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Showing papers by "Saint Louis University published in 1974"



Book
01 Jan 1974

297 citations


Journal ArticleDOI
TL;DR: Observations are consistent with nearly all possible mechanisms of membrane assembly and may suggest that the phospholipid-rich membranes of embryonic muscle are gradually converted during development into calcium-transporting structures by stepwise insertion of the ATPase enzyme and other components of the transport system.

160 citations


Journal ArticleDOI
TL;DR: The patterns of variability of several polymorphic enzymes obtained from 32 North American populations of the pink salmon, Oncorhynchus gorbuscha, are presented and are compatible with the neutral mutation-random drift hypothesis.
Abstract: Within the last ten years our knowledge of the amount of genetic variability present in diploid organisms has increased as the result of the us,e of electrophoretic techniques. In a modest spectrum of diploid organisms, the proportion of polymorphic loci per population has been found to range from 20% to 54%. This high level of genetic variability poses a dilemma for if, as is commonly assumed, many of the loci are maintained polymorphic by balancing selection (like overdominance) an intolerable genetic load will result (Lewontin and Hubby, 1966). Several authors (e.g., Milkman, 1967; Sved et al., 1967) have suggested, based on particular selection models, that high levels of genetic variability need not necessarily result in large loads. Kimura (1968), on the other hand, proposed a hypothesis for maintaining high levels of protein variability in populations without incurring a genetic load at all-the neutral mutation-random drift hypothesis. According to, his hypothesis, many of the protein polymorphisms are the result of selectively neutral mutations established by random genetic drift in populations of finite size. Recently, several investigators (Prakash et al., 1969; O'Brien and Maclntyre, 1969; Selander et al., 1969) have admirably attempted to discern whether the observed patterns of protein polymorphism in natural populations are more compatible with a selection, or with the neutral mutationrandom drift, hypothesis. These attempts have been frustrated to a large measure, in my opinion, by a critical lack of information on the rate of migration (gene flow) between populations. Kimura and Maruyama (1971) have demonstrated mathematically, assuming a stepping-stone model, that moderate rates of migration can be effective in equalizing gene frequencies between populations. Thus, similar gene frequencies in distantly spaced populations may be due to similar balancing selection pressures or to random drift of neutral alleles equalized in frequency by gene flow. The present work is similar to the ones cited above in that it also attempts to explain the observed pattern of protein polymorphisms in natural populations. However, this work differs from them in that between certain populations the rate of migration is zero and the selection intensities can very logically be assumed to, be equal. Between other populations, the rate of migration is suspected to, be great and selection intensities may or may not be equal. Presented in this paper are the patterns of variability of several polymorphic enzymes obtained from 32 North American populations (2,500 individuals) of the pink salmon, Oncorhynchus gorbuscha. The results, I believe, are compatible with the neutral mutation-random drift hypothesis.

136 citations


Journal ArticleDOI
TL;DR: The level of functioning, recurrence of episodes, and quality of life at follow-up assessed in a group of patients formerly hospitalized for mania at the National Institutes of Health are reported.
Abstract: Forty-seven bipolar manic-depressive patients observed to be manic while hospitalized at the NIMH were interviewed an average of 3.2 years after their discharge and 14.7 years after the onset of their illnesses. A close relative was interviewed separately in 30 cases. The patients have had an average of over five episodes of illness. Fifty-seven per cent have been well since hospitalization; 10 per cent have had further episodes requiring treatment but have functioned well in the intervening periods. One-third remain functionally impaired with moderate to severe affective symptoms interfering with work, social and family life.

112 citations


Journal ArticleDOI
TL;DR: The concentration of phosphorylated β-guanidinopropionic acid decreased dramatically, raising the possibility that it, like P-creatine, can serve in a system to regenerate ATP.

