bluuebunny/crossref_metadata_2025 huggingface dataset:
Magnesium Sulfate as a Second-Line Tocolytic Agent for Preterm Labor: A Randomized Controlled Trial in Kyushu Island
Authors: Kawagoe Yasuyuki , Sameshima Hiroshi , Ikenoue Tsuyomu , Yasuhi Ichiro , Kawarabayashi Tatsuhiko
Published: June 2011

Objectives. We evaluated the efficacy of magnesium sulfate as a second-line tocolysis for 48 hours.Materials and Methods. A multi-institutional, simple 2-arm randomized controlled trial was performed. Forty-five women at 22 to 34 weeks of gestation were eligible, whose ritodrine did not sufficiently inhibit uterine contractions. After excluding 12 women, 33 were randomly assigned to either magnesium alone or combination (ritodrine and magnesium). The treatment was determined as effective if the frequency of uterine contraction was reduced by 30% at 48 hours of the treatment.Results. After magnesium sulfate infusion, 90% prolonged their pregnancy for >48 hours. Combination therapy was effective in 95% (18/19), which was significantly higher than 50% (7/14) for magnesium alone.Conclusion. This randomized trial revealed that combination therapy significantly reduced uterine contractions, suggesting that adjuvant magnesium with ritodrine is recommended, rather than changing into magnesium alone, when uterine contractions are intractable with ritodrine infusion.
Circulating Tumor Cells as Biomarkers in Prostate Cancer
Authors: Danila Daniel C. , Fleisher Martin , Scher Howard I.
Published: June 2011

Unmet needs in prostate cancer drug development and patient management are the ability to monitor treatment effects and to identify therapeutic targets in a tumor at the time treatment is being considered. This review focuses on establishing analytically valid biomarkers for specific contexts of use in patients with castration-resistant prostate cancer (CRPC), emphasizing a biomarker currently in clinical use, circulating tumor cells (CTC). The FDA Critical Path provides a road map for these investigations, which, if followed, will facilitate the incorporation of these types of assays into clinical decision-making. CTC enumeration at baseline and post-treatment is prognostic of survival, with no threshold effect, and the shedding of cells into the circulation represents an intrinsic property of the tumor, distinct from extent of disease. The clinical utility of monitoring CTC changes with treatment, as an efficacy-response surrogate biomarker of survival, is currently being tested in large phase III trials, with the novel antiandrogen therapies abiraterone acetate and MDV3100. Molecular determinants can be identified and characterized in CTCs as potential predictive biomarkers of tumor sensitivity to a therapeutic modality. Additionally, we discuss novel technologies to enrich and characterize CTCs from more patients, the potential clinical uses of CTCs in determining prognosis and monitoring treatment effects, and CTCs as a source of tissue to identify predictive markers of drug sensitivity to guide treatment selection. Prospective studies, designed around the biomarker itself and the specific clinical context for which it is applied, are needed to further assess the role of these and novel markers in clinical practice. Clin Cancer Res; 17(12); 3903–12. ©2011 AACR.
Emerging Roles of Protein Kinase D1 in Cancer
Authors: Sundram Vasudha , Chauhan Subhash C. , Jaggi Meena
Published: June 2011

Protein kinase D1 (PKD1) is a serine-threonine kinase that regulates various functions within the cell, including cell proliferation, apoptosis, adhesion, and cell motility. In normal cells, this protein plays key roles in multiple signaling pathways by relaying information from the extracellular environment and/or upstream kinases and converting them into a regulated intracellular response. The aberrant expression of PKD1 is associated with enhanced cancer phenotypes, such as deregulated cell proliferation, survival, motility, and epithelial mesenchymal transition. In this review, we summarize the structural and functional aspects of PKD1 and highlight the pathobiological roles of this kinase in cancer. Mol Cancer Res; 9(8); 985–96. ©2011 AACR.
Inactivation of AR/TMPRSS2-ERG/Wnt Signaling Networks Attenuates the Aggressive Behavior of Prostate Cancer Cells
Authors: Li Yiwei , Kong Dejuan , Wang Zhiwei , Ahmad Aamir , Bao Bin , Padhye Subhash , Sarkar Fazlul H.
Published: June 2011

The development of prostate cancer and its progression to castrate-resistant prostate cancer (CRPC) after antiandrogen ablation therapy are driven by persistent biological activity of androgen receptor (AR) signaling. Moreover, studies have shown that more than 50% of human prostate cancers overexpress ERG (v-ets avian erythroblastosis virus E26 oncogene related gene) due to AR-regulated TMPRSS2-ERG fusion gene. However, the reported roles of TMPRSS2-ERG fusion in cancer progression are not clear. In this study, we investigated the signal transduction in the AR/TMPRSS2-ERG/Wnt signaling network for studying the aggressive behavior of prostate cancer cells and further assessed the effects of BR-DIM and CDF [natural agents-derived synthetic formulation and analogue of 3,3′-diindolylmethane (DIM) and curcumin, respectively, with improved bioavailability] on the regulation of AR/TMPRSS2-ERG/Wnt signaling. We found that activation of AR resulted in the induction of ERG expression through TMPRSS2-ERG fusion. Moreover, we found that ERG overexpression and nuclear translocation activated the activity of Wnt signaling. Furthermore, forced overexpression of ERG promoted invasive capacity of prostate cancer cells. More important, we found that BR-DIM and CDF inhibited the signal transduction in the AR/TMPRSS2-ERG/Wnt signaling network, leading to the inactivation of Wnt signaling consistent with inhibition of prostate cancer cell invasion. In addition, BR-DIM and CDF inhibited proliferation of prostate cancer cells and induced apoptotic cell death. On the basis of our findings, we conclude that because BR-DIM and CDF downregulate multiple signaling pathways including AR/TMPRSS2-ERG/Wnt signaling, these agents could be useful for designing novel strategies for the prevention and/or treatment of prostate cancer. Cancer Prev Res; 4(9); 1495–506. ©2011 AACR.
Phase I Randomized, Double-Blind Pilot Study of Micronized Resveratrol (SRT501) in Patients with Hepatic Metastases—Safety, Pharmacokinetics, and Pharmacodynamics
Authors: Howells Lynne M. , Berry D.P. , Elliott P.J. , Jacobson E.W. , Hoffmann E. , Hegarty B. , Brown K. , Steward W.P. , Gescher A.J.
Published: June 2011

