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PubMed2005

Disparate regulation and function of the class A scavenger receptors SR-AI/II and MARCO.

The macrophage class A scavenger receptors, macrophage receptor with a collagenous structure (MARCO) and type I/II class A scavenger receptor (SR-AI/II), share structural features and roles in host defense, but little is known about their regulation and signaling properties. Ligation of MARCO on mouse thioglycollate-elicited peritoneal macrophages (PEMs) with immobilized mAb costimulated IL-12 production, in contrast to previously reported inhibition by SR-AI/II. PEMs from MARCO-deficient mice exhibited 2.7 times lower IL-12 production in responses to stimulation with LPS and IFN-gamma and lack of significant IL-12 production on stimulation with LPS alone. Conversely, SR-AI/II-deficient PEMs produced 2.4 and 1.8 times more IL-12 than wild-type PEMs in response to LPS or LPS and IFN-gamma, respectively. Corresponding differences in regulation of SR-A and MARCO expression were also observed. Th1 adjuvants (LPS, a CpG motif-containing oligodeoxynucleotide (CpG-ODN), IL-12, and GM-CSF) increased, whereas Th2-polarizing factors (IL-4, M-CSF, and non-CpG ODN) decreased expression of MARCO on J774 macrophage-like cells. Expression of SR-A was regulated in the opposite manner to MARCO or not affected. Whereas MARCO was involved in opsonin-independent phagocytosis in CpG-ODN-pretreated but not in IL-4-pretreated J774 cells, anti-SR-A Abs inhibited particle uptake in untreated and IL-4-pretreated but not in CpG-ODN-pretreated cells. SR-A and MARCO are regulated differently and mediate distinct negative and positive effects on IL-12 production in macrophages. These differences may contribute to sustained Th1 or Th2 polarization of ongoing immune responses.

Animals↗

PubMed1992

[Apolipoprotein AI levels in cord blood].

Lipid is known to increase during pregnancy but the factors responsible for the change have not been established. In addition, the lipid concentration in preeclamptic pregnancy is significantly higher than in normal pregnancy. The apolipoproteins are an important determinant of metabolism and the structure of plasma lipoproteins. The 26 healthy pregnant women, the levels of cord apolipoprotein AI were determined by TIA methods. The cord and plasma apolipoprotein AI were 76.12 +/- 20.04 mg/dl (n = 26, mean +/- S.D.) and 190.50 +/- 18.84 mg/dl, respectively. Cord apolipoprotein levels correlated to maternal age (r = -0.12, p less than 0.05), maternal weight (r = -0.11, p less than 0.01), the gestational week (r = +0.42, p less than 0.01), infant weight (r = -0.01, p less than 0.05), placental weight (r = -0.03, p less than 0.05), and diastotlic blood pressure (r = +0.06, p less than 0.05). These data suggest that the measurement of cord apolipoprotein AI may be a useful factor in evaluating preeclamptic pregnancy.

Adult↗

PubMed2004

[Measurement of pulse wave "augmentation index (AI) "and its clinical application].

Hypertension, hyperlipidemia, diabetes mellitus and obesity, all of these life-style related diseases advance arteriosclerosis and cause a cardiovascular event. It is said that the event can be greatly reduced by improvement of lifestyle or medication. The device is recently developed that enables us easily to measure AI i.e. augmentation index, and the studies applying the device have been clarifying the clinical usefulness of the index. The reflected wave from the peripheral artery is superimposed on the ejection wave generated by cardiac contraction, although the blood pressure waveform is observed as the synthesized one of those two. AI is defined as the proportion of the amplitude of the reflected wave to that of the ejection wave, and it does not only express a cardiac load, but also arterial stiffness. The vessel with arteriosclerosis generates a large reflected wave, and it reaches the left ventricle at high speed. Thereby the heart receives large mechanical stress which may cause cardiac hypertrophy, and as a result, the sustained stress may cause a serious accident. Thus, it is the management for both situations of the heart and the artery that matters, and AI can be regarded as a new marker of cardiovascular disease for suitable clinical management on both heart and artery.

Arteriosclerosis↗

PubMed2005

Identification of bovine leucocyte adhesion deficiency (BLAD) carriers in Holstein and Brown Swiss AI bulls in Iran.

