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PubMed1996

Interstrand complex formation of purine oligonucleotides and their nonionic analogs: the model system of d(AG)8 and its complement, d(CT)8.

We have investigated the role of purines in interstrand complex formation with regard to substitution of the negatively-charged, phosphodiester backbone by a nonionic, internucleoside linkage. Using the purine oligomer, d(AG)8, its methylphosphonate analog, d(AG)8, and the complementary pyrimidine oligomer, d(CT)8, as a model system, the stoichiometry, conformation, and stability of complexes formed at pH 8 were studied by spectroscopic and electrophoretic methods. When there is only one oligomer species in solution, d(AG)8 behaves as a single-stranded molecule. In contrast, the d(AG)8 oligomer readily forms an intermolecular self-complex, particularly in the presence of magnesium ion. Using either purine oligomer, duplexes can form with the d(CT)8 strand which differ in terms of their conformation and in the dependence of their thermal stability on sodium and magnesium ions. All studies show that a stable triplex forms with a 1:2 d(CT)8:d(AG)8 stoichiometry which does not require high concentrations of sodium or magnesium ions. Triplex formation between the d(CT)8 strand and two d(AG)8 strands was not observed. Native gel electrophoresis suggests that a 1:1:1 d(CT)8:d(AG)8:d(AG)8 complex may be formed. In regard to triplex formation, the advantage of the methylphosphonate backbone on the purine strand is clearly demonstrated.

Circular Dichroism↗
PubMed1991

Role of viral strains and host genes in determining levels of immune complexes in a model system: implications for HIV infection.

Virus-antibody immune complexes form during infection with most RNA and DNA viruses, including those with human immunodeficiency virus (HIV). Yet a subset of individuals so infected apparently does not mount such responses. To understand the principles involved, we studied the formation and deposition of virus-antibody immune complexes in the circulation in a model system utilizing mice persistently infected with lymphocytic choriomeningitis virus (LCMV). Although mice of several genetic haplotypes could be persistently infected with LCMV, mount anti-LCMV antibody responses, and form immune complexes levels varied among murine strains. Earlier, genetic analysis of high and low immune complex formers, their F1 crosses, and appropriately selected recombinant inbred strains located the ability to mount heightened immune responses in genes within the MHC. Further, variations among LCMV strains in the capacity to incite high levels of immune complex formation were found. Persistent infection with LCMV Armstrong (ARM) strain was associated with high levels of complexes in the circulation and marked deposits in the glomeruli of high-responder SWR/J mice. In contrast, persistent infection of SWR/J mice with LCMV Traub strain led to very low levels of circulating complexes and minimal immune complex deposition in tissues. The amount of virus carried during both infections was roughly equivalent indicating that the genetics of both the host and the virus play essential roles in whether or not immune complexes develop. Antibody responses in SWR/J mice persistently infected with LCMV ARM were 5- to 10-fold higher than responses of age- and sex-matched mice infected with LCMV Traub.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2000

Heteroflocculation of Amidine Polystyrene Latex and Anticarsia gemmatalis Nucleopolyhedrovirus as a Model System for Studying Sunlight Protection.

Anticarsia gemmatalis nucleopolyhedrovirus (AgMNPV) is a baculovirus specific for the control of an important soybean defoliator. The baculovirus is comprised of double-stranded DNA, occluded in a proteinaceous structure called a polyhedron. Ultraviolet sunlight is the most destructive factor that affects the persistence of the virus in the field. In the present study, we use a model system wherein the pathogen is covered by another particle of opposite charge in order to test the effectiveness of a physical barrier as a protection against sunlight. Heteroflocculation experiments were carried out using two different age batches of AgMNPV and amidine polystyrene latex particles. The assessment of heteroflocculation was achieved by zeta potential and adsorption isotherm measurements, and by scanning electron microscopy. Despite the great difference in potentials between latex particles and the baculovirus, low-affinity isotherms were obtained in both pure water and 0.1 mM KCl. Adsorbed latex particles were easily washed out from the polyhedron surface. This low affinity could be attributed to the presence of a strongly repulsive hydration force of short range operating on the system. The results suggest that the failure to obtain a good physical barrier against sunlight might be attributed to the difficulty in keeping the polyhedron surface covered. Copyright 2000 Academic Press.

