Structure-function Studies of ApoA-I Variants: Site-directed Mutagenesis and Natural Mutations

Journal of Lipid Research. Aug, 2002  |  Pubmed ID: 12177172

Five mutants of apolipoprotein A-I (apoA-I), apoA-I(Delta63-73), apoA-I(Delta140-150), apoA-I(63-73@140-150), apoA-I(R149V), and apoA-I(P143A) were compared with human plasma apoA-I for their ability to promote cholesterol and phospholipid efflux from HepG2 cells. A significantly lower capacity to promote cholesterol and phospholipid efflux was observed with lipid-free apoA-I(Delta63-73), while mutations apoA-I(Delta140-150) and apoA-I(P143A) affected phospholipid efflux only. When added as apoA-I/palmitoyloleoyl phosphatidylcholine (POPC) complex, mutations apoA-I(63-73@140-150) and apoA-I(Delta140-150) affected cholesterol efflux. None of the mutations affected alpha-helicity of the lipid-free mutants or their self-association. Five natural mutations of apoA-I, apoA-I(A95D), apoA-I (Y100H), apoA-I(E110K), apoA-I(V156E), and apoA-I (H162Q) were studied for their ability to bind lipids and promote cholesterol efflux. None of the mutations affected lipid-binding properties, cholesterol efflux, or alpha-helicity of lipid-free mutants. Two mutations affected self-association of apoA-I: apoA-I(A95D) was more prone to self-association, while apoA-I(E100H) did not self-associate. The following conclusions could be made from the combined data: i) regions 210-243 and 63-100 are the lipid-binding sites of apoA-I and are also required for the efflux of lipids to lipid-free apoA-I, suggesting that initial lipidation of apoA-I is rate limiting in efflux; ii) in addition to the lipid-binding regions, the central region is important for cholesterol efflux to lipidated apoA-I, suggesting its possible involvement in interaction with cells.

Delineation of the Role of Pre-beta 1-HDL in Cholesterol Efflux Using Isolated Pre-beta 1-HDL

Arteriosclerosis, Thrombosis, and Vascular Biology. Sep, 2002  |  Pubmed ID: 12231570

The role of pre-beta1-high density lipoprotein (pre-beta1-HDL) in cholesterol efflux was investigated by separating human plasma into purified pre-beta1-HDL and pre-beta1-HDL-deficient plasma by using a monoclonal antibody specifically reacting with pre-beta1-HDL.

Single Session Exercise Stimulates Formation of Pre Beta 1-HDL in Leg Muscle

Journal of Lipid Research. Mar, 2003  |  Pubmed ID: 12562839

Physical activity can raise the level of circulating HDL cholesterol. Pre beta 1-HDL is thought to be either the initial acceptor of cellular cholesterol or virtually the first particle in the pathway of the formation of HDL from apolipoprotein A-I and cellular lipids. We have therefore sought to identify pre beta 1-HDL in arterial and venous circulations of exercising legs in healthy individuals and in subjects with stable Type 2 diabetes mellitus. Blood samples were taken simultaneously from the femoral artery and vein before and after 25 min cycling exercise. The major findings were, first, that exercise significantly increased plasma concentration of pre beta 1-HDL (20% increase, P < 0.05) and second, that the pre beta 1-HDL concentration was significantly higher in the venous compared with the arterial blood both before and after exercise in both diabetics and controls. In the combined population, formation of pre beta 1-HDL at rest was 9.9 +/- 5.2 mg/min and exercise enhanced pre beta 1-HDL formation 6.6-fold in both groups.

Natural Mutations of Apolipoprotein A-I Impairing Activation of Lecithin:cholesterol Acyltransferase

Biochimica Et Biophysica Acta. Feb, 2003  |  Pubmed ID: 12573451

Five natural mutations of apolipoprotein A-I (apoA-I), apoA-I(A95D), apoA-I(Y100H), apoA-I(E110K), apoA-I(V156E) and apoA-I(H162Q), were studied for their ability to activate lecithin:cholesterol acyltransferase (LCAT). Mutants apoA-I(E110K), apoA-I(V156E) and apoA-I(H162Q) had an impaired ability to activate LCAT. Combined with data on other apoA-I mutants this finding is consistent with the idea that the central region between amino acids 110 and 160 is likely to be the "active site" of apoA-I involved in the interaction with LCAT and that a specific sequence of apoA-I is required for activation of the enzyme.

