Dynamic changes in parameters of redox balance after mild heat stress in aged laying hens (Gallus gallus domesticus)

In order to evaluate the metabolic responses of laying hens induced by high temperature at later laying stage, nine 60-wk-old laying hens (Gallus gallus domesticus) were employed in the present study. The hens were exposed to 32 degrees C for 21 d and blood samples were obtained before and at 1, 7, 14 and 21 d of heat exposure. The reactive oxygen species (ROS) formed in blood during heat exposure were estimated by the ex vivo spin-trapping method. Body temperature and plasma concentrations of glucose, urate, creatine kinase (CK), triiodothyronine (T(3)), thyroxine (T(4)), corticosterone (CORT), thiobarbituric acid reacting substances (TBARS), ferric/reducing antioxidant power (FRAP) and superoxide dismutase (SOD) activity were measured. Plasma levels of glucose, CK and CORT were not significantly influenced by heat exposure at any time point. The circulating concentrations of T(3) were decreased while plasma T(4) levels changed in the opposite way. The formation of ROS was significantly augmented by heat exposure in laying hens though the body temperature was not significantly altered. The enhanced enzymatic and non-enzymatic antioxidant systems acted in concert to alleviate the heat stress evoked oxidative damage.

Application of recombinant chum salmon cystatin to Alaska pollock (Theragra chalcogramma) surimi to prevent gel weakening

Recombinant chum salmon cystatin (RC) expressed in Saccharomyces cerevisiae was purified by His-select nickel affinity chromatography. The specific inhibitory activities of RC against papain and cathepsin L were 7.45 and 10.24 U/mg, respectively. RC was stable over pH 5.0 to 7.0 and at temperature below 65 degrees C. RC was used to prevent the gel weakening of Alaska pollock surimi. RC at 100 microg/g showed the highest inhibitory activity against the autolysis of surimi based on the analysis of TCA-soluble peptides. As the concentration of RC increased, both the breaking force and deformation of modori gel greatly increased (P < 0.05). The addition of RC resulted in less expressible drip, which coincided with the increase of whiteness. More myosin heavy chain (MHC) was retained as the addition of RC increased. Therefore, RC could prevent the degradation of proteins in Alaska pollock surimi and was better than egg white (EW). Thus, RC could be applied to Alaska pollock surimi to prevent gel weakening and RC at 100 microg/g was the optimal concentration.

BCR-ABL oncogenic transformation of NIH 3T3 fibroblasts requires the IL-3 receptor

Oncogenic transformation of hematopoietic cells by the Bcr-Abl oncoprotein directly involves the activation Jak2 tyrosine kinase and the Stat5 transcription factor. Both proteins are normally linked to the interleukin (IL)-3/granulocyte-macrophage colony-stimulating factor receptors for growth and survival. Since fibroblastic cells are not targets of BCR-ABL-induced oncogenesis, we determined whether forced expression of the IL-3 receptor would allow oncogenic transformation of NIH 3T3 fibroblasts known to be resistant to transformation by BCR-ABL. NIH 3T3 cells transduced with the human IL-3 receptor alpha and beta chains were highly susceptible to oncogenic transformation by expression of BCR-ABL. Forced expression of both receptor chains but not either one alone allowed efficient foci formation of NIH 3T3 cells expressing BCR-ABL (triple positive cells), and these cells formed colonies in soft agar, whereas BCR-ABL+ NIH 3T3 cells lacking IL-3 receptor expression did not. Signaling studies indicate that the BCR-ABL/IL-3 receptor+ NIH 3T3 cells utilize the Gab2/PI-3 kinase pathway activated by Jak2, and the Stat5 pathway activated separately by Bcr-Abl, whereas BCR-ABL+ NIH 3T3 cells lacking the IL-3 receptor do not utilize the Jak2 pathway, but still maintain activation of Stat5. The Bcr-Abl kinase inhibitor imatinib mesylate (1 microM) and two Jak2 kinase inhibitors strongly inhibited agar colony formation and the activation of Gab2 caused by Jak2. All of these findings indicate that Bcr-Abl oncoprotein requires the IL-3 receptor/Jak2/Stat5 pathways for oncogenic transformation of NIH 3T3 fibroblasts.

