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At least 37 records · Page 2Linked to original sources
PubMed1988

Role of pancreatic duct occlusion with prolamine (Ethibloc) in necrotizing pancreatitis.

There is evidence that the pancreatic duct plays an important role in the evolution of necrotizing pancreatitis. We hypothesized that occlusion of the pancreatic duct and its smaller ductules with prolamine (Ethibloc) in opossums at risk of severe necrotizing pancreatitis would have a beneficial effect on the progression of the disease. Sixteen opossums underwent bile duct ligation below the entrance of the pancreatic duct. They were divided into four groups at 6 days. Group I (control, n = 5) opossums were killed for histologic observation of the degree of necrosis of the pancreas; group II (n = 5) underwent external drainage of the pancreatic biliary duct; group III (n = 4) had external biliary drainage and ligation of the pancreatic duct; group IV (n = 7) was treated with external biliary drainage and ligation of the main pancreatic duct after instillation of prolamine. Serum amylase, lipase, and calcium values were determined. The pancreas was examined by inspection and histologically at the time of death, and the severity of the disease was determined by quantitation of pancreatic tissue necrosis. All animals in groups II and III died 8 to 14 days after bile duct ligation, and all had severe necrotizing pancreatitis. All animals in group IV survived and were killed at 2 to 10 weeks after prolamine (Ethibloc) injection into the pancreatic duct. A mild edematous pancreatitis was observed in all seven animals. Prolamine (Ethibloc) provided dramatic protection from progressive necrosis. This study does not provide an explanation, but it allows for speculation that ductal injection interrupted the deleterious effect of proteolytic enzymes and their leakage into the interstitial space of the pancreas.

Amylases↗
PubMed1984

[Parotid duct occlusion with prolamine--sequelae of long-term administration in the animal model].

The effects of occlusion of the parotid excretory duct, after injection of a basic aminoacid solution (prolamine), were studied in 12 rabbit parotid glands one year after prolamine application. 40% of the experimental animals present the picture of an extensive abscess-forming sialadenitis both macroscopically and microscopically. The secretory parenchyma of the gland is almost completely eliminated. Remnants of the injected prolamine solution found in the duct system could possibly be responsible for the abscess formation. At the present experimental stage therapeutic application of prolamine in the human parotid gland cannot be recommended.

Abscess↗
PubMed1993

Studies of the zein-like alpha-prolamins based on an analysis of amino acid sequences: implications for their evolution and three-dimensional structure.

alpha-Prolamins are the major seed storage proteins of species of the grass tribe Andropogonea. They are unusually rich in glutamine, proline, alanine, and leucine residues and their sequences show a series of tandem repeats presumed to be the result of multiple intragenic duplication. Two new sequences of alpha-prolamin clones from Coix (pBCX25.12 and pBCX25.10) are compared with similar clones from maize and Sorghum in order to investigate evolutionary relationships between the repeat motifs and to propose a schematic model for their three-dimensional structure based on hydrophobic membrane-helix propensities and helical "wheels." A scheme is proposed for the most recent events in the evolution of the central part of the molecule (repeats 3 to 8) which involves two partial intragenic duplications and in which contemporary odd-numbered and even-numbered repeats arise from common ancestors, respectively. Each pair of repeats is proposed to form an antiparallel alpha-helical hairpin and that the helices of the molecule as a whole are arranged on a hexagonal net. The majority of helices show six faces of alternating hydrophobic and polar residues, which give rise to intersticial holes around each helix which alternate in chemical character. The model is consistent with proteins which contain different numbers of repeats, with oligomerization and with the dense packaging of alpha-prolamins within the protein body of the seed endosperm.

Amino Acid Sequence↗
PubMed1989

Immunocrossreactivity of antisera against grain prolamines of wheat, rye, barley and oats.

Prolamines extracted from wheat (gliadin), rye (secalin), barley (hordein) and oats (avenin) were used to raise antibodies in rabbits. The four prolamines were separated by SDS-PAGE and blotted onto nitrocellulose. The immunocrossreactivity of the separated prolamines with the four antisera was studied. The close botanical relationship between wheat and rye, and to a lesser extent barley, is clearly established. The crossreactivity of gliadin, secalin and hordein with anti-avenin serum was found to be weak. In contrast, avenin shows a strong crossreactivity with anti-gliadin serum.

