Cytokeratin 7 and Copper Stains Facilitate Diagnosis of Small Duct Primary Sclerosing Cholangitis

Introduction/Objective

Classic primary sclerosing cholangitis (PSC) involves extrahepatic and/or intrahepatic biliary ducts with segmental biliary strictures and dilatations that often allow the diagnosis to be made via cholangiogram. Small duct PSC (sdPSC) is a rare subtype that presents similarly with a cholestatic pattern of injury, yet due to the small size of involved ducts, a cholangiogram is non-diagnostic and diagnosis is dependent on clinical suspicion and liver biopsy. The histopathological features of sdPSC are often subtle and may easily be overlooked. Diagnosis of this entity- though difficult- is important, as early recognition can facilitate the identification of associated disease processes and life-threatening complications.

Methods/Case Report

We encountered a 33-year-old female presenting with intermittent pruritis, episodes of jaundice, and persistently elevated alkaline phosphatase who was misdiagnosed with only fatty liver at an outside institution. Evaluation with MRCP showed no abnormalities within the biliary tract and a liver biopsy was performed to aid in the diagnosis. The H&E and trichrome findings of atrophic bile ducts and some peribiliary sclerosis were extremely subtle and may have been overlooked without clinical suspicion. Cytokeratin 7 (CK7) highlighted cholangiolar metaplasia in hepatocytes and the bile ductular reaction that occurs in cholestatic disease states. A Rhodamine copper stain showed periportal deposition suggestive of chronic biliary obstruction. Use of CK7 and copper stains supported the presence of chronic biliary injury and suboptimal bile flow, confirming the diagnosis of sdPSC.

Results (if a Case Study enter NA)

NA

Conclusion

Diagnosis of sdPSC has historically relied on H&E and trichrome stains. In this case, the findings on H&E and trichrome stains were non-diagnostic, while the use of CK7 and copper stains confirmed the diagnosis of sdPSC. We recommend using CK7 and copper stains to evaluate for sdPSC.

Optimization of cryopreservation protocols for cooled-transported stallion semen

Freezing cooled-transported semen allows veterinarians and breeders to collect and process the semen of stallions on farm, and then ship the semen to a semen freezing center. There, however, is a lack of standardization of shipping and freezing protocols. The objectives were to optimize and simplify protocols to freeze cooled-shipped semen. In Experiment 1, cooled-transported semen was centrifuged at room temperature or 5 °C before freezing. Sperm variables (motility, membrane integrity, acrosome integrity, membrane fluidity) were evaluated before and after freezing. Centrifugation temperature had no effect on post-thaw semen quality. In Experiment 2, cooled-transported semen was centrifuged at room temperature and cryopreserved in three semen freezing extenders. With use of the improved modified French formula, there was less post-thaw total and progressive motility compared with use of Botucrio or the improved lactose-EDTA formula (P<0.0001). Semen cryopreserved in the improved modified French formula also had a lesser percentage of sperm with intact membranes compared with lactose-EDTA, and a greater percentage of sperm with capacitation-like changes compared with Botucrio (P<0.0001). In Experiment 3, semen diluted in each extender was frozen conventionally or placed directly in a -80 °C ultra-freezer. Freezing in the ultra-freezer resulted in a lesser post-thaw sperm motility, but not membrane and acrosome integrity and capacitation-like changes. In conclusion, centrifugation and addition of freezing extender to cooled transported semen can be performed at room temperature or 5 °C. The Botucrio and lactose-EDTA formula are recommended for conventional cryopreservation of cooled-transported stallion semen as compared with the modified French formula.

Comparison of cushioned centrifugation and SpermFilter filtration on longevity and morphology of cooled-stored equine semen

This study compares two methods for seminal plasma removal by evaluating sperm recovery rates, and motility and morphology of cooled-stored semen. Ejaculates were divided into three groups: control, filtration and cushioned centrifugation. Semen was extended to 25 million sperm/ml using a skim-milk-based extender and stored at 5°C for all groups. Sperm motility (total motility (%TM) and progressive motility (%PM)) was determined at 0, 24, 48 and 72 hours by a computer-assisted sperm analyser. Sperm morphology was assessed using differential interference microscopy. Overall, %TM of the centrifugation group was significantly higher than the filter group, but not significantly different than the control. No significant difference in %TM or %PM was detected for the control group and filter. Cushioned centrifugation was a superior method to obtain progressively motile sperm compared with control (P=0.03) and filter groups (P<0.001). No significant difference was found for the per cent of normal sperm cells and detached heads between the groups. This study demonstrated that cushioned centrifugation was a superior method to remove seminal plasma while preserving %TM and enhancing %PM for stallions under cooled storage over three days. However, as the differences appear to be negligible, the SpermFilter may represent an alternative for farms lacking a centrifuge.

α-TEA cooperates with MEK or mTOR inhibitors to induce apoptosis via targeting IRS/PI3K pathways

Background:

α-Tocopherol ether-linked acetic acid (α-TEA) is a promising agent for cancer prevention/therapy based on its antitumour actions in a variety of cancers.

Methods:

Human breast cancer cells, MCF-7 and HCC-1954, were used to study the effect of α-TEA using Annexin V/PI staining, western blot analyses, and siRNA knockdown techniques.

Results:

α-Tocopherol ether-linked acetic acid suppressed constitutively active basal levels of pAKT, pERK, pmTOR, and their downstream targets, as well as induced both cell types to undergo apoptosis. Phosphoinositide 3-kinase (PI3K) inhibitor wortmannin suppressed pAKT, pERK, pmTOR, and their downstream targets, indicating PI3K to be a common upstream mediator. In addition, α-TEA induced increased levels of pIRS-1 (Ser-307), a phosphorylation site correlated with insulin receptor substrate-1 (IRS-1) inactivation, and decreased levels of total IRS-1. Small interfering RNA (siRNA) knockdown of JNK blocked the impact of α-TEA on pIRS-1 and total IRS-1 and impeded its ability to downregulate the phosphorylated status of AKT, ERK, and mTOR. Combinations of α-TEA+MEK or mTOR inhibitor acted cooperatively to induce apoptosis and reduce basal levels of pERK and pmTOR. Importantly, inhibition of MEK and mTOR resulted in increased levels of pAKT and IRS-1, and α-TEA blocked them.

Conclusions:

Downregulation of IRS-1/PI3K pathways via JNK are critical for α-TEA and α-TEA+MEK or mTOR inhibitor-induced apoptosis in human MCF-7 and HCC-1954 breast cancer cells.

RRR-alpha-tocopheryl succinate induces MDA-MB-435 and MCF-7 human breast cancer cells to undergo differentiation

RRR-alpha-Tocopheryl succinate (vitamin E succinate, VES) is a potent antitumor agent, inducing DNA synthesis arrest, differentiation, and apoptosis. Because little is known about VES-induced differentiation, studies reported here characterize VES effects on the differentiation status of human breast cancer cell lines and investigate possible molecular mechanisms involved. VES-induced differentiation of human MCF-7 and MDA-MB-435 breast cancer cells was characterized by morphological changes, induction of lipid droplets, induction of beta-casein mRNA expression, and down-regulation of Her2/neu protein. In contrast, VES treatment of normal human mammary epithelial cells, MCF-10A cells, and T-47D cells did not induce differentiation. Studies addressing mechanisms showed that neither antibody neutralization of the transforming growth factor-beta signaling pathway nor expression of a dominant-negative mutant of c-Jun N-terminal kinase blocked the ability of VES to induce differentiation; however, treatment of cells with PD 98059, a chemical inhibitor of mitogen-activated protein kinase kinase (MEK1/2), blocked the ability of VES to induce differentiation.