BLAD is a hereditary disease in Holstein dairy cattle. The defective allele of CD18 gene which is responsible for this disease has a recessive inheritance. The recessive homozygous form (BL/BL) is lethal and since carrier animals have viability, BLAD frequency increases by use of carrier bulls in Artificial Insemination (AI). BLAD carriers can be detected easily by means of polymerase chain reaction followed by restriction analysis of the amplicons. In this study DNA samples from Holstein (n = 30) and Brown Swiss (n = 10) bulls from Abbas Abad AI center (Khorasan state of Iran) were analysed. A 101 bp fragment from the polymorphic region of CD18 gene located on chromosome 1 was amplified by PCR. Restriction enzymes TaqI and HaeIII were used to identify genotypes. Digestion products were screened by electrophoresis on 8% non-denaturing polyacrylamide gel and visualized by ethidium bromide staining. Frequencies of BL/TL (carrier) genotypes in Holstein and Brown Swiss bulls were 3.33% and 0%, respectively. Our pedigree studies of the carrier bull in this experiment revealed that the mutation inherited to him from Hawkeye bull (CANM 369995, BL). Although the elimination of BLAD-carrier bulls from the Holstein world would be the most efficient method to control this genetic disorder, many BLAD-carrier bulls are still listed commercially for AI and BLAD is still occurring in Iran. Monitoring the prevalence of BLAD-carriers in random selected herds may be helpful in judging the effectiveness of the BLAD-control program.

Animals↗

PubMed1991

[Effects of apolipoproteins AI, CI, CII, CIII and E on the binding of 125I-labeled apoE-deficient HDL3 to rat liver plasma membranes].

Effects of purified human apolipoproteins AI, CI, CII, CIII-1, Cs and E on the binding of 125I-labeled apo E-deficient HDL3 to isolated rat liver plasma membranes were investigated. Unlabeled apo AI, CI, CII, CIII-1 and apo Cs, but not apo E, could effectively inhibit 125I-labeled HDL3 binding to liver membranes, apoCIII-1, was the strongest among the apoC subclasses and the inhibition curve of apoCIII-1 was similar to that of apo AI. This result indicates that apo C, especially apo CIII, may be another specific ligand of HDL receptor, and it plays an important role in regulation of HDL receptor activity in liver.

Animals↗

PubMed2006

Etiologic theories of idiopathic scoliosis: the breaking of bilateral symmetry in relation to left-right asymmetry of internal organs, right thoracic adolescent idiopathic scoliosis (AIS) and vertebrate evolution.

In the search to understand the etiology and pathogenesis of adolescent idiopathic scoliosis (AIS) some workers have focused on mechanisms initiated in embryonic life including a disturbance of bilateral (left-right or mirror-image) symmetry highly conserved in vertebrates. The normal external bilateral symmetry of vertebrates results from a default process involving mesodermal somites. The normal internal asymmetry of the heart, major blood vessels, lungs and gut with its glands is also highly conserved among vertebrates. It results from the breaking of the initial bilateral symmetry by a binary asymmetry switch mechanism producing asymmetric gene expression around the embryonic node and/or in the lateral plate mesoderm. In the mouse this switch occurs during gastrulation by cilia driving a leftward flow of fluid and morphogen(s) at the embryonic node (nodal flow) that favors precursors of the heart, great vessels and viscera on the left. Based on the non-random laterality of thoracic AIS curves, the hypothesis is suggested that an anomaly of the binary asymmetry switch explains the excess of right/left thoracic AIS. Some support for this hypothesis is the prevalence of right and left scoliosis curve laterality associated with situs inversus. There is recent evidence that vertebrates within their bilateralised shell retain an archaic left-right asymmetric visceral body organization evident in thoracic and abdominal organs.

Adolescent↗

PubMed1991

[Plasma apolipoproteins B and AI in healthy individuals and patients with coronary atherosclerosis in a male population from Lithuania].

The paper discusses the results from a study into apolipoproteins B (apo-B) and AI (apo-AI) and apoB/apo-AI ratios in the blood of 188 healthy donors and 122 male patients with coronary atherosclerosis. Atherosclerotic lesions were coronary angiographically documented. The study was performed (in two age groups of patients: 1) those under 45 years and 2) those over 45 years. A relationship was examined between the levels of apolipoproteins and the lesion of one, two, three or more coronary arteries in the two age groups. The studies indicate that there are various mechanisms responsible for the pathogenesis of atherosclerosis in the age groups in question. It is concluded that the younger a patient is, the higher probability that elevated blood apo-B levels are essential in the pathogenesis of coronary atherosclerosis is. Determination of plasma apo-B and apo-AI levels and apo-B/apo-AI ratios enables a potential number of diseased coronary arteries to be predicted.

