scholarly journals Species pattern of phosphatidylinositol from lung surfactant and a comparison of the species pattern of phosphatidylinositol and phosphatidylglycerol synthesized de novo in lung microsomal fractions

1988 ◽  
Vol 254 (1) ◽  
pp. 67-71 ◽  
Author(s):  
B Rüstow ◽  
Y Nakagawa ◽  
H Rabe ◽  
K Waku ◽  
D Kunze
Keyword(s):  
Lung Function ◽  
Molecular Species ◽  
De Novo ◽  
Lung Surfactant ◽  
Minor Component ◽  
Main Species ◽  
Surfactant Phospholipids ◽  
Species Pattern ◽  
A Minor

1. Phosphatidylinositol (PI) is a minor component of lung surfactant which may be able to replace the functionally important phosphatidylglycerol (PG) [Beppu, Clements & Goerke (1983) J. Appl. Physiol. 55, 496-502] without disturbing lung function. The dipalmitoyl species is one of the main species for both PI (14.4%) and PG (16.9%). Besides the C16:0--C16:0 species, the C16:0--C18:0, C16:0--C18:1, C16:0--C18:2 and C18:0--C18:1 species showed comparable proportions in the PG and PI fractions. These similarities of the species patterns and the acidic character of both phospholipids could explain why surfactant PG may be replaced by PI. 2. PI and PG were radiolabelled by incubation of microsomal fractions with [14C]glycerol 3-phosphate (Gro3P). For 11 out of 14 molecular species of PI and PG we measured comparable proportions of radioactivity. The radioactivity of these 11 species accounted together for more than 80% of the total. The addition of inositol to the incubation system decreased the incorporation in vitro of Gro3P into PG and CDP-DG (diacylglycerol) of lung microsomes (microsomal fractions), but did not change the distribution of radioactivity among the molecular species of PG. These results supported the idea that both acidic surfactant phospholipids may be synthesized de novo from a common CDP-DG pool in lung microsomes.

scholarly journals Phosphatidylglycerol of rat lung Intracellular sites of formation de novo and acyl species pattern in mitochondria, microsomes and surfactant

1986 ◽  
Vol 240 (1) ◽  
pp. 247-252 ◽  
Author(s):  
M Schlame ◽  
B Rüstow ◽  
D Kunze ◽  
H Rabe ◽  
G Reichmann
Keyword(s):  
Fatty Acid Composition ◽  
Fatty Acid ◽  
De Novo ◽  
Lung Surfactant ◽  
Rat Lung ◽  
Major Species ◽  
Species Pattern ◽  
Formation De Novo ◽  
Phosphate Incorporation

The subcellular site of phosphatidylglycerol (PG) formation for lung surfactant has not been convincingly clarified. To approach this problem we analysed the acyl species pattern of lung PG in mitochondria, microsomes and surfactant by h.p.l.c. separation of its 1,2-diacyl-3-naphthylurethane derivatives. Both mitochondrial and microsomal PG proved identical with surfactant PG, containing the major species 1-palmitoyl-2-oleoyl-PG and 1,2-dipalmitoyl-PG. The fatty acid composition of mitochondrial PG differs markedly from that of diphosphatidylglycerol. This may be taken as an indication that mitochondrial PG is synthesized on purpose to form surfactant, rather than being only the precursor of diphosphatidylglycerol. In vitro, sn-[U-14C]glycerol 3-phosphate incorporation into PG of mitochondria or microsomes occurs in the presence of CTP, ATP and CoA but independently of the supply of exogenous lipoidic precursors. Although the rate in vitro of autonomous PG synthesis, and the endogenous PG content, are higher in mitochondria than in microsomes, it is assumed that both subcellular fractions are involved in PG formation for surfactant.

scholarly journals Murine B-cell subpopulations responsive to T-dependent and T-independent antigens.

1976 ◽  
Vol 144 (2) ◽  
pp. 382-397 ◽  
Author(s):  
G K Lewis ◽  
R Ranken ◽  
D E Nitecki ◽  
J W Goodman
Keyword(s):  
B Cells ◽  
B Cell ◽  
Minor Component ◽  
Memory Cell ◽  
Keyhole Limpet Hemocyanin ◽  
The Other ◽  
Other Hand ◽  
Cell Mitogen ◽  
A Minor

