Distribution of natural radionuclides in NORM samples from North Abu Rusheid area, Egypt.

The North Abu Rusheid area in Egypt is a well-known high background natural radiation area (HBNRA) due to the existence of naturally occurring radioactive materials (NORMs) in mylonitic rocks. In this study, 27 rock samples were selected for dose estimation studies. 238U and 232Th were measured using inductively coupled plasma mass spectrometry (ICP-MS) and 40K was measured using sodium iodide (thallium) gamma-ray spectroscopy. The ranges of activity concentrations (Bq/kg) of 238U, 232Th and 40K in the samples varied from 270 ± 2 to 2120 ± 29, 350 ± 2 to 1840 ± 27 and 20 ± 2 to 1390 ± 35 with mean values of 980 ± 349, 770 ± 351, and 640 ± 402 Bq/kg, respectively. The radiological hazard parameters were estimated from activity concentrations of 238U, 232Th and 40K and compared to United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) values. The present study revealed that the hazard parameters were several times higher than the worldwide averages. The U/Th concentration ratio ranged from 0.7 to 3 and could be attributed to the presence of kasolite, uranothorite, zircon, and columbite in mylonitic rocks. From the radiological protection viewpoint, it is necessary to monitor natural radionuclides in these rocks prior to their use in residential and commercial construction materials.

A high-quality genome sequence of Rosa chinensis to elucidate ornamental traits.

Rose is the world's most important ornamental plant, with economic, cultural and symbolic value. Roses are cultivated worldwide and sold as garden roses, cut flowers and potted plants. Roses are outbred and can have various ploidy levels. Our objectives were to develop a high-quality reference genome sequence for the genus Rosa by sequencing a doubled haploid, combining long and short reads, and anchoring to a high-density genetic map, and to study the genome structure and genetic basis of major ornamental traits. We produced a doubled haploid rose line ('HapOB') from Rosa chinensis 'Old Blush' and generated a rose genome assembly anchored to seven pseudo-chromosomes (512 Mb with N50 of 3.4 Mb and 564 contigs). The length of 512 Mb represents 90.1-96.1% of the estimated haploid genome size of rose. Of the assembly, 95% is contained in only 196 contigs. The anchoring was validated using high-density diploid and tetraploid genetic maps. We delineated hallmark chromosomal features, including the pericentromeric regions, through annotation of transposable element families and positioned centromeric repeats using fluorescent in situ hybridization. The rose genome displays extensive synteny with the Fragaria vesca genome, and we delineated only two major rearrangements. Genetic diversity was analysed using resequencing data of seven diploid and one tetraploid Rosa species selected from various sections of the genus. Combining genetic and genomic approaches, we identified potential genetic regulators of key ornamental traits, including prickle density and the number of flower petals. A rose APETALA2/TOE homologue is proposed to be the major regulator of petal number in rose. This reference sequence is an important resource for studying polyploidization, meiosis and developmental processes, as we demonstrated for flower and prickle development. It will also accelerate breeding through the development of molecular markers linked to traits, the identification of the genes underlying them and the exploitation of synteny across Rosaceae.

Successful fibrinolytic treatment of prosthetic heart valve thrombosis using streptokinase.

