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1.
Digit Health ; 8: 20552076221116774, 2022.
Article in English | MEDLINE | ID: mdl-36034602

ABSTRACT

Introduction: Remote patient monitoring (RPM) is a telehealth activity to collect and analyze patient health or medical data. Its use has expanded in the past decade and has improved medical outcomes and care management of non-communicable chronic diseases. However, implementation of RPM into routine clinical activities has been limited. The objective of this study was to describe the French funding program for RPM (known as ETAPES) and one of the RPM solution providers (Satelia®) dedicated to chronic heart failure (CHF). Methods: A descriptive assessment of both the ETAPES funding program and Satelia® RPM solution was conducted. Data were collected from official legal documents and information that was publicly available online from the French Ministry of Health. Results and Discussion: ETAPES was formally created in 2016 based on previous legislation pertaining to the national health insurance funding strategy. However, it only started to operate in 2018. Patients with CHF were only eligible if they were at medium or high risk of re-hospitalization with a New York Heart Association (NYHA) score superior or equal to two and a BNP>100 pg/ml or NT pro BNP>1000 pg/ml. Medical monitoring was supported through the therapeutic education of a patient on the RPM model of care with a minimum of three training sessions during the first six months. The use of Satelia® Cardio is noteworthy since it relies only on symptomatic monitoring through which the patient manually reports their information by answering a simple questionnaire on a regular basis and does not rely on any connected devices. Conclusion: Innovative funding programs and solutions for RPM need real-world evaluation in the future.

2.
Biochimie ; 88(11): 1673-85, 2006 Nov.
Article in English | MEDLINE | ID: mdl-16584827

ABSTRACT

Saccharomyces cerevisiae has developed several mechanisms to cope with exposure to cadmium. In particular, the sulfur compound glutathione plays a pivotal role in cadmium detoxification, and exposure to cadmium leads to a wide reorganization of S. cerevisiae transcriptome and proteome, resulting in a significant increase in glutathione synthesis. Met4, the transcriptional activator of the sulfur metabolism enzymes, is a critical actor in this reorganization. Recent work has uncovered a part of the mechanism of cadmium-induced Met4 regulation, and showed that it occurs trough the SCF ubiquitin ligase complex SCF(Met30). We discuss this regulation in S. cerevisiae and compare it with the regulation of two other transcriptional activators involved in cadmium detoxification: the Schizosaccharomyces pombe Zip1, regulated by SCF(Pof1), and the mammalian Nrf2, regulated by the SCF-like ubiquitin ligase Cul3:Rbx1:Keap1.


Subject(s)
Cadmium/toxicity , Saccharomyces cerevisiae/enzymology , Schizosaccharomyces/enzymology , Ubiquitin-Protein Ligase Complexes/metabolism , Animals , Glutathione/metabolism , Mammals , Models, Biological , Oxidative Stress/drug effects , Saccharomyces cerevisiae Proteins/metabolism
3.
Mol Microbiol ; 43(4): 1023-37, 2002 Feb.
Article in English | MEDLINE | ID: mdl-11929548

ABSTRACT

The Ccr4-Not complex is a global regulator of transcription that affects genes positively and negatively and is thought to modulate the activity of TFIID. In the present work, we provide evidence that the Ccr4-Not complex may contribute to transcriptional regulation by the Ras/cAMP pathway. Several observations support this model. First, Msn2/4p-dependent transcription, which is known to be under negative control of cAMP-dependent protein kinase (PKA), is derepressed in all ccr4-not mutants. This phenotype is paralleled by specific post-translational modification defects of Msn2p in ccr4-not mutants relative to wild-type cells. Secondly, mutations in various NOT genes result in a synthetic temperature-sensitive growth defect when combined with mutations that compromise cells for PKA activity and at least partially suppress the effects of both a dominant-active RAS2Val-19 allele and loss of Rim15p. Thirdly, Not3p and Not5p, which are modified and subsequently degraded by stress signals that also lead to increased Msn2/4p-dependent activity, show a specific two-hybrid interaction with Tpk2p. Together, our results suggest that the Ccr4-Not complex may function as an effector of the Ras/cAMP pathway that contributes to repress basal, stress- and starvation-induced transcription by Msn2/4p.