Journal Article↗
PubMed1995

Biochemical screening of highly toxic aromatic contaminants in river sediment and comparison of sensitivity of biological model systems.

Fractions containing polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) were extracted from river sediments by various extraction methods. The amount of individual pollutants was determined analytically and data compared with biological assays. These were based on the induction of cytochrome P450 1A1 (CYPIA1) after treatment with sediment fractions in two different biological model systems, a mouse hepatoma cell line Hepa-1 and a chick embryo. In the hepatoma cell culture Hepa-1 significant correlations with analytical results were found for fractions containing PCDD/Fs and planar and mono-ortho-chlorinated PCBs. However for PAH fraction an undesirable decrease of P450 1A1 induction was observed in higher concentrations of this fraction. This decrease was not observed in the chick embryo liver microsomes and biological responses towards the PAH fractions correlated with analytical data. Comparative investigations demonstrated that the chicken embryo hepatic microsomes were more sensitive for PAHs, and the hepatoma cell line Hepa-1 for PCDD/Fs and planar and mono-ortho-chlorinated PCBs.

Animals↗
PubMed2003

Ocular neovascularization: a valuable model system.

There is no unique formula for angiogenesis. Instead there is a large group of potential participating proteins that interact in complex ways. Depending upon the surrounding cell types and the relative expression levels of angiogenesis-related proteins, the 'angiogenesis cascade' can vary. Therefore, it is valuable to study and compare the role of proteins in several well-characterized vascular beds. The eye provides a useful model system, because it contains several vascular beds sandwiched between avascular tissue. This allows for unequivocal identification and quantitation of new vessels. Retina-specific promoters combined with inducible promoter systems provide a means to regulate the expression of proteins of interest. As a relatively isolated compartment, the eye also provides advantages for gene transfer. By gaining insight regarding the molecular signals involved in various types of ocular angiogenesis, general concepts can emerge that may apply to other settings, including tumor angiogenesis. One concept that has emerged is that despite participation of multiple stimulatory factors for ocular neovascularization, VEGF plays an essential role and interruption of VEGF signaling is an important therapeutic strategy. Another concept is that while most studies have focused on prevention of ocular neovascularization, regression of new vessels is desirable and is achievable with at least three agents, combretastatin A-4 phosphate, pigment epithelium-derived factor, and angiopoietin-2. Finally, endostatin and angiostatin, which have been sources of controversy because of inconsistent results in tumor models, have been shown to have good efficacy when delivered by gene transfer in models of ocular neovascularization. These results provide leads for new ocular treatments and perspective for evaluation of studies of neovascularization in extraocular tissues.

Angiogenesis Inhibitors↗
PubMed1990

The Betty Neuman Systems Model applied to practice: a client with multiple sclerosis.

The importance of nursing theories and models for the growth and development of the profession of nursing is widely acknowledged. The variety of nursing phenomena and situations demands some flexibility in the choice of specific conceptualizations to be used. This paper demonstrates the goodness of fit of the Betty Neuman Systems Model to the care of clients with multiple sclerosis. An adapted assessment tool, based on Neuman's tool, but more useful in the acute care medical setting, is used to gather data related to a woman with recently diagnosed multiple sclerosis. A nursing care plan illustrating the use of Neuman's model is generated, implemented and evaluated. The Neuman Model is demonstrated to be useful and effective in the implementation of the nursing process in this case.

Adult↗
PubMed2005

Capillary electrophoresis and fluorescence anisotropy for quantitative analysis of peptide-protein interactions using JAK2 and SH2-Bbeta as a model system.