Low-dose Vasopressin in the Treatment of Septic Shock in Sheep

American Journal of Respiratory and Critical Care Medicine. Aug, 2003  |  Pubmed ID: 12791578

After induction of cecal perforation, 20 anesthetized sheep were randomized to be treated, when arterial blood pressure fell below 75 mm Hg, with vasopressin (fixed dose of 0.02 U/minute), norepinephrine (0.5-5 microg/kg/minute titrated to maintain mean arterial pressure between 75 and 85 mm Hg), vasopressin + norepinephrine (vasopressin at fixed dose 0.01 U/minute plus norepinephrine titrated as for norepinephrine only group), or no vasopressor (Ringer's lactate [control]). Mean arterial pressure was well maintained in all treatment groups. Superior mesenteric arterial blood flow was significantly lower in the vasopressin + norepinephrine group than in the vasopressin group. Vasopressin alone or combined with norepinephrine limited the increase in blood lactate concentration and ileal PCO2-gap compared with control and norepinephrine groups. Urine output was higher in the vasopressin group than in control and norepinephrine groups. Survival time was longer in the vasopressin (30 +/- 6 hours) and vasopressin + norepinephrine (30 +/- 3 hours) groups than in the norepinephrine group (20 +/- 1 hours, p < 0.05) and in all treatment groups than in the control group (17 +/- 2 hours, p < 0.05). Tissue injury was less severe in the vasopressin and vasopressin + norepinephrine groups than in the others. In this clinically relevant model of septic shock due to peritonitis, vasopressin administration (alone or with norepinephrine) can prolong survival.

Expression of Caveolin-1 Enhances Cholesterol Efflux in Hepatic Cells

The Journal of Biological Chemistry. Apr, 2004  |  Pubmed ID: 14729661

HepG2 cells were stably transfected with human caveolin-1 (HepG2/cav cells). Transfection resulted in expression of caveolin-1 mRNA, a high abundance of caveolin-1 protein, and the formation of caveolae on the plasma membrane. Cholesterol efflux from HepG2/cav cells was 280 and 45% higher than that from parent HepG2 cells when human plasma and human apoA-I, respectively, were used as acceptors. The difference in efflux was eliminated by treatment of cells with progesterone. There was no difference in cholesterol efflux to cyclodextrin. Cholesterol efflux from plasma membrane vesicles was similar for the two cell types. Transfection led to a 40% increase in the amount of plasma membrane cholesterol in cholesterol-rich domains (caveolae and/or rafts) and a 67% increase in the rate of cholesterol trafficking from intracellular compartments to these domains. Cholesterol biosynthesis in HepG2/cav cells was increased by 2-fold, and cholesterol esterification was reduced by 50% compared with parent HepG2 cells. The proliferation rate of transfected cells was significantly lower than that of non-transfected cells. Transfection did not affect expression of ABCA1 or the abundance of ABCA1 protein, but decreased secretion of apoA-I. We conclude that overexpression of caveolin-1 in hepatic cells stimulates cholesterol efflux by enhancing transfer of cholesterol to cholesterol-rich domains in the plasma membrane.

Pediatric En Bloc Dual Kidney-pancreas Transplantation into an Adult Recipient: a Simplified Technique. Benefits of the En Bloc Kidney-pancreas Transplantation Technique in Pediatric Donors

American Journal of Transplantation : Official Journal of the American Society of Transplantation and the American Society of Transplant Surgeons. Apr, 2004  |  Pubmed ID: 15023161

The lower age limit for pancreas donors is not well defined. Fear of inadequate islet beta-cell mass and of technical complications has hampered the use of pediatric donors. A surgical technique of 'en bloc' kidney-pancreas is described. Both kidneys and pancreas were removed en bloc from a 13-kg, 31-month-old child. During bench preparation, one anastomosis was performed between the portal vein and the inferior vena cava. The proximal end of the aorta was closed. The bloc was transplanted into a 36-year-old type I diabetic patient intraperitoneally in the right iliac fossa. The kidneys functioned immediately. Pancreatic graft function resumed after POD 15 but insulin therapy was maintained until POD 112. Currently, the patient retains excellent kidney and pancreas graft functions. Very young donors can be accepted as pancreas donors for adult recipients, although slow recovery of pancreatic function can be expected. Use of the en bloc technique is well suited for very small children, as it prevents potential vascular complications.

Physical Fitness and Reverse Cholesterol Transport

Arteriosclerosis, Thrombosis, and Vascular Biology. Jun, 2004  |  Pubmed ID: 15072992

Physical exercise is associated with a decreased risk of cardiovascular disease, which may be partly caused by the effect of exercise on the lipoprotein profile. The most consistent effect of exercise on lipoprotein metabolism is an increase in high-density lipoprotein (HDL).