Animals↗
PubMed1984

[Comparative studies of partial amino acid sequences of prolamins and glutelins from various cereals. VI. Anion exchange chromatography of peptide fractions obtained by cation exchange chromatography].

The main peptide fractions obtained from prolamins and glutelins of wheat, rye, barley, and corn by chymotryptic hydrolysis, gel filtration and cation exchange chromatography [1, 2] were further separated by anion exchange chromatography. The amino-acid compositions of the peptides obtained from wheat, rye and barley prolamins are closely related. Typical compositions are Glx greater than 44, Pro greater than 28, and Phe greater than 7 mol-%. The peptide fractions from corn prolamine are different (Glx greater than 20, Leu greater than 20, Ala greater than 12, Pro greater than 10 mol-%). The peptide fractions from wheat, rye and barley glutelins are less similar. Typical compositions are Glx greater than 30, Pro greater than 15, and Gly greater than 8 mol-%. Most of the fractions from corn glutelin contain many amino-acids with Glx, Leu, and Ala predominating. Wheat differs significantly from the other cereals because of the unique composition of some high molecular weight peptide fractions from glutelin, which are rich in Glx (greater than 49) and Gly (greater than 19 mol-%).

Amino Acid Sequence↗
PubMed1988

The prolamin antibody reactivity against hordein polypeptides in sera from patients with coeliac disease.

The antibody reactivity against the barley prolamin, hordein, was investigated by an immunoblotting technique, in sera from patients with untreated coeliac disease, patients with other gastrointestinal diseases and healthy controls. No characteristic hordein polypeptide antibody pattern could be connected to coeliac disease, as observed in a similar study using different fractions of the wheat prolamin, gliadin. Gliadin- and hordein-immunoadsorbent column experiments demonstrated that the prolamin reactivity originates from the same population of antibodies. It is speculated that distinct antigenic epitopes characteristic for untreated coeliac disease, might reside within a N-terminal repeat region of gliadin.

Adult↗
PubMed1997

A maize zinc-finger protein binds the prolamin box in zein gene promoters and interacts with the basic leucine zipper transcriptional activator Opaque2.

The prolamin box (P-box) is a highly conserved 7-bp sequence element (5'-TGTAAAG-3') found in the promoters of many cereal seed storage protein genes. Nuclear factors from maize endosperm specifically interact with the P-box present in maize prolamin genes (zeins). The presence of the P-box in all zein gene promoters suggests that interactions between endosperm DNA binding proteins and the P-box may play an important role in the coordinate activation of zein gene expression during endosperm development. We have cloned an endosperm-specific maize cDNA, named prolamin-box binding factor (PBF), that encodes a member of the recently described Dof class of plant Cys2-Cys2 zinc-finger DNA binding proteins. When tested in gel shift assays, PBF exhibits the same sequence-specific binding to the P-box as factors present in maize endosperm nuclei. Additionally, PBF interacts in vitro with the basic leucine zipper protein Opaque2, a known transcriptional activator of zein gene expression whose target site lies 20 bp downstream of the P-box in the 22-kDa zein gene promoter. The isolation of the PBF gene provides an essential tool to further investigate the functional role of the highly conserved P-box in regulating cereal storage protein gene expression.

Amino Acid Sequence↗
PubMed1984

Microsurgical approach to pancreatic duct occlusion in the pig by means of a prolamine solution.

Prolamine is an alcoholic solution of zein, with the property of polymerizing within 15 minutes in a humid medium. Such a substance has been injected in the pancreatic duct of 10 pigs with a microsurgical technique, causing complete occlusion. The prolamine gel produces a progressive fibrosclerosis of the exocrine pancreatic parenchyma, sparing the endocrine portion. The resulting pancreatic atrophy avoids the occurrence of inflammatory complications that often hamper surgery on such gland. The 10 pigs under study showed post-operative normal values of blood glucose and insulin, and a decrease in serum alpha-amylase levels. Complications occurred in only one case, and the microscopic pattern was similar in all cases. Microsurgical approach and use of prolamine are considered effective both in pancreatic transplantation and in chronic pancreatitis.

Animals↗
PubMed1995

The involvement of Opaque 2 on beta-prolamin gene regulation in maize and Coix suggests a more general role for this transcriptional activator.