106 citations


Journal ArticleDOI
01 Mar 1974-Cancer
TL;DR: A critical review of over 900 mammary carcinomas treated at St. Louis University Hospitals disclosed 13 that fulfilled the histologic picture of lipid‐rich carcinoma that should be regarded as a specific type of mammary cancer.
Abstract: A critical review of over 900 mammary carcinomas treated at St. Louis University Hospitals disclosed 13 that fulfilled the histologic picture of lipid‐rich carcinoma. All clinical and pathologic data were tabulated; 1 case was studied by electron microscopy. Five of the patients were dead within 2 years, and 2 others had evidence of metastatic tumor within 2 years. One patient died 6 years after treatment. On the basis of the following characteristics we believe lipid‐rich carcinomas should be regarded as a specific type of mammary carcinoma: 1. The presence of non‐degenerative lipid material within the cytoplasm of tumor cells; 2. The presence of intramitochondrial crystals; 3. The pattern of metastatic involvement of lymph nodes and the orbit; 4. The presence of intraductal and lobular carcinoma in situ associated with this type of tumor; and 5. The more aggressive clinical behavior.

100 citations


Journal ArticleDOI
TL;DR: The reasonably close correlation between Ca2+ transport activity and the intramembranous particle density during development supports earlier suggestions that the intamem branous particles may represent the Ca2- transport system.

88 citations


Journal ArticleDOI
01 Sep 1974-Cell
TL;DR: Two methylated species of mammalian cytoplasmic RNA from HeLa cells are described and appear to be coded by the nuclear genome, as ethidium bromide has little effect on their transcription.

86 citations


Book ChapterDOI
TL;DR: The chapter provides evidence for the in vivo function of the viral RNA→DNA polymerase and a concise description of the present understanding of the molecular events of oncornavirus replication and cell transformation.
Abstract: Publisher Summary This chapter provides description of the properties and classification of the oncornaviruses and related virus particles that possess RNA→DNA polymerase molecules. The chapter describes the properties of the DNA polymerase activities of oncornaviruses and related particles including the endogenous reaction, the reaction products, and the utilization of external templates. The chapter also deals with the studies on the inhibitors of the viral DNA polymerase, their mechanism of action and their effect on cell transformation and tumor induction. The properties of purified RNA→DNA polymerase and the mechanism of DNA synthesis are also explored. The chapter provides evidence for the in vivo function of the viral RNA→DNA polymerase and a concise description of the present understanding of the molecular events of oncornavirus replication and cell transformation. The chapter also discusses the analysis of viral related base sequences in normal and cancer cells by molecular hybridization with the viral DNA product of the RNA→DNA polymerase, and studies on RNA→DNA polymerase in normal and cancer cells.

86 citations


Journal ArticleDOI
TL;DR: Differences between properties of ionophores in model systems and their kinetic behavior in biological membranes are discussed in the context of isolation-reconstitution studies.

Journal ArticleDOI
TL;DR: The energy required for the active transport of calcium by sarcoplasmic reticulum is derived from the hydrolysis of ATP 1 l or carbamyl phosphate through a transport ATPase that is absolutely dependent upon membrane phospholipids for activity Tr and constitutes about 70% of the protein content of microsomal membranes.
Abstract: The energy required for the active transport of calcium by sarcoplasmic reticulum is derived from the hydrolysis of ATP 1 l or carbamyl phosphate through a transport ATPase that is absolutely dependent upon membrane phospholipids for activity Tr and constitutes about 70% of the protein content of microsomal membranes.f1, The hydrolysis of ATP 8-10 or acetylphosphate occurs with the formation and decomposition of a phosphoprotein intermediate that has several characteristics of an acylphosphate.9 A possible mechanism that relates ATP hydrolysis and Ca transport to the phosphoprotein intermediate may be written as follows :

Journal ArticleDOI
TL;DR: A triglyceride lipase (EC 3.1.3) was purified 1200-fold from homogenates of rat liver by cosedimentation with lysosomes, detergent solubilization, selective elution from carboxymethylcellulose by lipid activator, and gradient elutions from car boxymethyl cellulose.

