Role of apolipoproteins E and C in type V hyperlipoproteinemia.

We report a mechanism of adenosine triphosphate (ATP) to cyclic adenosine monophosphate (cAMP) conversion by the mammalian type V adenylyl cyclase revealed in molecular dynamics (MD) and quantum mechanics/molecular mechanics (QM/MM) simulations. We characterize a set of computationally derived enzyme-substrate (ES) structures showing an important role of coordination shells of magnesium ions in the solvent accessible active site. Several stable six-fold coordination shells of MgA2+ are observed in MD simulations of ES complexes. In the lowest energy ES conformation, the coordination shell of MgA2+ does not include the Oδ1 atom of the conserved Asp440 residue. Starting from this conformation, a one-step reaction mechanism is characterized which includes proton transfer from the ribose O3'H3' group in ATP to Asp440 via a shuttling water molecule and PA-O3A bond cleavage and O3'-PA bond formation. The energy profile of this route is consistent with the observed reaction kinetics. In a higher energy ES conformation, MgA2+ is bound to the Oδ1(Asp440) atom as suggested in the relevant crystal structure of the protein with a substrate analog. The computed energy profile initiated by this ES is characterized by higher energy expenses to complete the reaction. Consistently with experimental data, we show that the Asp440Ala mutant of the enzyme should exhibit a reduced but retained activity. All considered reaction pathways include proton wires from the O3'H3' group via shuttling water molecules.

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Native Gold in the Chudnoe Au-Pd-REE Deposit (Subpolar Urals, Russia): Composition, Minerals in Intergrowth and Genesis

Minerals ◽

10.3390/min11050451 ◽

2021 ◽

Vol 11 (5) ◽

pp. 451

Author(s):

Galina Palyanova ◽

Valery Murzin ◽

Andrey Borovikov ◽

Nikolay Karmanov ◽

Sergei Kuznetsov

Keyword(s):

Native Gold ◽

Microprobe Analysis ◽

Electron Microprobe Analysis ◽

Gold Mineralization ◽

Type I ◽

Type Ii ◽

Subpolar Urals ◽

Type V ◽

Impurity Elements

Composition of native gold and minerals in intergrowth with rhyolites of the Chudnoe Au-Pd-REE deposit (Subpolar Urals, Russia) was studied using optical microscopy, scanning electron microscopy, and electron microprobe analysis. Five varieties of native gold have been identified, based on the set of impurity elements and their quantities, and on intergrown minerals. Native gold in rhyolites from the Ludnaya ore zone is homogeneous and contains only Ag (fineness 720‰, type I). It is in intergrowth with fuchsite or allanite and mertieite-II. In rhyolites from the Slavnaya ore zone, native gold is heterogeneous, has a higher fineness, different sets and contents of elements: Ag, Cu, 840–860‰ (type II); Ag, Cu, Pd, 830–890‰ (III); Ag, Pd, Cu, Hg, 840–870‰ (IV). It occurs in intergrowth with fuchsite, albite, and mertieite-II (type II), or albite, quartz, and atheneite (III), or quartz, albite, K-feldspar, and mertieite-II (IV). High fineness gold (930–1000‰, type V) with low contents of Ag, Cu, and Pd or their absence occurs in the form as microveins, fringes and microinclusions in native gold II–IV. Tetra-auricupride (AuCu) is presented as isometric inclusions in gold II and platelets in the decay structures in gold III and IV. The preliminary data of a fluid inclusions study showed that gold mineralization at the Chudnoe deposit could have been formed by chloride fluids of low and medium salinity at temperatures from 105 to 230 °C and pressures from 5 to 115 MPa. The formation of native gold I is probably related to fuchsitization and allanitization of rhyolites. The formation of native gold II-V is also associated with the same processes, but it is more complicated and occurred later with a significant role of Na-, Si-, and K-metasomatism. The presence of Pd and Cu in the ores and Cr in fuchsite indicates the important role of mafic-ultramafic magmatism.