Regression of Left Ventricular Hypertrophy After Arteriovenous Fistula Closure in Renal Transplant Recipients: a Long-term Follow-up

American Journal of Transplantation : Official Journal of the American Society of Transplantation and the American Society of Transplant Surgeons. Dec, 2004  |  Pubmed ID: 15575907

The long-term effects of hemodialysis arteriovenous fistula (AVF) closure on left ventricular (LV) morphology are unknown. Using echocardiography, we prospectively studied 17 kidney transplant recipients before, 1, and, 21 months after AVF closure (mean fistula flow 1371 +/- 727 mL/min). Eight kidney transplant recipients with a patent AVF, matched for age, time after AVF creation, and time after transplantation, served as controls. LV mass index (LVMI) decreased from 139 +/- 44 g/m2 before AVF closure to 127 +/- 45 g/m2 and 117 +/- 40 g/m2 at 1 and 21 months post-closure, respectively (p < 0.001), but remained unchanged in controls. LV hypertrophy prevalence (LVMI > 125 g/m2) decreased from 65% before, to 41% early, and 18%, late, after surgery (p = 0.008), mostly from a decrease in LV end-diastolic diameter. Consequently, the prevalence of LV concentric remodeling (relative wall thickness > 0.45 without hypertrophy) increased from 12% before, to 35% early, and 65% late, after surgery (p = 0.003). Diastolic arterial blood pressure increased from 78 +/- 15 mmHg before, to 85 +/- 13 mmHg early, and 85 +/- 10 mmHg late, after surgery (p < 0.015). In conclusion, closure of large and/or symptomatic AVF induces long-term regression of LV hypertrophy. However, residual concentric remodeling geometry as well as diastolic blood pressure increase may blunt the expected beneficial cardiac effects of the procedure.

Demethylation Using the Epigenetic Modifier, 5-azacytidine, Increases the Efficiency of Transient Transfection of Macrophages

Journal of Lipid Research. Feb, 2005  |  Pubmed ID: 15520456

This study was aimed at developing a method for high-efficiency transient transfection of macrophages. Seven methods were evaluated for transient transfection of murine macrophage RAW 264.7 cells. The highest transfection efficiency was achieved with DEAE-dextran, although the proportion of cells expressing the reporter gene did not exceed 20%. It was subsequently found that the cytomegalovirus plasmid promoter in these cells becomes methylated. When cells were treated with the methylation inhibitor 5-azacytidine, methylation of the plasmid promoter was abolished and a dose-dependent stimulation of reporter gene expression was observed with expression achieved in more than 80% of cells. Treatment of cells with 5-azacytidine also caused increased efficiency of transfection of macrophages with plasmids driven by RSV, SV40, and EF-1alpha promoters and transient transfection of human HepG2 cells. Inhibition of methylation also increased the amount and activity of sterol 27-hydroxylase (CYP27A1) detected in RAW 264.7 cells transfected with a CYP27A1 expression plasmid. Treatment of cells with 5-azacytidine alone did not affect either cholesterol efflux from nontransfected cells or expression of ABCA1 and CYP27A1. However, transfection with CYP27A1 led to a 2- to 4-fold increase of cholesterol efflux. We conclude that treatment with 5-azacytidine can be used for high-efficiency transient transfection of macrophages.

Elevated HDL Cholesterol is Functionally Ineffective in Cardiac Transplant Recipients: Evidence for Impaired Reverse Cholesterol Transport

Transplantation. Feb, 2006  |  Pubmed ID: 16477221

Cardiac transplant recipients frequently have high plasma HDL levels but it is unclear whether these promote a cardioprotective profile.

Unique Secondary Chromosomal Abnormalities Are Frequently Found in the Chronic Phase of Chronic Myeloid Leukemia in Southern Vietnam

Cancer Genetics and Cytogenetics. Jul, 2006  |  Pubmed ID: 16772122

During the Vietnam War, southern Vietnam was exposed to a large amount of dioxin, a strong human carcinogen. Although we have observed much shorter survival in southern Vietnamese chronic myeloid leukemia (CML) patients, the cause remains to be clarified. Here, we report cytogenetic and molecular findings for 47 CML patients. Cytogenetically, the Philadelphia (Ph) chromosome was found in 44 patients (93.6%); of the remaining 3 patients with Ph-negative CML, 2 exhibited BCR/ABL transcripts but no BCR/ABL FISH fusion signals, suggesting the existence of two clones, with and without the BCR/ABL fusion gene. Surprisingly, in 17 patients (36.2%) (4 at diagnosis, 11 during chronic phase, and 2 in accelerated phase), we found several unique secondary chromosome abnormalities including trisomy 13, partial trisomy 13, and abnormalities of 1p, 3p, 6p, 7p, 10p, and 11p, which are different from the so-called additional chromosome abnormalities (extra Ph, +8, i(17q), +19, and +21) observed in blastic phase CML. FISH analysis revealed the Ph translocation with der(9) deletion in 11 patients (23.4%). Of these, 2 had two clones, with and without der(9) deletion, suggesting that der(9) deletion would occur in a subset of patients during disease progression. These observations point to preexisting genetic instability that induces various secondary chromosome abnormalities and multiple clones, resulting in shorter survival.

