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For stringent regulations of exhaust gases from gasoline-powered vehicles, small amount of platinum-group metals (PGMs) in automotive catalysts is highly required. To satisfy this requirement, applications of base-metal catalysts such as Fe and Mn have been vigorously discussed and investigated. Previously, we reported that rare earth metals containing hexagonal Fe and Mn oxides work as effective support materials and active species in CO oxidation, C3H6 oxidation, and NO reduction. However, most of the base-metal oxides could be readily decomposed by gasoline engine aging at approximately 1000 °C. In this study, we show that hexagonal YbMnO3 (h-YbMnO3) can be obtained as single-phase using the simple coprecipitation method with H2O2. Moreover, h-YbMnO3 can function as a oxygen storage material, which maintains its hexagonal structure after hydrothermal aging at 1000 °C for 25 h owing to the small ionic radius of Yb. On the other hand, isostructural YMnO3 (h-YMnO3) can be easily decomposed under the same aging condition. The catalytic performances of Pd loaded materials (Pd/h-YbMnO3, Pd/Al2O3, and Pd/CeO2-ZrO2 (CZ)) on cordierite honeycomb substrates were evaluated. Among them, Pd/h-YbMnO3 exhibited the highest oxidation activities even though it had significantly lower specific surface area (SSA). In particular, Pd/h-YbMnO3 exhibits a strong effect on paraffin oxidation such as C3H8, which is less reactive than other olefinic and aromatic hydrocarbons for automotive catalysts. [ABSTRACT FROM AUTHOR]

Highlights: [•] Novel compounds 2-methyl-3-[2-chloro (or 3-chloro)phenylthio]-1,4-naphthalenedione were successfully synthesized. [•] Solid-state color of these compounds can be changed according to the position of chloro group in phenylthio ring. [•] Crystal structures of these compounds were appeared by X-ray crystallographic analyses. [ABSTRACT FROM AUTHOR]

In rice fields, the cultivation area itself can play an essential role as a habitat for wetland organisms. Many previous studies showed negative impact of agricultural intensification and abandonment on biodiversity in wet farmland ecosystems. However, verification of the direct impact of aquatic environmental change by the paddy improvement and abandonment still remains. Here, we investigated the effects of the intensification and abandonment on the area of wet fields remaining in paddies during the fallow season, as well as the factors driving the population decline of the Japanese brown frog ( Rana japonica ), using data of long-term monitoring numbers of egg masses at multiple sites. To quantitatively estimate the spatial and temporal variation in saturated areas with water in the paddies where the frogs spawn in early spring, we used infrared bands of Landsat images. Both paddy improvements and abandonment have affected R. japonica populations through the reduction of wet areas in the fields. Furthermore, the frog's population size was positively associated with the area of surrounding forest. Our findings suggest that conservation in wet farmland requires appropriate water management inside the cultivation area as well as in other landscape elements that serve as secondary habitats. [ABSTRACT FROM AUTHOR]

Molasses wastewater contains high levels of organic compounds, cations, and anions, causing operational problems for anaerobic biological treatment. To establish a high organic loading treatment system for industrial molasses wastewater, this study designed a combined system comprising an acidification tank, a thermophilic multi-stage (MS)-upflow anaerobic sludge blanket (UASB) reactor, mesophilic UASB reactor, and down-flow hanging sponge reactor. The average total chemical oxygen demand (COD) and biochemical oxygen demand removal rates were 85% ± 3% and 95% ± 2%, respectively, at an organic loading rate of 42 kgCOD cr m −3 d −1 in the MS-UASB reactor. By installation of the acidification tank, the MS-UASB reactor achieved low H 2 -partial pressure. The abundance of syntrophs such as fatty acid-degrading bacteria increased in the MS-UASB and 2nd-UASB reactors. Thus, the acidification tank contributed to maintaining a favorable environment for syntrophic associations. This study provides new information regarding microbial community composition in a molasses wastewater treatment system. [ABSTRACT FROM AUTHOR]

Delafossite-type solid solution, CuFe1-xAlxO2, was synthesized and its oxygen storage capacity (OSC) was investigated under oxidation/reduction cycle using a pulse injection method. CuFe1-xAlxO2 was synthesized by heating at 1100-1150 °C in N2 flow. OSC values for x = 0.1 and 0.3 were larger than that for x = 0 above 500 °C, indicating that substitution of Fe3+ by Al3+ improved OSC. For x = 0.5-1.0, temperature at which OSC increased steeply shifted upward. Results of X-ray diffraction (XRD) after the thermogravimetry and differential thermal analysis (TG-DTA) measurement in air for CuFe1-xAlxO2 ( x = 0-0.7) indicated that oxidative decomposition of delafossite phases to CuO and spinel-type phase occurred. In addition, Cu reduction temperature estimated by the temperature programmed reduction using H2 (H2-TPR) shifted to higher temperature with increasing Al content. The XRD results of the samples after H2 and O2/He pulse injection suggested that the oxygen storage/release behavior was caused by reversible oxidation/reduction process between CuFe1-xAlxO2 delafossite and (Fe1-xAlx)3O4 spinel phase +Cu. [ABSTRACT FROM AUTHOR]