The maize opaque 2 (o2) mutation is known to have numerous pleiotropic effects. Some polypeptides have their expression depressed while others are enhanced. The best characterized effects of the o2 mutation are those exerted on endosperm genes encoding the storage protein class of the 22 kDa alpha-zeins and the ribosome inactivating protein b-32. The Opaque 2 (O2) locus encodes a basic domain-leucine zipper DNA-binding factor, O2, which transcriptionally regulates these genes. In the maize-related grass Coix lacryma-jobi, an O2-homologous protein regulates the 25 kDa alpha-coixin family. We show in this paper that O2 transcriptionally regulates the structurally and developmentally different class of the beta-prolamins. A new O2-binding box was identified in beta-prolamin genes from maize and Coix that, together with the boxes previously identified in other endosperm expressed genes, forms a curious collection of O2 cis elements. This may have regulatory implications on the role of O2 in the mechanism that controls coordinated gene expression in the developing endosperm. Considering that the O2 locus controls at least three distinct classes of genes in maize endosperm, we propose that the O2 protein may play a more general role in maize endosperm development than previously conceived.

Base Sequence↗
PubMed1995

Homologies between prolamins of different minor millets.

Minor millets, viz. Barnyard millet, Proso millet, Little millet, Foxtail millet and Kodo millet, one variety in each grown in Tamil Nadu Agricultural University (TNAU), Coimbatore, Tamil Nadu were selected for the study. The protein contents of the selected decorticated millets were found to be 11.0, 12.3, 12.9, 10.5 and 10.6% respectively. Fractionation of these proteins revealed that prolamin forms major storage protein in Foxtail millet whereas, glutelin forms major storage protein in all the other millets. The extractability was studied using different solvents, viz. isopropyl alcohol, t-butyl alcohol and ethyl alcohol with varying concentration of 2-mercapto ethanol. Electrophoretic pattern of the extracted prolamins from these millets were compared and found that a protein band at the molecular weight range of 20 kD was found homologous in all except Proso millet. The extractability of the 20 kD protein in 90% isopropyl alcohol showed its strong hydrophobic nature.

Amino Acids↗
PubMed1988

Comparative investigations of partial amino acid sequences of prolamins and glutelins from cereals. VIII. Amino acid sequences of glutelin peptides.

The peptide fractions isolated from chymotryptic hydrolysates of wheat, rye and barley glutelins were separated by high-performance liquid chromatography on octadecyl silica gel. The peptides obtained were analysed for their amino acid composition and some also for their amino acid sequence. Characteristic sequences of peptides from wheat glutelin can be grouped into three types. The first type contains a high amount of Gly and frequently Tyr in the N-terminal positions. A typical partial sequence, which occurs repeated in two peptides, is QGQQPGQGQ. Sequences of this type are found in high-molecular-weight subunits. The second type is characterized by the sequence SQn (n = 3-5) followed by a hydrophobic tripeptide e.g., PPF, PVL; the most frequent sequence is SQQQQPPF. Low-molecular-weight subunits contain sequences of this type. The third type, which has partial sequences such as QQPQQPFP, corresponds to typical peptides from prolamin. Most sequences of peptides from rye and barley glutelins can be divided into two groups. The predominant type shows prolamin-like sequences, e.g., PQQPXPQQ with X being F or I. The second type is similar to glycine-rich peptides from wheat glutelin, except that repeating sequences are less frequent.

Amino Acid Sequence↗
PubMed1992

[Extraction and characterization of grain prolamins of 6 sorghum Sorghum bicolor L. Moench cultivars].

The purpose of this work was to isolate and characterize prolamines from grains of sorghum, by their solubility and molecular properties. One variety, Zaraza-1 (SV-V51), and five hybrids (Dekalb-55, Dekalb-64, Wac-5005, Pioneer-815B and Savanna-5) were used. The prolamines, called kafirins, were extracted with 70% isopropanol at 60 degrees C, and then fractionated by two methods: 95% ethanol and gel filtration with Sephadex G-200. The molecular weight was determined by electrophoresis in a discontinuous polyacrylamide gel with sodium dodecyl sulfate (PAGE-SDS). The alpha kafirin (soluble fraction in 95% ethanol), and 7.13% of the grain's total protein, and the beta kafirin represents 21.64% of kafirin (the insoluble fraction), represents 78.36% of the kafirin and 25.39% of total protein. Three fractions were obtained from the column fractionation, two important ones (A and C), and one (B) in a lesser amount. The proportion of these fractions varied between cultivars, so that in SV-V51, D-64 and Wac-5005, A is predominant, and in high tannin sorghum, C is the predominant one. Kafirins reduced with 2-mercaptoethanol were separated in four subunits with molecular weights of: 15,000, 21,300, 24,300 and 51,500 daltons. Unreduced kafirin showed a larger number of subunits (six) whose molecular weights were: 15,000, 24,300, 48,500, 69,000, 80,000 and 93,500 daltons. Reduced and kafirin showed the same number of subunits as those of nonfractioned kafirin reduced with 2-mercaptoethanol.