Activation of extracellular signal-regulated kinase and c-Jun-NH(2)-terminal kinase but not p38 mitogen-activated protein kinases is required for RRR-alpha-tocopheryl succinate-induced apoptosis of human breast cancer cells

RRR-alpha-tocopherol succinate (vitamin E succinate, VES) is a potent, selective apoptotic agent for cancer cells but not normal cells. VES has been shown to inhibit the growth of a wide variety of tumor cells in cell culture and animal models. Studies addressing mechanisms of action of VES-induced apoptosis have identified transforming growth factor-beta, Fas/CD95-APO-1, and mitogen-activated protein kinase (MAPK) signaling pathway involvement. Here we show that MAPKs, the extracellular signal-regulated kinases (ERK), and the stress-activated protein kinases, c-Jun NH2-terminal kinases (JNK), but not p38, are critical mediators in VES-induced apoptosis of human breast cancer MDA-MB-435 cells. VES activates ERK1/2 and JNK both in level and duration of kinase activity. Expression of dominant negative mutants of ERK1, MAPK/ERK activator-1, or JNK1 but not p38 blocked phosphorylation of the substrate glutathione S-transferase-c-Jun and inhibited VES-induced apoptosis. Increased phosphorylation and transactivation activity of nuclear transcription factors c-Jun, ATF-2, and Elk-1 are observed after VES treatments; however, only c-Jun and ATF-2 appear to be involved in VES-induced apoptosis based on antisense blockage experiments. Collectively, these results imply a critical role for ERK1 and JNK1 but not p38 in VES-induced apoptosis of human MDA-MB-435 breast cancer cells.

Vitamin E succinate induces apoptosis in human prostate cancer cells: role for Fas in vitamin E succinate-triggered apoptosis

The apoptosis-triggering properties of vitamin E succinate (VES, RRR-alpha-tocopheryl succinate) for human LNCaP and PC-3 prostate carcinoma cells and normal PrEC human prostate epithelial cells were investigated. LNCaP and PC-3 cells were sensitive to VES-induced apoptosis, with 100% and 60% of cells undergoing apoptosis after three days of treatment with 10 micrograms of VES/ml, respectively. PrEC cells were resistant to VES-induced apoptosis. Treatment of prostate cells with agonistic anti-Fas antibody triggered apoptosis in approximately 50% of PC-3 cells within 48 hours, whereas LNCaP and PrEC cells were resistant. Prostate cells simultaneously treated with VES and agonistic anti-Fas antibodies revealed 1) no effect on PrEC cells, 2) an additive effect on Fas-sensitive PC-3 cells, and 3) a synergistic effect on LNCaP cells. VES treatment of LNCaP cells caused depletion of cytosolic 43-kDa Fas, enhanced membrane levels of 43-kDa Fas, and induced Fas sensitivity. PC-3 cells expressed high levels of membrane 43-kDa Fas that were enhanced by VES treatments. Fas ligand expression by LNCaP cells was enhanced by VES treatments. In summary, VES triggers apoptosis in human prostate carcinoma cells but not normal prostate cells in vitro, and VES modulates Fas signaling.

Stable expression of a new chimeric fluorescent reporter in the human malaria parasite Plasmodium falciparum

Stable transfection of a new, chimeric reporter in the human malaria parasite Plasmodium falciparum confers green fluorescence and methotrexate resistance that can be quantitated by Western blotting and flow cytometry. This provides a sensitive, live reporter for exploitation of genomic and high-throughput assays for the identification of new pathogenic determinants.

N-(4-hydroxyphenyl)retinamide activation of transforming growth factor-beta and induction of apoptosis in human breast cancer cells

N-(4 hydroxyphenyl)retinamide (4-HPR), a synthetic derivative of all-trans-retinoic acid, induces DNA synthesis arrest and apoptosis in human breast cancer cells in a dose- and time-dependent manner. MDA-MB-435 cells treated with 3 microM 4-HPR exhibited 58% and 75% DNA synthesis arrest after 1 and 2 days of treatment and 31%, 39%, 48%, and 56% apoptosis after 3, 4, 5, and 6 days of treatment, respectively. Conditioned media from 4-HPR-treated MDA-MB-435 cells contained 63 and 57 pg of active transforming growth factor-beta (TGF-beta) per 10(6) cells after 1 and 2 days of treatment, whereas conditioned media from control cells contained only 9 pg/10(6) cells. TGF-beta involvement in 4-HPR-induced apoptosis, but not DNA synthesis arrest, in MDA-MB-435 cells was demonstrated by 1) blockage of 4-HPR-induced apoptosis by 66-75% after treatment of cells with neutralizing antibodies to TGF-beta s, 2) blockage of 4-HPR-induced apoptosis by 64-67% after transient transfection of cells with antisense oligomers to TGF-beta 1 or TGF-beta type II receptor, 3) blockage of 4-HPR-induced apoptosis by approximately 50% after inhibition of latent TGF-beta activation, and 4) demonstration that human breast cancer cells (T47D) defective in TGF-beta signaling were refractive to 4-HPR-induced apoptosis. These data indicate that 4-HPR is a potent activator of TGF-beta and that TGF-beta participates in 4-HPR-induced apoptosis of human breast cancer cells.

Induction of apoptosis in human breast cancer cells by tocopherols and tocotrienols

The apoptosis-inducing properties of RRR-alpha-, beta-, gamma-, and delta-tocopherols, alpha-, gamma-, and delta-tocotrienols, RRR-alpha-tocopheryl acetate (vitamin E acetate), and RRR-alpha-tocopheryl succinate (vitamin E succinate) were investigated in estrogen-responsive MCF7 and estrogen-nonresponsive MDA-MB-435 human breast cancer cell lines in culture. Apoptosis was characterized by two criteria: 1) morphology of 4,6-diamidino-2-phenylindole-stained cells and oligonucleosomal DNA laddering. Vitamin E succinate, a known inducer of apoptosis in several cell lines, including human breast cancer cells, served as a positive control. The estrogen-responsive MCF7 cells were more susceptible than the estrogen-nonresponsive MDA-MB-435 cells, with concentrations for half-maximal response for tocotrienols (alpha, gamma, and delta) and RRR-delta-tocopherol of 14, 15, 7, and 97 micrograms/ml, respectively. The tocotrienols (alpha, gamma, and delta) and RRR-delta-tocopherol induced MDA-MB-435 cells to undergo apoptosis, with concentrations for half-maximal response of 176, 28, 13, and 145 micrograms/ml, respectively. With the exception of RRR-delta-tocopherol, the tocopherols (alpha, beta, and gamma) and the acetate derivative of RRR-alpha-tocopherol (RRR-alpha-tocopheryl acetate) were ineffective in induction of apoptosis in both cell lines when tested within the range of their solubility, i.e., 10-200 micrograms/ml. In summary, these studies demonstrate that naturally occurring tocotrienols and RRR-delta-tocopherol are effective apoptotic inducers for human breast cancer cells.