Abstract: Three types of supramolecular benzoheterocyclic host complexes were successfully prepared using (1R,2S)-2-amino-1,2-diphenylethanol and three types of benzoheterocyclic (benzothiophene, benzofuran, and benzopyrrole) acid derivatives. The host complexes had one-dimensional (1D) channel-like cavities that were formed by the assembly of two-component 21-helical columnar network structures, which included guest alcohol molecules. The release behavior of the guest molecules could be tuned by the type of heterocyclic ring in the supramolecular host complex. [Copyright &y& Elsevier]

Abstract: Delafossite-type CuLnO2 (Ln = La, Y) was synthesized and investigated their oxygen storage capacity (OSC) under oxidation/reduction cycle. CuLaO2 was synthesized by heating at 1000 °C for 6 h in N2 flow and CuYO2 was synthesized by heating of Cu2Y2O5 at 1190 °C for 1 h in N2 flow. The oxygen storage capacity values of CuLaO2 and CuYO2 at lower temperature were larger than that of CeO2-based materials which is used as a promoter of an automobile catalyst. The stability of delafossite-type CuLnO2 under cyclic oxidation/reduction atomosphere was investigated using XRD analysis. During the OSC measurement up to 700 °C, CuLaO2 decomposed to La2CuO4 and Cu2O. CuYO2 also partially decomposed to Y2O3, Cu2Y2O5 and Cu2O. These results suggest that oxidative decomposition of CuLnO2 occurred at high temperature. In lower temperature range, delafossite-type CuLaO2+x containing excess oxygen existed in both oxidative and reductive atmosphere and it partially decomposed during a hundred of oxidation/reduction cycles. [Copyright &y& Elsevier]

A(PO)(OH) (A = Ca and Sr)-supported Pt catalysts were prepared and their catalytic activity in NO reduction were investigated. The Sr(PO)(OH)-supported catalyst had high catalytic activity in the CH-NO-O reaction; the activity was higher than that of the γ-AlO-supported catalyst at 300 °C. The basicity of the apatite supports would affect the chemical state of Pt on catalyst, resulting in promotion of NO reduction. [ABSTRACT FROM AUTHOR]

Abstract: Apatite-type silicate (La8A2Si6O26 (A=Ca, Sr, Ba)) supported Pt catalysts were prepared and their catalytic activities were investigated for NO reduction. La8A2Si6O26 were obtained by the sol–gel method. Pt/La8A2Si6O26 (A=Ca, Sr, Ba) catalysts loaded with 1mass% of Pt were prepared by the impregnation method. The maximum NO conversions for C3H6–NO–O2 reaction over Pt/La8A2Si6O26 catalyst were 37%, 41% and 50% for A=Ca, Sr and Ba, respectively. The reduction properties of Pt on the catalysts were evaluated by temperature programmed reduction (TPR). The composition of the apatite-type support affected the reduction property of Pt on the catalyst, resulting in promotion of catalytic activity for C3H6–NO–O2 reaction below 300°C. [Copyright &y& Elsevier]

Abstract: There is growing evidence of mitochondrial membrane raft-like microdomains that are involved in the apoptotic pathway. The aim of this study was to investigate the effect of methyl-beta-cyclodextrin (MβCD), being a well-known lipid microdomain disrupting agent and cholesterol chelator, on the structure and bioenergetics of rat liver mitochondria (RLM). We observed that MβCD decreases the function of RLM, induces changes in the mitochondrial configuration state and decreases the calcium chloride-induced swelling. These data suggest that disruption of mitochondrial raft-like microdomains by cholesterol efflux on one hand impairs mitochondrial bioenergetics, but on the other hand it protects the mitochondria from swelling. [ABSTRACT FROM AUTHOR]