Adult↗

PubMed1991

[Immunohistochemical study for the localization of apolipoprotein AI, B100, and E in normal and psoriatic skin].

Recently many new knowledge about the LDL receptors and LDL-receptor mediated endocytosis of cholesterol have been reported (Goldstein et al. 1979). This phenomenon is also observed in keratinocyte. The use of low density lipoprotein-gold (LDL-gold) technique in electron microscopy demonstrated a reciprocal correlation between cell differentiation and LDL-receptor expression in normal and psoriatic skin which is characterized by keratotic disorder and epidermal hyperproliferation. (Mommaas-Kienhuis et al. 1987). In order to study the interaction between normal skin and lipid, and the affect of lipid to psoriatic skin, we investigated the localization of apolipoprotein AI, B100 and E in epidermis. Six normal skins, ten psoriatic skins and three skins of seborrheic dermatitis were obtained. In normal epidermis, apolipoprotein B100 was markedly detected intercellularly, and apolipoprotein E was observed intracellularly. In contrast, apolipoprotein AI was not detected in epidermis. This result showed that keratinocytes expressed B and E receptors on their surface membrane, connecting with apolipoprotein B100 and apolipoprotein E respectively. But this finding that positive reaction sites were found in all layer of epidermis also suggested that anti-apolipoprotein B100 antibody reacted extracellular cholesterol excreted outside from keratinocytes. In psoriatic skin, the basement membrane of dermo-epidermal junction, the vascular walls and perivascular regions in papillary dermis were stained positively by anti-apolipoprotein AI antibody. But the localization of apolipoprotein B100 and E were similar to normal skin, and they were also detected in the parakeratotic regions in horny layer. These results did not show the relationship between cell differentiation and B, E receptor expression on keratinocyte. And it is suggested that cholesterol metabolism in keratinocyte affected the pathogenesis of psoriasis.

Apolipoprotein A-I↗

PubMedDate not supplied

Problems with the measurement of apolipoproteins AI and AII.

There is considerable evidence demonstrating that increased levels of low density lipoprotein (LDL) cholesterol and decreased levels of high density lipoprotein (HDL) cholesterol are associated with coronary artery disease (CAD). Yet, these lipoprotein markers are insensitive for identifying risk of CAD. Measurement of subcomponents of HDL may offer more sensitive markers. Investigators have focused on protein components (apolipoproteins) of HDL as a potentially important marker. Unfortunately, because much of the immunoreactivity of apolipoproteins is hidden as a result of an association with lipids, it is difficult to measure them accurately. Detergents and other denaturing agents have been used to expose immunoreactivity. Poor correlations among different methods suggest that some detergents presently used may not be adequate for effective measurement of apolipoprotein (APO) AI. Studies using denaturing agents to probe HDL particles indicate that APO AII immunoreactivity is more resistant to exposure than that of APO AI. Data presented here indicate that the immunoreactivity of APO AII can be increased up to 50 percent by treatment with 4M guanidine provided the concentration of guanidine is diluted to less than 50 mM in the assay system. Previous studies failed to notice this effect because high levels of guanidine inhibited the antibody-antigen reaction in the immunoassay, making it appear that APO AII had not been exposed. It is concluded that with our present state of knowledge, it is unclear which, if any apolipoprotein assays, are adequately designed to achieve optimal exposure of antigenic sites, but that pretreatment with guanidine may be a simple, effective way to optimize APO AI and APO AII assays for clinical purposes.

Antigen-Antibody Reactions↗

PubMed1989

[Changes in AI, B and E apolipoproteins induced by infusion of lipid emulsions in critical patients].