Vitamin E succinate (VES) induces Fas sensitivity in human breast cancer cells: role for Mr 43,000 Fas in VES-triggered apoptosis

Fas (CD95/APO-1) is an important mediator of apoptosis. We show that Fas-resistant MCF-7, MDA-MB-231, and MDA-MB-435 human breast cancer cells become responsive to anti-Fas (CD95) agonistic antibody-triggered apoptosis after pretreatment or cotreatment with vitamin E succinate (VES; RRR-alpha-tocopheryl succinate). In contrast, no enhancement of anti-Fas agonistic antibody-triggered apoptosis was observed following VES pretreatment or cotreatment with Fas-sensitive primary cultures of human mammary epithelial cells, immortalized MCF-10A cells, or T47D human breast cancer cells. Although VES is itself a potent apoptotic triggering agent, the 6-h pretreatment procedure for Fas sensitization did not initiate VES-mediated apoptosis. The combination of VES plus anti-Fas in pretreatment protocols was synergistic, inducing 2.8-, 3.0-, and 6.3-fold enhanced apoptosis in Fas-resistant MCF-7, MDA-MB-231, and MDA-MB-435 cells, respectively. Likewise, cotreatment of Fas-resistant MCF-7, MDA-MB-231, and MDA-MB-435 cells with VES plus anti-Fas enhanced apoptosis 1.9-, 2.0-, and 2.6-fold, respectively. Functional knockout of Fas-mediated signaling with either Fas-neutralizing antibody (MCF-7-, MDA-MB-231-, and MDA-MB-435-treated cells) or Fas antisense oligomers (MDA-MB-435-treated cells only), reduced VES-triggered apoptosis by approximately 50%. Analyses of whole cell extracts from Fas-sensitive cells revealed high constitutive expression of Mr 43,000 Fas, whereas Fas-resistant cells expressed low levels that were confined to the cytosolic fraction. VES treatment of the Fas-resistant cells caused a depletion of cytosolic Mr 43,000 Fas with a concomitant increase in Mr 43,000 membrane Fas. These data show that VES can convert Fas-resistant human breast cancer cells to a Fas-sensitive phenotype, perhaps by translocation of cytosolic Mr 43,000 Fas to the membrane and show that VES-mediated apoptosis involves Mr 43,000 Fas signaling.

Absence of longitudinal changes in rheumatologic parameters after silicone breast implantation: a prospective 13-year study

There have been numerous questions regarding the association of polysiloxane with connective tissue disease and alteration of host immune response. C-reactive protein, rheumatoid factor, and anti-streptolysin-O titers were measured in 218 patients. These studies are routinely used in the diagnosis of autoimmune disease and mixed connective tissue disease. This prospective study has been in progress since 1985. The first patients were seen in July of 1985, and those individuals willing to participate were followed from 1985 to 1998. The implants included saline-filled elastomer shells and polysiloxane gel-filled elastomer shells. These groups were examined separately and in combination for changes between preoperative and postoperative states. In each instance, there was no statistical increase or decrease. Each patient underwent a physical examination and completed a questionnaire focusing on signs and symptoms of autoimmune and connective tissue diseases. The laboratory data and subjective clinical results demonstrated no significant differences between a nonimplanted group versus the saline group alone, the gel group alone, or the combined groups. The data failed to suggest any causal relationship between implants and autoimmune or connective tissue diseases over the study period of 13 years (since 1985).

RRR-alpha-tocopheryl succinate induction of prolonged activation of c-jun amino-terminal kinase and c-jun during induction of apoptosis in human MDA-MB-435 breast cancer cells

We have demonstrated that RRR-alpha-tocopheryl succinate (10 microg/mL vitamin E succinate (VES) treatment of estrogen receptor-negative MDA-MB-435 human breast cancer cells induces 9, 19, 51, and 72% apoptotic cells on days 1-4, respectively, after treatment, which involves transforming growth factor-beta signaling. Here, we show that VES-triggered apoptosis of MDA-MB-435 cells induced prolonged elevated expression of c-jun mRNA and protein (neither of which was caused by major increases in stability) and also induced enhanced activator protein-1 (AP-1) binding to the consensus DNA oligomer. Furthermore, VES treatments resulted in increased AP-1 transactivation activity, as measured with an AP-1 promoter/luciferase reporter construct and by the measurement of increased mRNA expression of the AP-1-dependent endogenous gene collagenase. Evidence of VES-induced involvement of the c-jun amino-terminal kinase in these AP-1-dependent events was suggested by data showing prolonged activity of this kinase, as measured by a kinase assay using glutathione S-transferase-c-jun as the substrate. The c-jun-dependent transcriptional activity was verified by cotransfection of a chimeric transcription factor having a galactose 4 DNA-binding domain coupled with the transactivation domain of c-jun plus the reporter plasmid 5X GAL4-luciferase. MDA-MB-435 cells infected with an adenovirus expression vector containing the TAM-67 sequence for dominant/negative-acting mutant c-jun or transiently transfected with c-jun antisense exhibited a 50-77% reduction in VES-mediated apoptosis as compared with control adenovirus-infected or control sense oligomer-transfected cells.

Family history of hypertension: a psychophysiological analysis

Family history of hypertension (positive and negative) and gender groups were compared on cardiovascular responses at rest, during stressors and during recovery. Two tasks were employed, mental arithmetic and an anger recall interview. Both levels and reactivity measures of blood pressure, heart rate, cardiac output and total peripheral resistance were included. In addition, participants filled out several questionnaires measuring state feelings during the task and recovery periods, trait anger/hostility and emotions. Both men and women with a positive family history of hypertension exhibited higher tonic levels of blood pressure and heart rate at rest, recovery and during both tasks. They also exhibited greater heart rate reactivity during the mental arithmetic task and greater blood pressure reactivity to both tasks when post-math recovery, but not initial rest, was used as a covariate. Positive family history individuals reported less trust and gregariousness, more depression and aggression, less awareness of somatic responses to the tasks and less effort to relax during the post-task rest periods. Finally, significant correlations were found between low anger expression how anger experience and high anger control and task SBP levels in positive family history individuals.

c-Jun involvement in vitamin E succinate induced apoptosis of reticuloendotheliosis virus transformed avian lymphoid cells

Previous studies have shown that treatment of avian reticuloendotheliosis virus-transformed RECC-UTC4-1 (C4-1) lymphoblastoid cells with 10 microg/ml (18.8 microM) of RRR-alpha-tocopheryl succinate (vitamin E succinate, VES) for 3 days induced approximately 50% of the cells to undergo apoptosis. Elevated and prolonged expression of c-jun mRNA and protein was temporally correlated with VES-induced cell death. Data presented in this paper show that the elevated and prolonged expression of c-jun message and protein are not accounted for by enhanced stability, and show the involvement of c-Jun in VES-induced apoptosis in this lymphoblastoid cell type. C4-1 cells infected with a virus carrying a dominant, negatively acting mutant form of c-Jun, supjun-1, exhibited: (i) 71% reduction in VES-induced apoptosis, (ii) a 2.0-2.5-fold decrease in wildtype, endogenous c-Jun expression, and (iii) a 2.4-2.6-fold reduction in AP-1 binding activity. Additionally, cells co-treated with VES plus RRR-alpha-tocopherol, exhibited a 70% reduction in apoptosis, a marked reduction in c-Jun expression and a 1.6-fold reduction in AP-1 binding activity. These studies suggest that c-Jun plays a crucial role in VES-induced apoptosis in C4-1 cells, and add to our understanding of mechanisms of action involved in VES-mediated tumor cell growth inhibition.