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Role of autoimmunity in organ allograft rejection: a focus on immunity to type V collagen in the pathogenesis of lung transplant rejection

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00330.2003 ◽

2004 ◽

Vol 286 (6) ◽

pp. L1129-L1139 ◽

Cited By ~ 63

Author(s):

Tina L. Sumpter ◽

David S. Wilkes

Keyword(s):

Lung Transplantation ◽

Lung Transplant ◽

Transplant Rejection ◽

Survival Rates ◽

Definitive Treatment ◽

Solid Organ ◽

Type V Collagen ◽

End Stage ◽

Type V

Lung transplantation is the only definitive treatment modality for many forms of end-stage lung disease. However, the lung is rejected more often than any other type of solid organ allograft due to chronic rejection known as bronchiolitis obliterans (BO). Indeed, BO is the primary reason why the 5- and 7-yr survival rates are worse for the lung than for any other transplanted organ. Alloimmunity to donor antigens is established as the primary mechanism that mediates rejection responses. However, newer immunosuppressive regimens designed to abrogate alloimmune activation have not improved survival. Therefore, these data suggest that other antigens, unrelated to donor transplantation antigens, are involved in rejection. Utilizing human and rodent studies of lung transplantation, our laboratory has documented that a native collagen, type V collagen [col(V)], is a target of the rejection response. Col(V) is highly conserved; therefore, these data indicate that transplant rejection involves both alloimmune and autoimmune responses. The role of col(V) in lung transplant rejection is described in this review article. In addition, the potential role of regulatory T cells that are crucial to modulating autoimmunity and alloimmunity is also discussed.

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Characterization with zonal ultracentrifugation of low-density lipoproteins in type V hyperlipoproteinemia

Biochimica et Biophysica Acta (BBA) - Lipids and Lipid Metabolism ◽

10.1016/0005-2760(84)90250-9 ◽

1984 ◽

Vol 793 (3) ◽

pp. 365-371 ◽

Cited By ~ 7

Author(s):

Enzo Manzato ◽

Adriana Gasparotto ◽

Raffaella Marin ◽

Giovannella Baggio ◽

Goretta Baldo ◽

...

Keyword(s):

Low Density Lipoproteins ◽

Low Density ◽

Type V Hyperlipoproteinemia ◽

Type V

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Eruptive Xanthomas Caused by Primary Type V Hyperlipoproteinemia

Internal Medicine ◽

10.2169/internalmedicine.8142-21 ◽

2022 ◽

Author(s):

Yoshihiro Nakamura ◽

Tsuyoshi Watanabe ◽

Naoho Takizawa ◽

Yoshiro Fujita

Keyword(s):

Eruptive Xanthomas ◽

Type V Hyperlipoproteinemia ◽

Primary Type ◽

Type V

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Promising Role of Calcium Hypochlorite as a Disinfectant: An in vitro Evaluation Regarding its Effect on Type V Dental Stone

The Journal of Contemporary Dental Practice ◽

10.5005/jp-journals-10024-1242 ◽

2012 ◽

Vol 13 (6) ◽

pp. 856-866

Author(s):

Prasanta Kumar Swain ◽

Sharanbasappa C Nagaral ◽

Pawan Kumar Kamalapurker ◽

Ravishankar Damineni

Keyword(s):