Journal ArticleDOI
TL;DR: Comparison of the influx rates of protein-bound hormones to the efflux of T4 and T3 revealed an imbalance theoretically correctable only by influx of free hormone that was consistent with a carrier mechanism with a transport maximum.
Abstract: Labeled thyroxine (T4) and triiodothyronine (T3) given by constant intravenous infusion to dogs for 4 hr penetrate both brain and cerebrospinal fluid (CSF). Labeled T4 reached a steady state distribution between serum, CSF, and cerebral cortex tissue water (CCTW). Labeled T3 entered CCTW more readily than T4 but was slower to reach steady state distribution in CSF. Distribution ratios ofendogenous, nonlabeled T3 and T4 between serum, CSF, and CCTW compartments were similar. The more ready brain penetration of T3 is probably due to a less ionized state at pH 7.4 than T4. Failure of labeled albumin to penetrate CSF during the experimental period suggested a greaterpermeability to free than protein-bound hormone. Impaired transport of labeled free T4 into CSF under conditions of T4 loading was consistent with a carrier mechanism with a transport maximum. Comparison of the influx rates of protein-bound hormones to the efflux of T4 and T3 revealed an imbalance theoretically correctable onlyby influx of free ho...

Journal ArticleDOI
TL;DR: PGE1 and PGE2 are about 10–20 times more potent than oxytocin, suggesting a possible physiological role in the regulation of oviposition, and also effective in initiating egglaying.

Journal ArticleDOI
TL;DR: In-vitro cell-mediated immune response of eight children with severe iron-deficiency anaemia was evaluated by blast-cell transformation and in-vItro incorporation of tritiated thymidine into phytohaemagglutinin-stimulated lymphocytes and the phagocytosis and killing function of leucocytes from these same children was studied.

Journal ArticleDOI
01 Aug 1974-Steroids
TL;DR: Experiments were designed to determine whether or not various antiestrogens in direct competition with estradiol-17β (E2) would inhibit the translocation of the estrogen receptor complex from the cytoplasm to nuclei in rat uterine tissue.

Journal ArticleDOI
TL;DR: The β subunit of αβ may facilitate tighter binding of the enzyme to the substrate resulting in a processive mode of nuclease activity, which is supported by two types of experiments.

Journal ArticleDOI
TL;DR: Glucose stimulates the high-affinity processes of chloroquine and amodiaquin accumulation in owl monkey erythrocytes infected with a chloroquin-susceptible strain of Plasmodium falciparum.
Abstract: Glucose stimulates the high-affinity processes of chloroquine and amodiaquin accumulation in owl monkey erythrocytes infected with a chloroquine-susceptible strain of Plasmodium falciparum . Although these erythrocytes have greater ability to accumulate amodiaquin than chloroquine, glucose has relatively less effect on amodiaquin accumulation than on chloroquine accumulation. In contrast to these findings with chloroquine-susceptible P. falciparum , glucose stimulates amodiaquin but not chloroquine accumulation in erythrocytes infected with chloroquine-resistant P. falciparum . This lack of function of a substrate-dependent component of chloroquine accumulation distinguishes chloroquine-resistant from chloroquine-susceptible P. falciparum .

Journal ArticleDOI
TL;DR: A revised and extended version of a theoretical analysis appearing in a previous paper is employed here to study the displacements of a maxillary central incisor and accompanying periodontium reaction resulting from transverse crown loading.

Journal ArticleDOI
TL;DR: Findings lend over-all support to the view that it is possible to develop a “toxemia model” in the subhuman primate.

Journal ArticleDOI
TL;DR: Ritonucleic acids extracted from polyribosomes of cells replicating murine sarcoma-leukemia viruses (M-MSV(MLV) were resolved by electrophoresis on 2.5% polyacrylamide gels and might serve as polycistronic mRNA for the synthesis of large polypeptides that are cleaved to form the smaller viral proteins.