Involvement of activator protein-1 (AP-1) in induction of apoptosis by vitamin E succinate in human breast cancer cells

The purpose of this study was to document induction of apoptosis by vitamin E succinate (VES; RRR-alpha-tocopheryl succinate) in human breast cancer cells in culture and to characterize potential c-jun involvement. VES at 18.8 microM (10 micrograms/mL) induced DNA synthesis arrest, reduced total cell numbers, and induced apoptosis in estrogen receptor-positive and estrogen-responsive MCF-7 human breast cancer cells. VES at 10 micrograms/mL induced apoptosis in greater than 60% of cells within 3 d of treatment. Apoptosis was documented by detection of fragmented or condensed nuclei in 4',6-diamindino-2-phenylindole-stained cells, detection of terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeled DNA, and DNA laddering. Analyses of mRNA and protein levels of candidate molecules involved in apoptosis showed that MCF-7 cells treated with VES exhibited elevated and persistent expression of c-jun. MCF-7 cells stably transfected with a dominant-negative interfering mutant c-jun, TAM-67, and expressing high levels of mutant jun exhibited approximately 50% blockage of VES-mediated apoptosis. In addition to increased c-jun expression after VES treatment, VES-treated MCF-7 cells exhibited elevated activator protein-1 (AP-1) binding activity. Comparisons of AP-1 binding factors by super-shift analyses with jun-specific antibodies in cells sensitive to VES-induced apoptosis (empty-vector control 7-1 cells) and cells resistant to VES-induced apoptosis (TAM-67-containing TAM-9 cells) showed that the sensitive cells expressed c-jun and jun D and the resistant cells TAM-67 AP-1 binding proteins after VES treatment. These studies suggested that c-jun may be involved in the apoptotic process initiated by VES treatment of human MCF-7 breast cancer cells.

Evidence for role of transforming growth factor-beta in RRR-alpha-tocopheryl succinate-induced apoptosis of human MDA-MB-435 breast cancer cells

MDA-MB-435 human breast cancer cells treated with 10 micrograms/ml of RRR-alpha-tocopheryl succinate (vitamin E succinate, VES) for one, two, three, and four days exhibit 9%, 19%, 51%, and 73% apoptotic cells, respectively. Likewise, cells cultured for one, two, and three days with conditioned media (CM) obtained from MDA-MB-435 cells treated with VES exhibit 10%, 36%, and 74% apoptosis, respectively. A quantitative luciferase-based assay showed CM from VES-treated cells collected at 24 and 48 hours after treatment initiation to contain 75 and 32 pg of active transforming growth factor-beta (TGF-beta), respectively, per 10(6) cells. Although purified TGF-beta 1 is not an effective apoptotic agent for MDA-MD-435 cells, cotreatment of the cells for three days with suboptimal levels of VES (2.5 and 5 micrograms/ml) + 10 ng/ml of purified TGF-beta 1 enhanced apoptosis by 66% and 68%, respectively. Interference of the TGF-beta-signaling pathway by transient transfection of MDA-MB-435 cells with antisense oligomers to TGF-beta type II receptor (TGF-beta R-II) blocked VES-induced apoptosis. Likewise, addition of neutralizing antibodies to TGF-beta 1 or to all three mammalian isoforms of TGF-beta (TGF-beta 1, -beta 2, -beta 3) blocked VES- and CM-induced apoptosis. Furthermore, inhibitors of TGF-beta conversion from an inactive latent form to a biologically active form inhibited VES-induced apoptosis. In summary, the ability to reduce apoptosis by blocking TGF-beta or the TGF-beta receptor-signaling pathway with antisense oligomers or ligand-neutralizing antibodies or prevention of activation of TGF-beta indicates a role for TGF-beta signaling in VES-induced apoptosis.

RRR-alpha-tocopheryl succinate inhibits EL4 thymic lymphoma cell growth by inducing apoptosis and DNA synthesis arrest

RRR-alpha-tocopheryl succinate (vitamin E succinate, VES) treatment of murine EL4 T lymphoma cells induced the cells to undergo apoptosis. After 48 hours of VES treatment at 20 micrograms/ml, 95% of cells were apoptotic. Evidence for the induction of apoptosis by VES treatments is based on staining of DNA for detection of chromatin condensation/fragmentation, two-color flow-cytometric analyses of DNA content, and end-labeled DNA and electrophoretic analyses for detection of DNA ladder formation. VES-treated EL4 cells were blocked in the G1 cell cycle phase; however, apoptotic cells came from all cell cycle phases. Analyses of mRNA expression of genes involved in apoptosis revealed decreased c-myc and increased bcl-2, c-fos, and c-jun mRNAs within three to six hours after treatment. Western analyses showed increased c-Jun, c-Fos, and Bcl-2 protein levels. Electrophoretic mobility shift assays showed increased AP-1 binding at 6, 12, and 24 hours after treatment and decreased c-Myc binding after 12 and 24 hours of VES treatment. Treatments of EL4 cells with VES+RRR-alpha-to-copherol reduced apoptosis without effecting DNA synthesis arrest. Treatments of EL4 cells with VES+rac-6-hydroxyl-2, 5,7,8-tetramethyl-chroman-2-carboxylic acid, butylated hydroxytoluene, or butylated hydroxyanisole had no effect on apoptosis or DNA synthesis arrest caused by VES treatments. Analyses of bcl-2, c-myc, c-jun, and c-fos mRNA levels in cells receiving VES + RRR-alpha-tocopherol treatments showed no change from cells receiving VES treatments alone, implying that these changes are correlated with VES treatments but are not causal for apoptosis. However, treatments with VES + RRR-alpha-tocopherol decreased AP-1 binding to consensus DNA oligomer, suggesting AP-1 involvement in apoptosis induced by VES treatments.

RRR-alpha-tocopheryl succinate induces apoptosis in avian retrovirus-transformed lymphoid cells

The RRR-alpha-tocopheryl succinate form of vitamin E [vitamin E succinate (VES)] inhibits the proliferation of avian reticuloendotheliosis virus-transformed RECC-UTC4-1 (C4-1) lymphoblastoid cells in a dose-dependent manner, blocks the cells in the G2/M cell cycle phase, and induces the cells to undergo apoptosis. Apoptosis was documented by demonstrating changes that are characteristic of this type of cell death, including morphological analyses of chromatin condensation by 4',6-diamidine-2'-phenylindole dihydrochloride (DAPI) staining using scanning confocal and traditional fluorescent microscopy; flow cytometry analyses of propidium iodide-labeled DNA showing fragmented DNA as a pre-G1 peak; two-color flow cytometry analyses of intact cells labeled first by the TUNEL procedure (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick-end-labeled DNA stained with fluorescein isothiocyanate-labeled avidin) and then by propidium iodide demonstrating fragmented DNA; and electrophoresis of DNA showing a DNA ladder created by internucleosomal DNA fragmentation. The percentage of apoptotic cells was determined by DAPI staining and showed 11%, 27%, and 49% of cells to be apoptotic after treatment with 10 micrograms/ml VES for one, two, and three days, respectively. Analyses of mRNA levels of genes that have been implicated in the apoptotic process, namely, bcl-2, c-myc, and c-jun, revealed no change in bcl-2, decreases in c-myc mRNA levels after 36 hours of treatment, and increases in c-jun mRNA levels within four hours after treatment. Western immunoblotting analyses of protein levels for the transcription factors c-Myc and c-Jun showed normal levels of c-Myc at early time points and decreased levels at 24 and 48 hours after treatment. c-Jun increased as early as 6 hours after treatment and returned to lower (yet still elevated over control) levels by 48 hours. To determine possible functional consequences of increased c-Jun expression, gel electrophoretic mobility assays were conducted that showed increased AP-1 binding at 24 and 48 hours after treatment. These data show that VES induces apoptosis in reticuloendotheliosis virus-transformed lymphoid cells and suggest that decreases of c-Myc protein and increases of c-Jun protein and DNA binding capacity may be playing a role in VES-mediated events leading to apoptosis in this cell type.