Fluorescence anisotropy capillary electrophoresis (FACE) and affinity probe capillary electrophoresis (APCE) with laser-induced fluorescence detection were evaluated for analysis of peptide-protein interactions with rapid binding kinetics. The Src homology 2 domain of protein SH2-Bbeta (SH2-Bbeta (525-670)) and a tyrosine-phosphorylated peptide corresponding to the binding sequence of JAK2 were used as a model system. For peptide labeled with fluorescein, the K(d) = 82 +/- 7 nM as measured by fluorescence anisotropy (FA). APCE assays had a limit of detection (LOD) of 100 nM or 12 amol injected for SH2-Bbeta (525-670). The separation time of 4 s, achieved using an electric field of 2860 V/cm on 7-cm-long capillaries, was on the same time scale as complex dissociation allowing K(d) (101 +/- 12 nM in good agreement with FA measurements) and dissociation rate (k(off) = 0.95 +/- 0.02 s(-)(1) corresponding to a half-life of 0.73 s) to be determined. This measurement represents a 30-fold higher rate of complex dissociation than what had previously been measurable by nonequilibrium CE analysis of equilibrium mixtures. Using FACE, the protein was detected with an LOD of 300 nM or 7.5 fmol injected. FACE was not used for determining K(d) or k(off); however, this method provided better separation resolution for multiple forms of the protein than APCE. Both methods were found suitable for analysis of cell lysate. These results demonstrate that FACE and APCE may be useful complements to existing techniques for exploring binding interactions with rapid kinetics.

Adaptor Proteins, Signal Transducing↗
PubMed2003

Incidence, risk factors, and outcomes of fecal incontinence after acute brain injury: findings from the Traumatic Brain Injury Model Systems national database.

OBJECTIVE: To investigate the incidence, risk factors, and outcome in patients with fecal incontinence after acute brain injury. DESIGN: A retrospective study of the incidence of and risk factors contributing to fecal incontinence, and outcomes at admission to and discharge from inpatient rehabilitation and at 1-year follow-up. SETTING: Medical centers in the federally sponsored Traumatic Brain Injury Model Systems (TBIMS). PARTICIPANTS: A total of 1,013 consecutively enrolled rehabilitation inpatients from 17 TBIMS centers who were admitted to acute care within 24 hours of traumatic brain injury and seen at 1-year postinjury between 1990 and 2000. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Incidence of fecal incontinence, length of coma, length of posttraumatic amnesia (PTA), admission Glasgow Coma Scale (GCS) score, length of stay (LOS), FIM instrument scores, disposition at discharge and follow-up, and incidences of pelvic fracture, frontal contusion, and urinary tract infection (UTI). RESULTS: The incidence of fecal incontinence was 68% at admission to inpatient rehabilitation, 12.4% at rehabilitation discharge, and 5.2% at 1-year follow-up. Analysis of variance and chi-square analyses revealed statistically significant associations between the incidence of fecal incontinence at rehabilitation admission and admission GCS score, length of coma and PTA, LOS, and incidence of UTI and frontal contusion. Fecal incontinence at rehabilitation discharge was significantly associated with several variables, including age, discharge disposition, admission GCS score, length of coma, PTA, LOS, FIM scores, and incidence of pelvic fracture and frontal contusion. Significant associations were also found between fecal incontinence at 1-year follow-up and age, discharge and current 1-year disposition, admission GCS score, length of coma, LOS, FIM scores, and incidence of UTI (P<.05). Although logistic regression analyses were significant (P<.001), and predicted continence with 100% accuracy, demographics, injury characteristics, medical complications, and functional outcomes did not predict incontinence at discharge and at 1-year follow-up. CONCLUSIONS: Fecal incontinence is a significant problem after brain injury. Certain factors may increase its likelihood. Further studies evaluating mechanisms of fecal incontinence and treatment or control interventions would be useful.

Amnesia↗
PubMed1999

Gas dynamics in CO2 angiography: in vitro evaluation in a circulatory system model.

RATIONALE AND OBJECTIVES: The use of carbon dioxide (CO2) as a vascular contrast agent has increased significantly since the introduction of digital subtraction angiography. To optimize the injection of CO2 for digital subtraction angiography, we evaluated the gas dispersion patterns from differing catheter designs, gas flow dynamics, and the influence of vessel size and inclination on luminal gas filling. METHODS: A circulatory system model was constructed and perfused with 36% glycerin solution at a rate of 1.08 to 1.13 liters per minutes (pulse rate 72 beats/minute, pressure 90-111 mm Hg). Fifty milliliters of CO2 was rapidly injected into the vascular tube of the model (diameter 6.4-15.9 mm) at an inclination of 0 degrees to 45 degrees via a catheter, and imaged digitally in a cross-table lateral projection. The dispersal patterns of gas bubbles from the halo, pigtail, and end-hole catheters were evaluated as well as the degree of luminal gas filling. RESULTS: The halo and end-hole catheters produced continuous gas flow with homogeneous density. The pigtail catheter produced smaller bubbles with inhomogeneous density. Luminal gas filling was incomplete, with a residual fluid level posteriorly regardless of the size and inclination of the tube. At 0 degrees inclination, gas filling was greater with the 6.4-mm tube than with the 15.9-mm tube. With an inclination of 0 degrees to 15 degrees, gas filling was significantly improved for the larger tubes. On dispersal, CO2 bubbles rapidly coalesced and moved forward along the anterior aspect of the tube. The frontal motion of the bubble was parabolic in configuration. CONCLUSIONS: The halo and end-hole catheters provide more homogeneous gas density than the pigtail catheter. Gas filling was incomplete regardless of catheter design, vessel size, or inclination. Inclination improves gas filling in vessels > 12.7 mm in diameter.