The phytochemical resveratrol has undergone extensive preclinical investigation for its putative cancer chemopreventive properties. Low systemic availability of the parent compound due to rapid and extensive metabolism may confound its usefulness as a potential agent to prevent malignancies in organs remote from the site of absorption. Micronization allows increased drug absorption, thus increasing availability. Here we describe a pilot study of SRT501, micronized resveratrol, given as 5.0 g daily for 14 days, to patients with colorectal cancer and hepatic metastases scheduled to undergo hepatectomy. The purpose of the study was to assess the safety, pharmacokinetics, and pharmacodynamics of the formulation. SRT501 was found to be well tolerated. Mean plasma resveratrol levels following a single dose of SRT501 administration were 1,942 ± 1,422 ng/mL, exceeding those published for equivalent doses of nonmicronized resveratrol by 3.6-fold. Resveratrol was detectable in hepatic tissue following SRT501 administration (up to 2,287 ng/g). Cleaved caspase-3, a marker of apoptosis, significantly increased by 39% in malignant hepatic tissue following SRT501 treatment compared with tissue from the placebo-treated patients. SRT501 warrants further clinical exploration to assess its potential clinical utility. Cancer Prev Res; 4(9); 1419–25. ©2011 AACR.
Endocrine Outcome in Long-Term Survivors of Childhood Brain Tumors
Authors: Shalitin Shlomit , Gal Moran , Goshen Yacob , Cohen Ian , Yaniv Isaac , Phillip Moshe
Published: June 2011

Aim: To evaluate the rates of endocrine abnormalities in survivors of childhood brain tumors and identify risk factors. Methods: The medical charts of patients were reviewed for background, disease-related and treatment-related data. Endocrine dysfunction was determined by clinical and laboratory evaluation. Results: The study group included 114 patients with a mean age of 15.57 ± 5.93 years. Mean age at brain tumor diagnosis was 7.07 ± 5.42 years, and mean follow-up was 12.8 ± 6.25 years. Fifty-seven patients (50%) had an endocrine abnormality. The occurrence of several endocrine abnormalities was significantly associated with cranial irradiation and age <16 years at tumor diagnosis. The presence of growth hormone deficiency (n = 40) was associated with cranial or spinal irradiation, younger age and prepubertal stage at tumor diagnosis; the presence of hypogonadotropic hypogonadism (n = 9) was associated with prepubertal stage at diagnosis, and hypothyroidism (n = 23) was associated with cranial irradiation. Hypocortisolism was diagnosed in 9 patients, short stature in 20 patients and obesity in 8 male patients. Patients with early puberty (n = 19) and an abnormal lipid profile (n = 15) were significantly younger at tumor diagnosis than patients without these disorders. Conclusions: Childhood brain tumor survivors are at increased risk of late endocrine effects, particularly those treated with cranial radiation and diagnosed at a younger age. The frequency of hormonal deficits increases with time, warranting lifelong surveillance.
Characterization of Fpr-rs8, an Atypical Member of the Mouse Formyl Peptide Receptor Gene Family
Authors: Tiffany H. Lee , Gao Ji-Liang , Roffe Ester , Sechler Joan M.G. , Murphy Philip M.
Published: June 2011

The formyl peptide receptor gene family encodes G protein-coupled receptors for phagocyte chemoattractants, including bacteria- and mitochondria-derived N-formylpeptides. The human family has 3 functional genes, whereas the mouse family has 7 functional genes and 2 possible pseudogenes (ΨFpr-rs2 and ΨFpr-rs3). Here we characterize ΨFpr-rs2, a duplication of Fpr-rs2. Compared to Fpr-rs2, the ΨFpr-rs2 ORF is 186 nucleotides shorter but 98% identical. Due to a deletion and frame shift, the sequences lack homology from amino acid 219–289. Both transcripts were detected constitutively in multiple immune organs; however, ΨFpr-rs2 was consistently less abundant than Fpr-rs2. LPS induced expression of ΨFpr-rs2, but not Fpr-rs2, in spleen and bone marrow. Both transcripts were detected constitutively in thioglycollate-elicited peritoneal neutrophils, whereas only Fpr-rs2 was detected in thioglycollate-elicited peritoneal macrophages. Both transcripts were induced in LPS-stimulated macrophages. ΨFpr-rs2-GFP fusion protein appeared in cytoplasm but not plasma membrane of transfected HEK 293 cells, whereas Fpr-rs2-GFP labeled only plasma membrane. Survival of ΨFpr-rs2–/– mice was 33% shorter than that of wild-type and heterozygous littermates (p < 0.05), but no signature pathology was identified. Since ΨFpr-rs2 is expressed in phagocytes and regulated by bacterial products, and may affect longevity, we propose renaming it Fpr-rs8, an atypical member of the formyl peptide receptor gene family.
Clinical Characteristics of Molluscum Contagiosum in Children in a Private Dermatology Practice in the Greater Paris Area, France: A Prospective Study in 661 Patients
Authors: Osio A. , Deslandes E. , Saada V. , Morel P. , Guibal F.
Published: June 2011