Modulation of murine EL-4 thymic lymphoma cell proliferation and cytokine production by vitamin E succinate

RRR-alpha-tocopheryl succinate (VES) was studied for effects on murine EL-4 cell proliferation and production of interleukin-2 (IL-2) and transforming growth factor-beta (TGF-beta). VES was biphasic in its actions: 0.1 microgram/ml enhanced EL-4 cell proliferation, whereas 10-20 microgram/ml inhibited cellular proliferation. Cell-conditioned media (CM) from EL-4 cells treated with 0.2 ng/ml phorbol myristate acetate (PMA) + 0.1 microgram/ml VES contained increased amounts of IL-2, as determined by the murine cytotoxic T cell IL-2-dependent CTLL-2 bioassay. VES at 0.1 microgram/ml or 0.1 microgram/ml VES + 0.2 ng/ml PMA induced the expression of IL-2 mRNA by EL-4 cells three to nine hours after treatment. CM from EL-4 cells treated with VES at 10-20 microgram/ml exhibited potent antiproliferative activity when tested in the TGF-beta-responsive mink lung cell (Mv1Lu) bioassay and showed reduced inhibitory effects when tested on TGF-beta receptor-negative mink lung (DRA-27) cells. CM from control-treated EL-4 cells exhibited no antiproliferative activity. The VES-induced antiproliferative activity was characterized as TGF-beta by neutralization analyses and immunoprecipitation of metabolically labeled proteins with TGF-beta-specific reagents. VES treatment of EL-4 cells had no effect on TGF-beta 1 mRNA expression while downregulating TGF-beta 3 mRNA expression. In summary, these studies showed that 0.1 microgram/ml VES enhanced cellular proliferation, in part, via increased IL-2 production, whereas 10-20 micrograms/ml VES inhibited cellular proliferation, in part, via the secretion of biologically active TGF-beta.

RRR-alpha-tocopheryl succinate enhances TGF-beta 1, -beta 2, and -beta 3 and TGF-beta R-II expression by human MDA-MB-435 breast cancer cells

The proliferation of MDA-MB-435 human breast cancer cells was inhibited by RRR-alpha-tocopheryl succinate (vitamin E succinate, VES). Conditioned media (CM) from VES growth-inhibited cells contained potent antiproliferative activity, part of which is contributed by transforming growth factor-beta (TGF-beta) isoforms. Antibody neutralization analysis, employing TGF-beta isoform-specific antibody reagents, showed that TGF-beta 1, -beta 2, and -beta 3 were present in the CM from VES-treated cells. Culturing MDA-MB-435 cells with VES did not alter the levels of constitutively expressed 2.4-kb TGF-beta 1, 3.0- and 4.0-kb TGF-beta 2, or 1.2- and 3.5-kb TGF-beta 3 mRNA transcripts. Inhibition of DNA synthesis by MDA-MB-435 cells was increased by combinations of suboptimal levels of VES and purified TGF-beta 1. VES-treated MDA-MB-435 cells exhibited enhanced binding of radiolabeled TGF-beta 1, and Western immunoblotting analyses showed that VES treatment enhanced TGF-beta type II receptor protein expression. TGF-beta type I receptor protein levels were not modified by VES treatments. Although the mRNA transcript for the 5.5-kb TGF-beta type II receptor was upregulated after four hours of treatment with VES, this treatment did not modify the 6.5-kb TGF-beta type I or the 6.5-kb TGF-beta type II receptor mRNAs. Results demonstrate that biologically active TGF-beta 1, -beta 2, -beta 3 and levels of TGF-beta type II receptor expressed by human breast cancer cells are enhanced by VES treatment.

RRR-alpha-tocopheryl succinate inhibits DNA synthesis and enhances the production and secretion of biologically active transforming growth factor-beta by avian retrovirus-transformed lymphoid cells

The RRR-alpha-tocopheryl succinate form of vitamin E, referred to as vitamin E succinate (VES), inhibits the proliferation of avian reticuloendotheliosis virus-transformed RECC-UTC4-1 (C4-1) lymphoblastoid cells in a dose-dependent manner in vitro. Analyses of conditioned medium (CM) from VES growth-inhibited cells revealed a potent antiproliferative activity. Characterization of the antiproliferative activity as transforming growth factor-beta (TGF-beta) was established by 1) growth inhibition of TGF-beta-responsive Mv1Lu mink lung and murine CTLL-2 cell lines, 2) a combination of physical characteristics including heat stability, acid stability, and Bio-Gel P-60 column chromatography elution profile, 3) neutralization of the antiproliferative activity by antibodies specific for TGF-beta, and 4) immunoprecipitation of metabolically labeled TGF-beta in CM from VES-treated C4-1 cells by use of TGF-beta-specific antibodies. Northern blot analyses of total cellular RNA revealed that VES does not alter the levels of constitutively expressed TGF-beta isoform-specific mRNAs; namely, VES does not alter the levels of the 3.9- and 4.1-kb TGF-beta 2 mRNAs, the 3.0-kb TGF-beta 3 mRNA, or the 2.5-, 2.7-, and 1.7-kb TGF-beta 4 mRNAs. The data show that VES inhibits C4-1 cell proliferation and induces the cells to produce and secrete active forms of TGF-beta, suggesting that one mechanism whereby VES inhibits C4-1 cell proliferation may be via the TGF-beta pathway for cellular growth control.

RRR-alpha-tocopheryl succinate inhibits the proliferation of human prostatic tumor cells with defective cell cycle/differentiation pathways

The RRR-alpha-tocopheryl succinate derivative of vitamin E, referred to as vitamin E succinate (VES), inhibits the proliferation of three metastatic human prostatic cancer cell lines, LNCaP, PC-3, and DU-145. LNCaP is a lymph node-derived androgen-sensitive prostate cell line; these cells are defective for response to transforming growth factor-beta (TGF-beta) but are normal for cell cycle-related tumor suppressor genes: p53 and retinoblastoma (Rb). PC-3 is a bone marrow-derived androgen-insensitive prostate cell line; these cells are defective for both p53 alleles but normal for both Rb alleles. DU-145 is a brain-derived androgen-insensitive prostate cell line; these cells are defective for both p53 and both Rb alleles. VES at 5, 10, and 20 micrograms/ml inhibited DNA synthesis in the three cell lines in a dose-dependent manner. Purified TGF-beta 1 at 1 ng/ml inhibited DNA synthesis of PC-3 cells within 24-72 hours and DU-145 cells at 72 hours but did not inhibit DNA synthesis of LNCaP cells. Previous studies in our laboratory showed that VES growth-inhibited tumor cells secrete biologically active antiproliferative factor TGF-beta s, suggesting that VES's mechanism of growth inhibition may involve the TGF-beta system of growth control.(ABSTRACT TRUNCATED AT 250 WORDS)

