ZnO Nanoparticles Induced Caspase-Dependent Apoptosis in Gingival Squamous Cell Carcinoma through Mitochondrial Dysfunction and p70S6K Signaling Pathway.

Zinc oxide nanoparticles (ZnO-NPs) are increasingly used in sunscreens, food additives, pigments, rubber manufacture, and electronic materials. Several studies have shown that ZnO-NPs inhibit cell growth and induce apoptosis by the production of oxidative stress in a variety of human cancer cells. However, the anti-cancer property and molecular mechanism of ZnO-NPs in human gingival squamous cell carcinoma (GSCC) are not fully understood. In this study, we found that ZnO-NPs induced growth inhibition of GSCC (Ca9-22 and OECM-1 cells), but no damage in human normal keratinocytes (HaCaT cells) and gingival fibroblasts (HGF-1 cells). ZnO-NPs caused apoptotic cell death of GSCC in a concentration-dependent manner by the quantitative assessment of oligonucleosomal DNA fragmentation. Flow cytometric analysis of cell cycle progression revealed that sub-G1 phase accumulation was dramatically induced by ZnO-NPs. In addition, ZnO-NPs increased the intracellular reactive oxygen species and specifically superoxide levels, and also decreased the mitochondrial membrane potential. ZnO-NPs further activated apoptotic cell death via the caspase cascades. Importantly, anti-oxidant and caspase inhibitor clearly prevented ZnO-NP-induced cell death, indicating the fact that superoxide-induced mitochondrial dysfunction is associated with the ZnO-NP-mediated caspase-dependent apoptosis in human GSCC. Moreover, ZnO-NPs significantly inhibited the phosphorylation of ribosomal protein S6 kinase (p70S6K kinase). In a corollary in vivo study, our results demonstrated that ZnO-NPs possessed an anti-cancer effect in a zebrafish xenograft model. Collectively, these results suggest that ZnO-NPs induce apoptosis through the mitochondrial oxidative damage and p70S6K signaling pathway in human GSCC. The present study may provide an experimental basis for ZnO-NPs to be considered as a promising novel anti­tumor agent for the treatment of gingival cancer.

IgG4-related disease and lymphocyte-variant hypereosinophilic syndrome: A comparative case series.

OBJECTIVE: To compare the clinical and laboratory features of IgG4-related disease (IgG4-RD) and lymphocyte-variant hypereosinophilic syndrome (L-HES), two rare diseases that often present with lymphadenopathy, gastrointestinal symptoms, eosinophilia, and elevated immunoglobulins/IgE. METHOD: Comparative case series of 31 patients with IgG4-RD and 13 patients with L-HES. RESULTS: Peripheral blood eosinophilia was present in eight of 31 patients with IgG4-RD compared to 13 of 13 patients with L-HES (median eosinophils 0.4 vs 7.0 giga/L, P=.001) and 12 of 20 patients with IgG4-RD had increased serum IgE compared to eight of 13 patients with L-HES, P=.930. Twenty-seven of 30 patients with IgG4-RD had elevated serum IgG4 compared to five of 12 patients with L-HES (median IgG4 9.6 g/L vs 0.80 g/L, P=.002). Flow cytometry demonstrated an aberrant T-cell phenotype in 7 of 23 patients with IgG4-RD and 13 of 13 patients with L-HES (P<.001). T-cell clonality by PCR was positive in 12 of 23 patients with IgG4-RD vs 10 of 13 patients with L-HES (P=.143). Patients in both groups received corticosteroids as first-line therapy. For refractory disease in IgG4-RD, rituximab was the most common steroid-sparing agent, whereas in L-HES, it was pegylated interferon-α-2a. CONCLUSION: The overlapping features of these two diseases with divergent treatment options demonstrate the importance of familiarity with both entities to optimize diagnosis and treatment.

Correlation of cross-sectional diameter with image quality and radiation exposure in MDCT examinations of the neck.