Background: Series regarding the clinical characteristics of molluscum contagiosum (MC) are retrospective and concern small defined populations seen in a hospital setting. Methods: We prospectively studied patients under 15 years of age with MC seen in 25 private dermatology practices in the greater Paris area during 1 year. Results: Six hundred fifty patients were included. The mean age was 6 years. Of the patients, 30.5% had had MC in the past, 53% had 5–20 MC, 43% had a history of atopic dermatitis (AD), 5% were using topical steroids, 25.5% had coexistent AD, 13% had giant MC (>5 mm), 21% had inflammatory MC, and 19% had MC surrounded by eczema. Bathing with siblings was associated with a higher number of MC. A history of AD was associated with the presence of MC surrounded by eczema. The use of topical steroids was associated with a higher risk of relapse. There was no relation between environmental factors (MC in surrounding people, going to the swimming pool, sports practice) and the number of lesions or between environmental factors and the number of recurrences. Conclusion: Atypical lesions are frequent. Bathing with siblings is associated with a higher number of MC. Topical steroid use increases the risk of relapses. AD prevalence is higher than in the general population.
Vascular wall growth control: the role of the endothelium.
Authors: Schwartz S M , Gajdusek C M , Selden S C
Published: June 2011

The current state of our knowledge of the control of endothelial growth and the role of endothelial injury in the pathogenesis of atherosclerosis can be summarized as follows: 1. Endothelial cells can be grown in plasma-derived serum in the absence of exogenous growth factors. This is quite different from the growth requirements of most other nontransformed cells. These factors may, however, prolong replicative life span and increase the ability of endothelium to grow at sparse density. The relevance of these phenomena to the control of endothelial growth in vivo is unclear. There is no evidence that exogenous growth factors are required for wound edge regeneration. In view of the relative lack of growth factor requirements, it is intriguing to consider the possibility that the critical control factor for endothelial cell growth is cell contact. 2. Endothelial cell regeneration may be dependent on endothelial cell motility. The nature of this relationship may be important in controlling the ability of the endothelium to regenerate itself under different flow conditions around lesions or in different parts of the vessel tree and in determining the ability of the endothelium to respond to changes in the connective tissue overlying lesions. 3. Endothelial cells in vivo are able to regenerate small areas of denudation extremely rapidly. This process may be sufficiently rapid to permit the endothelium to replace dying cells as they are being lost, resulting in desquamation without denudation. 4. We have little evidence for endothelial denudation either spontaneously or in response to atherosclerosis risk factors until after lesion formation has begun. This does not rule out the possibility that small, repeated, transient episodes of denudation occur and play a role in the initiation of atherosclerotic lesions. It is important, however, to begin considering the role of nondenuding injuries in atherosclerosis. 5. The fact that thrombosis occurs in atherosclerosis implies an eventual breakdown of endothelial integrity. The mechanism of that breakdown remains unknown. 6. Finally, there is the question of interactions between smooth muscle cells and endothelial cells at the level of growth control. This includes the evidence that there is a critical amount of endothelium that must be lost before lesion formation is stimulated and the recent evidence that endothelial cells produce substances able to regulate growth of smooth muscle cells.
Acetoacetylated lipoproteins used to distinguish fibroblasts from macrophages in vitro by fluorescence microscopy.
Authors: Pitas R E , Innerarity T L , Weinstein J N , Mahley R W
Published: June 2011

