Medical Sciences Commons^™

Detection And Mapping Of Quantitative Trait Loci That Determine Responsiveness, Janet L. Mueller, E. A. Ellenberger, Linda K. Vaughn, John K. Belknap, Raymond M. Quock

Biomedical Sciences Faculty Research and Publications

Exposure to 70% N₂O evokes a robust antinociceptive effect in C57BL/6 (B6) but not in DBA/2 (D2) inbred mice. This study was conducted to identify quantitative trait loci (QTL) in the mouse genome that might determine responsiveness to N₂O. Offspring from the F₂ generation bred from B6 and D2 progenitors exhibited a broad range of responsiveness to N₂O antinociception as determined by the acetic acid-induced abdominal constriction test. QTL analysis was then used to dissect this continuous trait distribution into component loci, and to map them to broad chromosomal regions. To this end, …

The Structure And Biological Features Of Fibrinogen And Fibrin, Michael W. Mosesson, Kevin R. Siebenlist, David A. Meh

Biomedical Sciences Faculty Research and Publications

Fibrinogen and fibrin play important, overlapping roles in blood clotting, fibrinolysis, cellular and matrix interactions, inflammation, wound healing, and neoplasia. These events are regulated to a large extent by fibrin formation itself and by complementary interactions between specific binding sites on fibrin(ogen) and extrinsic molecules including proenzymes, clotting factors, enzyme inhibitors, and cell receptors. Fibrinogen is comprised of two sets of three polypeptide chains termed Aα, Bβ, and γ, that are joined by disulfide bridging within the N-terminal E domain. The molecules are elongated 45-nm structures consisting of two outer D domains, each connected to a central E domain by …

Increased Mrna Expression For The Α1 Subunit Of The GabaA Receptor Following Nitrous Oxide Exposure In Mice, Lisa M. Johanek, William E. Cullinan, Linda K. Vaughn

Biomedical Sciences Faculty Research and Publications

The mechanisms by which nitrous oxide (N₂O) produces physical dependence and withdrawal seizures are not well understood, but both N₂O and ethanol exert some of their effects via the GABA_A receptor and several lines of evidence indicate that withdrawal from N₂O and ethanol may be produced through similar mechanisms. Expression levels of mRNA transcripts encoding several GABA_A receptor subunits change with chronic ethanol exposure and, therefore, we hypothesized that N₂O exposure would produce changes in mRNA expression for the α₁ subunit. Male, Swiss–Webster mice, 10–12 weeks of age, were …

Position Of Γ-Chain Carboxy-Terminal Regions In Fibrinogen/Fibrin Cross-Linking Mixtures, Kevin R. Siebenlist, David A. Meh, Michael W. Mosesson

Biomedical Sciences Faculty Research and Publications

There are conflicting ideas regarding the location of the carboxyl-terminal regions of cross-linked γ-chain dimers in double-stranded fibrin fibrils. Some investigators believe that the chains are always oriented longitudinally along each fibril strand and traverse the contacting ends of abutting fibrin D domains (“DD-long” cross-linking). Other investigations have indicated instead that the chains are situated transversely between adjacent D domains in opposing fibril strands (transverse cross-linking). To distinguish between these two possibilities, the γ dimer composition of factor XIIIa-cross-linked fibrin/fibrinogen complexes that had been formed through noncovalent D/E interactions between fibrinogen D domains and fibrin E domains was examined. Two …

The Location Of The Carboxy-Terminal Region Of Γ Chains In Fibrinogen And Fibrin D Domains, Michael W. Mosesson, Kevin R. Siebenlist, David A. Meh, Joseph S. Wall, James F. Hainfeld

Biomedical Sciences Faculty Research and Publications

Elongated fibrinogen molecules are comprised of two outer “D” domains, each connected through a “coiled-coil” region to the central “E” domain. Fibrin forms following thrombin cleavage in the E domain and then undergoes intermolecular end-to-middle D:E domain associations that result in double-stranded fibrils. Factor XIIIa mediates crosslinking of the C-terminal regions of γ chains in each D domain (the γXL site) by incorporating intermolecular ɛ-(γ-glutamyl)lysine bonds between amine donor γ406 lysine of one γ chain and a glutamine acceptor at γ398 or γ399 of another. Several lines of evidence show that crosslinked γ chains extend “transversely” between the strands of …