Vitamin E succinate induction of HL-60 cell adhesion: a role for fibronectin and a 72-kDa fibronectin-binding molecule

HL-60 cells, growing as single cells in suspension, exhibit marked cell-cell adhesion when treated for 24 hours with 10 micrograms/ml RRR-alpha-tocopheryl succinate, also called vitamin E succinate (VES). VES-induced cell-cell adhesion is dependent on divalent cations and a functional cytoskeleton and is protein mediated. Cell adhesion molecules CD11a/CD18, CD11b/CD18, CD29, and CD54 do not appear to be mediating VES-induced cell adhesion. HL-60 cells treated with VES adhere to fibronectin-coated plastic and secrete elevated levels of fibronectin. A 72-kDa fibronectin-binding membrane molecule was detected on VES-treated HL-60 cells, and antibodies to fibronectin were shown to inhibit VES-induced cell aggregation. VES induction of HL-60 cell-cell adhesion is proposed to result from increased amounts of extracellular fibronectin binding to VES-induced cell surface fibronectin-binding molecules.

Nutrition, immunology and cancer: an overview

There is epidemiological, laboratory and some clinical evidence that certain dietary factors play a role in either promoting or inhibiting cancer development. An understanding of the mechanisms whereby specific nutrients are having effects in the promotion or prevention of cancer is beginning to take shape. Research into nutrient effects on the expression of specific genes, especially cytokine and cytokine receptor expression, will help increase our basic knowledge of cancer biology. Since cytokines can either enhance or suppress both immune defense and cancer growth, increased understanding of nutrient effects on the cytokine network will be beneficial. The regulation of specific gene expression by specific nutrients, indeed, identifies a major frontier for present and future nutritional biologists.

Oligomerization and the Affinity of Maize Phosphoenolpyruvate Carboxylase for Its Substrate

When two different forms of phosphoenolpyruvate carboxylase (PEPC) from maize (Zea mays L.) leaves are present in an assay it is possible to estimate the ratio of Vmax to Km (V/K) for the two forms separately. This measure of the binding of the substrate by the enzyme permits evaluation of the effects of various treatments on the relative substrate-binding velocity of the enzyme. PEPC diluted 1/20 is present in a mixture of a tetrameric form with a high affinity for phosphoenolpyruvate and a dimeric form with a low affinity (M.-X. Wu, C.R. Meyer, K.O. Willeford, R.T. Wedding [1990] Arch Biochem Biophys 281: 324-329). Malate at 5 mM reduced (V/K)1,[mdash]the V/K of the probable tetrameric form[mdash]almost to zero, but reduced (V/K)2[mdash]the V/K of the probable dimer[mdash]by only about 80%. Glucose-6-phosphate (Glc-6-P) at 5 mM increased (V/K)1 to 155% of the control but had no effect on (V/K)2. Glycerol (20%) alone increased both V/Ks, and its effects are additive to the Glc-6-P effects, implying different mechanisms for activation by Glc-6-P and glycerol.

Effects of RRR-alpha-tocopheryl succinate on IL-1 and PGE2 production by macrophages

Vitamin E is thought to enhance immunity by increasing interleukin-1 (IL-1) production and by downregulating prostaglandin E2 (PGE2) synthesis. In an effort to understand the mechanism(s) whereby the form of vitamin E known as RRR-alpha-tocopheryl succinate [also called vitamin E succinate (VES)] ameliorates retrovirus-induced immune dysfunctions, peritoneal exudate cells (PECs) derived from normal chickens and avian and murine macrophage cell lines were used as in vitro model systems to test the effects of VES treatments on PGE2 and IL-1 production. Supernatants from PECs that were exposed to avian erythroblastosis virus (AEV) for 45 minutes exhibited a 256% increase in PGE2 levels compared with supernatants from replica cultures of PECs not exposed to AEV. Pretreatment of PECs with VES before exposure to AEV maintained PGE2 levels at normal control levels. VES treatment enhanced IL-1 production by avian (HD11) and murine (P388D1) macrophage cells, respectively. Supernatants from VES-treated HD11- and P388D1-stimulated cells contained IL-1 activity 196% and 385%, respectively, greater than that observed with supernatants from untreated control cells. On the basis of these studies, downregulation of retrovirus-induced PGE2 production and/or upregulation of IL-1 production by VES are potential mechanisms for VES amelioration of retrovirus-induced immune suppression.

RRR-alpha-tocopheryl succinate inhibits proliferation and enhances secretion of transforming growth factor-beta (TGF-beta) by human breast cancer cells

The RRR-alpha-tocopheryl succinate form of vitamin E inhibits the proliferation of estrogen receptor-positive and estrogen receptor-negative human breast cancer cell lines in a dose-dependent manner in vitro. Analyses of cell-conditioned medium from RRR-alpha-tocopheryl succinate growth-inhibited cells revealed the presence of a potent antiproliferative activity. Characterization of the antiproliferative activity as transforming growth factor-beta (TGF-beta) was established by 1) growth inhibition of the TGF-beta-responsive Mv1Lu-CCL-64 mink lung and murine CTLL-2 cell lines, 2) combination of physical characteristics including heat stability, acid stability, and Bio-Gel P-60 column chromatography elution profile, and 3) neutralization of the antiproliferative activity in the conditioned media by antibodies specific for TGF-beta.

RRR-alpha-tocopheryl succinate inhibition of lectin-induced T cell proliferation

The effect of RRR-alpha-tocopheryl succinate (VES) on lectin-induced chicken T cell proliferation was investigated. The T cell mitogens concanavalin A and phytohemagglutinin induce chicken thymic and splenic T cell proliferation. Addition of VES to the in vitro cultures inhibited T cell proliferation in a dose-dependent manner. Addition of VES to spleen cell cultures at different times after mitogen stimulation also suppressed T cell mitogenesis, suggesting that VES is not mediating its antiproliferative effects by interfering with ligand (mitogen)-receptor binding or early ligand-bound receptor-signaling events. Three lines of evidence suggest that the growth-inhibitory properties of VES are unique and may not involve antioxidant properties. 1) Three other forms of vitamin E, dl-alpha-tocopherol, d-alpha-tocopherol, and d-alpha-tocopherol acetate, do not inhibit the proliferation of mitogen-stimulated chicken spleen cells. 2) Spleen cells were treated with an inhibitor of nonspecific esterases to prevent the conversion of VES, which does not exhibit antioxidant properties to d-alpha-tocopherol, a lipid-soluble antioxidant. Treatment of spleen cells with the inhibitor did not affect VES's growth-inhibitory properties. 3) Trolox, a water-soluble vitamin E analogue with potent antioxidant properties and two lipid-soluble antioxidants, butylated hydroxyanisole and butylated hydroxytoluene, did not inhibit mitogen-induced T cell proliferation. Attempts to reverse VES's antiproliferative effects by addition of exogenous interleukin-2 or addition of sodium selenite, an enhancer of interleukin-2 receptors, failed. Acetylsalicylic acid had no effect on VES's inhibition of mitogen-activated T cell proliferation. These studies support the role of VES as a growth inhibitor of lectin-activated normal T cells in chickens.