Subject(s)
Cyclic AMP/metabolism , DNA-Binding Proteins/metabolism , Fungal Proteins/metabolism , Gene Expression Regulation, Fungal , Ribonucleases/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae/metabolism , Signal Transduction , Transcription Factors/metabolism , ras Proteins/metabolism , Culture Media , Cyclic AMP-Dependent Protein Kinases , DNA-Binding Proteins/genetics , Fungal Proteins/genetics , Glucose/pharmacology , HSP70 Heat-Shock Proteins/genetics , Mutagenesis , Protein Processing, Post-Translational , Ribonucleases/genetics , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae Proteins/genetics , Transcription Factors/genetics
4.
J Biol Chem ; 276(11): 8469-74, 2001 Mar 16.
Article in English | MEDLINE | ID: mdl-11078740

ABSTRACT

Cadmium is very toxic at low concentrations, but the basis for its toxicity is not clearly understood. We analyzed the proteomic response of yeast cells to acute cadmium stress and identified 54 induced and 43 repressed proteins. A striking result is the strong induction of 9 enzymes of the sulfur amino acid biosynthetic pathway. Accordingly, we observed that glutathione synthesis is strongly increased in response to cadmium treatment. Several proteins with antioxidant properties were also induced. The induction of nine proteins is dependent upon the transactivator Yap1p, consistent with the cadmium hypersensitive phenotype of the YAP1-disrupted strain. Most of these proteins are also overexpressed in a strain overexpressing Yap1p, a result that correlates with the cadmium hyper-resistant phenotype of this strain. Two of these Yap1p-dependent proteins, thioredoxin and thioredoxin reductase, play an important role in cadmium tolerance because strains lacking the corresponding genes are hypersensitive to this metal. Altogether, our data indicate that the two cellular thiol redox systems, glutathione and thioredoxin, are essential for cellular defense against cadmium.


Subject(s)
Cadmium/toxicity , Proteome , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae/drug effects , Cysteine/biosynthesis , DNA-Binding Proteins/physiology , Glutathione/biosynthesis , Glutathione/genetics , Oxidative Stress , Saccharomyces cerevisiae/genetics , Thioredoxin Reductase 1 , Thioredoxin-Disulfide Reductase/physiology , Transcription Factors/physiology
5.
J Biol Chem ; 276(10): 7011-6, 2001 Mar 09.
Article in English | MEDLINE | ID: mdl-11084050

ABSTRACT

In an attempt to elucidate the essential function of glutathione in Saccharomyces cerevisiae, we searched for suppressors of the GSH auxotrophy of Deltagsh1, a strain lacking the rate-limiting enzyme of glutathione biosynthesis. We found that specific mutations of PRO2, the second enzyme in proline biosynthesis, permitted the growth of Deltagsh1 in the absence of exogenous GSH. The suppression mechanism by alleles of PRO2 involved the biosynthesis of a trace amount of glutathione. Deletion of PRO1, the first enzyme of the proline biosynthesis pathway, or PRO2 eliminated the suppression, suggesting that gamma-glutamyl phosphate, the product of Pro1 and the physiological substrate of Pro2, is required as an obligate substrate of suppressor alleles of PRO2 for glutathione synthesis. A mutagenesis of a Deltagsh1 strain also lacking the proline pathway failed to generate any suppressor mutants under either aerobic or anaerobic conditions, confirming that glutathione is essential in yeast. This essential function is not related to DNA synthesis based on the terminal phenotype of glutathione-depleted cells or to toxic accumulation of non-native protein disulfides. Analysis of the suppressor strain demonstrates that normal glutathione levels are required for the tolerance to oxidants under acute, but not chronic stress conditions.


Subject(s)
Glutamine/analogs & derivatives , Glutathione/genetics , Glutathione/physiology , Mutation , Proline/biosynthesis , Saccharomyces cerevisiae/genetics , Alleles , Chromatography, Thin Layer , Dose-Response Relationship, Drug , Ethyl Methanesulfonate , Gene Deletion , Gene Library , Glutamine/metabolism , Glutathione/metabolism , Hydrogen Peroxide/pharmacology , Mutagens , Oxidative Stress , Phenotype , Saccharomyces cerevisiae/metabolism , Suppression, Genetic
6.
J Biol Chem ; 274(32): 22586-90, 1999 Aug 06.
Article in English | MEDLINE | ID: mdl-10428837