OBJECTIVES: This study aims to evaluate the clinical outcome of fibrinolytic treatment of prosthetic valve thrombosis (PVT) with 'streptokinase' as a first line treatment for these cases. METHODS: The study group was 20 consecutive patients (10 females) diagnosed with PVT. The protocol for streptokinase administration was either accelerated (intravenous infusion of 0.5 million IU over 30 minutes followed by 0.15 million IU/h) or conventional (intravenous infusion of 0.25 million IU over 30 minutes followed by 0.15 million IU/h). Success of fibrinolytic therapy was defined as complete restoration of valve function in the presence or absence of complications. RESULTS: Eighteen patients (90%) had mitral PVT and two (10%) had aortic PVT. Thrombolytic therapy with streptokinase was successful in all but one case, with a total mortality of four cases (20%). In PVT episodes, before streptokinase therapy, the prosthetic valve areas (in all cases, mitral and aortic positions) were 0.82 ± 0.21, 0.83 ± 0.21, and 0.73 ± 0.18 cm²; and the peak and mean transvalvular gradients were 38.7 ± 16.7 and 25.4 ± 8.7, 34.1 ± 8.8 and 23.2 ± 5.4, and 80.0 ± 14.1 and 45.0 ± 7.1 mmHg, respectively. After streptokinase therapy, the prosthetic valve area and peak and mean transvalvular gradients improved significantly (for all cases, mitral and aortic positions: valve area 2.17 ± 0.58, 2.21 ± 0.61, and 1.85 ± 0.07 cm², peak gradient 18.7 ± 11.0, 16.4 ± 7.7, and 39.0 ± 18.4, and mean gradient 9.6 ± 7.1, 8.2 ± 5.3, and 22.0 ± 11.3 mmHg, respectively; paired t-test, P<0.001 for pre- versus post-streptokinase infusion for all variables). CONCLUSION: Fibrinolytic therapy using streptokinase was an effective therapeutic strategy for the management of PVT and is a reasonable alternative to surgery.

Ultrastructural and molecular changes in the developing small intestine of the toad Bufo regularis.

The ontogenetic development of the small intestine of the toad Bufo regularis was investigated using twofold approaches, namely, ultrastructural and molecular. The former has been done using transmission electron microscope and utilizing the developmental stages 42, 50, 55, 60, 63, and 66. The most prominent ultrastructural changes were recorded at stage 60 and were more evident at stage 63. These included the appearance of apoptotic bodies/nuclei within the larval epithelium, the presence of macrophages, swollen mitochondria, distorted rough endoplasmic reticulum, chromatin condensation, and irregular nuclear envelop, and the presence of large vacuoles and lysosomes. The molecular investigation involved examining DNA content and fragmentation. The results showed that the DNA content decreased significantly during the metamorphic stages 60 and 63 compared with both larval (50 and 55) and postmetamorphic (66) stages. The metamorphic stages (60 and 63) displayed extensive DNA laddering compared with stages 50, 55, and 66. The percentage of DNA damage was 0.00%, 12.91%, 57.26%, 45.48%, and 4.43% for the developmental stages 50, 55, 60, 63, and 66, respectively. In conclusion, the recorded remodeling of the small intestine represents a model for clarifying the mechanism whereby cell death and proliferation are controlled.

Detection of bleeding disorders in Lebanon: outcomes of a pilot programme.

To promote management and awareness of bleeding disorders in Lebanon, a pilot programme was launched in 2009 by the Lebanese Hemophilia Association assisted by World Federation of Hemophilia. The aim of this study was to diagnose patients with bleeding disorders and to assess the potential challenges in implementing a screening programme. The pilot project was launched in 26 social health centres in the Bekaa valley. The study tools included the evaluation of the Tossetto Bleeding Score and the Pictorial Bleeding Assessment Chart (PBAC) for menstruation. Persons with a bleeding score higher than 2 and PBAC higher than 185 were eligible for further blood tests including the prothrombin time, partial thromboplastin time, complete blood count, bleeding time and von Willebrand ristocetin cofactor activity. 643 patients were enrolled, of whom 60.6% were women. Overall, 91 persons had an abnormal score. 50 eligible patients were tested: 32 had normal tests, nine new patients with severe Von Willebrand were discovered, 4 had VW:RiCo of 40, 3 prolonged APTT and 2 thrombocytopaenia. There was a clear correlation between the severity of the score and the willingness to perform the tests (P = 0.02). Women were reluctant to participate fully when investigators were men. The probability of adherence to the screening protocol is significantly increased when directed by women health care professional. For patients with milder forms, global screening programmes were neither feasible nor acceptable but those more severely affected have to be identified. Providers are crucial in preselecting patients with blood problems who are not coping well.

Prevalence and determinants of human papillomavirus infection and cervical lesions in HIV-positive women in Kenya.