We have developed a procedure for labeling lipoproteins with the fluorescent probe 3,3'-dioctadecylindocarbocyanine (Dil) and have used Dil-labeled native and acetoacetylated lipoproteins to differentiate macrophages from fibroblasts in mixed cell culture. Lipoproteins labeled with this probe were suitable for the direct viewing of their binding and internalization by cells in vitro. The labeling technique has been applied to human low density lipoproteins (LDL) and to two canine cholesterol-induced lipoproteins: apo-E HDLc, which contain only the E apoprotein (apo-E), and beta-migrating, very low density lipoproteins (beta-VLDL), which contain apo-B and apo-E. The Dil-labeled lipoproteins showed specific high affinity binding to human fibroblasts via the LDL (apo-B, -E) receptors. The equilibrium dissociation constant for the binding of Dil-labeled apo-E HDLc and LDL were the same as for the respective native lipoproteins. The specific binding of Dil-labeled LDL and apo-E HDLc was further substantiated by fluorescence microscopy. When an excess of native (non-fluorescent) lipoproteins was added to the Dil-labeled lipoproteins, essentially no fluorescently labeled lipoproteins were seen associated with the cells. The Dil-labeled LDL, apo-E HDLc, and beta-VLDL, which were bound to the cells at 4 degrees C, were associated with the cell surface and were often observed in linear arrays. Cells that were either incubated with Dil-labeled lipoproteins at 4 degrees C and subsequently heated to 37 degrees C or incubated with the Dil-labeled lipoproteins at 37 degrees C showed internalized perinuclear fluorescence. When Dil-labeled LDL, apo-E HDLc, or beta-VLDL were treated with diketene to acetoacetylate their lysine residues, and then were incubated at 37 degrees C with mixtures of fibroblasts and mouse peritoneal macrophages in culture, the fibroblasts did not become fluorescently labeled. The macrophages became highly fluorescent, however. The acetoacetylation inhibited the interaction of the lipoproteins with the apo-B, -E receptors of fibroblasts and stimulated their uptake by macrophages. The use of fluorescently labeled native lipoproteins and chemically modified lipoproteins may allow the functional differentiation of macrophages from other cell types (e.g., fibroblasts and smooth muscle cells) in the arterial wall. This differentiation may be useful in determining the origin of the lipid-laden foam cells of atherosclerotic lesions.
Stimulation of cholesteryl ester synthesis in macrophages by extracts of atherosclerotic human aortas and complexes of albumin/cholesteryl esters.
Authors: Goldstein J L , Hoff H F , Ho Y K , Basu S K , Brown M S
Published: June 2011

Cholesteryl ester-rich particles extracted from human atherosclerotic plaques were shown to increase the rate of incorporation of [14C]oleate into cholesteryl [14C]oleate and to cause massive accumulation of cholesteryl esters in monolayers of mouse peritoneal macrophages. This stimulation showed saturation kinetics and susceptibility to competition by polyanions (polyinosinic acid, fucoidin, dextran sulfate), suggesting that cell surface binding was required. Cellular uptake and lysosomal hydrolysis of the cholesteryl esters were also required, as indicated by the finding that stimulation of cholesteryl ester formation was prevented by the lysosomal inhibitor, chloroquine. The cholesterol esterification-stimulating activity of the aortic extracts was excluded on a 2% agarose column and floated in the density range of 1.006 to 1.063 g/ml. Cholesterol-rich extracts from human adrenal glands and liver did not stimulate cholesteryl ester formation in macrophages. The aortic extracts did not stimulate cholesteryl ester synthesis in human fibroblasts. Complexes of 125I-labeled albumin and cholesteryl linoleate formed in vitro were taken up and degraded in macrophages, but not in fibroblasts, by a process resembling the uptake of the aortic extracts. The current data suggest that macrophages express mechanisms for internalizing certain types of cholesteryl ester-rich lipid/protein complexes, including those present in atherosclerotic plaques.
Risk factors and raised atherosclerotic lesions in coronary and cerebral arteries. Statistical analysis from the Oslo study.
Authors: Holme I , Enger S C , Helgeland A , Hjermann I , Leren P , Lund-Larsen P G , Solberg L A , Strong J P
Published: June 2011

In 1972-1973, about 16,200 men living in Oslo, aged 40 to 49 years, were examined for cardiovascular disease, and had a number of coronary risk factors measured. This report gives the results of 129 autopsied cases with regard to the association between raised atherosclerotic lesions in coronary and cerebral arteries and various coronary risk factors. For coronary raised lesions, the high density lipoprotein (HDL) cholesterol ratio was the most significant risk factor. Systolic blood pressure and total serum cholesterol were also significantly associated. Physical activity at work and at leisure, nonfasting triglycerides, and cigarette smoking did not show a significant association with coronary artery raised lesions. The association between total serum cholesterol and systolic blood indicates that total serum cholesterol may be more important than systolic pressure in the synergism affecting the development of coronary atherosclerosis. For cerebral artery raised lesions, blood pressure was the most important risk factor, even though serum cholesterol was highly associated with the lesions. The interaction analysis also suggested that blood pressure was more important than serum cholesterol in the synergism.
Local aortic histamine metabolism and albumin accumulation. Differences between blue and white areas.
Authors: Owens G K , Hollis T M
Published: June 2011

Relationships between histamine metabolism, histamine content, and albumin accumulation were examined in Evans blue dye stained areas (blue) and unstained (white) areas of normal canine aortas. Results indicated that, while no differences existed in histamine methyltransferase-mediated catabolism, both histidine decarboxylase-mediated histamine synthesis and the histamine content of blue regions were significantly greater (p less than 0.005) than in contiguous white areas. Blue areas also showed significantly higher fluorescein-labeled albumin accumulation than white areas. By multiple regression analysis, a significant relationship (r = 0.81) was obtained between local aortic albumin accumulation and combined influences of local histidine decarboxylase activity and histamine content. The best predictor in this case was the local histidine decarboxylase activity. These data indicate that blue areas, believed to represent areas of spontaneous hemodynamic-induced vascular injury, have a larger nascent histamine pool than do contiguous white areas and that the distribution of histamine and histamine synthesis in the aorta is highly variable depending on the region examined. The data also suggest that local aortic histamine synthesis in blue areas may play a significantly role in mediation of the increased albumin accumulation observed in these regions.
Multivariate analyses of serum apolipoproteins and risk factors in relation to acute myocardial infarction.
Authors: Fager G , Wiklund O , Olofsson S O , Wilhelmsen L , Bondjers G
Published: June 2011