Chemical Fractionation↗
PubMed1978

Heterogeneity of avenin, the oat prolamin. Fractionation, molecular weight and amino acid composition.

The prolamin, avenin, was extracted from oat seeds and shown to be maximally extractable in 45% (w/w) ethanol. A purification procedure is described and some properties of avenin are examined. As with wheat and barley prolamins, salt soluble and glutelin fractions were simultaneously extracted. Starch gel electrophoresis revealed two novel fractions, which were isolated by ion-exchange chromatography. These fractions have similar amino acid composition, threonine as the N-terminal amino acid and both have a 22 500 molecular weight. It is suggested that the avenin constituents have a common ancestral gene.

Amino Acids↗
PubMed1989

Angioscope-assisted occlusion of venous tributaries with prolamine in in situ femoropopliteal bypass: preliminary results of canine experiments.

Ten mongrel dogs underwent left lower extremity in situ femoropopliteal bypass with femoral vein. A 20 to 25 cm myocutaneous bridge was left between femoral and popliteal anastomoses. A 2.8 mm angioscope was introduced intraluminally to visualize venous tributaries (VT). A balloon occlusion catheter was placed alongside the angioscope and directed in each VT. Prolamine was injected into each VT to effect occlusion. Seven dogs were followed up for 1 week and three dogs for 1 month. A total of 34 VT (range one to five per dog) were available for attempted occlusion. Twenty-nine of 84 (85%) VT were able to be occluded based on comparison of pre-VT and post-VT occlusion angiograms. Poor visualization of VT or VT too small to admit the 5F catheter were reasons for failure. We conclude that (1) in the canine model studied angioscope-assisted occlusion of femoropopliteal during bypass is technically feasible, (2) this technical detail makes unnecessary medial thigh dissection for exposure of the vein graft, and (3) during short-term observation prolamine appeared to be a suitable occluding substance.

Anastomosis, Surgical↗
PubMed1988

A continuous acetic acid system for polyacrylamide gel electrophoresis of gliadins and other prolamines.

A polyacrylamide gel electrophoresis system buffered by acetic acid alone was developed for electrophoresis of prolamines. When applied to gliadin electrophoresis, the acetic acid system produces more bands than does a conventional aluminum lactate-lactic acid system (using 12% acrylamide gels). The acetic acid system is relatively simple, requiring a single buffer component that is universally available in high purity.

Acetates↗
PubMed1983

A simple and rapid dot-immunobinding assay for zein and other prolamins.

A simple method for the immunochemical assay of zein and other prolamins is described. Alcohol-solubilized zein is spotted onto chromatography paper disks or strips, incubated with antiserum (30-60 min), washed with several changes of Tris-buffered saline (10 min), incubated with protein A-peroxidase (30 min), and washed with several changes of Tris-buffered saline (10 min). the binding of zein-specific antibody is visualized by peroxidase-catalyzed color production from 4-chloro-1-naphthol. The method is simple, inexpensive, and rapid (2 h total time) and has potential application to other insoluble antigens.

Densitometry↗
PubMed1990

Detection and estimation of the barley prolamin content of beer and malt to assess their suitability for patients with coeliac disease.

Malt, lager, brown ale, bitter and stout were assessed for their barley prolamin (hordein) content. Monoclonal antibody immunoperoxidase staining of electrophoretically separated samples of beer revealed the presence of immunoreactive hordein. Polyclonal antibody based enzyme linked immunosorbant assays (ELISAs) revealed 1.6 mg of hordein per gram of malt and 1.5 mg per pint in the beers. Patients with coeliac disease should avoid ingestion of beer and foods that contain malt since they contain quantifiable amounts of hordein that is known to exacerbate the condition.

Alkaline Phosphatase↗