Tensile Strength ◽

Bacillus Subtilis ◽

Deleterious Effect ◽

Strength Testing ◽

Calcium Hypochlorite ◽

Resistant Species ◽

Type V ◽

Mixing Water

ABSTRACT Aim The current study has been chosen to evaluate the efficacy of calcium hypochlorite as a disinfecting additive for the gypsum products and its effect on compressive and tensile strength of the set material. It is hypothesized that, the addition of calcium hypochlorite to type V dental stone in sufficient quantity to disinfect the material would have no deleterious effect on compressive or tensile strength. Materials and methods Total of 160 samples made up of type V dental stone were divided broadly into two groups of 80 samples each for the sake of compressive and tensile strength testing in dry and wet conditions: Out of each group, 10 samples without addition of any disinfectant (0% calcium hypochlorite) was compared with other group of 30 samples after adding disinfectant, i.e. each subgroup containing 10 samples each (0.5, 1.0 and 1.5% calcium hypochlorite). Conclusion Within limitations of this in vitro study it is assumed to prepare type V dental stone that contains a disinfectant, has adequate compressive strength and tensile strength, and can significantly act against a resistant species like Bacillus subtilis. Clinical significance When calcium hypochlorite was added to dental stone, extra mixing water was required to produce a material of nearly same pouring consistency. The samples, which were put to microbiological tests, showed effective action of disinfectant on Bacillus subtilis. No deleterious effect on compressive or tensile strength could be found after putting the selected samples with calcium hypochlorite. How to cite this article Swain PK, Nagaral SC, Kamalapurker PK, Damineni R. Promising Role of Calcium Hypochlorite as a Disinfectant: An in vitro Evaluation Regarding its Effect on Type V Dental Stone. J Contemp Dent Pract 2012;13(6):856-866.

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The Clinical, Biochemical, and Familial Presentation of Type V Hyperlipoproteinemia in Childhood

PEDIATRICS ◽

10.1542/peds.59.4.513 ◽

1977 ◽

Vol 59 (4) ◽

pp. 513-525

Author(s):

Peter O. Kwiterovich ◽

J. Ramsay Farah ◽

W. Virgil Brown ◽

Paul S. Bachorik ◽

Stephen B. Baylin ◽

...

Keyword(s):

Insulin Level ◽

Recurrent Abdominal Pain ◽

Enzymatic Activities ◽

Type I ◽

Rare Type ◽

Type Iv ◽

Type V Hyperlipoproteinemia ◽

Therapeutic Diets ◽

Primary Type ◽

Type V

Primary type V hyperlipoproteinemia was identified in two preadolescent children. The propositus (kindred N) was a 10-year-old girl with severely creamy plasma, lipemia retinalis, hypertriglyceridemia (triglyceride level, 6,800 mg/100 ml), and hypercholesterolemia (cholesterol level, 490 mg/100 ml). Her parents and an 8-year-old sister all had endogenous hypertriglyceridemia (type IV hyperlipoproteinemia). In kindred A, an 11-year-old boy had triglyceride levels as high as 1,100 mg/100 ml and recurrent abdominal pain. His father had type V hyperlipoproteinemia; his mother was normal. All three of his older teenage siblings had type IV hyperlipoproteinemia. The enzymatic activities of lipoprotein lipase (LPL), hepatic triglyceride lipase (HTL), and histaminase (H) were studied in postheparin plasma. The LPL level was low in the children and both parents in kindred N. LPL level in kindred A was normal, except for one child with type IV hyperlipoproteinemia. HTL level was normal to above normal in both kindreds. Most patients had a normal H level, but one parent (kindred N) had no preheparin H and very low levels of postheparin H. There was a strong correlation (r = 0.58, significant at < 1% level) between the release of LPL and H but not between HTL and H (r = 0.22). The mean (± 1 S.D.) levels of the enzymes were as follows: LPL, 2.8 ± 0.7 µmol/ml/hr in kindred N and 5.4 ± 2.2 µmol/ml/hr in kindred A; H, 13.4 ± 6.8 units/ml in kindred N and 22.0 ± 11.9 units/ml in kindred A; and HTL, 18.0 ± 7.1 µmol/ml/hr in kindred N and 14.9 ± 6.3 µmol/ml/hr in kindred A. The enzymatic activities of kindreds N and A were significantly different for LPL (P < .001) and H (.025 < P < .05) but not for HTL. All but one child had at least one high insulin level, which was accompanied by hyperglycemia in two children. The hypertriglyceridemia in all but one child was ameliorated on therapeutic diets. These data suggest that the genetic basis of the hypertriglyceridemia in these two families is different and that hyperchylomicronemia in childhood is not confined to the rare type I hyperlipoproteinemia.