In 25 middle-aged infarction survivors and 76 corresponding controls, representative for a well-defined community, multivariate analysis was used to evaluate whether serum apolipoproteins were better discriminators of infarction survivors than serum lipids and other risk factors. Levels of serum cholesterol and triglycerides, alphalipoprotein cholesterol, apolipoproteins A-I, A-II, B, and D, as well as tobacco smoking and other risk factors, were included. In descending order, serum apo A-II levels (t(b) = -3.12, p = 0.002), tobacco consumption (t(b) = 2.64, p = 0.010), and serum triglycerides (t(b) = 2.06, p = 0.042) contributed significantly to the multiple regression on myocardial infarction (R = 0.53, p = 0.00001). When entered into ka discriminant function, these three variables gave a good separation between survivors and controls. Of the survivors, 50% were above the 90th percentile inthe control group. The relative prevalence of infarction increased continuously with increasing values of the function from zero to more than 6 times the average. Serum apo A-II levels alone were almost as good in separating cases and controls. From this study, we concluded that, among apolipoproteins, apo A-II seems to be a more sensitive discriminator of infarction survivors than other risk factors.
Changes in aortic lysyl oxidase activity in diet-induced atherosclerosis in the rabbit.
Authors: Kagan H M , Raghavan J , Hollander W
Published: June 2011

This study assessed the responses of lysyl oxidase, the enzyme that initiates covalent crosslinking in elastic and collagen, by studying the aortic tissue of rabbits after arteriosclerosis had been induced by diet. Rabbits in the experimental group were fed an atherogenic diet of rabbit chow supplemented with 8% peanut oil and 2% cholesterol for varying periods of time, while the control group was fed only rabbit chow. Lysyl oxidase activity was found to be distributed throughout the length of the thoracic and abdominal aortas of the normal rabbits, However, rabbits fed the atherogenic diet showed marked increases in enzyme in the aortic arch, a change that was initially evident after 30 days and became greatest (2.5 times that of the controls) after 90 days. Enzyme activity in the study rabbits increased only minimally in the abdominal aortic wall. Aortic prolyl hydroxylase activity measured after 60 days of feeding changed in degree and manner similar to lysyl oxidase activity. These region-specific changes in enzyme activities correlated with the distribution and severity of aortic lesions in this model of the disease. Lysyl oxidase activity increased dramatically in this model of atherosclerosis, suggesting that this extracellular enzyme activity may prove to be a vulnerable and accessible point of control of the fibrotic response in atherosclerosis.
Effects of oscillatory mechanical disturbance on macromolecular uptake by arterial wall.
Authors: Chien S , Lee M M , Laufer L S , Handley D A , Weinbaum S , Caro C G , Usami S
Published: June 2011

Transport of 125I-albumin by isolated segments of canine common carotid arteries was studied in vitro at zero transmural pressure. Sinusoidal oscillatory variations in length (peak change 4%) for 15 minutes at frequencies of 5 and 10 Hz caused 40% increase in 125I-albumin uptake, and also a 30% increase in the apparent luminal surface area. Changes in the duration and frequency of oscillation indicate that the total number of oscillations (= frequency X duration) was the critical parameter in causing these effects. The increase in apparent luminal surface area was correlated with regional flattening of the internal elastic lamina and the overlying endothelial cells, as demonstrated by transmission and scanning electron microscopy. Endothelial vesicles were counted with the aid of ruthenium red as a postfixation extracellular marker. The ratio of unstained free vesicles to total vesicles averaged 0.083 in the control state and decreased slightly to 0.070 after oscillation. Although the decrease in free vesicle population indicated an acceleration of vesicle diffusion, our theoretical computations showed that the resulting increase in vesicle flux was negligible. The increase in 125I-albumin uptake by the artery following mechanical oscillation is mainly attributable to the increase in apparent luminal surface area.
Responses of serum lipoproteins to dietary cholesterol and type of fat in the baboon.
Authors: McGill H C , McMahan C A , Kruski A W , Kelley J L , Mott G E
Published: June 2011

We examined the effects of dietary cholesterol (less than 0.01 and 1.7 mg/Kcal) and type of fat (saturated, coconut oil; polysaturated, corn oil) on very low density plus low density lipoprotein (VLDL + LDL) and high density lipoprotein (HDL) cholesterol in 24 young baboons (12 male, 12 female) Paplo sp.) in a crossover design experiment. The oils contributed 40% of calories. Total serum cholesterol concentration on the low cholesterol-polyunsaturated fat diet averaged 120 mg/dl; on the high cholesterol-saturated fat diet, 245 mg/dl; and on the other two cholesterol-fat diet combinations, about 200 mg/dl. There was a significant interaction between cholesterol and type of fat in their effects on VLDL + LDL cholesterol, but not in their effects on HDL cholesterol. Dietary cholesterol elevated VLDL + LDL cholesterol when fed with both types of fat, but elevated it more when fed with polyunsaturated fat than with saturated fat. Saturated fat elevated VLDL + LDL cholesterol when dietary cholesterol was low, but not when dietary cholesterol was high. Saturated fat consistently elevated HDL cholesterol more than did dietary cholesterol. The response of apolipoprotein B concentrations to dietary components was similar to that of VLDL + LDL cholesterol. These results indicate that dietary cholesterol and type of fat have different effects on the distribution of cholesterol among the major serum lipoproteins of the baboon.
In vitro synthesis of DNA, protein, and lipids by the de-endothelialized rabbit aorta.
Authors: Rosenfeld R S , Drouet L , Cintron J , Paul I , Won J , Spaet T H
Published: June 2011

