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Abstract: Concern over the influence of nanoparticles on human health has risen due to advances in the development of nanotechnology. We are interested in the influence of nanoparticles on the pulmonary system at a molecular level. In this study, gene expression profiling of the rat lung after whole-body inhalation exposure to C60 fullerene (0.12mg/m3; 4.1×104 particles/cm3, 96nm diameter) and ultrafine nickel oxide (Uf-NiO) particles (0.2mg/m3; 9.2×104 particles/cm3, 59nm diameter) as a positive control were employed to gain insights into these molecular events. In response to C60 fullerene exposure for 6h a day, for 4 weeks (5 days a week), C60 fullerene particles were located in alveolar epithelial cells at 3 days post-exposure and engulfed by macrophages at both 3 days and 1 month post-exposures. Gene expression profiles revealed that few genes involved in the inflammatory response, oxidative stress, apoptosis, and metalloendopeptidase activity were up-regulated at both 3 days and 1 month post-exposure. Only some genes associated with the immune system process, including major histocompatibility complex (MHC)-mediated immunity were up-regulated. These results were significantly different from those of Uf-NiO particles which induced high expression of genes associated with chemokines, oxidative stress, and matrix metalloproteinase 12 (Mmp12), suggesting that Uf-NiO particles lead to acute inflammation for the inhalation exposure period, and the damaged tissues were repaired in the post-exposure period. We suggest that C60 fullerene might not have a severe pulmonary toxicity under the inhalation exposure condition. [Copyright &y& Elsevier]

We developed a novel nanocomposite bead system for detection by the naked eye of specific DNA sequences amplified by the polymerase chain reaction (PCR). The DNA probes, which were complementary to the target DNA, are conjugated with the nanocomposite beads. If the amplified products contained sequences complementary to the probes, the beads aggregated through sandwich hybridization. The aggregation was detectable as precipitation of the nanocomposite beads. The results were determined visually and did not require instrumental detection. The assay was sensitive enough to detect PCR products with a detection limit of 10 copies/tube for DNA templates. This technique is that all needed components are included within the initial cap, so that the risk of carryover contamination is very low. The nanocomposite bead system has broad application prospects for the detection of specific DNA sequences in biological and biomedical research. Image 1 • A nanocomposite bead system for specific and highly sensitive detection of DNA sequences. • DNA-conjugated nanocomposite beads precipitated with PCR amplified products. • This naked-eye detection method is highly sensitive, with a limit of detection of 10 copies/tube of the DNA template. [ABSTRACT FROM AUTHOR]

We investigated the responses of microRNAs (miRNAs) using mouse embryonic stem cells (mESCs) exposed to nine chemicals (bis(2-ethylhexyl)phthalate, p -cresol, p -dichlorobenzene, phenol, pyrocatecol, chloroform, tri- n -butyl phosphate, trichloroethylene, and benzene), which are listed as "Class I Designated Chemical Substances" from the Japan Pollutant Release and Transfer Register. Using deep sequencing analysis (RNA-seq), several miRNAs were identified that show a substantial response to general chemical toxicity (i.e., to these nine chemicals considered as a group) and several miRNA biomarkers that show a substantial and specific response to benzene. The functions of the identified miRNAs were investigated in accordance with Gene Ontology terms of their predicted target genes, indicating regulation of cellular processes. We compared the results with those for the long non-coding RNAs (ncRNAs) and mRNAs reported in our previous studies in addition to previously identified miRNAs that are either up- or down-regulated in response to the benzene as stimuli. We also observed that the changes in expression of miRNAs were smaller than those for long ncRNAs and mRNAs. Taken together the current and previous results revealed that toxic chemical stimuli regulate the expression of miRNAs. We believe that the use of miRNAs, including the thus identified miRNAs, as biomarkers contribute to predicting the potential toxicity of particular chemicals or identifying human individuals that have been exposed to chemical hazards. • Investigation of miRNAs expression using mESCs exposed to nine chemicals by RNA-seq. • Identification of novel miRNA biomarkers responsive to general chemical toxicity. • GO analysis reveals the miRNAs affect genes for regulation of cellular processes. • The miRNAs are potentials indicators for chemical stimuli like other reported RNAs. [ABSTRACT FROM AUTHOR]

Background: Excision of the mesopancreas with lymphadenectomy is an important component of pancreatoduodenectomy. However, the optimal extent of lymphadenectomy remains unclear. Furthermore, accurate description of the mesopancreatic lymphatic pathways is difficult, probably because of the complex anatomy. Intestinal derotation simplifies the anatomy and facilitates both examination of lymphatic flow and the surgical procedure. The aim of this study was to evaluate lymphatic flow in the mesopancreas using indocyanine green fluorescence imaging with an intestinal derotation technique, and to clarify the optimal extent of mesopancreas excision and lymphadenectomy in pancreatoduodenectomy., Methods: Indocyanine green solution (2.5 × 10 -3  mg) was injected into the pancreatic head parenchyma. After intestinal derotation, the spread of indocyanine green was observed using near-infrared imaging., Results: Participants comprised 10 patients who underwent pancreatoduodenectomy for periampullary neoplasms. With indocyanine green fluorescence imaging, 9 of the 10 patients showed lymphatic flow from the pancreatic head to the superior mesenteric artery via the inferior pancreaticoduodenal artery and first jejunal artery (but not via the second and more distant arteries), with eventual drainage into the paraaortic region., Conclusions: Lymphatic pathways from the pancreatic head were connected to the superior mesenteric artery via the inferior pancreaticoduodenal artery and first jejunal artery. Excision of the mesopancreas with the inferior pancreaticoduodenal artery and first jejunal artery while preserving the second or more distant arteries appears optimal in pancreatoduodenectomy for periampullary malignancies.

Multi-walled carbon nanotubes (MWCNTs), dispersed in suspensions consisting mainly of individual tubes, were used for intratracheal instillation and inhalation studies. Rats intratracheally received a dose of 0.2 mg, or 1 mg of MWCNTs and were sacrificed from 3 days to 6 months. MWCNTs induced a pulmonary inflammation, as evidenced by a transient neutrophil response in the low-dose groups, and presence of small granulomatous lesion and persistent neutrophil infiltration in the high-dose groups. In the inhalation study, rats were exposed to 0.37 mg/m(3) aerosols of well-dispersed MWCNTs (>70% of MWCNTs were individual fibers) for 4 weeks, and were sacrificed at 3 days, 1 month, and 3 months after the end of exposure. The inhalation exposures delivered less amounts of MWCNTs into the lungs, and therefore less pulmonary inflammation responses was observed, as compared to intratracheal instillation. The results of our study show that well-dispersed MWCNT can produce pulmonary lesions, including inflammation.

IPMN is a slow-growing tumor and has a good prognosis, but is very often associated with a high incidence of pancreatic ductalcarcinoma(DC). Unlike IPMN, DC progresses rapidly, and has a poor prognosis. However, DC concomitant with IPMN has a better prognosis than DC without IPMN. The reason for the good prognosis of the former is undetermined, but perhaps it is the early detection of DC or its not so malignant behavior. It is important to thoroughly examine the entire pancreas for the potentialco -occurrence of DC in patients with IPMN.