RRR-alpha-tocopheryl succinate modulation of human promyelocytic leukemia (HL-60) cell proliferation and differentiation

HL-60 human promyelocytic leukemia cells can be induced to differentiate to granulocytes by retinoic acid and dimethyl sulfoxide or monocyte-macrophages by phorbol esters and 1,25-dihydroxyvitamin D3. These studies show that RRR-alpha-tocopheryl succinate (TS) inhibits HL-60 cell proliferation and induces the HL-60 cells to differentiate toward a functionally deficient macrophage-like cell. TS at (15 micrograms/ml) was found to suppress HL-60 cell proliferation by 63% and 89% at 24 and 48 hours, respectively. This suppression of proliferation, however, is not permanent and requires the presence of TS. HL-60 cells treated for 48 hours with TS (15 micrograms/ml) were found to be blocked in the G2/M phase of the cell cycle. HL-60 cells blocked in the G2/M cell cycle phase by TS expressed normal levels of the transferrin receptor. TS-treated HL-60 cells exhibited binucleated morphological appearance; however, the cells did not exhibit chemotaxis, phagocytosis, or changes in the expression of the cell surface markers, CD11a and CD18. However, HL-60 cells treated for 48 hours with TS (15 micrograms/ml) could be stimulated to produce superoxide radicals and exhibited nonspecific esterase activity, two characteristics of macrophages. These results suggest a role for TS as an antitumor proliferative agent and as a modifier of human leukemia cell differentiation.

Apparent role of adenosine diphosphoribosyl transferase in the development of Mytilus edulis and the inhibition of differentiation by ligands of the enzyme protein

The poly(ADP-ribose) polymerase or transferase (ADPRT) activity of developing embryos of Mytilus edulis increases with the progression of larval growth. ADPRT protein was partially purified from 2-hr-old embryos and identified by gel electrophoresis and immunotransblot, demonstrating cross-reactivity with anti-ADPRT IgG produced against the calf thymus enzyme. Two inhibitors of ADPRT, benzamide, competing with NAD at the nicotinamide binding site, and 6-amino-1,2-benzopyrone, which competes with DNA at the DNA binding site(s), both selectively arrest differentiation at the prodissoconch stage. The DNA site-oriented inhibitor, 6-amino-1,2-benzopyrone, has a much larger differentiation arresting effect than benzamide. The arrest of differentiation by 6-amino-1,2-benzopyrone is reversible. A probable ecotoxicity of ADPRT ligands on mussel differentiation is proposed.

RRR-alpha-tocopheryl succinate enhances T cell mitogen-induced proliferation and reduces suppressor activity in spleen cells derived from AEV-infected chickens

RRR-alpha-tocopheryl succinate was demonstrated to be a potent in vitro modulator of retrovirus-induced immune abnormalities. Spleen cells from avian erythroblastosis virus (AEV)-infected chickens exhibit suppressed T cell mitogen-induced proliferative responses and elevated levels of suppressor T cell activity. In vitro addition of RRR-alpha-tocopheryl succinate resulted in amelioration of these abnormalities. Antioxidants including Trolox (a water-soluble analogue of RRR-alpha-tocopherol with antioxidant properties) and a combination of butylated hydroxyanisole and butylated hydroxytoluene were able to restore immune functions to levels similar to those achieved with RRR-alpha-tocopheryl succinate treatment. Aspirin, an irreversible inhibitor of cyclooxygenase activity, was capable of ameliorating some of the AEV-induced immune dysfunctions. These studies suggest a role for the antioxidant functions of RRR-alpha-tocopheryl succinate in modulation of retrovirus-induced immune abnormalities.

MHC coded B-G homodimer and heterodimer heterogeneity among different chicken lines

Chicken lines were classified into six distinct groups based on expression of B-G molecules by peripheral red blood cells (RBC). In addition to the previously reported 48 kD subunits of homodimeric B-G molecules, subunits of 60, 40, and possibly 20 kD were detected in certain of the chicken lines. Several of the chicken lines express the previously reported 40 and 44 kD subunits of heterodimeric B-G molecules; however, B21B21 chickens expressed 44 kD subunits only and B5B5 and B13B13 chickens did not express detectable levels of any heterodimeric-related molecules. These studies provide further evidence for the polymorphic nature of the B-G antigens.

Immune abnormalities in avian erythroblastosis virus-infected chickens

Infection of animals with retroviruses frequently leads to immunosuppressed states. The immune status of chickens injected with the replication-defective avian erythroblastosis virus (AEV), with its naturally occurring subgroup B helper virus (avian erythroblastosis-associated virus; AEAV), was evaluated daily and compared to the immune status of age-matched uninfected control chickens. Spleen cells from AEV-infected chickens gave depressed responses to concanavalin A, phytohemagglutinin, and pokeweed mitogen beginning 3 days after injection of the virus and continuing until death. Spleen cells from AEV-infected chickens suppressed the T-cell mitogen-induced blastogenic responses of spleen cells from uninfected chickens. The ability of spleen cells from infected chickens to suppress mitogen-induced blastogenic responses of spleen cells from normal chickens in coculture was transient beginning 4 days following viral inoculation, reaching peak levels of suppression on day 7 and disappearing by day 12. Cytolysis of splenic cells from AEV-infected chickens with polyclonal anti-T-cell-serum removed the suppressor activity. Addition of conditioned medium rich in T-cell growth factor resulted in a partial restoration of the blastogenic responsiveness of splenic cells from 6-day post-AEV-infected chickens. Addition of exogenous T-cell growth factor had no effect on the suppressed blastogenic responsiveness of spleen cells from 12-day post-AEV-infected chickens, and it had no effect on coculture suppression. In addition to suppressed T-cell responses to polyclonal mitogen-induced proliferation in vitro and transiently expressed T-suppressor cells, thymic atrophy and structural disruption was observed in AEV-infected chickens.

Effect of sodium bicarbonate on racing Standardbreds

Twenty-two Standardbred horses in race training were used in a crossover experiment to determine the effect of oral sodium bicarbonate (NaHCO3) administration on performance and metabolic responses to a 1.6-km (1-mile) race. Horses were paired and one horse in each pair was treated with either NaHCO3 (300 mg/kg BW) or a placebo, 2.5 h before they raced against each other. Each horse was scheduled to compete in two races, approximately 1 wk apart, one on each treatment. Horses always raced in the same pairs. Fourteen horses successfully completed both races. Jugular blood samples were obtained 1.5 h after treatment (rest), immediately before racing, 5 min post-race and 15 min post-race. In six horses, blood samples also were obtained 30 min post-race. Race times averaged 1.1 s faster after NaHCO3 treatment (P less than .1). Sodium bicarbonate treatment also elevated blood pH (P less than .05). In the horses sampled 15 and 30 min post-race, blood lactate disappearance was faster with the NaHCO3 treatment (P less than .05). The NaHCO3 may delay the fatigue precipitated by i.m. acidosis. Because other factors may limit performance (musculoskeletal soundness, cardiovascular and respiratory ability), NaHCO3 would not be expected to enhance the performance of all horses. However, the effect of NaHCO3 on lactate clearance may have implications for all intensively worked horses; because lactate and the associated hydrogen ions are believed to cause muscle damage and soreness, any mechanism to increase their removal rate could benefit the equine athlete.