Abstract: Delafossite-type CuMO2 (M: trivalent cation) compounds were synthesized and found to exhibit oxygen storage capacity under oxidation/reduction cycle. The oxygen storage capacity values of CuFeO2 and CuMnO2 at lower temperature were larger than those of CuAlO2, CuGaO2- and CeO2-based materials. The large OSC includes an oxygen uptake at low temperature attributed to formation of metallic Cu by decomposition of the delafossite phase for CuFeO2 and CuMnO2. In the case of CuAlO2, which remained without decomposition below 800°C, the oxygen uptake increased with temperature up to 0.13mol-O/mol-CuMO2. The stability of the delafossite-type CuMO2 against oxidation/reduction cycle is affected by M3+. In this study, it was found that the oxygen storage behavior of CuMO2 can be controlled by a combination of Cu and M ions. [Copyright &y& Elsevier]

Apatite-type silicate supported precious metal catalysts were prepared and investigated for their catalytic activity in selective catalytic NO reduction. Single-phase La9.33Si6O26 and La8.33ASi6O25.5 (A = Ca, Sr, Ba) were obtained by a sol–gel method. Pd/La9.33Si6O26 catalyst exhibited high activity for oxidation of C3H6, comparable to Pd/Al2O3 catalyst, although the specific surface area of La9.33Si6O26 was lower than that of Al2O3. In addition, Pt/La9.33Si6O26 catalyst exhibited higher activity for selective catalytic reduction of NO than Pt/Al2O3 catalyst. Substitution of Ba2+ for La3+ of La9.33Si6O26 led to increased catalytic activity at low temperature. [ABSTRACT FROM AUTHOR]

Abstract: The new numerical marine ecosystem model has been developed to establish an optimum management plans for sustainable aquaculture in estuaries. This model was applied to Lake Saroma, which is the third largest brackish lake and one of the major sources of aquacultured scallops in Japan. In this study, the pelagic ecosystem model, the benthic ecosystem model and the scallop growth model were integrated comprehensively. This model is remarkable for two features. Firstly, the farming cycle in this area was considered in detail. This was achieved by dividing the aquacultured scallops into three compartments according to their age; each compartment having two state variables, biomass and number of individuals. This feature, called the Generation-tracing type model, made it possible to evaluate weight changes of scallops for each generation. Consequently, simulated results of scallop weights showed good accordance with the measurements. Secondly, the amount of released nutrients from the sediment was evaluated using a vertical diffusive equation with simultaneous mineralization processes in sediment. To evaluate the amount, the interaction between the pelagic and benthic systems, which is generally a very important factor in enclosed water, was modeled. This structure provided the model with an ability to predict future water quality and production of scallops with sediment changes. At the next stage of the study, we applied this model to compare scenarios for future management. Preliminary results showed that a larger number of cultured scallops would result in a smaller average scallop size and worse water quality because of sediment degradation due to the increased deposit of scallop feces. [Copyright &y& Elsevier]

Abstract: Apoptosis is induced not only during morphogenesis and embryogenesis but also under various pathological conditions, especially related to oxidative stress. Apoptotic cells are phagocytized by neighboring cells while necrotic cells cause local and general reactions sometimes lethal to our bodies. Data have been accumulated to demonstrate that the switch of the cell death mode from apoptosis to necrosis does occur. However, detailed mechanisms involved in the switch mechanism remain unsolved although decreases in the intracellular level of ATP and a burst in the cellular level of reactive oxygen species (ROS) have been proposed. Recently, we have shown that the population of apoptotic cells reaches maximum in human osteosarcoma 143B cells treated for 6h with menadione (MEN) while necrotic cells become predominant at 9h of the treatment. In the present study we have attempted to clarify the role of cellular ATP in the switch mechanism using ρ 0 cells derived from human osteosarcoma ρ + cells. Results are summarized as follows: (1) Apoptotic and necrotic changes in ρ 0 cells are much faster than ρ + cells after the treatment with MEN. (2) Cellular level of ATP in ρ 0 cells remains essentially in the same level before and after the MEN-treatment while intracellular levels of superoxide continuously increase after the MEN-treatment. (3) ρ + cells treated with MEN in the presence of antimycin A plus oligomycin show similar changes to those of MEN-treated ρ 0 cells. (4) MEN-induced increases in the cellular level of superoxide are distinctly suppressed by inhibitors of NADPH oxidase. These results suggest that the intracellular level of superoxide may be a key factor directly related to the switch mechanism from apoptosis to necrosis, and that decreases in cellular level of ATP accelerate both apoptotic and necrotic changes of the cells. [Copyright &y& Elsevier]

Nucleated trout erythrocytes under oxidative stress suffer DNA membrane damage and inactivation of glutathione peroxidase. In addition, oxidative damage increases with the age of the cell. In the present paper, we evaluate the effects of oxidative stress and ageing on mitochondrial functionality by means of transmission electron microscopy and cytofluorimetric determination of mitochondrial membrane potential and intracellular levels of reactive oxygen species. The protective activity of the antioxidant organoselenium compound ebselen, a mimic of glutathione peroxidase, is also evaluated. Ebselen prevents the drastic structural and functional changes in mitochondria in aged RBCs induced by oxidative stress. However, the antioxidant does not prevent swelling of the mitochondria. [Copyright &y& Elsevier]