OBJECTIVE: The purpose of this study was to identify an optimal cross-sectional neck diameter that correlates with image quality and radiation exposure in MDCT examinations of the neck performed with automatic tube current modulation. MATERIALS AND METHODS: Ninety-six adults underwent 64-MDCT of the neck with automatic tube current modulation at the same noise setting. On frontal and lateral scout images, maximal body diameters were measured in the transverse and anteroposterior planes at two levels: just below the mandible (upper neck) and at the lung apex (lower neck). Neck diameters were correlated with image quality on a subjective 4-point scale and with radiation exposure (volume CT dose index). RESULTS: As continuous variables, both anteroposterior and transverse diameters in the lower neck were associated with image quality (p ≤ 0.0012). Diameters in the upper neck were not associated with image quality. When diameters in the lower neck were categorized into small, medium, and large, image quality grades were higher for smaller patients (p < 0.001). Images of 81% of small patients (lower neck transverse diameter < 40 cm) had a high image quality grade, compared with images of 7-20% of large patients (diameter > 48 cm). Transverse diameter in the lower neck correlated best with radiation dose measured as volume CT dose index (r = 0.78). When transverse diameter in the lower neck was used to categorize patients' size, the mean volume CT dose index for small patients was 34.1 mSv and that for large patients was 63.5 mSv. CONCLUSION: Lower neck transverse diameter on the CT scout image best correlates with image quality and radiation exposure for neck MDCT examinations performed with automatic tube current modulation. Images of patients with a lower neck transverse diameter less than 40 cm are of higher quality than those of larger patients. Individualized dose reduction techniques therefore may be appropriate for smaller patients.

Characteristics and treatability of oil-bearing wastes from aluminum alloy machining operations.

Enomoto Industry Co., exclusively uses water-based cutting fluids in its aluminum alloy machining operations. Since the cost of disposal can be much greater than the cost of purchase, the treatability of spent cutting fluids is becoming a major criterion for cutting fluid selection. Samples were collected from the machining lines at Enomoto's facility to determine their characteristics and evaluate their treatability with centrifugation, chemical coagulation and electrochemical coagulation. As expected, oil and grease (O&G) and total suspended solids (TSS) are the main reasons that spent cutting fluids are prohibited from being discharged into local swage systems. The average O&G found in the spent cutting fluids is 87,354 mg/L with TSS of more than 70,000 mg/L. Both O&G and TSS are the major contributors to the high turbidity of these waste effluents. A centrifuge with a relative centrifugal force of 1318 x g, was able to reduce 60% of the turbidity. By adding the coagulant aluminum chloride, the oil-water emulsion was destabilized, and the turbidity was reduced from 3249 Formazin Attenuation Units (FAU) to around 314 FAU. With freshly generated aluminum ions in the spent cutting fluid, the electrochemical process destabilized the oil-water emulsion system. The coalesced oil droplets were adsorbed onto the highly dispersed aluminum coagulant. The oil-rich sludge that was generated in the operation was then floated to the surface, forming a blanket that was removed by skimming. The electrochemical treatment was able to reduce the turbidity to less than 14 FAU, which is the detection limit of the Hach DR/4000 UV-vis spectrophotometer.

The prevalence and risk factors analysis of serum antibody to hepatitis C virus in the elders in northeast Taiwan.

BACKGROUND: Hepatitis C virus (HCV) infection will result in liver cirrhosis and hepatocellular carcinoma, which are the leading causes of death in Taiwan. The prevalence of antibody to HCV (anti-HCV) was 2%-3% in Taipei city. However, it can be as high as 20% to 60% in Central and Southern part of Taiwan. In I-Lan, a county located in northern-east Taiwan, there is no large-scale investigation yet. The objective of this research is to evaluate the prevelance and risk factors of anti-HCV positivity in three towns of I-Lan county. METHODS: Blood sampled from people in San-Shing, Tou-Cheng and Tong-Shan was collected from October 1999 to June 2000. Totally, 1,316 persons (607 male, 790 female, mean age: 62 +/- 12 years old) were enrolled. Anti-HCV was measured by a second-generation enzyme immunoassay. Risk factors analysis was performed in anti-HCV positive subjects and age-sex matched anti-HCV negative controls. RESULTS: Sixty-seven persons (5.1%) had positive serum anti-HCV. The prevalence rate of anti-HCV increased with age. San-Shing and Tong-Shan showed a higher anti-HCV prevalence rate than Tou-Cheng (6.0% and 8.3% vs. 3.2%, p = 0.007). Risk factors analysis showed that people with positive serum anti-HCV had a significantly high rate of surgical history, usage of nondisposable needles injection, frequent nondisposable needles injection, frequent dental therapy, and a lower level of education than the anti-HCV negative counterpart (p < 0.05). Multivariate logistic regression analysis revealed that age > 60 years, surgical history and frequent nondisposable needles injection were significantly independent risk factors of positive anti-HCV (p < 0.05). CONCLUSIONS: The prevalence rate of anti-HCV in I-Lan county was 5.1%. Age > 60 years, surgical history and frequent nondisposable needles injection were the significant risk factors of HCV infection in I-Lan area.