Effective dispersal of titanium dioxide nanoparticles for toxicity testing.

Currently, protocols for the dispersal of titanium dioxide (TiO) nanoparticles are not standardized and often yield non-uniform particles and/or insufficient dispersal in liquid medium. Our study aimed to improve dispersal so that TiO nanoparticles are of uniform size, making nanotoxicity testing more reliable. Various combinations of vehicles, sonication durations, and sonication volumes were assessed for optimizing preparations of TiO nanoparticles.

Dose-dependent effects of perinatal hypothyroidism on postnatal testicular development in rat offspring.

The role of thyroid hormones in gonad development remains incompletely understood. We examined the dose-related effects of perinatal hypothyroidism induced by a reversible goitrogen, 6-propyl-2-thiouracil (PTU), on reproductive development in male rat offspring. Timed-pregnant Sprague-Dawley rats were orally administered PTU (0, 0.

Intratracheal instillation methods and the distribution of administered material in the lung of the rat.

Intratracheal instillation is widely used for respiratory toxicity tests in experimental animals. However, there are wide variations in the techniques used for instillation, and it is thus difficult to compare the results obtained using different techniques. To examine the effect of instillation methods, we compared the distribution of a test substance in the lungs of rats after intratracheal instillations under various conditions.

Lack of effects for dietary exposure of bisphenol A during in utero and lactational periods on reproductive development in rat offspring.

The potential for health effects on humans with exposure to bisphenol A (BPA) has raised concerns, and the adverse effects of low-dose exposure to BPA on reproduction have been controversial. The purpose of the present study was to investigate the effects of low-dose exposure to BPA on reproductive development in F(1) rat offspring. Pregnant female Sprague-Dawley rats (F(0)) were fed a diet containing low doses of BPA (0, 0.

Construction of Artificial Hepatic Lobule-Like Spheroids on a Three-Dimensional Culture Device.

One major purpose of cell culture is the reconstruction of physiological structures. Using bovine aortic epithelium cell line HH (JCRB0099) as feeder cells and rat primary hepatocytes, we constructed hepatic lobule-like spheroids on a cell array plate designed for three-dimensional (3D) culture. Microfabricated patterning of the cell array with poly(ethyleneglycol) brushes promotes the formation of spheroids at 100-μm diameter at 100-μm intervals.

Evaluation of exposure risk in the weaving process of MWCNT-coated yarn with real-time particle concentration measurements and characterization of dust particles.

Various applications of multiwalled carbon nanotubes (MWCNT) have been developed. One of these applications is an efficient sheet heating element that is woven from MWCNT-coated yarn. In this research, we assessed the exposure to MWCNT and/or the probability of particle release from broken MWCNT-coated yarn during the weaving process.

Translocation of intratracheally instilled multiwall carbon nanotubes to lung-associated lymph nodes in rats.

In order to assess the extrapulmonary effects of multiwall carbon nanotubes (MWCNT), deposition of MWCNT and histopathologic changes in lung-associated lymph nodes (LALN) were examined in MWCNT-administered rats. At the age of 13 wk, male F344 rats were intratracheally instilled with MWCNT at a dose of 0 (vehicle), 40 or 160 μg/rat. The rats were sacrificed on Day 1, 7, 28 or 91 after instillation and light microscopic examinations were performed on LALN tissues.

Fluoroquinolone antibacterial eye drops: effects on normal human corneal epithelium, stroma, and endothelium.

Background: In vitro studies have suggested the corneal cytotoxicity of third-generation fluoroquinolone levofloxacin (LVFX) and fourth-generation fluoroquinolone moxifloxacin hydrochloride (MFLX) among fluoroquinolone antibacterial eye drops. This study investigated the effects of these two eye drops on the human cornea in vivo.

Methods: We evaluated 30 healthy adults (19 men and 11 women, 38.

Characteristics of multiwall carbon nanotubes for an intratracheal instillation study with rats.

Much concern has been raised over the health consequences of workers exposed to carbon nanotubes. In order to characterize multi-wall carbon nanotubes (MWCNT) suspended in a phosphate-buffered saline containing 0.1% Tween 80 for an intratracheal instillation study.

Dietary exposure to low doses of bisphenol A: effects on reproduction and development in two generations of C57BL/6J mice.

The present study was conducted to examine the effects of low-dose exposure to bisphenol A on reproduction and development in two generations of mice. Pregnant female C57BL/6J mice (F(0)) were fed a diet containing low doses of bisphenol A (0, 0.33, 3.

Testicular development in growth-retarded mice.

To assess delayed fertility in male growth-retarded (grt) mice with congenital primary hypothyroidism, their testes were chronologically examined. The testicular weight in grt mice was significantly lower than age-matched normal mice until 8 weeks but was comparable at 13 and 26 weeks. While normal mice had mature sperm cells in both testes and epididymides at 5 weeks, age-matched grt mice did not.

Identification of a quantitative trait locus regulating B cell-dominant infiltration into autoimmune sialitis lesions of the IQI mouse model of primary Sjögren's syndrome.

Sjögren's syndrome (SS) is caused by an autoimmune sialodacryoadenitis, and up to 5% of patients with SS develop malignant B cell growth. The IQI mouse is a spontaneous model of primary SS in which B cells are the dominant cellular subpopulation among mononuclear infiltrates in sialitis lesions. Understanding the genetic control of aberrant B cell growth in IQI mice may help elucidate the genetic mechanisms involved in B-lineage hyperplasia leading to malignant transformation in human SS.

Increased expression of GRP94 protein is associated with decreased sensitivity to X-rays in cervical cancer cell lines.

Purpose: Radiation therapy is one of the standard treatments for cervical cancer. Glucose regulated protein 94 (GRP94) is a molecular chaperone, which increases in amount after X-ray irradiation. This study examined the involvement of GRP94 in radio-resistance in human cervical cancer cells.

Kinetics of biglycan, decorin and thrombospondin-1 in mercuric chloride-induced renal tubulointerstitial fibrosis.

We investigated the kinetics of decorin, biglycan and thrombospondin-1 in mercuric chloride-treated Brown Norway (BN) rats. BN rats were injected subcutaneously with 1 mg/kg b.w.

Electron microscopic study of subcapsular cell hyperplasia in the adrenal glands of IQI/Jic mice.

Hyperplastic cells in subcapsular cell hyperplasia (SCH) lesion in adrenal glands of female IQI/Jic mice were examined by electron microscopy. These cells were small and polygonal, and had irregular nuclei, elongated mitochondria with lamellar cristae and dense lipid droplets. While these cells showed different features, some of them had desmosomes and basement membranes, and a few round mitochondria with tubular cristae as endocrine cells.

Comparative investigation of several sperm analysis methods for evaluation of spermatotoxicity of industrial chemical: 2-bromopropane as an example.

Reproductive toxicity of 2-bromopropane (2BP), a substitute for ozone layer-depleting chloro-fluorocarbon, was found among the workers in an electronics factory in Korea in 1995. Furthermore the importance of testicular toxicity has been realized since the problem of endocrine disruptors arose all over the world, but manual methods must rely on subjective assessment. Recently, computer-assisted sperm analysis (CASA) was proposed but this system requires vast investment.