Strain A/J mice made secondary indirect plaque-forming cell (PFC) responses to azobenzenearsonate (ABA) conjugates of giant keyhole limpet hemocyanin (KLH), a thymic-dependent antigen, but not to conjugates of Ficoll, a T-independent antigen. ABA-Ficoll was also unable to elicit a response in animals primed with ABA-KLH, which have an expanded anti-ABA memory cell pool. On the other hand, ABA-Ficoll rendered mice unresponsive to ABA-KLH when administered before priming or boosting with the T-dependent immunogen. Hence, the T-independent antigen was able to tolerize but unable to trigger B-memory cells responsive to the T-dependent antigen. A/J mice immunized with dinitrophenyl conjugates of Ficoll or bovine IgG (BGG) made vigorous IgM and IgG PFC responses. PFC responses to ABA-KLH and 2,4-dinitrophenyl (DNP)-BGG were abrogated by depleting mice of C3 with cobra venom factor, whereas the IgM and IgG PFC responses to DNP-Ficoll were unaffected. B lymphocytes were fractionated on the basis of receptors for C3 and the subpopulations were assayed for in vitro PFC responses to DNP-Ficoll. Very little response was obtained from complement receptor lymphocyte [CRL(+)] B cells, whereas CRL(-) cells were more responsive than unfractionated B cells. Both populations responded to a polyclonal B-cell mitogen (lipopolysaccharide). On the other hand, the in vitro PFC response to a T-dependent antigen (sheep erythrocytes) correlated with the presence of CRL(+) B cells in the cultures. However, a minor component of this response, sensitive to anti-Thy-1 serum, was made by CRL(-) B cells, indicating the existence of subpopulations of T-dependent B cells with different signalling requirements. The results suggest that most B cells responsive to T-dependent antigens possess receptors for C3 and that C3 plays an obligatory role in the response of these cells. A distinct subpopulation of B cells which lack C3 receptors respond to T-independent antigens. The precursors of PFC for the ABA epitope reside largely or exclusively in the CRL(+) compartment in A/J mice, whereas precursors for the DNP determinant are found in both compartments.

Immediate response of the hemoglobin system of the goldfish, Carassius auratus, to temperature change

1976 ◽  
Vol 54 (10) ◽  
pp. 1737-1741 ◽  
Author(s):  
A. H. Houston ◽  
R. Rupert
Keyword(s):  
Temperature Regime ◽  
Carassius Auratus ◽  
Environmental Temperature ◽  
De Novo ◽  
Minor Component ◽  
System Complexity ◽  
Hemoglobin Synthesis ◽  
Goldfish Carassius Auratus ◽  
Cycling Temperature

Goldfish acclimated to 3 and 23 °C were characterized by two- and three-component hemoglobin systems, respectively. After acclimation to a diurnally cycling temperature regime (~3 to ~23 °C), specimens sampled at ~23 °C and ~3 °C were identical in terms of hemoglobin system complexity with those held at equivalent constant temperatures. Abrupt transfer of fish acclimated at constant 23 °C to 3 °C, and vice versa, lead to appearance or disappearance of the minor component, G.1, within 3 h. In vitro cooling and warming of whole blood and hemolyzate samples indicated that hemoglobin system modification occurred under cell-free as well as cell-intact conditions. These observations suggest that previously observed quantitative variations in the hemoglobin systems of thermally acclimated teleosts may represent, in part at least, altered aggregation of preexisting subunits rather than de novo hemoglobin synthesis and raise the possibility that teleostean hemoglobin systems may possess a capacity for rapid, adaptative reorganization after environmental temperature variation.

scholarly journals MAP 1C is a microtubule-activated ATPase which translocates microtubules in vitro and has dynein-like properties.

1987 ◽  
Vol 105 (3) ◽  
pp. 1273-1282 ◽  
Author(s):  
B M Paschal ◽  
H S Shpetner ◽  
R B Vallee
Keyword(s):  
Atpase Activity ◽  
Heavy Chain ◽  
Sedimentation Coefficient ◽  
Minor Component ◽  
High Molecular Mass ◽  
Microtubule Associated Proteins ◽  
Associated Proteins ◽  
Axonemal Dynein ◽  
A Minor

We observe that one of the high molecular mass microtubule-associated proteins (MAPs) from brain exhibits nucleotide-dependent binding to microtubules. We identify the protein as MAP IC, which was previously described in this laboratory as a minor component of standard microtubule preparations (Bloom, G.S., T. Schoenfeld, and R.B. Vallee, 1984, J. Cell Biol., 98:320-330). We find that MAP 1C is enriched in microtubules prepared in the absence of nucleotide. Kinesin is also found in these preparations, but can be specifically extracted with GTP. A fraction highly enriched in MAP 1C can be prepared by subsequent extraction of the microtubules with ATP. Two activities cofractionate with MAP 1C upon further purification, a microtubule-activated ATPase activity and a microtubule-translocating activity. These activities indicate a role for the protein in cytoplasmic motility. MAP 1C coelectrophoreses with the beta heavy chain of Chlamydomonas flagellar dynein, and has a sedimentation coefficient of 20S. Exposure to ultraviolet light in the presence of vanadate and ATP results in the production of two large fragments of MAP 1C. These characteristics suggest that MAP 1C may be a cytoplasmic analogue of axonemal dynein.