In 24 critically ill patients HDL, LDL and VLDL values and those of apolipoproteins (apo) AI, B and E were evaluated just before (T0) and after 1 (T1), 3 (T3), 5 (T5) hours of intralipid infusion. Baseline levels of such parameters were compared with those obtained in 26 healthy volunteers. The critically ill patients showed lower values of apo AI and B (p less than 0.001) than control patients. In intensive care unit patients, a close relationship between HDL and apo AI (p less than 0.001) and between LDL and apo B (p less than 0.001) was observed in addition to the evidence of apo B and E interconversion. In fact, these apolipoproteins were always significantly correlated (p less than 0.01 a T0 e T3; p less than 0.001 a T1; p less than 0.05 a T5). The knowledge of the apolipoproteins functions could be important for the understanding and the detection of the negative effects that could follow to the infusion of fat emulsions.

Adult↗

PubMed1986

Time-related severity scaling of head injuries--discussion on the AIS-severity code--early and late.

The deficiencies of the present severity scaling of head injuries involve the absence of factors such as age, impact site etc. Moreover there is a terrible lack of agreement and of possibilities of translation between the AIS and the coma scales, presently more wellknown among neurosurgeons. The importance of noting the time after trauma for AIS-codifying must also be stressed, as well as of the presence of intoxication. A modified AIS-scale (EIS) is suggested to facilitate comparison with coma scales such as GCS, as well with the diagnostic terminology suggested for ICD 10 later in this supplement. An attempt to use the EIS as a late scaling after the "transition period" of the second to fourth week after injury is also suggested as a basis for a prediction of late residual disabilities.

Age Factors↗

PubMed1978

A fluorescent probe study of salmine AI.

A fluorescent probe, 1-p-toluidinylnapthalene-8-sulfonate (1,8-TNS), was used to study the nonpolar sites on salmine AI. Fluorescence enhancement resulting from binding between the probe and the protein occurs at a wavelength of maximum emission of 497-500 nm, indicating the existence of moderately nonpolar binding sites on salmine AI. Fluorescence enhancement decreases as the ionic strength of the solvent is increased from 0.002 M to 0.050 M. Fluorescence increases with increasing acidity although this effect is not correlated to the pKa of 1,8-TNS. Positive cooperative binding takes place between 1,8-TNS and salmine AI. Equilibrium dialysis indicates that binding occurs only under conditions resulting in significant fluorescent enhancement. The binding was also studied using thin film dialysis, which is much faster than equilibrium dialysis and avoids the observed changes in probe-protein interaction that occur over long time periods with the latter system.

Animals↗

PubMed1981

[The detection of apolipoproteins AI and B in the liver of patients with and without hyperlipoproteinemia (author's transl)].

Liver sections as well as isolated liver cells from 5 patients with a normal liver and normal serum lipids and patients with familial hyperlipoproteinemia type IIa (n=6), type IIb (n=11), type IV (n=13) and type V (n=2) were studied for the presence of apolipoprotein (apo) AI and B by immunofluorescence technique. At the time of liver biopsy the actual serum concentrations of HDL- and LDL-cholesterol and triglycerides were determined. In patients without metabolic disturbances apo AI was detectable in hepatocytes in 2 out of 5 cases. Apo B was not found in the liver of these patients. The non-parenchymal liver cells did not show depositions of apoproteins. In the group of 32 patients with hyperlipoproteinemia 6 cases showed in the liver apo AI and 2 cases apo B. The apoproteins exhibited a granular fluorescence pattern in the cytoplasm of hepatocytes. There was no correlation between the apoproteins in the liver and the degree of fat depositions in hepatocytes or the concentrations of serum lipids. The results indicate that the fat droplets in hepatocytes of patients with hyperlipoproteinemia represent lipid particles free of apoproteins. The lack of apoproteins in the liver with elevation of lipids in serum can be explained with a disturbed hepatic clearance function for lipoproteins.

Adult↗

PubMed1982

Porcine parvovirus: serological examinations in pig breeding herds and AI boar centres.

From several reports PPV is known to be world wide disseminated in pig herds. Only few reports, however, are concerned about the prevalence of PPV infection among breeding animals within individual pig breeding herds. In the present work 1858 sows and boars from 53 conventional pig breeding herds and 731 sows from 73 SPF pig breeding herds were examined for antibody to PPV, and the herds were grouped according to the prevalence of PPV antibody positive animals. More than 90% of the animals examined were PPV antibody positive in 57% and 30% of the conventional herds and the SPF herds, respectively, while a variable number of animals were positive in the remaining herds. At 2 performance test stations and 2 isolation camps 302 and 148 boars, respectively, were examined for antibody to PPV and 76% and 97% of the boars were found low titered or negative for PPV antibody. After installation of 41 PPV antibody negative boars at 6 different AI boar centres, all of 11 boars installed at one AI boar centre seroconverted to PPV within 4 months. At the remaining AI boar centres either few or none of the boars examined seroconverted to PPV indicative for low levels or absence of infection with PPV during the investigation period.