Laparoscopic Live Donor Right Nephrectomy: a New Technique to Maximize the Length of the Renal Vein Using a Modified Endo GIA Stapler

European Urology. May, 2007  |  Pubmed ID: 17197070

To report the utilization of a modified Endo GIA vascular stapler to obtain the full length of the renal vein during transperitoneal laparoscopic live donor right nephrectomy.

ABCA1 Expression in Humans is Associated with Physical Activity and Alcohol Consumption

Atherosclerosis. Mar, 2008  |  Pubmed ID: 17481640

Genetic variation in ABCA1 significantly affects HDL levels and atherosclerotic risk. The aim of this study was to examine lifestyle factors influencing ABCA1 expression in human leukocytes and skeletal muscle. A fasting venous blood sample and a vastus lateralis muscle biopsy were taken from 30 volunteers (53+/-1 years; mean+/-S.E.M.). Levels of ABCA1 mRNA were measured in blood leukocytes and muscle biopsies. Plasma-induced cholesterol efflux from THP-1 human macrophages as well as plasma lipids and lipid-related parameters were also measured. The amount of alcohol consumed per week correlated strongly with both muscle ABCA1 expression (r(2)=+0.37, p<0.001) and cholesterol efflux (r(2)=+0.41, p<0.001). Higher levels of physical exercise were associated with higher leukocyte ABCA1 expression (p<0.005), and higher concentrations of plasma apoA-I (p<0.05) and pre beta(1)-HDL (p<0.001). All these relationships were independent of diabetic status on multivariate analysis. ABCA1 expression in leukocytes and skeletal muscle was not related, suggesting different regulatory mechanisms. In conclusion, ABCA1 expression in human leukocytes and muscle is associated with physical activity and alcohol consumption, respectively.

Indices of Reverse Cholesterol Transport in Subjects with Metabolic Syndrome After Treatment with Rosuvastatin

Atherosclerosis. Apr, 2008  |  Pubmed ID: 17709109

The effects of the statin, rosuvastatin on indices of reverse cholesterol transport were studied in a randomized, placebo-controlled, cross-over trial in 25 overweight subjects with defined metabolic syndrome.

Dose-dependent Regulation of High-density Lipoprotein Metabolism with Rosuvastatin in the Metabolic Syndrome

The Journal of Clinical Endocrinology and Metabolism. Feb, 2008  |  Pubmed ID: 18029469

Low plasma concentration of high-density lipoprotein (HDL) cholesterol is a risk factor for cardiovascular disease and a feature of the metabolic syndrome. Rosuvastatin has been shown to increase HDL cholesterol concentration, but the mechanisms remain unclear.

HLA Mismatches Remain Risk Factors for Acute Kidney Allograft Rejection in Patients Receiving Quadruple Immunosuppression with Anti-interleukin-2 Receptor Antibodies

Transplantation. Feb, 2008  |  Pubmed ID: 18322434

New immunosuppressive drugs such as anti-interleukin-2 receptor antibodies (aIL2R) and mycophenolate mofetil (MMF) have reduced the incidence of acute rejection after renal transplantation. Whether matching donor and recipient human leukocyte antigen (HLA) antigens is still relevant in patients receiving modern immunosuppression has been questioned.

Economic Reform in Vietnam

Culture, Health & Sexuality. Jun, 2008  |  Pubmed ID: 18446556

High-density Lipoprotein Reduces the Human Monocyte Inflammatory Response

Arteriosclerosis, Thrombosis, and Vascular Biology. Nov, 2008  |  Pubmed ID: 18617650

Whereas the anti-inflammatory effects of high-density lipoprotein (HDL) on endothelial cells are well described, such effects on monocytes are less studied.

Inhibition of Mxi1 Suppresses HIF-2alpha-dependent Renal Cancer Tumorigenesis

Cancer Biology & Therapy. Oct, 2008  |  Pubmed ID: 19018165

In clear cell renal cancers, the primary molecular defect is inactivation of the von Hippel-Lindau (VHL) gene. Loss of pVHL, the VHL gene product, leads to constitutive activation of hypoxia-inducible factor (HIF) signaling. While downregulation of HIF suppresses tumor formation by pVHL-defective renal carcinoma cells, the relative contribution of individual HIF regulated genes to HIF-dependent tumorigenesis remains under investigation. Mxi1, a c-Myc antagonist, is a HIF target gene that inhibits mitochondrial biogenesis, reprograms cellular energy metabolism, and protects cells from c-Myc-dependent apoptosis in vitro. In the present study we show that Mxi1 is overexpressed in primary human clear cell kidney cancers. Inhibition of Mxi1 in pVHL-defective kidney cancer cells using shRNA alters their cell cycle parameters, inhibits their ability to invade matrigel, and suppresses their ability to form tumors in vivo. Compared to Mxi1-proficient tumors, Mxi1-deficient tumors display reduced cellular proliferation. These results establish Mxi1 as an important downstream target of HIF that contributes to pVHL-deficient renal cancer tumorigenesis.