Leflunomide (LFM) is an inhibitor of mitochondrial enzyme dihydroorotate dehydrogenase (DHODH) that catalyzes the conversion of dihydroorotate to orotate coupled with the generation of reactive oxygen species (ROS) from mitochondria. We demonstrate here that LFM causes an unrestrained proliferation of mitochondria both in human osteosarcoma cell line 143B cells and rat liver derived RL-34 cells. Increases in the total mass of mitochondria per cell in LFM-treated cells were evidenced by the application of Green FM or 10-n-nonyl acridine orange to flow cytometry, an enhanced replication of mtDNA and electron microscopy. Externally added uridine improved the disturbance in cell cycle progression in LFM-treated cells, but failed to suppress such unrestrained mitochondrial proliferation. On the contrary, lapacol and 5-fluoroorotate, inhibitors of DHODH besides LFM, suppressed the biogenesis of mitochondria during the cell cycle progression. LFM, but not lapacol or 5-fluoroorotate, caused increases of the intracellular level of acetylated α-tubulin. These data suggest that the inhibition of DHODH may not be at least primarily related to the LFM-induced abnormal proliferation of mitochondria, and support our recent published observation that changes in the physicochemical properties of microtubules may be in someway concerned with the biogenesis of mitochondria. [Copyright &y& Elsevier]

Background: This study aimed to report an aortic pseudoaneurysm, a rare but lethal complication, after a spinal fracture in ankylosing spine., Observations: An 83-year-old obese woman presented with dementia and was nonambulatory after a fall. She was transported to the hospital, and imaging showed a hyperextension-type L1 fracture with diffuse idiopathic skeletal hyperostosis (DISH). After posterior fusion surgery using percutaneous pedicle screws, screw loosening was detected 10 days postoperatively. Fracture dislocation was reduced by changing to transdiscal screws and rodding while in the lateral position. However, the anterior opening persisted. Enhanced computed tomography performed at 6 weeks postoperatively showed a large aortic pseudoaneurysm extending into the vertebral fracture site without screw loosening. Neither endovascular aortic repair nor open surgery was applicable. The patient was transferred to a sanatorium and died of pneumonia 5 months postoperatively without aortic aneurysm rupture., Lessons: An aortic pseudoaneurysm can occur in hyperextension-type spinal fractures in DISH, even after fusion surgery, when the edge of the fracture is in contact with the aortic wall. The anterior opening dislocation should be reduced as much as possible.

Introduction: Curative resection generally has a good prognosis if the tumor is a locally advanced colorectal tumor. However, resection of a primary tumor that has invaded the aortoiliac artery is controversial. Herein, we report a case of successful resection of advanced cecal cancer invading the external iliac artery., Case Report: A 29-year-old male patient had advanced cecal cancer invading the right external iliac artery and vein, right ureter, iliopsoas muscle, and sigmoid colon. We collected the patient's pre-/intra-/postoperative, clinical, and histological data. We reviewed the factors that may have contributed to curative resection without complications. We performed a palliative terminal ileum-sigmoid anastomosis for the prevention of intestinal obstruction. The patient received neoadjuvant chemotherapy, and the tumor patently regressed. After arterial reconstruction was performed with a femoral-femoral bypass, we performed radical resection: right hemicolectomy; partial sigmoidectomy; and partial resection of the right ureter, iliopsoas muscle, right testicular, and external iliac vessels. Pathologically, 99% of the tumor cells disappeared after chemotherapy. The patient was discharged on postoperative day 9. No recurrence has been noted 24 months after surgical resection, and the patient is receiving adjuvant chemotherapy., Conclusions: Thus, we successfully resected advanced cecal cancer without complications. Reconstruction with femoral-femoral arterial bypass and neoadjuvant chemotherapy are useful methods for curative resection without complications., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Although the efficacy of thoracic endovascular aortic repair( TEVAR) for blunt thoracic aortic injury (BTAI) has been reported, the determination of the proper endograft size for TEVAR in BTAI cases is yet to be established. The management of BTAI by TEVAR may not be effective if a wrong endograft size is selected, possibly leading to fatal outcomes. In this case report, a hemodynamically unstable patient with BTAI was saved by TEVAR, and the preoperative and postoperative changes in the aortic diameter were compared. In TEVAR for BTAI, the effects of hemodynamic instability should be considered and the appropriate device size should be determined based on blood pressure, pulse, and inferior vena cava diameter.