BACKGROUND: We assessed the association of human papillomavirus (HPV) infection and cervical intraepithelial neoplasia (CIN) with various characteristics, CD4 count and use of combination antiretroviral therapy (cART) among HIV-positive women. METHODS: Cross-sectional study of 498 HIV-positive women who underwent HPV PCR-based testing, cytology, and systematic cervical biopsy. RESULTS: In all, 68.7% of women were HPV-positive, 52.6% had high-risk (hr) HPV, and 40.2% multiple type infections. High-risk human papillomavirus-positivity did not vary significantly by age but it was negatively associated with education level. The most frequent types in 113 CIN2/3 were HPV16 (26.5%), HPV35 (19.5%), and HPV58 (12.4%). CD4 count was negatively associated with prevalence of hrHPV (P<0.001) and CIN2/3 among non-users of cART (P=0.013). Combination antiretroviral therapies users (≥2 year) had lower hrHPV prevalence (prevalence ratio (PR) vs non-users=0.77, 95% confidence interval (CI): 0.61-0.96) and multiple infections (PR=0.68, 95% CI: 0.53-0.88), but not fewer CIN2/3. The positive predictive value of hrHPV-positivity for CIN2/3 increased from 28.9% at age <35 years to 53.3% in ≥45 years. CONCLUSION: The burden of hrHPV and CIN2/3 was high and it was related to immunosuppression level. Combination antiretroviral therapies ( ≥2 year) use had a favourable effect on hrHPV prevalence but cART in our population may have been started too late to prevent CIN2/3.

Insights into Populus XIP aquaporins: evolutionary expansion, protein functionality, and environmental regulation.

A novel category of major intrinsic proteins which share weak similarities with previously identified aquaporin subfamilies was recently identified in land plants, and named X (for unrecognized) intrinsic proteins (XIPs). Because XIPs are still ranked as uncharacterized proteins, their further molecular characterization is required. Herein, a systematic fine-scale analysis of XIP sequences found in flowering plant databases revealed that XIPs are found in at least five groups. The phylogenetic relationship of these five groups with the phylogenetic organization of angiosperms revealed an original pattern of evolution for the XIP subfamily through distinct angiosperm taxon-specific clades. Of all flowering plant having XIPs, the genus Populus encompasses the broadest panel and the highest polymorphism of XIP isoforms, with nine PtXIP sequences distributed within three XIP groups. Comprehensive PtXIP gene expression patterns showed that only two isoforms (PtXIP2;1 and PtXIP3;2) were transcribed in vegetative tissues. However, their patterns are contrasted, PtXIP2;1 was ubiquitously accumulated whereas PtXIP3;2 was predominantly detected in wood and to a lesser extent in roots. Furthermore, only PtXIP2;1 exhibited a differential expression in leaves and stems of drought-, salicylic acid-, or wounding-challenged plants. Unexpectedly, the PtXIPs displayed different abilities to alter water transport upon expression in Xenopus laevis oocytes. PtXIP2;1 and PtXIP3;3 transported water while other PtXIPs did not.

The uptake and degradation of matrix-bound lipoproteins by macrophages require an intact actin Cytoskeleton, Rho family GTPases, and myosin ATPase activity.

A key cellular event in atherogenesis is the interaction of macrophages with lipoproteins in the subendothelium. In vivo, these lipoproteins are bound to matrix and often aggregated, yet most cell-culture experiments explore these events using soluble monomeric lipoproteins. We hypothesized that the internalization and degradation of matrix-retained and aggregated low density lipoprotein (LDL) by macrophages may involve the actin-myosin cytoskeleton in a manner that distinguishes this process from the endocytosis of soluble LDL. To explore these ideas, we plated macrophages on sphingomyelinase-aggregated LDL bound to smooth muscle cell-derived matrix in the presence of lipoprotein lipase. The macrophages internalized and degraded the LDL, which was mediated partially by the LDL receptor-related protein. Cytochalasin D and latrunculin A, which block actin polymerization, markedly inhibited the uptake and degradation of matrix-retained LDL but not soluble LDL. Inhibition of Rho family GTPases by Clostridium difficile toxin B blocked the degradation of matrix-retained and aggregated LDL by >90% without any inhibition of soluble LDL degradation. However, specific inhibition of Rho had no effect, suggesting the importance of Rac1 and Cdc42. Degradation of matrix-retained, but not soluble, LDL was also blocked by inhibitors of tyrosine kinase, phosphatidylinositol 3-kinase, and myosin ATPase. These findings define fundamental cytoskeletal pathways that may be involved in macrophage foam cell formation in vivo but have been missed by the use of previous cell culture models.