Phylogenetic Analyses of Prorocentrum Spp. and Alexandrium Spp. Isolated from Northern Coast of Vietnam Based on 18S RDNA Sequence

Journal of Environmental Biology / Academy of Environmental Biology, India. Jul, 2008  |  Pubmed ID: 19195393

Some species of marine dinoflagellates belonging to genera Alexandrium and Prorocentrum have been responsible for paralytic shellfish poisoning (PSP) and diarrheic shellfish poisoning (DSP), respectively Morphological and molecular studies of 4 species including Alexandrium sp. 5, Alexandrium sp. 16, Prorocentrum sp. 1 and Prorocentrum sp. 3 that were collected in Northern coast of Vietnam were presented for the first time. By morphologic observations, we identifiedAlexandrium sp. 5 and Alexandrium sp. 16 as Alexandrium minutum, Alexandrium affine, respectively; Prorocentrum sp. 1 and Prorocentrum sp. 3 as Prorocentrum mexicanum. Sequence data from the partial 18S riboxomal RNA genes have been used to generate a phylogenetic framework with database of GenBank. The obtained results of phylogenetic analyses of species of Prorocentrum spp. and Alexandrium spp. based on 18S rDNA sequences are similar to morphological observations. Thus, molecular tool would be helpful for the identification of dinoflagellate species and further taxonomic studies in Vietnam.

Reconstituted High-density Lipoprotein Increases Plasma High-density Lipoprotein Anti-inflammatory Properties and Cholesterol Efflux Capacity in Patients with Type 2 Diabetes

Journal of the American College of Cardiology. Mar, 2009  |  Pubmed ID: 19281927

Our aim was to investigate the effects of reconstituted high-density lipoprotein (rHDL) infusions on plasma high-density lipoprotein (HDL) anti-inflammatory properties and ex vivo cholesterol efflux in patients with type 2 diabetes.

Crystallization of Synthetic Haemozoin (beta-haematin) Nucleated at the Surface of Lipid Particles

Dalton Transactions (Cambridge, England : 2003). Feb, 2010  |  Pubmed ID: 20104349

The mechanism of formation of haemozoin, a detoxification by-product of several blood-feeding organisms including malaria parasites, has been a subject of debate; however, recent studies suggest that neutral lipids may serve as a catalyst. In this study, a model system consisting of an emulsion of neutral lipid particles was employed to investigate the formation of beta-haematin, the synthetic counterpart of haemozoin, at the lipid-water interface. A solution of monoglyceride, either monostearoylglycerol (MSG) or monopalmitoylglycerol (MPG), dissolved in acetone and methanol was introduced to an aqueous surface. Fluorescence, confocal and transmission electron microscopic (TEM) imaging and dynamic light scattering analysis of samples obtained from beneath the surface confirmed the presence of homogeneous lipid particles existing in two major populations: one in the low micrometre size range and the other in the hundred nanometre range. The introduction of haem (Fe(iii)PPIX) to this lipid particle system under biomimetic conditions (37 degrees C, pH 4.8) produced beta-haematin with apparent first-order kinetics and an average half life of 0.5 min. TEM of monoglycerides (MSG or MPG) extruded through a 200 nm filter with haem produced beta-haematin crystals aligned and parallel to the lipid-water interface. These TEM data, together with a model system replacing the lipid with an aqueous organic solvent interface using either methyl laurate or docosane demonstrated that the OH and C[double bond, length as m-dash]O groups are apparently necessary for efficient nucleation. This suggests that beta-haematin crystallizes via epitaxial nucleation at the lipid-water interface through interaction of Fe(iii)PPIX with the polar head group. Once nucleated, the crystal grows parallel to the interface until growth is terminated by the curvature of the lipid particle. The hydrophobic nature of the mature crystal favours an interior transport resulting in crystals aligned parallel to the lipid-water interface and each other, strikingly similar to that seen in malaria parasites.

Sexuality and Health in Vietnam--new Directions. Introduction

Culture, Health & Sexuality. Aug, 2010  |  Pubmed ID: 20544445

Inhibitors of Osteoclastogenesis from Lawsonia Inermis Leaves

Bioorganic & Medicinal Chemistry Letters. Aug, 2010  |  Pubmed ID: 20634065

Ten phenolic compounds (1-10) were isolated from a methanol extract of Lawsonia inermis leaves including two new ones, lawsoniasides A (1) and B (2). Their structures were elucidated by spectroscopic methods (NMR and FTICRMS) in combination with acid hydrolysis and GC analyses. Compounds 4 and 5 showed a significant inhibition on receptor activator for nuclear factor-kappaB ligand-induced osteoclast formation in murine bone-marrow macrophages.