The uptake of [3H] leucine, [3H] thymidine, [14C] acetate, and [14C] mevalonic acid by aortic intima media from normal rabbits and from rabbits subjected to a single balloon de-endothelialization as measured 6 days, 2 months, and 4 months after treatment to determine how long the injury-induced stimulation of incorporation of these precursors into tissue components persisted beyond 6 days, the time of maximum proliferative response of the smooth muscle cells. We found that [3H] thymidine incorporation (indicative of DNA synthesis and the potential for cell proliferation) was about three times greater in the de-endothelialized tissue than in the control tissue 6 days after vessel injury, but that by 2 months it was normal. Labeled leucine incorporation into the de-endothelialized tissue (a measure of protein synthesis) was eight times higher than normal at the time of maximum proliferative response to injury (6 days), and showed no decrease under identical incubation conditions in ballooned tissue obtained 2 months after de-endothelialization; it continued high at 4 months. Both [14C] acetate and [14C] mevalonate uptake into lipids by the aortic tissue were enhanced by the injury; this increased incorporation was still evident at 4 months. Thus, de-endothelialization of the aorta triggers a vessel wall response characterized by augmented protein synthesis and lipogenesis, which persists at least 4 months after injury and at least 2 months after DNA synthesis has normalized.
Secretory phenotypes of endothelial cells in culture: comparison of aortic, venous, capillary, and corneal endothelium.
Authors: Sage H , Pritzl P , Bornstein P
Published: June 2011

Endothelial cells from different tissues display variations in morphology, intercellular junctions, cell surface and growth properties, and in production of basal lamina components, both in vivo and in vitro. We have investigated the spectra of extracellular proteins secreted by bovine endothelial cells cultured from large vessels, cornea, and capillaries. Aortic, venous, and corneal endothelial cells displayed highly similar patterns of protein synthesis as judged by analysis of the culture medium; the major products were fibronectin, a glycoprotein similar or identical to platelet thrombospondin, and Type III procollagen. Ion-exchange chromatography, followed by peptide mapping, confirmed the presence of EC, a novel endothelial collagen previously described in bovine aortic endothelial cell cultures. Minor variations were found in the collagens of the cell layers: Type III, the predominant interstitial collagen, was associated with the basement membrane Types IV and V and, in the case of corneal endothelium, with Type I. In contrast, capillary endothelial cells secreted significantly more collagen than did the aortic, venous, and corneal cells. Approximately 50% of the protein in the culture medium was collagenous and consisted of Types I and III collagen in a ratio of 2:3. These interstitial collagens were the only types detected in capillary cell layers as well. The pattern and overall rate of collagen synthesis by capillary endothelial cells in vitro contrasted significantly with that of the other endothelial cell types and closely resembled that described for cultures of sprouting endothelium. These alterations in secretory phenotype may reflect: 1) a true difference in cell type between capillary and other types of endothelium, 2) differences resulting from cell isolation and initial culture conditions, or 3) a correlation between growth regulation and protein synthesis.
Lipoprotein metabolism in nonresponders to increased dietary cholesterol.
Authors: Ginsberg H , Le N A , Mays C , Gibson J , Brown W V
Published: June 2011

We have studied the effect of increased dietary cholesterol on production and degradation of plasma very low density lipoproteins and low density lipoproteins. We studied five unselected normal volunteers who were on weight-maintaining diets consisting of 45% carbohydrate, 40% fat, and 15% protein with a ratio of polyunsaturated to saturated fat of 0.4. Cholesterol content was 150 mg/1000 kcal in Period A and 500 mg/1000 kcal in Period B. Subjects were fed each diet for 4 to 5 weeks. The turnover of apoproteins B in very low density and low density lipoproteins and of triglyceride in very low density lipoproteins were measured during the last 2 weeks of each study period using 131I-labeled very low density lipoproteins and 125I-labeled low density lipoproteins and 2-3H-glycerol, respectively. There was no significant change in plasma total cholesterol or triglycerides or in low density lipoprotein cholesterol levels during the high cholesterol versus the low cholesterol diet. Similarly, high cholesterol intake had no effect on the rate of production or clearance of apo B in very low density and low density lipoproteins or of triglyceride in very low density lipoproteins. These data indicate that the flux of very low density lipoproteins does not change in nonresponders to high cholesterol diets.
Plasma lipoproteins in familial hepatic lipase deficiency.
Authors: Connelly P W , Maguire G F , Lee M , Little J A
Published: June 2011

We have studied the lipoproteins, apolipoproteins, and postheparin lipase activities in an extended pedigree with familial hepatic lipase deficiency. A deficiency of hepatic lipase was found in three of five brothers and in one of their children. Triglyceride enrichment of low density and high density lipoproteins was identified as the constitutive phenotype. beta-very low density lipoprotein was observed in hepatic lipase-deficient subjects, but it was absent when the plasma triglyceride concentration was less than 1 mM/l. The hepatic lipase-deficient subjects had normal or elevated low density lipoprotein cholesterol and high density lipoprotein cholesterol concentrations. Hyperprebetalipoproteinemia, hyperbetalipoproteinemia, and hyperalphalipoproteinemia were observed in both affected and unaffected family members. Compared with the unaffected family members, the hepatic lipase-deficient subjects had no significant differences in very low density lipoprotein cholesterol, very low density lipoprotein triglyceride, or low density lipoprotein cholesterol. These observations are consistent with the presence of additional genes causing hyperlipidemia in this family, independent of the deficiency of hepatic lipase.
Endothelial monolayer integrity. Perturbation of F-actin filaments and the dense peripheral band-vinculin network.
Authors: Wong M K , Gotlieb A I
Published: June 2011