Journal ArticleDOI
TL;DR: A clinicopathologic study suggests that the radiographic appearance of the lesion is pathognomonic and consists of a radiopaque mass surrounded by a thin radiolucent line that is inseparable, radiologically, from the tooth root and is attached to it.

Journal ArticleDOI
TL;DR: A broad endothermic transition was detected in freeze-dried rabbit sarcoplasmic reticulum membranes which is attributable to membrane lipids and is proposed that the activity of the Ca2+ transport ATPase is limited by the local viscosity of the membrane below the transition temperature.

Journal ArticleDOI
TL;DR: The data suggest that poly(U), isolated from polio [32P]RF is the 5′-end of polio minus RNA.

Journal ArticleDOI
TL;DR: Antibodies prepared against the Ca ++ binding protein (C 1 protein) have no influence upon either ATPase activity or Ca ++ transport and ferritin-labeled anti-C 1 antibodies do not bind to microsomes.

Journal ArticleDOI
TL;DR: Two proteins of molecular weights 75,000 and 45,000 were the major labeled polypeptides in the nuclear membrane fractions prepared from infected cells both by the M-band and the discontinuous sucrose gradient methods, and it is suggested that these proteins may be early viral gene products that may play a role in the viral DNA replication.
Abstract: Nuclear membrane fractions were prepared by two procedures from KB cells pulse labeled with [(3)H]thymidine for 5 min late after infection with adenovirus 2: (i) the M-band technique, which yields a sharp peak containing most of the newly synthesized viral DNA, and (ii) the discontinuous sucrose gradient method, which yields three membrane fractions, one which bands at the interface between sucrose layers at density 118 and 120 g/ml and contains most of the newly synthesized viral DNA Studies using cycloheximide to inhibit protein synthesis showed that proteins whose synthesis begins early after infection and occurs in the absence of viral DNA replication are required for viral DNA synthesis late after infection To study the nature of these proteins, nuclear membrane fractions were isolated from cells labeled with [(3)H]leucine from 6 to 24 h postinfection in the presence of arabinosyl cytosine to block viral DNA replication, and were analyzed by electrophoresis in sodium dodecyl sulfate polyacrylamide gels Two proteins of molecular weights 75,000 and 45,000 were the major labeled polypeptides in the nuclear membrane fractions prepared from infected cells both by the M-band and the discontinuous sucrose gradient methods These two proteins were not found in nuclear membrane fractions from uninfected cells It is suggested that the 75,000 and 45,000 proteins may be early viral gene products that may play a role in the viral DNA replication

Journal ArticleDOI
TL;DR: The accuracy of stone casts produced from nine elastomeric impression materials was determined and the most accurate casts were produced from the polyether rubbers and when the cast pour was delayed for a week, this impression material remained accurate.
Abstract: The accuracy of stone casts produced from nine elastomeric impression materials was determined. One polysulfide, five silicone, and two polyether elastomer impression materials were used to compare the accuracy of stone casts reproduced from a master model. The most accurate casts were produced from the polyether rubbers and when the cast pour was delayed for a week, this impression material remained accurate.

Journal ArticleDOI
01 Jun 1974-Chest
TL;DR: It is suggested that ventilation-perfusion studies can: supplement routine spirometry test by giving an estimation of regional lung function, provide an indication of unresectability, occasionally reveal the site of an occult carcinoma of the bronchus.

Journal ArticleDOI
01 Jan 1974-Genetics
TL;DR: The results of breeding experiments with the pink salmon, Oncorhynchus gorbuscha, indicate that s- MDH-A and s-MDH-B subunits are each encoded by duplicate loci.
Abstract: The results of breeding experiments with the pink salmon, Oncorhynchus gorbuscha, indicate that s-MDH-A and s-MDH-B subunits are each encoded by duplicate loci. Limited evidence suggests also that the two loci encoding for the s-MDH-A subunit are each polymorphic and linked or pseudolinked.