Identification And Characterization Of The Thrombin Binding Sites On Fibrin, David A. Meh, Kevin R. Siebenlist, Michael W. Mosesson

Biomedical Sciences Faculty Research and Publications

Thrombin binds to fibrin at two classes of non-substrate sites, one of high affinity and the other of low affinity. We investigated the location of these thrombin binding sites by assessing the binding of thrombin to fibrin lacking or containing γ′ chains, which are fibrinogen γ chain variants that contain a highly anionic carboxyl-terminal sequence. We found the high affinity thrombin binding site to be located exclusively in D domains on γ′ chains (K_a, 4.9 × 10⁶⁻¹; n, 1.05 per γ′ chain), whereas the low affinity thrombin binding site was in the fibrin E …

Plasma Factor Xiii Binds Specifically To Fibrinogen Molecules Containing Γ‘ Chains, Kevin R. Siebenlist, David A. Meh, Michael W. Mosesson

Biomedical Sciences Faculty Research and Publications

The difference between peak 1 and peak 2 fibrinogen lies in their γ chains. Peak 1 molecules contain 2 γA chains; peak 2 molecules contain 1 γA and 1 γ‘ chain, the latter of which contains a 20 amino acid extension (γ‘ 408−427) replacing the carboxyl-terminal 4 amino acids of the γA chain (γA 408−411). While the existence of γ‘ chains in plasma fibrinogen molecules has been known for many years, their function remains unknown. When fibrinogen is purified from plasma, the factor XIII zymogen (A₂B₂) copurifies with it and is found only in the peak …

The Relationship Between The Fibrinogen D Domain Self-Association/Cross-Linking Site (Gammaxl) And The Fibrinogen Dusart Abnormality (Aalpha R554c-Albumin): Clues To Thrombophilia In The "Dusart Syndrome", Michael W. Mosesson, Kevin R. Siebenlist, James F. Hainfeld, J. S. Wall, C. Soria, J. P. Caen

Biomedical Sciences Faculty Research and Publications

Cross-linking of fibrinogen at its COOH-terminal gamma chain cross-linking site occurs in the presence of factor XIIIa due to self-association at a constitutive D domain site ("gammaXL"). We investigated the contribution of COOH-terminal regions of fibrinogen Aalpha chains to the gammaXL site by comparing the gamma chain cross-linking rate of intact fibrinogen (fraction I-2) with that of plasma fraction I-9, plasmic fraction I-9D, and plasmic fragment D1, which lack COOH-terminal Aalpha chain regions comprising approximately 100, approximately 390, and 413 residues, respectively. The cross-linking rates were I-2 > I-9 > 1-9D = D1, and indicated that the terminal 100 or more Aalpha …

Evidence For Intramolecular Cross-Linked Aα·Γ Chain Heterodimers In Plasma Fibrinogen, Kevin R. Siebenlist, Michael W. Mosesson

Biomedical Sciences Faculty Research and Publications

A peptide band of ∼105 kDa migrating near the γ dimer position of disulfide bond reduced human plasma fibrinogen prepared from fresh single donor or outdated plasma was identified by SDS−PAGE. The band, amounting to ∼2% of the total Aα/γ chain population, was thrombin and plasmin sensitive and reacted with antibodies to Aα or γ chains but not with antibodies to Bβ chains, plasminogen, or factor XIII. Amino acid sequencing revealed a double sequence corresponding to that of Aα and γ chains, indicating that the band consists of covalently cross-linked Aα·γ chain heterodimers. Aα·γ heterodimers were identified as a component …

The Role Of Fibrinogen D Domain Intermolecular Association Sites In The Polymerization Of Fibrin And Fibrinogen Tokyo Ii (Γ275 Arg→Cys), Michael W. Mosesson, Kevin R. Siebenlist, James P. Diorio, M. Matsuda, James F. Hainfeld, J. S. Wall