Animals↗

PubMed1993

Monoclonal antibodies to apolipoprotein AI: generation and characterization.

BALB/c mice were immunized with apolipoprotein (apo AI)--high density lipoprotein (HDL) conjugate. By polyethylene glycol-induced fusion of isolated spleen cells with the myeloma cell line P3 X63 Ag8 6.5.3, three different hybridomas were obtained and characterized. Two of them were found to secrete antibodies of the IgG2a subclass, whereas the third produced antibodies of the IgG1 type. Binding capacities to 125I-apo AI and 125I-HDL were higher than 90% in all cases. The isolated antibodies recognize independent epitopes on the apo AI molecule and bind isolated HDL and serum-HDL with different affinities.

Animals↗

PubMed1995

Inverse relation of physical activity and apolipoprotein AI to blood pressure in elderly women.

To study the relation of habitual physical activity, diet, and serum lipoproteins to blood pressure, a cross-sectional study was carried out in a cohort of 202 women, age 60-69 yr. Sitting, supine, and standing blood pressure was measured with a standard sphygmomanometer. Physical activity was assessed by questionnaire, diet by food records, serum lipoprotein cholesterol enzymatically, and apolipoprotein AI turbidimetrically. Among the women not taking antihypertensive medication (N = 127), the physically most active (physical activity 5 times per week or more) had sitting diastolic blood pressure of 86 mm Hg (adjusted for high-density-lipoprotein cholesterol, body mass index, and cardiovascular health status), which was 8 mm Hg lower (P = 0.007) than in the least active (physical activity twice per week or less) women. Subjects in the highest tertile of apolipoprotein AI (> 1.46 g.l-1) had a mean sitting systolic blood pressure of 147 mm Hg (adjusted for age, body mass index, and cardiovascular health status), which was 16 and 13 mm Hg lower (P = 0.001) than in women in the middle and lowest tertiles (< 1.32 g.l-1), respectively. The present data suggest that, in elderly women, regular physical activity is associated with a clinically significant lowering of diastolic blood pressure. Moreover, a higher level of serum apolipoprotein AI, the major protein component of high-density lipoprotein particles, is inversely associated with systolic blood pressure.

Aged↗

PubMed1996

DNA polymorphisms of apolipoprotein B and AI-CII-AIV genes in a Brazilian population: a preliminary report.

Possible associations between coronary heart disease (CHD) and restriction fragment length polymorphisms (RFLPs) in the apo AI-CII-AIV cluster and the apo B gene were investigated in a Brazilian population consisting of 46 patients with CHD and 24 individuals without evidence of CHD. A preliminary genetic analysis of SstI RFLP in the apo AI-CII-AIV cluster showed a significantly higher frequency of the rare SstI allele (S2) in CHD patients as compared with controls. No significant differences were found in the frequencies of PstI RFLP in the apo AI-CII-AIV cluster or XbaI and EcoRI RFLPs in the apo B gene between CHD patients and controls. Moreover, no association was seen between the RFLPs studied and myocardial infarction or plasma cholesterol or triglyceride levels.

Adult↗

PubMed1997

Anticipatory postural adjustment and T'ai Chi Ch'uan.

Recently much attention has focused on T'ai Chi Ch'uan as a method of improving balance and reducing the risk of falls in the elderly. Little has been done to determine the mechanism of these improvements. This study examined the effects of a sixteen week training program on anticipatory postural adjustments (APA). Eight subjects (median age 36.5) in good health, with no prior training in T'ai Chi were tested. The battery of tests included load dropping of 2.2 kg loads by the subjects standing on an unstable board placed on a force platform. The level and direction of instability were varied. The results show counterintuitive reductions in the APAs of several muscle groups while the stability of standing improved. We interpret the findings as an indication that practicing T'ai Chi leads to a greater use of the elasticity of the peripheral structures involving muscles, ligaments, and tendons while the participation of the central neutral structures in postural equilibrium is decreased.

Adult↗