Angiography, Digital Subtraction↗
PubMed1994

Radiation checkpoints in model systems.

The response to DNA damaging agents includes a delay to progression through the cell cycle. Irradiation of premitotic cells causes a delay to mitosis and irradiation of G1 and S phase cells causes a delay to DNA synthesis. These delays have become known as checkpoints. The mechanisms that mediate the mitotic (or G2) checkpoint delay have recently come under study in yeast model systems. Work in the eukaryotic organisms S. cerevisiae and S. pombe has identified at least seven proteins controlling the interactions between DNA damage and cell cycle progression. Genetic analysis of this checkpoint pathway has identified substantial overlap with the feedback controls that co-ordinate progression through the cell cycle. Molecular analysis has revealed structural conservation between these highly diverged yeasts, which suggests that similar proteins may act in related pathways in mammalian cells. In addition, the rad24 and rad25 genes of S. pombe (which are involved in the radiation checkpoint) encode functionally overlapping essential proteins that are highly conserved in mammalian cells. Studies of checkpoints in the yeasts may therefore help to define the signal pathways that control cell cycle delay in mammalian cells following irradiation, some of which have been proposed to be deficient in A-T cells.

Amino Acid Sequence↗
PubMed1999

Diarrhea induction by rotavirus NSP4 in the homologous mouse model system.

Comparison of the NSP4 amino acid sequences from 31 strains of mammalian rotaviruses revealed the presence of four distinct NSP4 alleles; i.e., the Wa, KUN, AU-1, and EW alleles. The EW allele consists only of NSP4s from murine rotavirus strains and is divergent from other NSP4 alleles from the evolutionary perspective. There have been conflicting reports regarding the enterotoxigenic activity of NSP4 in the mouse model system; heterologous simian and porcine rotavirus NSP4s function as an enterotoxin in mice, while a homologous EC NSP4 does not play a dominant role as an enterotoxin in the cystic fibrosis conductance regulator knockout mice. To further examine the enterotoxigenic activity of NSP4, we expressed in Escherichia coli a recombinant protein consisting of glutathione S-transferase and amino acid residues 86-175 of the EW NSP4. We found that this fusion protein caused diarrhea in the majority (8/14) of 5- to 6-day-old CD1 mice. This study confirmed and extended that group A rotavirus NSP4s were able to induce diarrhea in neonatal mice and had an enterotoxigenic activity.

Alleles↗
PubMed1993

The photo repair of pyrimidine dimers by DNA photolyase and model systems.

Pyrimidine dimers are eliminated from DNA by a number of different mechanisms known as DNA repair. Photoreactivation, the reversal of the harmful effects of short wavelength radiation by subsequent exposure to longer wavelengths, is one such mechanism. In photoreactivation, the enzyme DNA photolyase utilises light in order to catalyse the cleavage of the cyclobutane ring of the pyrimidine dimer. The results of recent studies of E. coli DNA photolyase and model systems using techniques such as steady state and flash photolysis, time resolved fluorescence and photo CIDNP are surveyed. A mechanism is proposed for the in vitro reaction of E. coli DNA photolyase which involves photoreduction of the FAD radical cofactor followed by electron donation to the dimer from the excited singlet state of reduced FAD.

DNA↗
PubMed1994

DNA replication from initiation zones of mammalian cells in a model system.