scholarly journals Aerosol delivery of dry powder synthetic lung surfactant to surfactant-deficient rabbits and preterm lambs on non-invasive respiratory support

2019 ◽  
Vol 3 ◽  
pp. 6 ◽  
Author(s):  
Frans J. Walther ◽  
Monik Gupta ◽  
Michael M. Lipp ◽  
Holly Chan ◽  
John Krzewick ◽  
...  
Keyword(s):  
Lung Function ◽  
Surface Activity ◽  
Lung Surfactant ◽  
Respiratory Support ◽  
Low Flow ◽  
Synthetic Surfactant ◽  
Aerosol Delivery ◽  
Dry Powder ◽  
Non Invasive

Background: The development of synthetic lung surfactant for preterm infants has focused on peptide analogues of native surfactant proteins B and C (SP-B and SP-C). Non-invasive respiratory support with nasal continuous positive airway pressure (nCPAP) may benefit from synthetic surfactant for aerosol delivery. Methods: A total of three dry powder (DP) surfactants, consisting of phospholipids and the SP-B analogue Super Mini-B (SMB), and one negative control DP surfactant without SMB, were produced with the Acorda Therapeutics ARCUS® Pulmonary Dry Powder Technology. Structure of the DP surfactants was compared with FTIR spectroscopy, in vitro surface activity with captive bubble surfactometry, and in vivo activity in surfactant-deficient adult rabbits and preterm lambs. In the animal experiments, intratracheal (IT) aerosol delivery was compared with surfactant aerosolization during nCPAP support. Surfactant dosage was 100 mg/kg of lipids and aerosolization was performed using a low flow inhaler. Results: FTIR spectra of the three DP surfactants each showed secondary structures compatible with peptide folding as an α-helix hairpin, similar to that previously noted for surface-active SMB in other lipids. The DP surfactants with SMB demonstrated in vitro surface activity <1 mN/m. Oxygenation and lung function increased quickly after IT aerosolization of DP surfactant in both surfactant-deficient rabbits and preterm lambs, similar to improvements seen with clinical surfactant. The response to nCPAP aerosol delivery of DP surfactant was about 50% of IT aerosol delivery, but could be boosted with a second dose in the preterm lambs. Conclusions: Aerosol delivery of DP synthetic surfactant during non-invasive respiratory support with nCPAP significantly improved oxygenation and lung function in surfactant-deficient animals and this response could be enhanced by giving a second dose. Aerosol delivery of DP synthetic lung surfactant has potential for clinical applications.

scholarly journals Escherichia coli as a platform for the study of phosphoinositide biology

2019 ◽  
Vol 5 (3) ◽  
pp. eaat4872 ◽  
Author(s):  
Sergio Botero ◽  
Rachel Chiaroni-Clarke ◽  
Sanford M. Simon
Keyword(s):  
Escherichia Coli ◽  
Minor Component ◽  
Signaling Cascades ◽  
Membrane Biology ◽  
E Coli ◽  
A Minor ◽  
Phosphatidylinositol 4

Despite being a minor component of cells, phosphoinositides are essential for eukaryotic membrane biology, serving as markers of organelle identity and involved in several signaling cascades. Their many functions, combined with alternative synthesis pathways, make in vivo study very difficult. In vitro studies are limited by their inability to fully recapitulate the complexities of membranes in living cells. We engineered the biosynthetic pathway for the most abundant phosphoinositides into the bacterium Escherichia coli, which is naturally devoid of this class of phospholipids. These modified E. coli, when grown in the presence of myo-inositol, incorporate phosphatidylinositol (PI), phosphatidylinositol-4-phosphate (PI4P), phosphatidylinositol-4,5-bisphosphate (PIP2), and phosphatidylinositol-3,4,5-trisphosphate (PIP3) into their plasma membrane. We tested models of biophysical mechanisms with these phosphoinositides in a living membrane, using our system to evaluate the role of PIP2 in nonconventional protein export of human basic fibroblast growth factor 2. We found that PI alone is sufficient for the process.

Osteonectin is a minor component of mineralized connective tissues in rat

1986 ◽  
Vol 64 (4) ◽  
pp. 356-362 ◽  
Author(s):  
Paul Zung ◽  
Carmelo Domenicucci ◽  
Safia Wasi ◽  
Fumiyuki Kuwata ◽  
Jaro Sodek
Keyword(s):  
Minor Component ◽  
Crystal Formation ◽  
Connective Tissues ◽  
Adult Rats ◽  
Virtual Absence ◽  
Mineralized Tissues ◽  
Low Levels ◽  
A Minor