Identification of a pollen-specific sucrose transporter-like protein NtSUT3 from tobacco.

Pollen cells are symplasmically isolated during maturation and germination. Pollen therefore needs to take up nutrients via membrane carriers. Physiological measurements on pollen indicate sucrose transport in the pollen tube. A cDNA encoding a pollen-specific sucrose transporter-like protein NtSUT3 was isolated from a tobacco pollen cDNA library. NtSUT3 expression is detected only in pollen and is restricted to late pollen development, pollen germination and pollen tube growth. Altogether these data indicate that pollen is supplied not only with glucose, but also with sucrose through a specific sucrose transporter. The respective contribution of each transport pathway may change during pollen tube growth.

Induction of cellular cholesterol efflux to lipid-free apolipoprotein A-I by cAMP.

In the present study apolipoprotein-mediated free cholesterol (FC) efflux was studied in J774 macrophages having normal cholesterol levels using an experimental design in which efflux occurs in the absence of contributions from cholesteryl ester hydrolysis. The results show that cAMP induces both saturable apolipoprotein (apo) A-I-mediated FC efflux and saturable apo A-I cell-surface binding, suggesting a link between these processes. However, the EC50 for efflux was 5-7-fold lower than the Kd for binding in both control and cAMP-stimulated cells. This dissociation between apo A-I binding and FC efflux was also seen in cells treated for 1 h with probucol which completely blocked FC efflux without affecting apo A-I specific binding. Thus, cAMP-stimulated FC efflux involves probucol-sensitive processes distinct from apo A-I binding to its putative cell surface receptor. FC efflux was also dramatically stimulated in elicited mouse peritoneal macrophages, suggesting that cAMP-regulated apolipoprotein-mediated FC efflux may be important in cholesterol homeostasis in normal macrophages. The presence of a cAMP-inducible cell protein that interacts with lipid-free apo A-I was investigated by chemical cross-linking of 125I-apo A-I with J774 cell surface proteins which revealed a Mr 200 kDa component when the cells were treated with cAMP.

Scavenger receptor BI (SR-BI) mediates free cholesterol flux independently of HDL tethering to the cell surface.

In addition to its effect on high density lipoprotein (HDL) cholesteryl ester (CE) uptake, scavenger receptor BI (SR-BI) was recently reported to stimulate free cholesterol (FC) flux from Chinese hamster ovary (CHO) cells stably expressing mouse SR-BI, a novel function of SR-BI that may play a role in cholesterol removal from the vessel wall where the receptor can be found. It is possible that SR-BI stimulates flux simply by tethering acceptor HDL particles in close apposition to the cell surface thereby facilitating the movement of cholesterol between the plasma membrane and HDL. To test this, we used transiently transfected cells and compared the closely related class B scavenger receptors mouse SR-BI and rat CD36 for their ability to stimulate cholesterol efflux as both receptors bind HDL with high affinity. The results showed that, although acceptor binding to SR-BI may contribute to efflux to a modest extent, the major stimulation of FC efflux occurs independently of acceptor binding to cell surface receptors. Instead our data indicate that SR-BI mediates alterations to membrane FC domains which provoke enhanced bidirectional FC flux between cells and extracellular acceptors.

Regulation of a plant plasma membrane sucrose transporter by phosphorylation.