Small-molecule Bcl-2 inhibitors sensitise tumour cells to immune-mediated destruction

The cytotoxic effects of anticancer immune cells are mediated by perforin/granzyme-B, Fas ligand and tumour necrosis factor-related apoptosis-inducing ligand (TRAIL), and therefore depend on intact apoptotic responses in target tumour cells. As killing by all three of these mechanisms is blocked by the frequently overexpressed antiapoptotic oncoprotein Bcl-2, we hypothesised that coexposure to a Bcl-2 inhibitor might enhance anticancer immune responses. We evaluated this in U937 lymphoma cells, and A02 melanoma cells, which both show strong Bcl-2 expression. Vα24⁺ Vβ11⁺ natural killer T (NKT) cells expanded from peripheral blood of normal donors (n=3) were coincubated with PKH26-labelled U937 cells, and cytotoxicity was determined by flow cytometry after annexin-V-FITC and 7-AAD staining. In all cases, addition of the HA14-1 small-molecule Bcl-2 inhibitor to the cocultures significantly increased apoptosis in the target U937 cells. Using a similar assay, killing of A02 cells by the cytotoxic T-lymphocyte clone 1H3 was shown to be amplified by coexposure to the potent small-molecule Bcl-2 inhibitor ABT-737. Experiments with immune effectors preincubated with concanamycin-A suggested that sensitisation to perforin/granzyme-B may underlie enhanced target-cell killing observed in the presence of Bcl-2 inhibitors. We conclude that immune destruction of malignant cells can be amplified by molecular interventions that overcome Bcl-2-mediated resistance to apoptosis.

Androgen-dependent regulation of medium and long chain fatty acids uptake in prostate cancer

BACKGROUND

Epidemiological and experimental studies suggest that both fatty acids and androgens have a role in the development and progression of prostate cancer (PC). Plasma membrane fatty acid binding protein (FABP(pm)) is a transporter of medium and long chain fatty acids (MCFA and LCFA) across the plasma membrane, and is identical to the mitochondrial protein aspartate aminotransferase (mAAT) that is regulated by testosterone only in prostate epithelial cells, a site where PC initially develops. We therefore hypothesized that FABP(pm) is also regulated by androgens.

METHODS

We examined the effect of a synthetic androgen, R1881, and that of androgen receptor (AR) blocker, bicalutamide, on the expression of FABP(pm) and mAAT and on the uptake of fatty acids in the androgen-sensitive LNCaP, androgen responsive 22rv1 and androgen-independent CL1 human PC cells. This was done using immunofluorescence and confocal microscopy, Western blot, flow cytometry, and (3)H-oleate uptake studies.

RESULTS

Androgen supplementation increased the cellular and surface expression of FABP(pm) and mAAT and increased the uptake of fluorescently labeled MCFA and LCFA and that of (3)H-oleate only in PC cells that express the AR. Bicalutamide inhibited this phenomenon.

CONCLUSIONS

The uptake of MCFA and LCFA into PC cells is androgen regulated as well as the expression of FABP(pm) and mAAT.

Evidence for JNK-dependent up-regulation of proteoglycan synthesis and for activation of JNK1 following cyclical mechanical stimulation in a human chondrocyte culture model

OBJECTIVE

To examine the expression of mitogen-activated protein kinases (MAPKs) in human chondrocytes, to investigate whether selective activation of MAPKs is involved in up-regulation of proteoglycan (PG) synthesis following cyclical mechanical stimulation (MS), and to examine whether MS is associated with integrin-dependent or independent activation of MAPKs.

METHODS

The C-28/I2 and C-20/A4 human chondrocyte cell lines were mechanically stimulated in monolayer cell culture. PG synthesis was assessed by [(35)S]-sulphate incorporation in the presence and absence of the p38 inhibitor SB203580, and the extracellular-regulated kinase (ERK1/2) inhibitor PD98059. Kinase expression and activation were assessed by Western blotting using phosphorylation status-dependent and independent antibodies, and by kinase assays. The Jun N-terminal kinase (JNK) inhibitor SP600125 and the anti-beta(1) integrin (CD29) function-blocking antibody were used to assess JNK activation and integrin dependence, respectively.

RESULTS

Increased PG synthesis following 3 h of cyclic MS was abolished by pretreatment with 10 microM SB203580, but was not affected by 50 microM PD98059. The kinases p38, ERK1/ERK2 and JNKs were expressed in both stimulated and unstimulated cells. Phosphorylated p38 was detected at various time points following 0.5, 1, 2 and 3 h MS in C-28/I2, but not detected in C-20/A4 cell lines. Phosphorylation of ERK1 and ERK2 was not significantly affected by MS. Phosphorylation of the 54 and 46 kDa JNKs increased following 0.5, 1, 2 and 3 h of MS, and following CO(2) deprivation. MS-induced JNK phosphorylation was inhibited by SB203580 at concentrations > or =5 microM and activation of JNK1 following MS was blocked by SP600125 and partially inhibited by anti-CD29.