ABSTRACT

Rpb4p and Rpb7p are two subunits of the yeast RNA polymerase II, which form a subcomplex that can dissociate from the enzyme in vitro. Whereas RPB7 is essential, RPB4 is dispensable for cellular viability. However, the rpb4 null mutant is heat-sensitive, and it has been suggested that Rpb4p is an essential component for cellular stress response. To examine this hypothesis, we used two-dimensional gel electrophoresis to analyze the protein expression pattern of the rpb4 null mutant in response to heat shock, oxidative stress, osmotic stress, and in the post-diauxic phase. We show that this mutant is not impaired in stress induced transcriptional activation: the absence of heat shock response of the mutant is due to a general defect in RNA polymerase II activity at high temperature. Under this condition, Rpb4p is necessary to maintain the polymerase activity in vivo. The heat growth defect of the rpb4 null mutant can be partially suppressed by overexpression of RPB7, suggesting that Rpb4p maintains or stabilizes Rpb7p in the RNA polymerase. We also demonstrate that rpb4 null mutant is an appropriate tool to analyze the involvement of transcriptional events in the survival and adaptation to heat shock or other stresses.


Subject(s)
Heat-Shock Response/physiology , RNA Polymerase II/metabolism , Electrophoresis, Gel, Two-Dimensional , Enzyme Stability , Fungal Proteins/genetics , Fungal Proteins/metabolism , Gene Expression , Hot Temperature , Mutation , Osmotic Pressure , Oxidative Stress/physiology , RNA Polymerase II/genetics , Transcriptional Activation
7.
Mol Microbiol ; 33(2): 274-83, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10411744

ABSTRACT

The heat shock transcription factor Hsf1p and the stress-responsive transcription factors Msn2p and Msn4p are activated by heat shock in the yeast Saccharomyces cerevisiae. Their respective contributions to heat shock protein induction have been analysed by comparison of mutants and wild-type strains using [35S]-methionine labelling and two-dimensional gel electrophoresis. Among 52 proteins induced by a shift from 25 degrees C to 38 degrees C, half of them were found to be dependent upon Msn2p and/or Msn4p (including mostly antioxidants and enzymes involved in carbon metabolism), while the other half (including mostly chaperones and associated proteins) were dependent upon Hsf1p. The two sets of proteins overlapped only slightly. Three proteins were induced independently of these transcription factors, suggesting the involvement of other transcription factor(s). The Ras/cAMP/PKA signalling pathway cAMP had a negative effect on the induction of the Msn2p/Msn4p regulon, but did not affect the Hsf1p regulon. Thus, the two types of transcription factor are regulated differently and control two sets of functionally distinct proteins, suggesting two different physiological roles in the heat shock cellular response.


Subject(s)
DNA-Binding Proteins/genetics , Heat-Shock Proteins/genetics , Hot Temperature , Regulon , Saccharomyces cerevisiae Proteins , Transcription Factors/genetics , Cyclic AMP/metabolism , Cyclic AMP-Dependent Protein Kinases/metabolism , Electrophoresis, Gel, Two-Dimensional , Methionine/metabolism , Saccharomyces cerevisiae/genetics , ras Proteins/metabolism
8.
J Biol Chem ; 274(23): 16040-6, 1999 Jun 04.
Article in English | MEDLINE | ID: mdl-10347154

ABSTRACT

Yap1 and Skn7 are two yeast transcriptional regulators that co-operate to activate thioredoxin (TRX2) and thioredoxin reductase (TRR1) in response to redox stress signals. Although they are both important for resistance to H2O2, only Yap1 is important for cadmium resistance, whereas Skn7 has a negative effect upon this response. The respective roles of Yap1 and Skn7 in the induction of defense genes by H2O2 were analyzed by two-dimensional gel electrophoresis. Yap1 controls a large oxidative stress response regulon of at least 32 proteins. Fifteen of these proteins also require the presence of Skn7 for their induction by H2O2. Although about half of the Yap1 target genes do not contain a consensus Yap1 recognition motif, the control of one such gene, TSA1, involves the binding of Yap1 and Skn7 to its promoter in vitro. The co-operative control of the oxidative stress response by Yap1 and Skn7 delineates two gene subsets. Remarkably, these two gene subsets separate antioxidant scavenging enzymes from the metabolic pathways regenerating the main cellular reducing power, glutathione and NADPH. Such a specialization may explain, at least in part, the dissociated function of Yap1 and Skn7 in H2O2 and cadmium resistance.