Osteonectin is a major glycoprotein of porcine and bovine bones and teeth that is found associated with hydroxylapatite crystal surfaces. From the ability of osteonectin to bind calcium ions, it has been proposed as a possible nucleator of hydroxylapatite crystal formation. Analysis of hydroxylapatite-bound proteins of rat bone and dentine, however, has revealed that osteonectin represents only 2.5 ± 1.5% of the hydroxylapatite-bound protein in long bones, 0.9 ± 0.5% in calvariae, and < 0.1% in incisor dentine of animals of different ages. Further, in vivo pulse–chase studies carried out in young adult rats have shown osteonectin to be synthesized at low levels in these tissues. Similarly, low levels of osteonectin were synthesized by rat calvarial cells in vitro. In contrast, fibroblastic cells from periodontal ligament and gingiva synthesized significantly greater amounts of osteonectin. These studies indicate that the low quantities of osteonectin in rat mineralized tissues are a consequence of low rates of formation rather than being due to rapid turnover. The virtual absence of osteonectin in incisor dentine correlates with the lack of peritubular dentine in rat, whereas the low osteonectin content of rat bones may reflect differences in their structure and biophysical properties compared with bones of larger mammals.

Degradation of Fibrinogen by Proteolytic Enzymes

1968 ◽  
Vol 19 (03/04) ◽  
pp. 499-515 ◽  
Author(s):  
J Sanchez-Avalos ◽  
S. P Miller
Keyword(s):  
Enzymatic Degradation ◽  
Proteolytic Enzymes ◽  
Slow Component ◽  
Minor Component ◽  
Fast Component ◽  
Initial Action ◽  
Main Components ◽  
A Minor

SummaryFibrinogen was subjected to enzymatic degradation by streptokinase-activated plasminogen (plasmin). There was a rapid split of the molecule into large polypeptide components. Four components were seen by electrophoresis in acrylamide gel. Two major components (D and E) were identified by Immunoelectrophoresis and immune diffusion. In addition, a minor component which arose from the slow component and is called D’ was seen.Fibrin degradation yielded a slow component that was identical with the slow component of fibrinogen, but the fast component (E) of fibrin was different from that of fibrinogen.Degradation of fibrinogen by trypsin, chymotrypsin and papain was not mediated through the plasminogen-plasmin system. The initial action of these enzymes yielded fragments which were immunologically identical and electrophoretically similar to those of plasmin, but subsequent action of chymotrypsin led to further degradation of the slow component, while the fast component was subsequently destroyed by papain.The two main components (D and E) could be identified in the plasma and serum of patients suffering from fibrinolytic disorders. The components were immunologically identical with the components produced in vitro by proteolytic enzymes.

scholarly journals A New Sesquiterpene Essential Oil from the Native Andean Species Jungia rugosa Less (Asteraceae): Chemical Analysis, Enantiomeric Evaluation, and Cholinergic Activity

Plants ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2102
Author(s):  
Karyna Calvopiña ◽  
Omar Malagón ◽  
Francesca Capetti ◽  
Barbara Sgorbini ◽  
Verónica Verdugo ◽  
...  
Keyword(s):  
Essential Oil ◽  
Minor Component ◽  
Volatile Fraction ◽  
Response Factors ◽  
Phytochemical Study ◽  
Combustion Enthalpy ◽  
Ache Inhibitors ◽  
Polar Column ◽  
A Minor

As part of a project devoted to the phytochemical study of Ecuadorian biodiversity, new essential oils are systematically distilled and analysed. In the present work, Jungia rugosa Less (Asteraceae) has been selected and some wild specimens collected to investigate the volatile fraction. The essential oil, obtained from fresh leaves, was analysed for the first time in the present study. The chemical composition was determined by gas chromatography, coupled to mass spectrometry (GC-MS) for qualitative analysis, and to flame ionization detector (GC-FID) for quantitation. The calculation of relative response factors (RRF), based on combustion enthalpy, was carried out for each quantified component. Fifty-six compounds were identified and quantified in a 5% phenyl-polydimethylsiloxane non-polar column and 53 compounds in a polyethylene glycol polar column, including four undetermined compounds. The main feature of this essential oil was the exclusive sesquiterpenes content, both hydrocarbons (74.7% and 80.4%) and oxygenated (8.3% and 9.6%). Major constituents were: γ-curcumene (47.1% and 49.7%) and β-sesquiphellandrene (17.0% and 17.9%), together with two abundant undetermined oxygenated sesquiterpenes, whose abundance was 6.7–7.2% and 4.7–3.3%, respectively. In addition, the essential oil was submitted to enantioselective evaluation in two β-cyclodextrin-based enantioselective columns, determining the enantiomeric purity of a minor component (1S,2R,6R,7R,8R)-(+)-α-copaene. Finally, the AChE inhibition activity of the EO was evaluated in vitro. In conclusion, this volatile fraction is suitable for further investigation, according to two main lines: (a) the purification and structure elucidation of the major undetermined compounds, (b) a bio-guided fractionation, intended to investigate the presence of new sesquiterpene AChE inhibitors among the minor components.

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