The protein phosphatase inhibitor okadaic acid (OA) either provided directly to sugar beet (Beta vulgaris L.) leaf discs or infiltrated in the leaf blade rapidly inhibited sucrose uptake. Methyl okadaic acid, a biologically inactive analogue of OA, had only a marginal effect on uptake. OA inhibited proton-motive force-driven uptake of sucrose into plasma membrane vesicles, without affecting their proton permeability. OA did not significantly affect the amount of sucrose transporters present in the vesicles, as estimated by ELISA with specific antibodies. It is concluded that OA directly inhibits the activity of a H+-sucrose cotransporter of the plant plasma membrane, likely by maintaining it in a phosphorylated form.

Fatty acid composition of an oral load affects chylomicron size in human subjects.

HDL-phospholipids are determinants in reverse cholesterol transport. They are mostly derived from triacylglycerol (TG)-rich lipoproteins. Chylomicron size is important, therefore, because it is related to the ratio surface phospholipids: core TG and, thus, determines the availability of postprandial phospholipids for transfer to HDL. Eleven healthy young women each ingested four different fat loads supplemented with retinyl palmitate and containing 60 g sunflower oil (SO), oleic-sunflower oil (OSO), mixed oil (MO; (g/kg) linoleic acid 480, oleic acid 380, linolenic acid 13) or beef tallow (BT). At the peak of TG absorption for all loads (4 h) chylomicron diameters, determined by agarose-gel filtration, were larger after SO compared with OSO (P < 0.05) and BT (P = 0.06) and after MO compared with BT (P < 0.05). At 6 h chylomicron size was larger after the vegetable oils compared with BT (P < 0.05 in each case). After each fat load chylomicron size decreased at 6 and 8 h compared with that at 4 h (P < 0.05) except for OSO. Retinyl ester and TG concentrations were lower in chylomicrons after BT than after the other fats but not in the chylomicron-free serum (containing chylomicron remnants), suggesting absorption in the form of very small particles. Compared with the fasting value, the concentration of the Svedberg unit of flotation 20-400 fraction, which contains VLDL and chylomicron remnants, was lower 8 h after MO, the only fat to contain significant amounts of linolenic acid. We conclude that chylomicron size is dependent on the fatty acid composition of ingested fats and the time-course of digestion, being larger for polyunsaturated fatty acid-rich fats and in the early phase of digestion. On the basis of retinyl ester concentration there were no differences between fats in chylomicron-remnant clearance.

Cutting, ageing and expression of plant membrane transporters.

The activity and the expression of sucrose, hexose and amino acid transporters were studied with fresh, cut or aged tissues and plasma membrane vesicles (PMV) of mature sugar beet (Beta vulgaris L.) leaves. Cutting and ageing both induced an increase of the transcripts coding for sucrose transporters and hexose transporters. No significant effect could be detected on the amino acid transporter transcripts with the probe used (aap1). A polyclonal serum directed against the Arabidopsis thaliana sucrose transporter (AtSUC1) reacted with a 42 kDa band of the sugar beet PMV, confirming previous biochemical identification of this band as a sucrose transporter. ELISA assays run with microsomal fractions and PMV using the AtSUC1 sucrose transporter probe indicated that ageing, and to a lesser extent cutting, increased the amount of sucrose transporter present in the plasma membrane. However, while cutting strongly stimulated proton-motive force driven uptake of sucrose in PMV, ageing only resulted in a slight stimulation. These data give evidence for transcriptional, post-transcriptional and post-translational controls of the activity of the sucrose transporter by mechanical treatments. Proton-motive force driven uptake of 3-O-methylglucose and valine in PMV was strongly stimulated in PMV from aged tissues, although previous data had shown that cutting did not affect theses processes. Therefore, the plant cells possess various levels of control mechanisms that allow them to regulate fluxes of the main assimilates across the plasma membrane when their natural environment is directly or indirectly altered.

Transcriptional and post-translational control of the plant plasma membrane H(+)-ATPase by mechanical treatments.