Subject(s)
DNA-Binding Proteins/physiology , Fungal Proteins/physiology , Oxidative Stress/genetics , Regulon , Saccharomyces cerevisiae Proteins , Transcription Factors/physiology , DNA, Fungal/metabolism , Electrophoresis, Gel, Two-Dimensional , Eukaryotic Initiation Factor-5 , Hydrogen Peroxide/pharmacology , Peptide Initiation Factors/metabolism , Promoter Regions, Genetic , Saccharomyces cerevisiae
9.
J Biol Chem ; 274(8): 4537-44, 1999 Feb 19.
Article in English | MEDLINE | ID: mdl-9988687

ABSTRACT

To isolate new antioxidant genes, we have searched for activities that would rescue the tert-butyl hydroperoxide (t-BOOH)-hypersensitive phenotype of a Saccharomyces cerevisiae strain deleted for the gene encoding the oxidative stress response regulator Skn7. We report the characterization of AHP1, which encodes a 19-kDa protein similar to the AhpC/TSA protein family within a small region encompassing Cys-62 of Ahp1p and the highly conserved N-terminal catalytic AhpC/TSA cysteine. Ahp1p contains a peroxisomal sorting signal, suggesting a peroxisomal localization. AHP1 exerts strong antioxidant protective functions, as demonstrated both by gene overexpression and deletion analyses, and is inducible by peroxides in an Yap1- and Skn7-dependent manner. Similar to yeast Tsa1p, Ahp1p forms a disulfide-linked homodimer upon oxidation and in vivo requires the presence of the thioredoxin system but not of glutathione to perform its antioxidant protective function. Furthermore, in contrast to Tsa1p, which is specific for H2O2, Ahp1p is specific for organic peroxides. Therefore, with respect to substrate specificity, Ahp1p differs from Tsa1p and is similar to prokaryotic alkyl hydroperoxide reductase AhpC. These data suggest that Ahp1p is a yeast orthologue of prokaryotic AhpC and justifies its name of yeast alkyl hydroperoxide reductase.


Subject(s)
Antioxidants/metabolism , Oxidoreductases/genetics , Peroxidases , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae/genetics , tert-Butylhydroperoxide/toxicity , Amino Acid Sequence , Base Sequence , DNA, Complementary , DNA-Binding Proteins/metabolism , Dimerization , Disulfides/metabolism , Gene Expression Regulation, Fungal , Glutathione/metabolism , Molecular Sequence Data , Oxidoreductases/metabolism , Peroxiredoxins , Saccharomyces cerevisiae/metabolism , Sequence Homology, Amino Acid , Thioredoxins/metabolism , Transcription Factors/metabolism
10.
Mol Pharmacol ; 55(1): 74-82, 1999 Jan.
Article in English | MEDLINE | ID: mdl-9882700

ABSTRACT

The in vivo bioavailability of exogenous fibroblast growth factor 2 (FGF2) was studied after i.v. injection of uniformly 14C-labeled FGF2 into young rats. 14C-FGF2 was rapidly accumulated in almost all solid organs within 5 min. After 30 min, more than 65% of FGF2 was retained in liver, 4.5% in kidneys, 1.2% in spleen, 0.15% in adrenal glands, and trace amounts in bone marrow, eyes, lungs, and heart. Suborgan distribution of 14C-FGF2 showed that for kidneys and adrenal glands, the labeling was mainly concentrated in the cortical zone. Incubation of organ sections with 2 M NaCl or heparin eluted all the radioactivity, indicating that labeling was due to FGF2-heparan sulfate proteoglycan (HSPG) interactions. Electrophoretic analysis show only native 14C-FGF2 in the blood and extracellular matrix; however, FGF2 is continuously catabolized in solid organs, indicating that all participate in the clearance of FGF2 by cellular internalization and subsequent catabolism. All FGF2 catabolic fragments bound heparin, demonstrating the preservation of their HSPG-binding site during the in vivo intracellular catabolism of FGF2. Analysis of the high-affinity receptors of FGF2 (FGFR-1 and FGFR-3) and the mitogen-activated protein kinase did not show any increase in either FGFR tyrosine phosphorylation or in mitogen-activated protein kinase activation. This study shows for the first time that exogenous FGF2 is cleared by HSPG cellular internalization and catabolism without inducing the activation of FGFRs within at least five organs in vivo, which strongly suggests that the HSPG-dependent internalization and catabolism pathway may control the in vivo bioavailability of FGF2.