We reported that DNA replication initiates from the region containing an autonomously replicating sequence from Saccharomyces cerevisiae when negatively supercoiled plasmid DNA is incubated with the proteins required for simian virus 40 DNA replication (Y. Ishimi and K. Matsumoto, Proc. Natl. Acad. Sci. USA 90:5399-5403, 1993). In this study, the DNAs containing initiation zones from mammalian cells were replicated in this model system. When negatively supercoiled DNA containing an initiation zone (2 kb) upstream of the human c-myc gene was incubated with simian virus 40 T antigen as a DNA helicase, HSSB (also called replication protein A), and DNA polymerase alpha-primase complex isolated from HeLa cells, DNA replication was specifically initiated from the center of the initiation zone, which was elongated bidirectionally in the presence of a DNA swivelase. Without HSSB, the level of DNA synthesis was significantly reduced and the localized initiation could not be detected, indicating that HSSB plays an essential role in the initiation of DNA replication. The digestion of negatively supercoiled template DNA with a single-strand-specific nuclease revealed that HSSB stimulated DNA unwinding in the center of the initiation zone where the DNA duplex is relatively unstable. In contrast, DNA replication started from a broad region of an initiation zone downstream of the dihydrofolate reductase gene from chinese hamster ovary cells, but the center of the region was mapped near the origin of bidirectional DNA replication. These results suggested that this system mimics a fundamental process of initiation of eukaryotic DNA replication. The mechanism of initiation is discussed.

Base Sequence↗
PubMed1993

Alloxan cytotoxicity is highly potentiated by plasma membrane- and lysosomal-associated iron--a study on a model system of cultured J-774 cells.

Pancreatic islet beta cells, and some other cell types, are sensitive to the damaging effects of alloxan. The mechanisms behind the cytotoxicity have not been fully elucidated, although they are considered to be mediated by the formation and effects of reactive oxygen metabolites. In the present study, the cytotoxic effects of alloxan/cysteine at high and low concentrations were investigated on a model system of cultured J-774 cells. Viability was estimated by the trypan blue dye exclusion test, plasma membrane permeability by a modified microfluorometric fluorescein diacetate technique and lysosomal membrane stability by a microfluorometric acridine orange method. The results showed: (a) hydrogen peroxide, readily diffusing through cellular membranes and produced extracellularly in large amounts by alloxan/cysteine at high concentrations, enters the secondary lysosomes if not previously degraded by cellular anti-oxidant systems. Intralysosomal Fenton reactions, with the formation of hydroxyl radicals, may be induced provided catalytically active lysosomal iron is present. This would result in lysosomal membrane damage followed by leakage of lysosomal contents to the cell sap and cell degeneration. (b) Alloxan/cysteine at low concentrations induced production of superoxide and hydrogen peroxide in low amounts which caused almost no lysosomal damage and appeared to be non-toxic unless there was some plasma membrane-associated iron. Consequently, cells initially allowed to endocytose iron during culture, or briefly exposed to iron just before exposure to alloxan and cysteine, showed greatly enhanced sensitivity. In this case iron, in combination with superoxide and hydrogen peroxide, is believed to give rise to plasma membrane-associated hydroxyl radical production (Fenton reaction) with resultant loss of membrane integrity.(ABSTRACT TRUNCATED AT 250 WORDS)

Alloxan↗
PubMed2004

Protective effect of a polyherbal preparation, Brahma rasayana against tumor growth and lung metastasis in rat prostate model system.

Rasayanas are a group of herbal formulations and are used to improve health of the body. Recent studies have demonstrated the immunostimulatory and antioxidant activities of some of these rasayanas and their usefulness in tumor regression. The objective of the study is to evaluate Brahma rasayana for the inhibition of tumor development and prevention of metastasis in vivo using Copenhagen rats and MAT-LyLu cell model system. Copenhagen rats injected with MAT-LyLu cells were treated with Brahma rasayana once daily. This treatment was followed from the second day of cell inoculation until the end of the experiment. The study comprises a comparison of survival time, body weight, tumor incidence, tumor size, tumor weight, histopathological examination of the lung metastasis and serum testosterone levels between rasayana treated and control animals. Brahma rasayana treatment resulted in a 25-37% decrease in palpable tumor incidence, a delay of 1-2 weeks in the tumor occurrence, lower mean tumor volumes, by as much as 14-35% and significant reduction in tumor weight and lung metastasis in comparison to untreated controls. The Ayurvedic poly herbal preparation, Brahma rasayana may play a beneficial role in preventing tumor incidence, tumor growth and metastatic spread. These are inexpensive preparations that have little or no adverse side effects with a potential as lead chemopreventive compounds and which might prove useful for the treatment of disorders such as human prostate cancer.