A 57-year-old woman with Marfan syndrome had undergone the surgical treatment for pectus excavatum at 15 years of age. She had since been screened regularly by computed tomography(CT) to detect any vascular diseases. CT demonstrated a left subclavian arterial aneurysm at 55 years of age. It enlarged to a diameter of 32 mm, and surgical treatment was performed. The subclavian artery and the aneurysm were identified by echography in order to locate the exact sites of supraclavicular and subclavicular skin incisions. The subclavian artery aneurysm was resected without dividing the clavicle, and replaced by a vascular graft. Echography is useful for precisely locating a subclavian artery aneurysm, which enables feasible resection without dividing the clavicle.

Glutaric aciduria type II (GAII) is a rare inborn error of metabolism clinically classified into a neonatal-onset form with congenital anomalies, a neonatal-onset form without congenital anomalies and a mild and/or late-onset form (MIM #231680). Here, we report on a GAII patient carrying a homozygous novel c.143_145delAGG (p.Glu48del) mutation in the ETFB gene, who presented with a neonatal-onset form with congenital anomalies and rapidly developed cardiomegaly after birth.

We carried out a retrospective evaluation of the early and mid-term outcomes of aortic valve replacement (AVR) for aortic stenosis in hemodialysis patients. Between 2004 and 2012, a total of 40 dialysis patients underwent AVR with or without an additional procedure. Hemodialysis was performed routinely the day before and during the operation. At surgery, decalcification was performed using a cavitron ultrasonic surgical aspirator(CUSA) and a high performance mechanical valve was then implanted, with the exception of elderly patients or those in whom use of oral anticoagulation is contraindicated. A mechanical valve was used in 33 patients and a bioprosthetic valve in 7 patients. Hemodialysis was resumed on the 2nd postoperative day in the majority of patients. There was no intra-operative death and in-hospital mortality was 5%, due to sepsis and intestinal ischemia in 2 of the 40 patients. The mean follow-up period was 33 months. There was no structural valve deterioration in patients with the bioprosthetic valve. Of the 8 late deaths, the reason for deaths was cardiac in 4 patients. Overall survival in the 40 patients was 92%, 79%, and 54% at 1, 3, and 5 years, respectively. Our study demonstrated good early and mid-term outcomes for aortic valve replacement in hemodialysis patients. CUSA was useful for patients with a calcified valve and annulus. A bioprosthetic valve was acceptable for use in elderly patients.

Osteosarcoma is one of the most malignant tumors of childhood and adolescence that is often resistant to standard chemo- and radio-therapy. Geldanamycin and geldanamycin analogs have been recently studied as potential anticancer agents for osteosarcoma treatment. Here, for the first time, we have presented novel anticancer mechanisms of geldanamycin biological activity. Moreover, we demonstrated an association between the effects of geldanamycin on the major heat shock proteins (HSPs) and the overall survival of highly metastatic human osteosarcoma 143B cells. We demonstrated that the treatment of 143B cells with geldanamycin caused a subsequent upregulation of cytoplasmic Hsp90 and Hsp70 whose activity is at least partly responsible for cancer development and drug resistance. On the other hand, geldanamycin induced upregulation of Hsp60 gene expression, and a simultaneous loss of hyperacetylated Hsp60 mitochondrial protein pool resulting in decreased viability and augmented cancer cell death. Hyperacetylation of Hsp60 seems to be associated with anticancer activity of geldanamycin. In light of the fact that mitochondrial dysfunction plays a critical role in the apoptotic signaling pathway, the presented data may support a hypothesis that Hsp60 can be another functional part of mitochondria-related acetylome being a potential target for developing novel anticancer strategies.

Objectives: The purpose of the present study is to assess the clinical results of aortic root replacement using the Carbo-Seal composite graft( CS) compared with the other type of homemade composite grafts. Fifty-nine patients who underwent aortic root replacement between January 1998 to December 2010 were retrospectively analyzed. Twenty-six received homemade composite graft( group 1;1998 ~ 2005) and 33 received CS( group 2;2005 ~ 2010)., Results: The duration of operation was longer in group 1:469.2±143.5 min versus 380.3±153.9 min (p=0.03). Although there was no statistically significant difference, group 2 had a higher complex operation rate compared with group1(23.1% versus 45.5%, p=0.07). Overall hospital mortality was 11.5% in group1 versus 3.0% in group2. Prevalence of major complication was significantly lower in group 2 (46.2% versus 18.2%, p=0.02).Requirement of intraoperative blood transfusion (group 1;1,130.8±854.7 ml versus group 2;598.2±836.4 ml) and amount of blood loss in the 1st 12 hours post operation (group 1;628.3±474.6 ml versus group 2;447.8±253.2 ml) were significantly lower in group 2. By univariate analysis, duration of operation, duration of cardio-pulmonary bypass (CPB), blood transfusion, acute dissection were independent risk factors and CS use was negative risk factor for major events. Aortic root replacement with use of CS can be performed with a relatively low early mortality and morbidity. Because a complicated operation is increasing in recent years, use of CS graft may simplify a Bentall operation.