Biomedical Sciences Faculty Research and Publications

Intermolecular end-to-middle domain pairing between a thrombin-exposed 'A' polymerization site in the central 'E' domain of fibrin, and a constitutive complementary 'a' site in each outer 'D' domain ('D:E'), is necessary but not alone sufficient for normal fibrin assembly, as judged from previous studies of a congenital dysfibrinogen, Tokyo II (gamma 275 arg-->cys), which showed defective fibrin clot assembly and a normal D:E interaction (Matsuda, M., M. Baba, K. Morimoto, and C. Nakamikawa, 1983. J. Clin. Invest. 72:1034-1041). In addition to the 'a' polymerization site, two other constitutive intermolecular association sites on fibrinogen D domains have been defined: between …

Progressive Cross-Linking Of Fibrin Gamma Chains Increases Resistance To Fibrinolysis, Kevin R. Siebenlist, Michael W. Mosesson

Biomedical Sciences Faculty Research and Publications

In the presence of plasma transglutaminase (factor XIIIa) fibrin first undergoes intermolecular covalent cross-linking between its gamma chains to create gamma dimers followed by slower cross-linking among its alpha chains to form alpha polymers. Progressive cross-linking of gamma chain dimers occurs at the slowest rate, resulting in gamma trimers and gamma tetramers (“gamma multimers”). Most studies indicate that cross-linked fibrin clots become resistant to fibrinolysis, but the basis for this event is not clear. In this study, we explored the role of gamma chain multimerization compared with alpha polymerization as causal factors in time-dependent development of resistance to fibrinolysis. Fibrin …

Evidence For A Second Type Of Fibril Branch Point In Fibrin Polymer Networks, The Trimolecular Junction, Michael W. Mosesson, James P. Diorio, Kevin R. Siebenlist, Joseph S. Wall, James F. Hainfeld

Biomedical Sciences Faculty Research and Publications

Fibrin molecules polymerize to double-stranded fibrils by intermolecular end-to-middle domain pairing of complementary polymerization sites, accompanied by fibril branching to form a clot network. Mass/length measurements on scanning transmission electron microscopic images of fibrils comprising branch points showed two types of junctions. Tetramolecular junctions occur when two fibrils converge, creating a third branch with twice the mass/length of its constituents. Newly recognized trimolecular junctions have three fibril branches of equal mass/length, and occur when an extraneous fibrin molecule initiates branching in a propagating fibril by bridging across two unpaired complementary polymerization sites. When trimolecular junctions predominate, clots exhibit nearly perfect …

The Polymerization And Thrombin-Binding Properties Of Des-(Bβ1-42)-Fibrin, Kevin R. Siebenlist, James P. Diorio, A. Z. Budzynski, Michael W. Mosesson

Biomedical Sciences Faculty Research and Publications

Multiple factors affect the thrombin-catalyzed conversion of fibrinogen to fibrin, including: fibrinopeptide (FPA and FPB) release leading to exposure of two types of polymerization domains (“A” and “B,” respectively) in the central portion of the molecule, and exposure of a noncatalytic “secondary” thrombin-binding site in fibrin. Fibrinogen containing the FPA sequence but lacking the Bβ 1-42 sequence (“des-(Bβ 1-42)-fibrinogen”), was compared to native fibrinogen (containing both FPA and FPB) to investigate the role played by Bβ 1-42 in the polymerization of α-fibrin (i.e. fibrin lacking FPA), to compare reptilase and thrombin cleavage of FPA from fibrinogen, and …

Fibrinogen Birmingham: A Heterozygous Dysfibrinogenemia (Aα 16 Arg → His) Containing Heterodimeric Molecules, Kevin R. Siebenlist, J. T. Prchal, Michael W. Mosesson

Biomedical Sciences Faculty Research and Publications

Fibrinogen was isolated from the plasma of a 25-year-old female with a history of mild bleeding and several recent moderate to severe hemorrhagic episodes. Coagulability with thrombin approached 100% and varied directly with the time of incubation with the enzyme. High- performance liquid chromatography analysis of thrombin-induced fibrinopeptide release demonstrated retarded fibrinopeptide A (FPA) and fibrinopeptide B (FPB) release and the presence of an abnormal A peptide (FPA) amounting to 50% of the total. The same biochemical abnormalities were found in her asymptomatic father. Amino acid analysis and carboxypeptidase digestion of FPA demonstrated the substitution of His for Arg at …

Studies On The Ultrastructure Of Fibrin Lacking Fibrinopeptide B (Β-Fibrin), Michael W. Mosesson, James P. Diorio, Michael Muller, John R. Shainoff, Kevin R. Siebenlist, D. L. Amrani, G. L. Homandberg, J. Soria, C. Soria, M. Samama