CONCLUSIONS

The data suggest JNK, rather than p38 or ERK dependent increases in PG synthesis, and selective, partially integrin-dependent, activation of JNK kinases in human chondrocyte cell lines following cyclical MS. JNK activation is also very sensitive to changes in CO(2)/pH in this chondrocyte culture model.

Spectral power distribution and quantum yields of Sm3+-doped heavy metal tellurite glass under the pumping of blue lighting emitting diode

Quantum yields for multichannel transition emissions have been determined in Sm3+-doped heavy metal tellurite glass under the pumping of blue lighting emitting diode for the first time. To achieve this goal, the necessary fluorescence spectra were measured and calibrated in an integrating sphere, which was connected to a CCD detector with a 400 microm-core optical fiber. The spectral power distribution of the sample under the blue LED pumping was derived from the measured spectra firstly, and then the quantum yields for the visible emissions of Sm3+ were calculated based on the distribution and the total quantum yields in visible region is 7.55%. For accurate measurements, integrating sphere method is proved to be a reliable and reproducible way to characterize luminescence and laser materials.

Uptake of polycyclic aromatic hydrocarbons by maize plants

Roots and above-ground parts (tops) of maize plants, comprising cuticles, leaves and stems, have been exposed separately to polycyclic aromatic hydrocarbons (PAHs) by means of air-tight bicameral exposure devices. Maize roots and tops of plants directly accumulate PAHs from aqueous solutions and from air in proportion to exposure levels. Root and leaf concentration factors (log RCF and log LCF) are log-linear functions of log-based octanol-water partition coefficient (log Kow) and log-based octanol-air partition coefficient (log Koa). The PAHs' concentrations among cuticles, leaves and stems display good correlations with each other. PAH concentrations in each part of the plant tested correlated positively with atmospheric PAHs' concentrations. Comparisons between PAHs' concentrations of root epidermis and root tissue showed similar correlations. Bulk concentrations of contaminants in various plant tissues differed greatly, but these differences disappeared after normalization to lipid contents suggesting lipid-based partitioning of PAHs among maize tissues.

Smokeless tobacco brand switching: a means to reduce toxicant exposure?

The purpose of this study was to examine the effects of smokeless tobacco (ST) brand switching on biomarkers of ST exposure and on ST use. Subjects seeking treatment to reduce their use were randomized to ST brand switching with controlled ST topography, brand switching with ad libitum ST use, or a waitlist control with subsequent randomization to one of these two conditions. The waitlist control group was included to assess whether changes were a consequence of time effect. During the intervention, Copenhagen or Kodiak ST users were asked to switch to products that were sequentially lower in nicotine content: Skoal Long Cut Straight or Wintergreen for 4 weeks and then Skoal Bandits for the subsequent 4 weeks. Measures were obtained during the course of treatment and at 12-week follow-up. Significant reductions in total urinary cotinine and 4-(methylnitrosamino)-L-(3-pyridyl)-L-butanol (NNAL) plus its glucuronides (total NNAL) were observed with no significant differences between the controlled topography and ad libitum conditions. Significant reductions were also observed in the amount and duration of dips with a significant intervention effect for durational measures. At 12 weeks, the 7-day biochemically-verified tobacco abstinent rate was 26% in the ad libitum group. ST brand switching may be a feasible alternative intervention for ST users interested in quitting but unwilling to stop ST use completely.

Effects of Diet and Stress Mimicked by Corticosterone Administration on Early Postmortem Muscle Metabolism of Broiler Chickens

Three experiments were conducted to evaluate the effects of preslaughter physiological states mimicked by long- or short-term administration of corticosterone (CORT) and dietary energy sources on muscle glycogen contents and meat quality of broiler chickens. In experiment 1, the broilers were fed a high lipid diet (LD) or a normal diet (ND) that differed in carbohydrate (3.8%) and lipid (2.5%) contents from 21 d of age. From 28 d of age onwards, 50% of the chickens in each dietary treatment were subjected to CORT treatment (30 mg/kg of diet). At 7 and 11 d after CORT supplementation, musculus pectoralis major was sampled before and immediately after slaughter and analyzed for glycogen, pH, and R-value. In experiment 2, broilers, fed with the LD or ND diet from 21 d of age were subjected to 1 single s.c. injection of CORT (4 mg/kg of BW) for 3 h to mimicked acute stress at 46 d of age. In experiment 3, broiler chickens were supplied with water supplemented with glucose (30 g/L) for 1 wk before slaughter and were then subjected to the same CORT treatment as experiment 2. Blood and muscle samples were respectively obtained before and immediately after slaughter and analyzed for plasma glucose, urate and lactic acid, and muscle variables. Plasma concentrations of glucose and urate were significantly increased by acute CORT administration, whereas the lactic acid was not changed. Neither dietary energy source nor water glucose supplementation had any influence on the plasma variables. Dietary energy source or water glucose supplementation could not alter glycogen stores in musculus pectoralis major. Breast muscle glycogen stores were increased by stress mimicked by long-term CORT administration rather than by acute treatment. Preslaughter stress reactions had no relation to the depletion of breast muscle glycogen during the initial postmortem period. The initial breast muscle pH was significantly decreased by long-term CORT administration. The result suggests that short-term upregulation of circulating CORT is not involved in the elevated drip loss induced by preslaughter stress.