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Coordinate expression of secretory phospholipase A2 and cyclooxygenase-2 in activated human keratinocytes

AJP Cell Physiology ◽

10.1152/ajpcell.2000.278.4.c822 ◽

2000 ◽

Vol 278 (4) ◽

pp. C822-C833 ◽

Cited By ~ 34

Author(s):

Krystyna E. Rys-Sikora ◽

Raymond L. Konger ◽

John W. Schoggins ◽

Rama Malaviya ◽

Alice P. Pentland

Keyword(s):

Wound Repair ◽

Human Keratinocytes ◽

Plating Density ◽

Coordinate Expression ◽

Cox 2 ◽

Type V ◽

In Vitro Wounding

PGE2 levels are altered in human epidermis after in vivo wounding; however, mechanisms modulating PGE2 production in activated keratinocytes are unclear. In previous studies, we showed that PGE2 is a growth-promoting autacoid in human primary keratinocyte cultures, and its production is modulated by plating density, suggesting that regulated PGE2 synthesis is an important component of wound healing. Here, we examine the role of phospholipase A2(PLA2) and cyclooxygenase (COX) enzymes in modulation of PGE2 production. We report that the increased PGE2 production that occurs in keratinocytes grown in nonconfluent conditions is also observed after in vitro wounding, indicating that similar mechanisms are involved. This increase was associated with coordinate upregulation of both COX-2 and secretory PLA2 (sPLA2) proteins. Increased sPLA2 activity was also observed. By RT-PCR, we identified the presence of type IIA and type V sPLA2, along with the M-type sPLA2 receptor. Thus the coordinate expression of sPLA2 and COX-2 may be responsible for the increased prostaglandin synthesis in activated keratinocytes during wound repair.

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Distribution of cyclosporine in blood of a renal-transplant recipient with type V hyperlipoproteinemia.

Clinical Chemistry ◽

10.1093/clinchem/33.3.423 ◽

1987 ◽

Vol 33 (3) ◽

pp. 423-428 ◽

Cited By ~ 16

Author(s):

H L Verrill ◽

R E Girgis ◽

R E Easterling ◽

B S Malhi ◽

W F Mueller

Keyword(s):

Renal Transplant ◽

Plasma Lipids ◽

Kidney Tissue ◽

Therapeutic Drug ◽

Type V Hyperlipoproteinemia ◽

High Concentrations ◽

Stage Renal Disease ◽

End Stage ◽

Type V ◽

Severe Type

Abstract A patient with severe type V hyperlipoproteinemia and chronic end-stage renal disease received a renal transplant and therapy with cyclosporine. Concentrations of the drug in plasma as determined by liquid chromatography appeared extraordinarily high for the dose ingested. When we measured the drug in the plasma, plasma cleared by ultracentrifugation, leukocytes, erythrocytes, and whole blood, we found that the high concentrations of cyclosporine were associated with the chylomicrons that always were present in this patient's blood. Cyclosporine added directly to this patient's plasma was less associated with the plasma lipids. Isolated lymphocytes and kidney slices incubated with plasma from this patient bound no more drug than when incubated with nonhyperlipemic plasma containing cyclosporine at a normal therapeutic concentration. We conclude that the cyclosporine associated with the chylomicrons in this patient was not biologically available to either lymphocytes or kidney tissue. We strongly recommend the use of chylomicron-cleared plasma for therapeutic drug monitoring of cyclosporine in type V hyperlipoproteinemic patients.

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Chylomicrons from patients with Type V hyperlipoproteinemia inhibit platelet function

Atherosclerosis ◽

10.1016/0021-9150(85)90016-4 ◽

1985 ◽

Vol 56 (2) ◽

pp. 157-167 ◽

Cited By ~ 22

Author(s):

Michael Aviram ◽

Bianca Furman ◽

J.Gerald Brook

Keyword(s):

Platelet Function ◽

Type V Hyperlipoproteinemia ◽

Type V

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