Increase on the Initial Soluble Heme Levels in Acidic Conditions is an Important Mechanism for Spontaneous Heme Crystallization in Vitro

PloS One. 2010  |  Pubmed ID: 20856937

Hemozoin (Hz) is a heme crystal that represents a vital pathway for heme disposal in several blood-feeding organisms. Recent evidence demonstrated that β-hematin (βH) (the synthetic counterpart of Hz) formation occurs under physiological conditions near synthetic or biological hydrophilic-hydrophobic interfaces. This seems to require a heme dimer acting as a precursor of Hz crystals that would be formed spontaneously in the absence of the competing water molecules bound to the heme iron. Here, we aimed to investigate the role of medium polarity on spontaneous βH formation in vitro.

The Neutral Lipid Composition Present in the Digestive Vacuole of Plasmodium Falciparum Concentrates Heme and Mediates β-hematin Formation with an Unusually Low Activation Energy

Biochemistry. Nov, 2010  |  Pubmed ID: 20979358

In eukaryotic cells, neutral lipids serve as major energy storage molecules; however, in Plasmodium falciparum, a parasite responsible for causing malaria in humans, neutral lipids may have other functions during the intraerythrocytic stage of the parasite life cycle. Specifically, experimental data suggest that neutral lipid structures behave as a catalyst for the crystallization of hemozoin, a detoxification byproduct of several blood-feeding organisms, including malaria parasites. Synthetic neutral lipid droplets (SNLDs) were produced by depositing a lipid blend solution comprised of mono- and diglycerides onto an aqueous surface. These lipid droplets are able to mediate the production of brown pigments that are morphologically and chemically identical to hemozoin. The partitioning of heme into these SNLDs was examined by employing Nile Red, a lipid specific dye. Soluble ferriprotoporphyrin IX was observed to spontaneously localize to the lipid droplets, partitioning in a pH-dependent manner with an estimated log P of 2.6. Interestingly, the pH profile of heme partitioning closely resembles that of β-hematin formation. Differential scanning calorimetry and kinetic studies demonstrated that the SNLDs provide a unique environment that promotes hemozoin formation. SNLD-mediated formation of the malaria pigment displayed an activation energy barrier lower than those of individual lipid components. In particular, lipid droplets composed of diglycerides displayed activation barriers lower than those composed of monoglycerides. This difference was attributed to the greater fluidity of these lipids. In conjunction with the known pattern of lipid body proliferation, it is suggested that neutral lipid structures within the digestive vacuole not only are the location of in vivo hemozoin formation but are also essential for the survival of the parasite by functioning as a kinetically competent and site specific mediator for heme detoxification.

Qualitative Study of an Operations Research Project to Engage Abused Women, Health Providers, and Communities in Responding to Gender-based Violence in Vietnam

Violence Against Women. Nov, 2011  |  Pubmed ID: 22240404

This article describes an action research project designed to engage women, health providers, and communities to respond to gender-based violence (GBV) in Vietnam. Based on results from in-depth interviews and group discussions, it considers the extent to which the project approaches were empowering for abused women. The results underscore the problems entailed in introducing systematic screening for gender-based violence into government health facilities in the low-resource setting of Vietnam, the importance of combining ideational change and rights components with support for abused women, and the difficulty of engaging male perpetrators.

Inhibitory Activity of Plantago Major L. on Angiotensin I-converting Enzyme

Archives of Pharmacal Research. Mar, 2011  |  Pubmed ID: 21547673

Eight compounds were isolated from methanol extract of Plantago major L. leaves and investigated for their ability to inhibit angiotensin I-converting enzyme activity. Among them, compound 1 showed the most potent inhibition with rate of 28.06 ± 0.21% at a concentration of 100 μM. Compounds 2 and 8 exhibited weak activities. These results suggest that compound 1 might contribute to the ability of P. major to inhibit the activity of angiotensin I- converting enzyme.

Persistent, Biologically Meaningful Prostate Cancer After 1 Year of Androgen Ablation and Docetaxel Treatment

Journal of Clinical Oncology : Official Journal of the American Society of Clinical Oncology. Jun, 2011  |  Pubmed ID: 21606419

Clinicians are increasingly willing to treat prostate cancer within the primary site in the presence of regional lymph node or even limited distant metastases. However, no formal study on the merits of this approach has been reported. We used a preoperative clinical discovery platform to prioritize pathways for assessment as therapeutic targets and to test the hypothesis that the primary site harbors potentially lethal tumors after aggressive treatment.

Expression of Hedgehog Pathway Components in Prostate Carcinoma Microenvironment: Shifting the Balance Towards Autocrine Signalling

Histopathology. Jun, 2011  |  Pubmed ID: 21707705

The hedgehog (Hh) signalling pathway has been implicated in the pathogenesis and aggressiveness of prostate cancer through epithelial-mesenchymal interactions. The aim of this study was to elucidate the cell-type partitioned expression of the Hh pathway biomarkers in the non-neoplastic and tumour microenvironments and to correlate it with the grade and stage of prostate cancer.