Growth-inhibitory effects of vitamin E succinate on retrovirus-transformed tumor cells in vitro

Vitamin E succinate inhibited proliferation of C4#1 cells, an established avian retrovirus [reticuloendotheliosis virus (REV)]-transformed immature lymphoid tumor cell line, in a dose-dependent manner. The cytostatic effects of vitamin E succinate were reversible in that treated cells regained their ability to divide after vitamin E succinate removal. Possible mechanism(s) for the antiproliferative actions of vitamin E succinate were investigated. Analyses of C4#1 cell surface membrane antigen profiles and morphology indicated that vitamin E succinate was not inducing differentiation of the tumor cells to a more mature, differentiated, nonproliferative state. Five antioxidants, including a synthetic analogue of vitamin E, Trolox, as well as the active vitamin form, DL-alpha-tocopherol, were incapable of inhibiting C4#1 tumor cell growth, indicating that a mechanism of action other than or in addition to functions as an antioxidant may be operating. Cell cycle analyses suggested that C4#1 tumor cells treated with vitamin E succinate were blocked in the G0G1/early S phases of the cell cycle. Tumor growth arrested by vitamin E succinate did not affect the expression of the REV-encoded oncogene, v-rel, at either the RNA or protein level. These studies demonstrated that vitamin E, in the form of vitamin E succinate, inhibited the growth of retrovirus-transformed tumor cells in vitro and suggested that the antiproliferative effects of vitamin E succinate did not involve antioxidant properties but rather, as yet, unidentified mechanisms leading to cell cycle blockage.

Modulation of immune suppression and enhanced tumorigenesis in retrovirus tumor challenged chickens treated with vitamin E

Vitamin E(dl-alpha-tocopherol) dissolved in ethanol with polyethylene glycol as the vehicle and administered by intraperitoneal injections of 0.1 mg/gm body weight at two day intervals, was demonstrated to be a potent immunomodulating reagent in young chickens challenged with avian reticuloendotheliosis virus-transformed tumor cells. Vitamin E treatment enhanced the mitogen-induced proliferative responses of spleen cells from age matched, unchallenged chickens; reduced the tumor cell-induced suppression of host splenic lymphocyte mitogen responses; and eliminated tumor cell-induced suppressor cell activity. However, inspite of an improved immune status the vitamin E treated-tumor cell challenged chickens exhibited enhanced tumorigenesis.

Characterization of two distinct disulfide-linked B-G molecules in the chicken

Alloantisera specific for B-G antigens recognized a complex of molecules of apparent molecular weights of 90 and 98 Kd under nonreducing conditions and molecules of 40, 44, and 48 Kd under reducing conditions on both embryo- and adult-derived peripheral red blood cells (RBC). The chicken B-G molecules produced a unique two-dimensional "diagonal" pattern. Two antisera permitted the characterization of the complex B-G molecular profile as a homodimer composed of 48-Kd subunits and as a heterodimer composed of 40- and 44-Kd subunits. A rabbit antiserum produced against B-G molecules preferentially recognized the 48-Kd reduced molecules, suggesting that the 90-Kd molecule was a homodimer composed of two 48-Kd molecules. One B-G reagent was capable of recognizing only the 98-Kd nonreduced B-G molecule that gave rise to 40- and 44-Kd molecules under reducing conditions, suggesting that the 98-Kd molecule was a heterodimer composed of 44- and 40-Kd subunits. Adult chicken B-G2 molecules produced a variety of two-dimensional isoelectric focusing/sodium dodecyl sulfate-polyacrylamide gel electrophoresis (IEF/SDS-PAGE) patterns depending on the characteristics of the reagent employed in the immunoprecipitation. B-G molecules were immunoprecipitated from primitive and definitive chicken RBCs but not from any nonerythroid cells tested. B-G molecules were not expressed by avian erythroblastosis virus (AEV)-transformed erythroleukemia cells, nor were they induced to appear with butyric acid-induced erythroid differentiation.

Characterization of different B-F (MHC class I) molecules in the chicken

B-F alloantisera recognized distinct 45-Kd molecules on peripheral red blood cells (RBC) from embryonic chickens and heterogeneous molecules of approximately 40 to 44 Kd on peripheral RBC from adult chickens, provisionally referred to as type 1 and type 2, respectively. Type 2 molecules migrated to the basic end of isoelectric focusing gels, exhibited multiple isomorphic variants, and were associated with a smaller polypeptide of approximately 11 to 12 Kd assumed to be beta-2-microglobulin. Type 1 molecules migrated to the acidic end of isoelectric focusing gels, exhibited limited heterogeneity, and were not associated with a smaller polypeptide. Type 1 and type 2 molecules were also shown to be distinct by peptide mapping and serological analyses. In addition, two distinct molecular-weight forms of the type 2 molecules were distinguished, provisionally referred to as 2A (45 Kd) and 2B (42 Kd). In vivo-derived avian erythroblastosis virus (AEV)-transformed erythroleukemia cells expressed type 2A molecules. In vitro-derived AEV-transformed erythroleukemia cells expressed very low levels of B-F molecules; however, they expressed type 2B molecules when induced to differentiate. Normal bursa-derived lymphoid cells expressed type 2A molecules, whereas normal thymus-derived lymphoid cells expressed type 2B molecules. Cloned reticuloendotheliosis virus (REV)-transformed immature lymphoid cells expressed either type 2A or type 2B molecules.

Impact of commercial eating on nutrient adequacy

The purpose of this study was to investigate the impact of eating away from home (at commercial establishments) on nutrient adequacy by examining frequency of eating away from home, the nutritional value of foods eaten both away and at home, and the nutritional adequacy of the daily diets of individuals. Data from 3,500 individuals, 15 years of age or older, interviewed in the fall quarter of the 1977-78 Nationwide Food Consumption Survey were used. Results indicate that although the nutrient density of food eaten away from home was lower than that of food eaten at home, the persons studied did not eat out frequently enough to influence the adequacy of their diets significantly. The low nutrient density of food eaten away from home does suggest, however, that individuals could be putting themselves at risk of some nutrient inadequacies (particularly of calcium and vitamins A, B-6, and C) or of caloric excess if they substantially increase their frequency of eating away from home. Teenagers and senior citizens seem most vulnerable to potential nutritional inadequacies.

Perception of orientation of motion as affected by change in divergence of texture, change in size, and in velocity

When there is relative motion between an observer and a textured surface such as the ground, motion-related visual information is available about the orientation of the surface through vergence of the paths of the elements of the texture, change in their sizes and in their velocities. This experiment determined the perceptual effectiveness of each variable in foveal and peripheral viewing for producing perceptions of three-dimensional motion. The three variables were electronically separated and displayed singly, in all possible pairs, and all together. Subjects communicated their perceptions of degree of perceived surface tilt at the top, bottom, and middle of the display for the eight different combinations of variables because, during pilot work perceived surface bendings were frequently noted where top, bottom, and middle appeared tilted to different extents. All three variables can lead to relatively reliable perceptions of perceived orientation of the plane of motion, with change in velocity being the most powerful determiner. Change in size was the weakest. Certain combinations can lead to perceptions of extreme warping and should be avoided in motion displays. Subjects consistently underestimate the amount of simulated tilt. Foveal viewing was more accurate than peripheral viewing but peripheral performance was adequately consistent as an input channel for some orientation tasks.