The activity of the plant plasma membrane (PM) H(+)-ATPase was studied with fresh, cut or aged tissues of sugar beet (Beta vulgaris L.) leaves. The rate of acidification of the medium by tissue samples was strongly stimulated by ageing, but unaffected by cutting. The proton-pumping activity and the specific activity of the vanadate-sensitive ATPase of purified PM vesicles prepared from aged tissues were much higher than that of fresh tissues, whereas cutting had no effect. Yet, both ageing and cutting increased the amount of PM H(+)-ATPase detected by enzyme-linked immunosorbent assays. Likewise, both ageing and cutting increased the levels of pma4 and pma2 ATPase transcripts, as assayed with the corresponding probes from Nicotiana plumbaginifolia. Ageing increases, within a few hours, the levels of the transcripts, the translation and the activity of several PM H(+)-ATPase families. Cutting, which represents a milder mechanical stress, only increases the levels of the transcripts and their translation, without detectable effect on the activity at the biochemical or physiological level, which suggests a post-translational control of this activity. Thus, upon mechanical stress, the activity of the H(+)-ATPase, a key enzyme of the plant PM is rapidly and tightly regulated by transcriptional and post-translational controls.

Oleic acid-rich fats increase the capacity of postprandial serum to promote cholesterol efflux from Fu5AH cells.

Cell cholesterol efflux to serum is stimulated after an oral fat load. The impact of meal fatty acid composition was explored by measure of serum promoted cholesterol efflux from Fu5AH cells after ingestion of 4 different fats: sunflower (Sf), oleic-sunflower (Ol), a mixed oil (Mx), and beef tallow (Bt). High density lipoprotein (HDL)2 and HDL3 were isolated and analyzed. Cholesterol efflux increased regularly after Ol (P<0.05 at 4 h and P<0.02 at 8 h), and 8 h after Mx (P<0.02) or Bt (P<0.05), but not after Sf. Percent HDL3 phospholipids increased after Ol (P<0.05 at 6 h and P<0.01 at 8 H) and 8 h after Mx (P<0.01). After Ol, variations in efflux and percent phospholipids in HDL3 (but not HDL2) were positively correlated (r=0.929; P=0.007 at 6 h). Using HDL3, efflux increased 6 h after Ol (P<0.05) but not after Sf, and efflux was correlated with HDL3 phospholipid concentration in medium (r=0.913; P=0.011). Thus postprandial increase in cholesterol efflux in influenced by ingested fats in relation to increased phospholipid availability on HDL3. The protective effect of monounsaturated fatty acids against atherogenesis might be partly mediated by an enhanced ability of postprandial serum to accept cell cholesterol.

Postprandial free fatty acids stimulate activity of human corticosteroid binding globulin.

The effect of postprandial variation of free fatty acids (FFA) on serum corticosteroid binding globulin (CBG) properties and cortisol (hydrocortisone) concentrations were explored in 11 women (20-30 yr) during 8 h after an oral load of tallow (26% C16:0, 18% C18:0, and 43% C18:1), oleic-sunflower (oleic-SF; 73% C18:1), sunflower (SF; 67% C18:2), and mixed oil (MO; 39% C18:1 and 48% C18:2). Serum FFA increased little after SF and MO but more than doubled in the late postprandial period (6 and 8 h) after oleic-SF (due to monounsaturated FFA) or tallow (due to saturated and monounsaturated FFA). CBG concentrations remained unchanged, but in relation with the postprandial elevation of serum FFA, CBG binding activity was increased after tallow or oleic-SF as a result of a combined two- to threefold increase in affinity constant and a 50% reduction in binding sites. Immunological and in vitro binding studies showed the changes in CBG behavior to be conformational and to be mediated mainly by monounsaturated FFA, especially C18:1. The modifications of CBG properties were associated with sustained high concentrations of cortisol (suppression of midday decrease) 6 and 8 h after tallow or oleic-SF. Thus dietary FFA may have an impact on bioavailability of glucocorticoids.