Chemical Constituents of the Rhizomes of Hedychium Coronarium and Their Inhibitory Effect on the Pro-inflammatory Cytokines Production LPS-stimulated in Bone Marrow-derived Dendritic Cells

Bioorganic & Medicinal Chemistry Letters. Dec, 2011  |  Pubmed ID: 22071304

The rhizomes of Hedychium coronarium have been used for the treatment of inflammation, skin diseases, headache, and sharp pain due to rheumatism in traditional medicine. From this plant, three new labdane-type diterpenes 1-3, named coronarins G-I as well as seven known 4-10, coronarin D, coronarin D methyl ether, hedyforrestin C, (E)-nerolidol, β-sitosterol, daucosterol, and stigmasterol were isolated. Their chemical structures were elucidated by mass, 1D- and 2D-nuclear magnetic resonance spectroscopy. They were evaluated for inhibitory effects on lipopolysaccharide-stimulated production of pro-inflammatory cytokines in bone marrow-derived dendritic cells. Among of them, compounds 1, 2, and 6 were significant inhibitors of LPS-stimulated TNF-α, IL-6, and IL-12 p40 productions with IC(50) ranging from 0.19±0.11 to 10.38±2.34 μM. The remains of compounds showed inactivity or due to cytotoxicity. These results warrant further studies concerning the potential anti-inflammatory benefits of labdane-type diterpenes from H. coronarium.

Ineligibility for Renal Transplantation: Prevalence, Causes and Survival in a Consecutive Cohort of 445 Patients

Clinical Transplantation. Jul, 2011  |  Pubmed ID: 20718825

Little is known about the proportion of renal transplant candidates who are considered ineligible by the transplant center, the reasons of their ineligibility and their survival during dialysis. In this retrospective, single-center study of 445 adult patients referred between 2001 and 2006, 36 (8%) were deemed ineligible for medical contraindications. The leading reason was cardiovascular (CV) (75%), specifically aorto-iliac, and/or limb vessels atheromatosis or calcifications; ischemic heart disease; or a combination thereof. Nine patients had other contraindications that were absolute for three of them; six patients displayed a combination of relative contraindications. When compared to eligible patients (N = 409), those ineligible were significantly older (60 yr vs. 48), more often diabetics (50% vs. 15%), obese (39% vs. 17%) suffering from coronary artery disease (53% vs. 11%) and peripheral arterial disease (86% vs. 11%). Their primary nephropathy was more often diabetic and/or hypertensive/nephroangiosclerosis (61% vs. 23%), and their median dialysis vintage prior to evaluation was longer (29 months vs. 10, p < 0.0001). The actuarial survival of ineligible patients was significantly lower than that of eligible patients (at five yr: 53% vs. 88%). Adequate control of CV risk factors before dialysis and early referral for transplantation might help to improve eligibility of renal transplant candidates.

Modeling a Lethal Prostate Cancer Variant with Small-cell Carcinoma Features

Clinical Cancer Research : an Official Journal of the American Association for Cancer Research. Feb, 2012  |  Pubmed ID: 22156612

Small-cell prostate carcinoma (SCPC) morphology predicts for a distinct clinical behavior, resistance to androgen ablation, and frequent but short responses to chemotherapy. We sought to develop model systems that reflect human SCPC and can improve our understanding of its biology.

Effects of Abiraterone Acetate on Androgen Signaling in Castrate-resistant Prostate Cancer in Bone

Journal of Clinical Oncology : Official Journal of the American Society of Clinical Oncology. Feb, 2012  |  Pubmed ID: 22184395

PURPOSE Persistent androgen signaling is implicated in castrate-resistant prostate cancer (CRPC) progression. This study aimed to evaluate androgen signaling in bone marrow-infiltrating cancer and testosterone in blood and bone marrow and to correlate with clinical observations. PATIENTS AND METHODS This was an open-label, observational study of 57 patients with bone-metastatic CRPC who underwent transiliac bone marrow biopsy between October 2007 and March 2010. Patients received oral abiraterone acetate (1 g) once daily and prednisone (5 mg) twice daily. Androgen receptor (AR) and CYP17 expression were assessed by immunohistochemistry, testosterone concentration by mass spectrometry, AR copy number by polymerase chain reaction, and TMPRSS2-ERG status by fluorescent in situ hybridization in available tissues. Results Median overall survival was 555 days (95% CI, 440 to 965+ days). Maximal prostate-specific antigen decline ≥ 50% occurred in 28 (50%) of 56 patients. Homogeneous, intense nuclear expression of AR, combined with ≥ 10% CYP17 tumor expression, was correlated with longer time to treatment discontinuation (> 4 months) in 25 patients with tumor-infiltrated bone marrow samples. Pretreatment CYP17 tumor expression ≥ 10% was correlated with increased bone marrow aspirate testosterone. Blood and bone marrow aspirate testosterone concentrations declined to less than picograms-per-milliliter levels and remained suppressed at progression. CONCLUSION The observed pretreatment androgen-signaling signature is consistent with persistent androgen signaling in CRPC bone metastases. This is the first evidence that abiraterone acetate achieves sustained suppression of testosterone in both blood and bone marrow aspirate to less than picograms-per-milliliter levels. Potential admixture of blood with bone marrow aspirate limits our ability to determine the origin of measured testosterone.

