid, the new formulation is not a trivial and straightforward correction of the previous one. A few conceptual and significant modifications have to be introduced for developing the present formulation.

Survival by anatomic site, histologic type, and tumor stage in stomach and esophageal cancer patients from the U.S. SEER Cancer Registry

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Background: Data on the association of tumor characteristics and survival for stomach cancer (SC) and esophageal cancer (EC) patients (pts) are limited. The objective of this study was to describe survival in United States. SC and EC pts by anatomic site, histologic type, and tumor stage.

Methods: SC and EC pts were identified in the Surveillance, Epidemiology and End Results (SEER) Cancer Registry. SC was classified by anatomic site (cardia and non-cardia/other) and histologic type (intestinal, diffuse, other per Lauren criteria). EC was classified into anatomic site (middle/upper third, abdominal/lower third, overlapping lesions, NOS) and histologic type (adenocarcinoma (AC), squamous cell carcinoma (SQ), other). Frequency distribution and median survival were examined in these subgroups.

Results: From 2004-2006, >15,500 SC and > 9,800 EC cases were diagnosed. SC: (29% cardia) and (24% diffuse, 66% intestinal, 10% other). Compared with non-cardia/other pts, cardia pts tended to be male (77% vs 56%), white (88% vs 66%), intestinal type (77% vs 61%) and present with earlier stage disease (stage I-IIIa: 48% vs 42%). With the exception of stage I/II pts, survival was longer in cardia than non-cardia/other pts. The difference was most striking in stage IIIb/IV pts (7 months (mos) cardia vs 4 mos non-cardia/other). Compared to intestinal type, diffuse type tended to be younger (median age: 64 vs 72 yrs), more female (49% vs 34%), and present with more stage IIIb/IV disease (50% vs 39%). No difference in survival by histologic type was observed when accounting for stage. EC: (26% middle/upper, 58% lower, 5% overlapping, 11% NOS) and (57% AC, 34% SQ, 9% other). Among pts with AC histology 78% occurred in the lower third; in SQ most occurred in upper/middle third (56%). Compared to SQ, AC tended to be male (85% vs 63%), white (95% vs 67%), and present with stage IV disease (34% vs 25%). For all stages combined, survival was longer for AC pts (11 mos AC, 9 mos SQ, 4 mos other). This difference was most apparent among early stage (I-III) pts.

Conclusions: Survival in SC and EC was associated with staging, anatomic and histologic subtypes. Quantifying this provides insights for the design and interpretation of clinical development programs.

[Table: see text]

p85α mediates p53 K370 acetylation by p300 and regulates its promoter-specific transactivity in the cellular UVB response

Inducible acetylation of p53 at lysine residues has a great impact on regulating the transactivation of this protein, which is associated with cell growth arrest and/or apoptosis under various stress conditions. However, the factor(s) for regulating p53 acetylation remains largely unknown. In the current study, we have shown that p85α, the regulatory subunit of phosphatidylinositol-3-kinase, has a critical role in mediating p53 acetylation and promoter-specific transactivation in the ultraviolet B (UVB) response. Depletion of p85α in mouse embryonic fibroblasts significantly impairs UVB-induced apoptosis, as well as p53 transactivation and acetylation at Lys370 (Lys373 of human p53); however, the accumulation, nuclear translocation and phosphorylation of p53 are not affected. Interestingly, p85α binds to p300, promotes the p300-p53 interaction and the subsequent recruitment of the p53/p300 complex to the promoter region of the specific p53 target gene in response to UVB irradiation. Moreover, ablation of p53 acetylation at Lys370 by site-directed mutagenesis dramatically suppresses UVB-induced expression of the specific p53-responsive gene as well as cell apoptosis. Therefore, we conclude that p85α is a novel regulator of p53-mediated response under certain stress conditions, and targeting the p85α-dependent p53 pathway may be promising for cancer therapy.

Note: A novel integrated microforce measurement system for plane-plane contact research

The evaluation of plane-plane contact force has become a big issue in micro-/nano research, for example in microassembly. However with the lack of effective experimental equipments, the research on plane-plane contact has been limited to theoretical formulations or virtual simulation. In this paper, a microforce sensor and precision parallel robot integrated system is proposed for the microforce measurement of plane-plane contact. In the proposed system, the two objects are fixed on the parallel robot end-platform and the microforce sensor probe tip, respectively, and the high precision robot system is employed to provide six degree-of-freedom motions between both objects. So it is convenient for the microforce measurement between the planar objects with different orientations. As a significant application, the proposed system is utilized for measurements of pull-off force between planar objects, in which the validation of the system is demonstrated in practice. The proposed microforce measurement system is generic, which can be extended to a variety of microforce measurements in plane-plane contact.