The role of the actin microfilaments in maintaining the integrity of the monolayer and activating endothelial repair processes is not well understood. This study was designed to characterize the prominent changes in F-actin distribution in endothelial cells that are associated with shape changes in the cells after perturbation of a confluent monolayer. F-actin was localized by using rhodamine phalloidin and fluorescence microscopy. The dense peripheral band (DPB) and vinculin cell-cell junctions were co-localized by using double fluorescence and immunofluorescence microscopy. Thrombin and 12-o-tetradecanoyl-myristyl-13-acetate (TPA) caused loss of the DPB and an increase in the central microfilament bundles, while agents that caused rounding of the cells (including plasmin, trypsin, and chymotrypsin) did not cause loss of the DPB although large gaps were formed between cells. The thrombin and TPA effects were rapid and reversible and were associated with an accompanying loss of vinculin cell-cell plaques. The mechanisms of the effects were not studied. It was postulated that thrombin and TPA were activating endothelial repair processes.
Atherogenesis during low level hypercholesterolemia in the nonhuman primate. I. Fatty streak formation.
Authors: Masuda J , Ross R
Published: June 2011

Although a large body of data is available concerning atherogenesis in animals maintained at high levels of hypercholesterolemia, little data are available for animals maintained at lower levels of hypercholesterolemia for longer periods of time, closer to those observed in humans. The chronologic sequence of cellular events and interactions that occur during the formation of the lesions of atherosclerosis was investigated during relatively low level hypercholesterolemia (200 to 400 mg/dl) in a series of nonhuman primates (Macaca nemestrina). The arterial tree of each animal was examined by light microscopy and scanning and transmission electron microscopy. Immunohistochemical staining with monoclonal antibodies specific for smooth muscle cells, monocyte-macrophages, and T-lymphocytes was performed to analyze the cellular composition of the lesions. After 6 months of low level hypercholesterolemia, the surface of the aorta contained large numbers of adherent leukocytes, many of which were in the process of entering the artery. This resulted in irregularly shaped nodular elevations, or fatty streaks, preferentially located at branch sites and bifurcations. The fatty streaks consisted of intimal accumulations of numerous lipid-laden macrophages together with relatively small numbers of T-lymphocytes. With lesion progression, the thickness of the fatty streaks increased, and their surfaces became irregular and frequently showed disruptions of covering endothelial cells resulting in exposure of subendothelial macrophages. Platelet microthrombi were observed over some of the exposed macrophages at some branches or bifurcations in every animal studied. These observations made during the early phases of atherosclerosis lesion formation are virtually identical to those described in our previous reports in high level hypercholesterolemic nonhuman primates (600 to 1000 mg/dl) with the exception that the changes occurred more slowly in the lower levels of hypercholesterolemia.
Expression of elastase activity by human monocyte-macrophages is modulated by cellular cholesterol content, inflammatory mediators, and phorbol myristate acetate.
Authors: Rouis M , Nigon F , Lafuma C , Hornebeck W , Chapman M J
Published: June 2011

We investigated the effects of a number of stimulatory agents on the production of both cell-associated and extracellular elastase-type enzymes on human monocyte-macrophages in vitro and of the modulation of such effects by modification of cellular cholesterol content. The stimulatory agents included phorbol myristate acetate (PMA) and the inflammatory mediators, lipopolysaccharide (LPS), opsonized zymosan (OZ), and platelet activating factor (PAF). Using the synthetic substrate, N-succinyl-trialanyl-paranitroanilide (SANA), we detected cell-associated elastase-like activity in monocyte-derived macrophages. Such activity increased markedly with cell maturation over the period from 5 to 15 days of adherence culture. While PAF (10 micrograms/ml) and LPS (10 micrograms/ml) were without effect on cell-associated elastase-like activity in macrophages, PMA (100 ng/ml) and OZ (1 mg/ml) markedly stimulated such activity in cells cultured for 15 days. Furthermore, a fivefold increase in the cell-associated elastase-like activity of macrophages occurred upon cholesterol loading of the cells with acetylated low density lipoprotein (AcLDL). By contrast, this activity was markedly diminished upon depletion of cellular cholesterol content after incubation with high density lipoprotein (HDL3). Latent elastinolytic activity in the culture medium was detected by use of a radioactive substrate, insoluble 3H-elastin, after initial tryptic treatment of the medium. Such latent elastase activity was secreted only by activated macrophages; the relative potency of stimulation was: PMA greater than LPS = PAF greater than OZ. Increase in cellular cholesterol content alone markedly enhanced the secretion of elastase (from undetectable levels to 28 ng of 3H-elastin degraded/hr/micrograms DNA). In all cases, both the cell-associated and secreted latent elastinolytic activities were due to metalloproteases, in view of their 90% inhibition by 2 mM EDTA. Cholesterol-loaded macrophages, which displayed an approximately 40-fold increase in total cholesterol content as compared to control cells, remained sensitive to the action of activators of OZ and PMA, while LPS and PAF exerted only weak effects. Our data indicate that cellular cholesterol content and inflammatory mediators are effective stimulants of the production and secretion of elastase-type enzymes by human monocyte-macrophages. Among these factors, cellular cholesterol content, OZ, PAF, and LPS may represent factors of relevance to the inflammatory role of the macrophage in atherogenesis and more specifically to the alteration of elastin structure in the extracellular matrix of the vessel wall.
Heterogeneity of N-linked sugar chains of apolipoprotein B-100 in Watanabe heritable hyperlipidemic and fasting rabbits.
Authors: Tsunemitsu M , Ishikawa Y , Taniguchi T , Fukuzaki H
Published: June 2011