Immunoregulatory potential of exogenous Schistosoma mansoni soluble egg antigen in a model of experimental schistosomiasis--I. Regulation of granuloma formation in vivo.

This study was undertaken to assess the optimum conditions required to reduce the vigorous host granulomatous reaction around Schistosoma mansoni eggs. Soluble schistosomal egg antigen (SEA) at a concentration of 10 or 100 micrograms protein was administered i.p. or i.v. into unprimed C57BL/6 mice. SEA was injected either alone or in combination with cyclophosphamide (CY) 100 or 50 mg/kg via i.p. route. Seven or 14 days later viable eggs of S. mansoni were injected via the tail vein into treated groups and untreated normal controls. Mice were sacrificed 8, 16 and 24 days after the injection of eggs. The lungs were removed for histopathological study, measurement of granuloma diameter and phenotypic analysis of granuloma intralesional T-cell subsets. Compared to untreated controls, the lower concentration of SEA (10 micrograms) administered by the i.v. route 7 days before egg injection, induced a significant reduction in granuloma diameter 16 days after egg injection than that by the i.p. route or at a higher SEA concentration (100 micrograms). Compared to untreated controls, the higher dose of CY (100 mg/kg), given i.p. alone or in combination with 10 micrograms SEA by the i.v. or i.p. route, induced a significant reduction in granuloma diameter, while 50 mg/kg CY did not cause any reduction. The reduction in granuloma diameter by i.v. administration of low SEA concentration alone or in combination with CY IP, was associated with a decrease in the granuloma intralesional L3T4+/Lyt2+ ratio. The decrease in the ratio was due to an increase in Lyt2+ cells. The results suggest that the use of low dose SEA by the i.v. route alone or combined with an immunosuppressive drug ameliorates pathological changes concurrent with S. mansoni infection.

Preventive action of garlic on aflatoxin B1-induced carcinogenesis in the toad Bufo regularis.

The action of fresh minced garlic and garlic oil on aflatoxin B1- (AFB1) induced carcinogenesis in the toad Bufo regularis was studied. Feeding toads with AFB1 induced tumors in 19% of the animals. Animals given AFB1 together with fresh garlic or garlic oil showed a significant reduction in tumor incidence. The tumor incidences were 3% and 9% in animals given AFB1 plus garlic and AFB1 plus garlic oil, respectively. In all three groups, the tumors were located in the liver (hepatocellular carcinomas), in addition to the kidney in animals treated with AFB1 alone and together with garlic. The kidney tumors were diagnosed as metastatic deposits from the primary liver tumors. It is speculated that one or more constituents of garlic may be responsible for inhibition of AFB1-induced carcinogenesis in B. regularis.

Binding of HDL to basolateral membranes of the renal cortex. Evidence for two components in the HDL-membrane association.

The binding of porcine 125I-HDL to purified basolateral membrane fractions isolated from pig kidney cortex displays two categories of sites, one with high affinity ((Kd = (3.0 +/- 0.7) x 10(-9) M) and low capacity (Bmax = 52 +/- 32 ng/mg proteins) another with low affinity (Kd = (5.3 +/- 0.7) x 10(-8) M) but a higher capacity (Bmax = 795 +/- 115 ng/mg proteins). Binding was competitively inhibited to the same extent by unlabeled HDL from swine, human or rat, demonstrating an absence of species specificity. Porcine LDL partially competed for binding even in the presence of 30 mM EDTA which prevents apo B/E specific binding. Membrane proteins solubilized with CHAPS were analyzed by electrophoresis followed by ligand blotting using porcine 125I-HDL and 125I-apoAI-HDL to show that HDL bound to two proteins of respective molecular masses 120 +/- 2 and 95 +/- 9 kDa. 125I-apoAI associated mostly with the 95 kDa protein. A 100-fold excess of unlabeled HDL greatly decreased binding to the 95 kDa protein but less to the 120 kDa protein. We conclude that part of HDL binding occurs through the lipid moiety, while another is the result of a specific interaction between apoAI and a membrane protein of 95 kDa.