Protective effects of tauroursodeoxycholate against radiation-induced intestinal injury in a mouse model.

In patients with high-level radiation exposure, gastrointestinal injury is the main cause of death. Despite the severity of damage to the gastrointestinal tract, no specific therapeutic option is available. Tauroursodeoxycholic acid (TUDCA) is a conjugated form of ursodeoxycholic acid that suppresses endoplasmic reticulum (ER) stress and regulates various cell-signaling pathways. We investigated the effect of TUDCA premedication in alleviating intestinal damage and enhancing the survival of C57BL/6 mice administered a lethal dose (15Gy) of focal abdominal irradiation. TUDCA was administered to mice 1 h before radiation exposure, and reduced apoptosis of the jejunal crypts 12 h after irradiation. At later timepoint (3.5 days), irradiated mice manifested intestinal morphological changes that were detected via histological examination. TUDCA decreased the inflammatory cytokine levels and attenuated the decrease in serum citrulline levels after radiation exposure. Although radiation induced ER stress, TUDCA pretreatment decreased ER stress in the irradiated intestinal cells. The effect of TUDCA indicates the possibility of radiation therapy for cancer in tumor cells. TUDCA did not affect cell proliferation and apoptosis in the intestinal epithelium. TUDCA decreased the invasive ability of the CT26 metastatic colon cancer cell line. Reduced invasion after TUDCA treatment was associated with decreased matrix metalloproteinase (MMP)-7 and MMP-13 expression, which play important roles in invasion and metastasis. This study shows a potential role of TUDCA in protecting against radiation-induced intestinal damage and inhibiting tumor cell migration without any radiation and radiation therapy effect.

Optimization of Ultrasound-Assisted Pretreatment for Accelerating Rehydration of Adzuki Bean (Vigna angularis).

Adzuki bean (Vigna angularis), which provides plant-based proteins and functional substances, requires a long soaking time during processing, which limits its usefulness to industries and consumers. To improve this, ultrasonic treatment using high pressure and shear force was judged to be an appropriate pretreatment method. This study aimed to determine the optimal conditions of ultrasound treatment for the improved hydration of adzuki beans using the response surface methodology (RSM). Independent variables chosen to regulate the hydration process of the adzuki beans were the soaking time (2-14 h, X1), treatment intensity (150-750 W, X2), and treatment time (1-10 min, X3). Dependent variables chosen to assess the differences in the beans post-immersion were moisture content, water activity, and hardness. The optimal conditions for treatment deduced through RSM were a soaking time of 12.9 h, treatment intensity of 600 W, and treatment time of 8.65 min. In this optimal condition, the values predicted for the dependent variables were a moisture content of 58.32%, water activity of 0.9979 aw, and hardness of 14.63 N. Upon experimentation, the results obtained were a moisture content of 58.28 ± 0.56%, water activity of 0.9885 ± 0.0040 aw, and hardness of 13.01 ± 2.82 g, confirming results similar to the predicted values. Proper ultrasound treatment caused cracks in the hilum, which greatly affects the water absorption of adzuki beans, accelerating the rate of hydration. These results are expected to help determine economically efficient processing conditions for specific purposes, in addition to solving industrial problems associated with the low hydration rate of adzuki beans.

Comparison of the pretreatment methods for enhancing hydration of water-soaked adzuki beans (Vigna angularis).

Five pretreatments methods, cold plasma, pressure drop, heating, and bath-type and probe-type sonications were compared to shorten the rehydration process of adzuki bean (Vigna angularis) soaked before the cooking in terms of the hydration and softening efficacies. Moisture content and water activity of the probe-type sonicated beans were most dramatically increased as 11-45% and 0.59-0.97 after soaking for only 2 h, respectively (non-treated: 11-12% and 0.59-0.66). Accordingly, the probe-type sonicated beans were most rapidly softened as 27-5 N in the 2 h-soaking and exhibited the lowest hardness after soaking/cooking as ~ 0.97 N (non-treated: 27-21 N and ~ 5.5 N, respectively). According to scanning electron micrographs, these results can be attributed to formation of prominent fissures or scars in the hilum of the probe-type sonicated beans. Consequently, this study will be provide valuable information for developing a rational process in food industry to shorten the rehydration of the adzuki beans.

EFFECT OF ABDOMINAL IRRADIATION IN MICE MODEL OF INFLAMMATORY BOWEL DISEASE.

Inflammatory bowel diseases could be diagnosed in major measure by diagnostic imaging; however, radiation exposure in the intestine may also contribute to the progression of these pathologies. To better understand the impact of radiation in the presence of bowel disease, we administered dextran sodium sulfate (DSS) to C57BL/6 mice to induce colitis and exposed to radiation at abdominal area. We observed that abdominal irradiation (13 Gy) aggravates the DSS-induced decrease in survival rate (0%), body weight (74.54 ± 3.59%) and colon length (4.98 ± 0.14 cm). Additionally, abdominal irradiation markedly increased in colonic inflammation levels (3.16 ± 0.16) compared with that of DSS-induced sham mice. Furthermore, abdominal irradiation also increased the mRNA expression levels of inflammatory genes, such as cyclooxygenase-2 (13.10 folds), interleukin-6 (48.83 folds) and tumor necrosis factor-alpha (42.97 folds). We conclude that abdominal irradiation aggravates the detrimental effects of DSS-induced colitis in mice, which might be a useful guideline for inflammatory bowel disease patients.

Investigation of the Localized Corrosion and Passive Behavior of Type 304 Stainless Steels with 0.2⁻1.8 wt % B.