We have elucidated the structures of N-linked sugar chains of human apolipoprotein (apo) B-100 (Arch Biochem Biophys 1989; 273:197-205). To investigate the role of the carbohydrate moieties of apolipoprotein B-100, we determined the structures of the N-linked sugar chains of apo B-100 purified from low density lipoprotein (LDL) of a Watanabe heritable hyperlipidemic (WHHL) rabbit and compared them with those of fasting Japanese White rabbits. The N-linked oligosaccharides of apo B-100 were liberated by hydrozinolysis, followed by NaB3H4 reduction, and were fractionated by paper electrophoresis and Bio-Gel P-4 column chromatography. These consisted of one neutral fraction (N) and two acidic fractions (A1 and A2) in both WHHL and fasting rabbits. N contained high mannose type oligosaccharides consisting of Man5GlcNAc2 to Man9GlcNAc2. A1 and A2 contained monosialylated and disialylated biantennary complex type oligosaccharides, respectively. The molar ratios of N, A1, and A2 were 5:2:2 in the WHHL rabbit and 4:2:5 in fasting rabbits. The content of sialic acid residues in the WHHL rabbit was calculated to be 0.64 by taking the value of that in fasting rabbits as 1.0. These results show the heterogeneity of N-linked sugar chains of apo B-100 in WHHL and fasting rabbits and suggest the possibility that the characteristics of LDL in WHHL rabbits may be altered by making the surface charge more positive than in fasting rabbits.
Roles of calcium, cyclic nucleotides, and protein kinase C in regulation of endothelial permeability.
Authors: Yamada Y , Furumichi T , Furui H , Yokoi T , Ito T , Yamauchi K , Yokota M , Hayashi H , Saito H
Published: June 2011

We studied the effects of calcium, cyclic nucleotides, and protein kinase C on albumin transfer, electrical resistance, and cytoskeletal actin filaments in cultured human umbilical vein endothelial cells. The endothelial monolayer grown on collagen-treated filters markedly restricted the transfer of albumin relative to its transfer across the filter alone. Both Ca++ ionophore A23187 and ethyleneglycol tetraacetic acid disrupted the integrity of the endothelial monolayer, thereby increasing endothelial albumin transfer and decreasing electrical resistance in a concentration-dependent manner. Neither W-7, a calmodulin antagonist, nor TMB-8, an intracellular Ca++ antagonist, influenced endothelial permeability. In contrast, increases in intracellular cyclic adenosine 5'-monophosphate (AMP) and/or cyclic guanosine 5'-monophosphate (GMP) induced by dibutyryl cyclic AMP, forskolin, 3-isobutyl-1-methylxanthine, 8-bromo cyclic GMP, dibutyryl cyclic GMP, or sodium nitroprusside significantly elevated endothelial electrical resistance and inhibited albumin transfer; similar effects resulted from activation of protein kinase C by phorbol-12-myristate-13-acetate or 1-oleoyl-2-acetyl-glycerol. These substances ruffled the dense peripheral bands of F-actin without compromising the integrity of endothelial monolayer. These results suggest that calcium, cyclic nucleotides, and protein kinase C play important roles in the regulation of endothelial permeability and the maintenance of endothelial integrity.
Platelet adhesion to vascular cells. The role of exogenous von Willebrand factor in platelet adhesion.
Authors: Nievelstein P F , de Groot P G , D'Alessio P , Heijnen H F , Orlando E , Sixma J J
Published: June 2011

Platelet deposition on cultured fibroblasts and on their extracellular matrix (FBM) was investigated in a flow system with citrated blood and was compared with platelet deposition on cultured endothelial cells, smooth muscle cells, and their extracellular matrices. Platelet deposition was present at all surfaces except on intact endothelial cells. Deposition on FBM consisted of contact platelets, spread platelets, and a few small aggregates. On intact fibroblasts cells, the surface coverage was lower, and platelets formed aggregates. Factors involved in primary hemostasis, particularly the wall shear rate, von Willebrand factor (vWF), and fibronectin, were investigated on FBM. The reactivity of FBM was determined by the passage number of the cultured cells. The vWF was involved in platelet adhesion on FBM at only the high shear rate (greater than 800 s-1). Platelet deposition was independent of plasma fibronectin at all shear rates tested. Matrix-associated fibronectin was involved in adhesion at low and high wall shear rates. We conclude that FBM can be used as a platelet adhesive surface especially to study the contribution of exogenous vWF to platelet adhesion because FBM does not contain vWF.