Animals↗
PubMed1989

Model systems for detecting the hepatic toxicity of pyrrolizidine alkaloids and pyrrolizidine alkaloid N-oxides.

Indicine N-oxide (INO) is a pyrrolizidine alkaloid (PA) with antitumor activity in animals and humans. Prior studies showed that despite the known hepatic toxicity of the PAs, INO did not produce hepatic toxicity in animals but caused unpredictable lethal hepatic toxicity in humans. In this study we have attempted to find a model system for predicting the hepatotoxic potential of antitumor PAs. Primary cultures of rat hepatocytes showed toxicity only with the most hepatotoxic PAs such as lasiocarpine, but did not detect toxicity with other PAs. Subchronic intraperitoneal administration of PAs to weanling rats and adult mice produced, in surviving animals, hepatic megalocytosis and centrilobular necrosis with heliotrine (H) and 9-O-(R(-)-2-(4'-chlorophenyl)-2-hydroxybutyryl)retronecine N-oxide (RC1NO) but only megalocytosis with INO. Thus, despite previous reports, weanling rats offered no advantage over adult mice for detecting significant hepatic toxicity with PAs. Phenobarbital pretreatment of the mice did not increase the hepatic toxicity of any of the PAs. Subchronic oral administration of PAs to adult mice produced hepatic megalocytosis and centrilobular necrosis in surviving animals with H and RC1NO and megalocytosis with INO. Animals that died acutely following oral administration of INO showed hepatic centrilobular necrosis. Administration of several courses of INO intravenously to dogs produced histological evidence of centrilobular hemorrhagic necrosis. It is concluded that there is no single animal model that will predict hepatic toxicity of the type seen in humans with the antitumor PAs. A combination of studies using adult mice and dogs and lethal doses of the PAs offers the best way of detecting potential hepatic toxicity.

Administration, Oral↗
PubMed1989

Rapid partial degradation of DDT by a cytochrome P-450 model system.

Heme compounds, in combination with a reducing agent and oxygen, can express various activities of cytochrome P-450 enzymes. In the present study it was found that a mixture of hemin and excess cysteine was able to degrade the insecticide DDT partially. The major products were three water-soluble, non-toxic conjugates of DDT metabolites with cysteine which had lost two or three of the five chlorine atoms of DDT per molecule and whose structures were elucidated by gas chromatography/mass spectrometry. In 0.05 M NH4HCO3, pH 7.7/ethanol (5:6, by vol.), the degradation reaction catalyzed by the hemin-cysteine model system was at least 8 x 10(4) times faster than the uncatalyzed reaction. In the presence of a designed 24-residues polypeptide or beta-casein, two DDT-binding proteins, an additional fourfold increase in the rate of DDT degradation was observed. Although the concentrations of DDT and cysteine occurring in an organism would be expected to be lower than those in the experiments described, the formation of water-soluble conjugates of DDT metabolites with cysteine (and other amino acids) could also play a role in metabolism and excretion of DDT in vivo.

Binding Sites↗
PubMed2004

Correlation between enzyme activity and substrate storage in a cell culture model system for Gaucher disease.

Gaucher disease, the most common sphingolipidosis, is caused by a decreased activity of glucosylceramide beta-glucosidase, resulting in the accumulation of glucosylceramide in macrophage-derived cells known as Gaucher cells. Much of the storage material is thought to originate from the turnover of cell membranes, such as phagocytosed red and white blood cells. In this study, an in vitro model of Gaucher disease was developed by treating the murine macrophage cell line J774 with a specific inhibitor of glucosylceramide beta-glucosidase, conduritol B-epoxide, and feeding red blood cell ghosts, in order to mimic the disease state. It was found in this model system that glucosylceramide beta-glucosidase activity could be reduced to about 11-15% of the normal control level before increased storage of glucosylceramide occurred. This in vitro system allows insight into the correlation between enzyme activity and lipid storage as predicted by the theory of residual enzyme activity that was proposed by Conzelmann and Sandhoff.

Animals↗