Antibacterial silver-containing silica glass prepared by ion implantation

Recently, there is much interest in nanocomposites consisting of metal nanoparticles dispersed in dielectric matrix. Silver is the first candidate used in antibacterial research. In the present study, sliver-containing silica glass is prepared by ion implantation. The bactericidal properties of Ag-implanted samples are investigated using E. coli. The implanted samples are characterized by optical absorption spectroscopy, atomic force microscopy and transmission electron microscopy. The size and position of the silver nanoparticles formed by ion implantation can be optimized by adjusting the implanted process parameters. All the implanted samples show antibacterial properties. But the samples with silver nanoparticle-enriched surfaces possess excellent antibacterial properties in comparison with other implanted samples. This indicates that ion implantation is a potential method for synthesizing antibacterial biomaterials.

The temporal expression and localization of extracellular matrix metalloproteinase inducer (EMMPRIN) during the development of periodontitis in an animal model

BACKGROUND AND OBJECTIVE

We previously demonstrated extracellular matrix metalloproteinase inducer (EMMPRIN) was associated with the matrix metalloproteinases production of human periodontitis. The aim of this study was to investigate the temporal expression and localization of EMMPRIN during ligature-induced periodontitis in rats.

MATERIAL AND METHODS

Periodontitis was induced in rats by placing a thread around the cervix of the first mandibular molar. Animals were killed 3, 7, 11, 15 or 21 d after ligation. Mandibles were processed for paraffin sections and stained with hematoxylin and eosin or picrosirius red. The distance from the amelocemental junction to the alveolar crest (ACJ-AC) and the area fraction (Area%) of collagen fibers were measured. EMMPRIN was examined by immunohistochemistry and quantified by positive cell counting. Correlation analyses were then performed.

RESULTS

Histologically, alveolar bone was gradually destroyed from day 3 to 11 and then stabilized. Collagen fibers were slightly dissociated on day 3 and extensively broken on day 7. They were reconstructed from day 11 to 21. EMMPRIN was localized predominantly in infiltrating cells and adjacent fibroblasts in interdental gingiva. The number of EMMPRIN-positive cells increased on day 3, peaked on day 7 and then gradually subsided from day 11 to 21. Statistically, there was a moderate positive correlation regarding the ACJ-AC distance (r = 0.552, p < 0.01) and a strong negative correlation with the Area% of collagen fibers (r = -0.808, p < 0.01). In gingival epithelium, the immunoreactivity was extremely strong in basal layer cells and sulcular epithelial cells in health. It was greatly enhanced in the inflamed conditions on days 3 and 7. In the interradicular bone, EMMPRIN was localized in the osteoclasts on days 3 and 7, as well as in the osteoblasts from day 11 onwards.

CONCLUSION

The expression and localization of EMMPRIN are temporally varied during the development of periodontitis. In addition, the inflammation-dependent expression of EMMPRIN might be involved in alveolar bone resorption and collagen breakdown.

Clinicopathologic predictors of distant metastasis in head and neck cancer

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Background: Despite advances in achieving improved locoregional control for patients with head and neck cancer (HNC), overall survival has not improved in the last 30 years. Several studies have implicated distant metastasis as a potential cause, hindering progress in the treatment of HNC. However, little is known about which patients fail systemically. We therefore sought to identify clinico-pathological factors that are associated with distant metastasis as the only cite of failure. Methods: We retrospectively studied 389 patients with head neck squamous cell carcinomas with distant metastases as the primary site of failure excluding all patients with locoregional recurrence and those receiving chemotherapy at primary presentation. The median follow up period was 5.3 years. An estimate of the risk of DM and DM free survival by prognostic factors was calculated using multivariate analysis and Cox proportional modeling. Results: Overall, 11% (43/389) of the patients developed DM. With univariate analysis, site of the tumor arising within the laryngopharynx, T stage (T3–4), N stage>2, and metastasis to level IV were significantly associated with DM. However, using Cox proportional hazards regression modeling, two clinicopathologic variables, N classification >N2b and diminishing degree of histologic differenention, were found to be most significantly associated with the development of systemic, distant metastasis. For patients staged as N2b or N2c, there was a relative risk (RR) of 6.13 (95% CI: 2.61 - 14.38; p < 0.0001) for developing DM. For patients staged as N3, the RR was 8.23 (95% CI: 2.39 - 28.38; p < 0.001). For patients with poorly differently HNSCC, RR was 11.01 (95% CI: 1.42 - 85.15; p = 0.022) Conclusions: Recognizing patients at primary presentation with tumors with the highest risk for the development of DM might le us to selectively treat them aggressively with systemic therapy to eradicate the tumor, thus improving overall survival rates.

No significant financial relationships to disclose.