The pitting corrosion resistance and passive behavior of type 304 borated stainless steels (Febalance⁻18Cr⁻12Ni⁻1.5Mn⁻(0.19, 0.78, and 1.76 wt %)B) manufactured through conventional ingot metallurgy were investigated. The alloys were composed of an austenitic matrix and Cr2B phase, and the volume fraction of Cr2B increased from 1.68 to 22.66 vol % as the B content increased from 0.19 to 1.76 wt %. Potentiodynamic polarization tests measured in aqueous NaCl solutions revealed that the pitting corrosion resistance was reduced as the B content increased and the pits were initiated at the matrix adjacent to the Cr2B phase. It was found that the reduced resistance to pitting corrosion by B addition was due to the formation of more defective and thinner passive film and increased pit initiation sites in the matrix.

A microfluidic device for label-free detection of Escherichia coli in drinking water using positive dielectrophoretic focusing, capturing, and impedance measurement.

While sensors that allow for high-throughput enumeration of microorganisms within drinking water are useful for water quality monitoring, it is particularly challenging to accurately quantify microorganisms that are present in low numbers (<100 CFU/mL) in a high-throughput manner. Negative dielectrophoresis (nDEP) is typically utilized in DEP-based cell focusing methods; however, due to its low conductivity, drinking water cannot be analyzed by this approach. Here, we report a positive DEP (pDEP)-based Escherichia coli detection system that is integrated with a focusing and sensing electrode. By incorporating a passivation layer, we avoided issues with adhesion of E. coli to the electrode, and achieved efficient cell focusing under high flow rate conditions (1500 µL/h). The resulting focused E. coli cells were then trapped on the sensor electrode, resulting in changes in impedance. The proposed system was evaluated using four different E. coli populations (150-1500 CFU/mL). We successfully enumerated populations as low as 300 CFU/mL within 1 min, and the signal variation was 1.13±0.37%. The device introduced in this study provides the basis for the development of portable, highly sensitive microorganism sensors that enable rapid detection of bacteria in drinking water.

In vitro evaluation of Cordyceps militaris as a potential radioprotective agent.

Radiation is an important component of therapy for a wide range of malignant conditions. However, it triggers DNA damage and cell death in normal cells and results in adverse side-effects. Cordyceps militaris (C. militaris), a traditional medicinal mushroom, produces the bioactive compound, cordycepin (3'-deoxyadenosine) and has multiple pharmacological activities, such as antitumor, antimetastatic, antioxidant and immunomodulatory effects. The present study was undertaken to investigate whether CM-AE, an extract obtained from C. militaris exerts protective effects against radiation-induced DNA damage. The protective effects of CM-AE were compared with those of cordycepin. CM-AE effectively increased free radical scavenging activity and decreased radiation-induced plasmid DNA strand breaks in in vitro assays. CM-AE significantly inhibited the generation of reactive oxygen species (ROS) and cellular DNA damage in 2 Gy irradiated Chinese hamster ovary (CHO)-K1 cells. Moreover, treatment with CM-AE induced similar levels of phosphorylated H2AX in the cells, which reflects the initial DNA double-strand breaks in the irradiated cells compared with the non-irradiated CHO-K1 cells. However, cordycepin did not show free radical scavenging activity and did not protect against radiation-induced plasmid DNA or cellular DNA damage. These results suggest that the free radical scavenging activity of CM-AE contributes towards its DNA radioprotective effects and that the protective effects of CM-AE are much more potent to those of cordycepin. The data presented in this study may provide useful information for the screening of potent radioprotective materials.

In vitro and in vivo protective effects of granulocyte colony-stimulating factor against radiation-induced intestinal injury.

Intestinal injury is a major cause of death after high-dose radiation exposure. The use of granulocyte-colony stimulating factor (G-CSF) to treat radiation injury has focused on enhancing recovery from hematopoietic radiation syndrome. We evaluated G-CSF for its ability to protect against radiation-induced intestinal injury in rat intestinal epithelial cells (IEC-6) and BALB/c mouse models. For in vitro tests, pre-radiation addition of G-CSF to IEC-6 prevented cytotoxicity and the loss of cell viability. Pre-radiation G-CSF treatment also reduced radiation-induced cleavage of caspase-3 and p53 in IEC-6. For in vivo tests, examination 12 h after abdominal irradiation showed that G-CSF-treated mice were protected against apoptosis of the jejunal crypts. G-CSF-treated mice also showed attenuated intestinal morphological changes 3.5 days after abdominal radiation (10 Gy). G-CSF also reduced the levels of proinflammatory cytokines interleukin-6 and tumor necrosis factor-α after radiation. This study showed that G-CSF may protect against radiation-induced intestinal damage through its anti-apoptotic and anti-inflammatory effects. These results suggest that G-CSF is promising candidate for protection against intestinal mucosal injury following irradiation.

Filiform polyposis in the sigmoid colon: a case series.

Filiform polyposis is a rare condition of uncertain pathogenesis that is usually found in association with Crohn's disease, ulcerative colitis, intestinal tuberculosis or histiocytosis X. We report seven interesting cases of polyposis with various pathologic components, mainly located in the left side of the colon with no associated inflammatory bowel disease, intestinal tuberculosis or histiocytosis X. Multiple finger-like polypoid lesions with the appearance of stalactites were noted on the left side of the colon, especially in the sigmoid area, at the time of colonoscopy. The polyps had a variety of sizes and shapes and were shown to have various histopathologic components among the different patients. Although filiform polyposis localized in the sigmoid colon appears not to have high oncogenic potential, periodic follow-up seems to be needed.