An 86-year-old man was admitted for abdominal pain. Dissected descending thoracic aortic aneurysm and infrarenal abdominal aortic aneurysm were observed under computed tomographic (CT) scan. Hematologic studies revealed low platelet count and an increase in fibrin degradation products (FDP), and disseminated intravascular coagulation( DIC) associated with dissecting aortic aneurysm was highly suspected. Platelet transfusion was performed and gabexate mesilate was administered, however, no improvement of DIC could be obtained. An increase in aortic diameter was observed under CT scan and surgery was performed. The infrarenal aneurysm was replaced with a bifurcated prosthetic graft under open repair. Simultaneously, an endovascular stent-graft was delivered from the left limb of the abdominal graft and implanted into the descending thoracic aorta. The postoperative recovery was uneventful but platelet count did not improve in this case.

Intraoperative autologous blood predonation is reported to be useful for the prevention of homologous blood transfusion in cardiac operations, especially in on-pump coronary artery bypass grafting (CABG). However, CABG is now performed more often off-pump than on-pump. We analyzed the major factors of homologous blood transfusion in 25 consecutive cases of valvular heart operation with intraoperative autologous blood predonation except those with preoperative autologous blood donation. Homologous blood was not transfused in 18 cases, but was in 7 cases only after cardiopulmonary bypass (CPB). The homologous transfusion was not correlated with body weight, CPB dilution or duration, or preoperative hematocrit level, but was found to correlate with age (r2=0.289, p=0.0413), bleeding output (r2=0.197, p=0.0485), and predonation blood volume (r2=0.436, p=0.0152). In conclusion, suitable intraoperative predonation may reduce the necessity for homologous blood transfusion in valvular heart operations.

The particle dispersibility of barium ferrite and iron oxide magnetic particles in carrageenan gels was investigated, and the influence of the dispersibility on the giant reduction in the dynamic modulus of the gels was discussed. The gels containing barium ferrite demonstrated giant reductions in the storage Young's modulus on the order of 10 (5) Pa due to magnetization; however, small reductions in the storage modulus of less than 10 (4) Pa were observed for the gels containing iron oxide. The storage modulus of gels with barium ferrite did not follow the Krieger-Dougherty equation above volume fractions of 0.06, indicating the heterogeneous dispersion of the magnetic particles; however, the modulus of the gels with iron oxide satisfied the equation at all volume fractions, suggesting the random dispersion of the particles. It was noted that the gels with barium ferrite demonstrated enhanced nonlinear viscoelasticity and a large value of the loss tangent, while the gels with iron oxide exhibited weak nonlinear viscoelasticity and a small value of the loss tangent. Magnetic measurements indicated high values of remanent magnetization for barium ferrite and low values for iron oxide. After magnetization at 1 T, the magnetic gels with barium ferrite became elongated parallel to the magnetic field and shrunk perpendicular to the field. In contrast, the magnetic gels with iron oxide did not undergo a marked deformation. These results strongly indicate that the giant reduction in the storage modulus requires both enhanced nonlinear viscoelasticity and magnetostriction which originate from the particle dispersibility. The relationship between the dispersibility of magnetic particles and the giant reduction in the storage modulus is discussed using rheological and morphological data.

Apoptosis is induced not only during morphogenesis and embryogenesis but also under various pathological conditions, especially related to oxidative stress. Apoptotic cells are phagocytized by neighboring cells while necrotic cells cause local and general reactions sometimes lethal to our bodies. Data have been accumulated to demonstrate that the switch of the cell death mode from apoptosis to necrosis does occur. However, detailed mechanisms involved in the switch mechanism remain unsolved although decreases in the intracellular level of ATP and a burst in the cellular level of reactive oxygen species (ROS) have been proposed. Recently, we have shown that the population of apoptotic cells reaches maximum in human osteosarcoma 143B cells treated for 6h with menadione (MEN) while necrotic cells become predominant at 9h of the treatment. In the present study we have attempted to clarify the role of cellular ATP in the switch mechanism using rho(0) cells derived from human osteosarcoma rho+ cells. Results are summarized as follows: (1) Apoptotic and necrotic changes in rho(0) cells are much faster than rho+ cells after the treatment with MEN. (2) Cellular level of ATP in rho(0) cells remains essentially in the same level before and after the MEN-treatment while intracellular levels of superoxide continuously increase after the MEN-treatment. (3) rho+ cells treated with MEN in the presence of antimycin A plus oligomycin show similar changes to those of MEN-treated rho(0) cells. (4) MEN-induced increases in the cellular level of superoxide are distinctly suppressed by inhibitors of NADPH oxidase. These results suggest that the intracellular level of superoxide may be a key factor directly related to the switch mechanism from apoptosis to necrosis, and that decreases in cellular level of ATP accelerate both apoptotic and necrotic changes of the cells.