Factors related to post-liver transplantation acute renal failure

Acute renal failure (ARF) after liver transplantation (OLT) is a common complication with severe impact on early and late prognosis of recipients. Factors predicting its incidence have not been fully identified due to the lack of a universal standard as well as the variance of data between transplant centers. To identify factors related to post-OLT ARF, we retrospectively collected materials on 89 patients, who underwent OLT from 1999 to 2001 in our center. Factors associated with post-OLT ARF were identified using univariate logistic regression. Significant factors were then entered into a multivariate logistic regression to identify factors independently associated with post-OLT ARF. Upon univariate analysis, intraoperative volume of blood transfusion (P = .041) and duration of operation (P = .005) were significant. ARF was associated with a poor prognosis (P < .001). Only duration of operation (P = .026) was an independent factor predicting the development of ARF. In conclusion, intraoperative volume of blood transfusion and duration of operation were factors contributing to post-OLT ARF in which the duration of the operation was an independent risk factor. The incidence of post-OLT ARF greatly increased recipient mortality in the early postoperative period.

A fiber-optic powered wireless sensor module made on elastomeric substrate for wearable sensors

We demonstrate an integrated sensor module that combines a photonic nano-porous sensor and a bias-free optical powered RF transducer. The sensor signal is encoded in the RF frequency ready for transmission. The entire sensor module does not include battery and is constructed with the flexible and biocompatible elastomeric polymer, PDMS. This technology holds promise for wearable sensors.

Identification of Lenke spine deformity classification by simplified 3D spine model

The 3D Bezier Curve is used to model the simplified 3D human spine for analyzing and classifying the scoliotic deformity. This 3D spine model is based on two orthogonal spinal radiographic images taken from coronal and sagittal planes. Superimposed on these two images, the 3D Bezier curves are fitted interactively onto the center of the spine from coronal and sagittal images. After the 3D Bezier Curve fitting, a series of simplified 3D vertebrae are implemented onto the 3D Bezier Curve proportional in size to its axis. The Lenke Classification system is applied to this 3D spine model. In order to identify the Lenke Classification for each individual spine model, the left side bending and right side bending images are added. Bending the 3D spine model interactively to the left and right determines the stiffness of the spinal deformity and whether the curves are structural. Thus the Lenke Classification could be determined.

Altered development and protein metabolism in skeletal muscles of broiler chickens (Gallus gallus domesticus) by corticosterone

Two trials were conducted to investigate the effect of corticosterone (CORT) on protein metabolism and the amino acid composition in muscle tissues of broiler chickens (Gallus gallus domesticus). In Trial 1, two groups of 30 broiler chickens were subjected to control or CORT treatment (30 mg/kg diet) from 28 to 39 days of age. In Trial 2, three groups of chickens of 28 days of age were randomly subjected to one of the following treatments for 7 days: CORT (30 mg/kg diet), pair-fed (maintaining the same feed intake as CORT treatment) and control treatments. The body mass gain and feed efficiency was significantly decreased by CORT treatment, while the food intake was decreased. The breast and thigh masses (% body mass) were significantly suppressed by CORT treatment, while the abdominal fat and liver masses (%) were obviously increased. The plasma levels of glucose, urate and total amino acid were significantly elevated by CORT treatment. The capacity for protein synthesis, estimated by RNA:protein ratio, were significantly suppressed by CORT in M. pectoralis major and M. biceps femoris. The 3-methylhistidine concentrations were significantly increased in both M. pectoralis major and M. biceps femoris of CORT chickens, compared to control but not the pair-fed chickens. The amino acid composition of M. pectoralis major and M. biceps femoris was not significantly affected by CORT treatment. In conclusion, the arrested growth in skeletal muscles induced by CORT administration has tissue specificity. The CORT treatment retards the growth of skeletal muscle by suppressed protein synthesis and augmented protein catabolism.