Biomedical Sciences Faculty Research and Publications

Release of fibrinopeptide B from fibrinogen by copperhead venom procoagulant enzyme results in a form of fibrin (beta-fibrin) with weaker self-aggregation characteristics than the normal product (alpha beta-fibrin) produced by release of fibrinopeptides A (FPA) and B (FPB) by thrombin. We investigated the ultrastructure of these two types of fibrin as well as that of beta-fibrin prepared from fibrinogen Metz (A alpha 16 Arg----Cys), a homozygous dysfibrinogenemic mutant that does not release FPA. At 14 degrees C and physiologic solvent conditions (0.15 mol/L of NaCl, 0.015 mol/L of Tris buffer pH 7.4), the turbidity (350 nm) of rapidly polymerizing alpha …

Increased Metabolic Rate In X-Linked Hypophosphatemic Mice, Linda K. Vaughn, Ralph A. Meyer, M. H. Meyer

Biomedical Sciences Faculty Research and Publications

Hyp mice are a model for human X-linked hypophosphatemia, the most common form of vitamin D-resistant rickets. It has previously been observed that Hyp mice have a greater food consumption per gram body weight than do normal mice. This led to the search for some alteration in metabolism in Hyp mice. We found that oxygen consumption was significantly higher in Hyp mice than in normal C57BL/6J mice and this was accompanied by an increased percentage of cardiac output being delivered to organs of heat production (liver and skeletal muscle), to the skin, and to bone and a decreased percentage to …

The Effects Of Triethyltin Bromide On Red Cell And Brain Cyclic Amp-Dependent Protein Kinases, Kevin R. Siebenlist, Fumito Taketa

Biomedical Sciences Faculty Research and Publications

Triethyltin bromide activates the cyclic AMP-dependent protein kinases of human red cell membranes and of bovine brain. Additions of 25-500 microM triethyltin to red cell ghosts resulted in enhanced phosphorylation of ghost proteins. When added to partially purified cyclic AMP-dependent protein kinases from red cell ghosts or bovine brain, stimulation of the phosphorylation of calf thymus histone was observed. The enhancement of kinase activity was due to release of catalytic subunits from the intact protein kinase. Brief exposure of the partially purified enzymes to triethyltin, followed by DE52 chromatography, resulted in elution profiles for regulatory and catalytic subunits that were …

Antibiotic Susceptibility Of Black-Pigmented Bacteroides Isolates From The Human Oral Cavity, Linda Jean Laatsch, Paul R. Hohenfeldt, William L. Kos

Biomedical Sciences Faculty Research and Publications

The minimal inhibitory concentrations of penicillin and six other antibiotics were determined for 66 oral black-pigmented Bacteroides isolates by using the National Committee for Clinical Laboratory Standards proposed standard agar dilution technique. These results plus iodometric determination of β-lactamase activity showed that oral isolates of black-pigmented Bacteroides are remaining relatively susceptible to commonly used antibiotics.

The Esophageal Propulsive Force: Esophageal Response To Acute Obstruction, Daniel H. Winship, F. Frank Zboralske

Biomedical Sciences Faculty Research and Publications

The response of the normal human esophagus to an obstructing intraluminal bolus was investigated and compared to the response evoked by transient intraluminal distention. A balloon, immobilized within the esophagus by external attachment to a force transducer, was inflated with from 3 to 25 ml of air for from 3 to 210 sec. Pressure phenomena occurring in the esophagus were simultaneously recorded from the body of the esophagus above and below the balloon.

Transient distention (5 sec or less) with small volumes (5 ml or less) often evoked a secondary peristaltic wave in the esophagus distal to the balloon, but …

Studies Of The Mechanism By Which Chronic Metabolic Acidosis Augments Urinary Calcium Excretion In Man, Jacob Lemann Jr., John R. Litzow, Edward J. Lennon

Biomedical Sciences Faculty Research and Publications

We carried out clearance studies in nine healthy adults and four patients with hypoparathyroidism before and after inducing stable metabolic acidosis with either NH₄Cl or acetazolamide. Clearances were repeated in seven normal subjects and three of the patients 3 days after stopping these agents.