Background: Partial liquid ventilation (PLV) with perfluorochemical (PFC) has been advocated as a new therapy for acute respiratory distress syndrome in both clinical and animal studies, meconium aspiration syndrome, and RDS. PFC is referred to as liquid PEEP because it gets distributed to the most gravity-dependent regions of the lung due to its density. High-frequency oscillation (HFO) has been shown to prevent both acute and chronic lung injury in the management of very low birth weight infants with RDS, with gentle ventilation approach. Specifically, HFO with aggressive and adequate lung volume recruitment has been shown to reduce the incidence of chronic lung disease in very low birth weight infants. We hypothesized that PLV along with HFO might be effective in ARDS in an adult rabbit model., Objectives: To examine the efficiency of low-dose PLV with with HFO on pulmonary gas exchange and lung compliance in a surfactant-depleted rabbit model., Methods: After induction of severe lung injury by repeated saline lung lavage, 19 adult white Japanese rabbits were randomized into two groups that received PLV with HFO (n=9) or HFO gas ventilation (n=10). Physiological and blood gas data were compared between the two groups by analysis of variance., Results: The HFO-PLV group showed improved total lung compliance with maintenance of significantly lower mean airway pressure as compared with the HFO-GAS group so as to keep SpO2>90%., Conclusions: The addition of a low dose of PFC with HFO was effective in achieving adequate oxygenation, with a reduction in further lung injury in neonates., (Copyright (c) 2006 S. Karger AG, Basel.)

Thymocytes exposed to the pro-oxidant tert-butyl-hydroperoxide (ButOOH) display a number of dramatic changes in morphology similar to those observed in the case of dexamethasone-treated cells. Both reagents induce nuclear chromatin peripheral aggregation below the nuclear membrane. Some nuclei themselves break up producing two or more fragments. ButOOH-treated cells are morphologically characterised by cell shrinkage, extensive surface blebbing and, finally, fragmentation into membrane-bound apoptotic bodies composed of cytoplasm and tightly packed with or without nuclear fragments. An increased level of lipid hydroxyperoxides was detected after exposure of thymocytes to ButOOH. Both oxidative stress markers and morphological damage to cells were prevented by the antioxidant 4-OH-TEMPO.

Time-dependent changes in the cell death mode from apoptosis to necrosis were studied in cultured 143B cells treated with menadione, an anti-cancerous drug, excluding a possible involvement of "secondary necrosis." The population of apoptotic cells judged by FITC-Annexin V and propidium iodide (PI) double staining reached its maximum at 6 hours after 100 microM menadione treatment followed by an abrupt decrease thereafter, while that of necrotic cells continuously increased reaching 90% at 24 hours. Electron microscopically, cells attached to the culture dish at 6 hours after the treatment consisted of two different types of cells: cells with typical apoptotic features occupying the major population and those with condensed nuclei and swollen cytoplasm. Cells attached to the culture dish at 8 hours after the treatment consisted exclusively of those with condensed nuclei and swollen cytoplasm. Mitochondria in these cells showed various structural changes: those swollen to various degrees with deposition of flocculent densities, or those with highly condensed matrix. Distinct decreases both in intracellular levels of ATP and caspase-3-like activities and remarkable elevations of intracellular levels of superoxide, which were partly suppressed by NAD(P)H oxidase inhibitors, occurred at 6 hours after the treatment. These results may suggest that distinct increases of the intracellular level of superoxide derived from plasma membrane NAD(P)H oxidase besides that from mitochondria have triggered the transition of cell death mode from apoptosis to necrosis. Transition of highly condensed mitochondria to extremely swollen ones may reflect necrotic processes in menadione-treated cells. The present study strongly suggests that time-dependent study is essential using the electron microscopic technique to analyze detailed processes in the changes of the cell death mode., (Copyright 2004 Wiley-Liss, Inc.)