Labdane-Type Diterpenoids from the Rhizomes of Hedychium Coronarium Inhibit Lipopolysaccharide-Stimulated Production of Pro-inflammatory Cytokines in Bone Marrow-Derived Dendritic Cells

Chemical & Pharmaceutical Bulletin. 2012  |  Pubmed ID: 22293485

The rhizomes of Hedychium coronarium have been used for the treatment of inflammation, skin diseases, headache, and sharp pain due to rheumatism in traditional medicine. From this plant, two new labdanes, 15-methoxylabda-8(17),11E,13-trien-16,15-olide (1) and 16-methoxylabda-8(17),11E,13-trien-15,16-olide (3), named hedycoronens A and B, as well as four known, labda-8(17),11,13-trien-16,15-olide (2), 16-hydroxylabda-8(17),11,13-trien-15,16-olide (4), coronarin A (5), and corronarin E (6) were isolated. Their chemical structures were elucidated by mass, 1D- and 2D-nuclear magnetic resonance (NMR) spectroscopy. They were evaluated for inhibitory effects on the lipopolysaccharide (LPS)-stimulated production of pro-inflammatory cytokines in bone marrow-derived dendritic cells. Among of them, compounds 1-3 were potent inhibitors of LPS-stimulated interleukin-6 (IL-6) and IL-12 p40, with IC(50) ranging from 4.1±0.2 to 9.1±0.3 μM. Compounds 1 and 3 showed moderate inhibitory activity on the tumor necrosis factor-α (TNF-α) production with IC(50) values of 46.0±1.3 and 12.7±0.3 μM. The remains of compounds showed inactivity. These results warrant further studies concerning the potential anti-inflammatory benefits of labdane-diterpenes from H. coronarium.

Human Granulocytic Anaplasmosis in Eastern France: Clinical Presentation and Laboratory Diagnosis

Diagnostic Microbiology and Infectious Disease. Mar, 2012  |  Pubmed ID: 22321996

Human granulocytic anaplasmosis (HGA) is a tick-borne infection characterised by an acute, nonspecific febrile illness. To date, few clinical cases have been supported by both a positive polymerase chain reaction (PCR) assay and subsequent seroconversion against Anaplasma phagocytophilum antigen all over Europe. We report here 3 consecutive cases of HGA that occurred during the summer of 2009 which fulfilled the epidemiologic, clinical, and biological criteria for HGA. These data highlight PCR assay on ethylenediaminetetraacetic acid blood rather than serology as the diagnostic test of choice during the acute phase of the disease. In endemic areas, HGA should be investigated in patients presenting an undifferentiated febrile illness with cytopenia, elevated rates of liver enzymes, and increased C-reactive protein values.

Mechanism of Cholesterol Efflux in Humans After Infusion of Reconstituted High-density Lipoprotein

European Heart Journal. Mar, 2012  |  Pubmed ID: 21498847

Objectives Infusion of reconstituted HDL (rHDL) leads to changes in HDL metabolism as well as to an increased capacity of plasma to support cholesterol efflux providing an opportunity to investigate mechanisms linking cholesterol efflux to changes in plasma HDL. Methods and results Patient plasmas after infusion of rHDL were tested ex vivo for their capacity to stimulate cholesterol efflux. Reconstituted HDL enhanced mobilization of cholesterol from tissues in vivo as shown by rising HDL cholesterol concentrations over the infusion period. Infusion of rHDL in vivo led to increased cholesterol efflux ex vivo; surprisingly, removing apoB-containing lipoproteins while preserving all HDL subfractions eliminated this increase. Infusion of rHDL led to the remodelling of plasma HDL; however, the capacity of plasma to support cholesterol efflux did not correlate with changes in the concentrations of any of HDL subfractions. Unmodified rHDL accounted for only a proportion of the increment in cholesterol efflux capacity. Furthermore, studies using HeLa and BHK cells overexpressing ABCA1, ABCG1, and SR-B1 showed that the contribution of these cellular mediators of cholesterol efflux to the enhanced capacity of plasma for the efflux was minimal. Conclusion Enhanced cholesterol efflux from tissues requires the presence of apoB-containing lipoproteins and may involve enhanced flow of cholesterol through multiple components of the reverse cholesterol transport pathway rather than being determined by a specific HDL subfraction.