During acidosis in the normal subjects, serum ultrafilterable calcium concentration rose significantly, but inulin clearance fell to a greater extent, so that the calculated filtered load of calcium fell significantly. Despite this, urinary calcium excretion rose. Urinary calcium excretion remained elevated in the recovery studies when the serum ultrafilterable calcium concentration and filtered load …

The Effect Of Treatment Of Acidosis On Calcium Balance In Patients With Chronic Azotemic Renal Disease, John R. Litzow, Jacob Lemann Jr., Edward J. Lennon

Biomedical Sciences Faculty Research and Publications

Small but statistically significant negative calcium balances were found in each of eight studies in seven patients with chronic azotemic renal disease when stable metabolic acidosis was present. Only small quantities of calcium were excreted in the urine, but fecal calcium excretion equaled or exceeded dietary intake. Complete and continuous correction of acidosis by NaHCO₃ therapy reduced both urinary and fecal calcium excretion and produced a daily calcium balance indistinguishable from zero.

Apparent acid retention was found throughout the studies during acidosis, despite no further reduction of the serum bicarbonate concentration. The negative calcium balances that accompanied acid retention …

Pneumonia Due To Mycoplasma In Gnotobiotic Mice: Ii. Localization Of Mycoplasma Pulmonis In The Lungs Of Infected Gnotobiotic Mice By Electron Microscopy, Avrum B. Organick, Kenneth A. Siegesmund, Irving I. Lutsky

Biomedical Sciences Faculty Research and Publications

Organick, Avrum B. (Marquette University School of Medicine, Milwaukee, Wis.), Kenneth A. Siegesmund, and Irving I. Lutsky. Pneumonia due to mycoplasma in gnotobiotic mice. II. Localization of Mycoplasma pulmonis in the lungs of infected gnotobiotic mice by electron microscopy. J. Bacteriol. 92:1164–1176. 1966.—Lesions in lungs of gnotobiotic mice inoculated intranasally with Mycoplasma pulmonis were examined by electron microscopy after osmic acid fixation. At 1 week after infection, mycoplasma cells were found in large numbers in the bronchi at the surface of bronchial epithelial cells and, in smaller numbers, in the alveoli where active phagocytosis by polymorphonuclear leukocytes (PMN) occurred. …

Responses Of The Normal Human To Infusions Of Plasma From Patients With Graves' Disease, Claude D. Arnaud, Hans A. Kneubuhler, Virginia L. Seiling, Bruce K. Wightman, Norman H. Engbring

Biomedical Sciences Faculty Research and Publications

No abstract provided.

The Net Balance Of Acid In Subjects Given Large Loads Of Acid Or Alkali, Jacob Lemann Jr., Edward J. Lennon, A. David Goodman, John R. Litzow, Arnold S. Relman

Biomedical Sciences Faculty Research and Publications

No abstract provided.

Production, Excretion, And Net Balance Of Fixed Acid In Patients With Renal Acidosis, A. David Goodman, Jacob Lemann Jr., Edward J. Lennon, Arnold S. Relman

Biomedical Sciences Faculty Research and Publications

No abstract provided.

Presbyesophagus: Esophageal Motility In Nonagenarians, Konrad H. Soergel, F. Frank Zboralske, John R. Amberg

Biomedical Sciences Faculty Research and Publications

No abstract provided.

The Ultrastructure Of The Intranuclear Rodlet In Certain Nerve Cells, Kenneth A. Siegesmund, C. R. Dutta, C. A. Fox

Biomedical Sciences Faculty Research and Publications

No abstract provided.

Reversible Changes In The Nem-Reactive--Sh Groups Of Hemoglobin On Oxygenation-Deoxygenation, Samuel A. Morell, Peg Hoffman, Valborg E. Ayers, Fumito Taketa

Biomedical Sciences Faculty Research and Publications

No abstract provided.

Measurement Of Arterial Aging In Hypertensive Patients, Francois M. Abboud, John H. Huston

Biomedical Sciences Faculty Research and Publications

No abstract provided.

Studies Of The Rate Of Disappearance Of Labeled Thyroxine From The Intravascular Compartment, Edward J. Lennon, Norman H. Engbring, William W. Engstrom

Biomedical Sciences Faculty Research and Publications

No abstract provided.