The effects of inhibitors of plasma membrane NADPH oxidase on menadione-induced cell injury processes were studied using human osteosarcoma 143B cells. The intracellular level of superoxide in the cells treated with menadione for 6 h reached a maximum followed by an abrupt decrease. The population of apoptotic cells detected by Annexin V and propidium iodide double staining also reached its maximum at 6 h of menadione-treatment while that of necrotic cells increased continuously reaching 90% of the total population at 9 h of the treatment. Pretreatment of the cells with inhibitors of NADPH oxidase, including diphenyliodonium chloride, apocynin, N-vanillylnonanamide and staurosporine was effective in lowering the menadione-induced elevations of superoxide, and also in the suppression of the switch of the cell death mode from apoptosis to necrosis in menadione-treated cells except for the case of staurosporine. These results strongly suggest that superoxide generated by NADPH oxidase, besides that generated by the mitochondria, may contribute to the remarkable increase in the intracellular level of superoxide in the cells treated with menadione for 6 h resulting in the switch from apoptosis to necrosis, although a direct evidence of the presence of active and inactive forms of NADPH oxidase in control and menadione-treated 143B cells is lacking at present.

Characterization of free radical-induced cell injury processes of placenta cells is of vital importance for clinical medicine for the maintenance of intrauterine fetal life. The present study has analyzed cell injury processes in cells of the choriocarcinoma cell line JAR treated with menadione, an anticancer drug, and H(2)O(2) in comparison to osteosarcoma 143B cells using electron microscopic and flow cytometric techniques. Flow cytometry on JAR cells exposed to 100 muM menadione and double-stained with Annexin V and propidium iodide (PI) detected apoptotic cells reaching the maximum after 4 h of incubation with a rapid decrease thereafter. Viable cells became decreased to 46% of the control after 2 h of incubation, reaching 5% after 4 h. Cells stainable with both Annexin V and PI began to increase distinctly after 2 h of incubation, reaching 55% after 4 h. Electron microscopy showed that cells stainable with both dyes specified above had condensed nuclei and swollen cytoplasm, suggesting that they were undergoing a switch of the cell death mode from apoptosis to necrosis. On the other hand, 90% of 143B cells remained intact after 4 h of menadione treatment although the intracellular levels of superoxide were always higher than those of JAR cells treated with the drug. In contrast, JAR cells were more resistant than 143B cells to H(2)O(2)-induced cytotoxicity. These results may suggest that cytotoxicity of menadione cannot be explained simply by oxygen free radicals generated from the drug. The resistance of JAR cells to oxygen free radical-induced cytotoxicity may be advantageous for intrauterine fetal life.

In the present study we have shown that quinolinic aromatic aminoxyls are very efficient in protecting lipids of endoplasmic reticulum membranes against hydroperoxide-induced oxidation. The efficacy of these aminoxyls as protectors of lipids was much higher than the water-soluble 4-OH-TEMPO. We have also shown that QAL causes distinct changes of the morphology of mitochondria: from filamentous to granular enlarged structure via the folding of the former. QAL induces also perinuclear clustering of mitochondria. C-QAL as well as 4-OH-TEMPO treated cells revealed filamentous and scattered pattern of mitochondria. Antioxidant activity of QAL as well as morphological changes of mitochondrial raise the possibility that this drug can affect cell physiology via changes of mitochondrial function.

We have demonstrated for the first time that the steroid metabolite, 2-methoxyestradiol (2-ME) is a powerful growth inhibitor of human osteosarcoma 143 B cell line by pleiotropic mechanisms involving cell cycle arrest at two different points and apoptosis. The ability of 2-ME to inhibit cell cycle at the respective points has been found concentration dependent. 1 microM 2-ME inhibited cell cycle at G1 phase while 10 microM 2-ME caused G2/M cell cycle arrest. As a natural estrogen metabolite 2-ME is expected to perturb the stability of microtubules (MT) in vivo analogously to Taxol--the MT binding anticancer agent. Contrary to 2-ME, Taxol induced accumulation of osteosarcoma cells in G2/M phase of cell cycle only. The presented data strongly suggest two different mechanisms of cytotoxic action of 2-ME at the level of a single cell.

In the present study we examined the effects of menadione, a redox cycling agent, on structural changes of human osteosarcoma line 143B cells. It has been previously reported that menadione can cause necrotic or apoptotic cell death in a concentration- depending manner. In our experimental model, cells were treated with 100 microM menadione for 24 hours. Using electron microscopy technique cells carrying three kinds of morphological changes were detected: necrotic cells, apoptotic cells and those demonstrating a co-existence of apoptotic and necrotic features in one single cell.