Subject(s)
Fibroblast Growth Factor 2/pharmacokinetics , Heparan Sulfate Proteoglycans/physiology , Animals , Autoradiography , Biological Availability , Calcium-Calmodulin-Dependent Protein Kinases/metabolism , Carbon Radioisotopes , Male , Phosphorylation , Rats , Rats, Sprague-Dawley , Receptors, Fibroblast Growth Factor/metabolism , Tissue Distribution
11.
J Biol Chem ; 273(35): 22480-9, 1998 Aug 28.
Article in English | MEDLINE | ID: mdl-9712873

ABSTRACT

The changes in gene expression underlying the yeast adaptive stress response to H2O2 were analyzed by comparative two-dimensional gel electrophoresis of total cell proteins. The synthesis of at least 115 proteins is stimulated by H2O2, whereas 52 other proteins are repressed by this treatment. We have identified 71 of the stimulated and 44 of the repressed targets. The kinetics and dose-response parameters of the H2O2 genomic response were also analyzed. Identification of these proteins and their mapping into specific cellular processes give a distinct picture of the way in which yeast cells adapt to oxidative stress. As expected, H2O2-responsive targets include an important number of heat shock proteins and proteins with reactive oxygen intermediate scavenging activities. Exposure to H2O2 also results in a slowdown of protein biosynthetic processes and a stimulation of protein degradation pathways. Finally, the most remarkable result inferred from this study is the resetting of carbohydrate metabolism minutes after the exposure to H2O2. Carbohydrate fluxes are redirected to the regeneration of NADPH at the expense of glycolysis. This study represents the first genome-wide characterization of a H2O2-inducible stimulon in a eukaryote.


Subject(s)
Hydrogen Peroxide/pharmacology , Saccharomyces cerevisiae/drug effects , Electrophoresis, Gel, Two-Dimensional , Fungal Proteins/biosynthesis , Fungal Proteins/genetics , Fungal Proteins/metabolism , Kinetics , Oxidative Stress , RNA, Messenger/genetics , RNA, Messenger/metabolism , Saccharomyces cerevisiae/metabolism
12.
Protist ; 149(1): 39-50, 1998 Feb.
Article in English | MEDLINE | ID: mdl-23196112

ABSTRACT

The major membrane proteins of Paramecium are anchored in the plasma membrane via a glycosylphosphatidylinositol (GPI). The expression of these GPI-proteins, the surface antigen (SAg) and the surface GPI-proteins (SGPs), is temperature-dependent, different sets are expressed at 23°C and at 32 °C. To characterize the GPI-anchor lipid moieties of these proteins, a new strategy of biosynthetic radiolabeling was developed. Cells of Paramecium primaurelia, grown at 23°C or at 32 °C, were fed with [(14)C]-labeled cyanobacteria. The paramecia metabolized the cyanobacteria lipids and synthesized fatty acids with longer and more unsaturated chains. The SAg and SGPs from [(14)C]-labeled paramecia, were purified and the lipid moieties of their GPI-anchors were cleaved by a Bacillus thuringiensis phosphatidylinositol-specific phospholipase C and identified as ceramides. The GPI-anchor ceramides, from the SAg and SGPs expressed at both temperatures, contained long-chain bases which did not display variations detectable upon thin layer chromatography analysis. In contrast, the amide-linked fatty acid component varied: palmitic acid was identified as the major amidelinked fatty acid in the GPI-protein anchors from paramecia grown at 23°C, while at 32°C a C(14) fatty acid could be the prominent fatty acid. This modulation in the fatty acid composition could playa role in the antigenic variation process.

13.
Eur J Biochem ; 249(2): 473-80, 1997 Oct 15.
Article in English | MEDLINE | ID: mdl-9370356

ABSTRACT

Recombinant bovine fibroblast growth factor (FGF2), uniformly labelled with 14C ([14C]FGF2), was purified and showed to be highly stable and to retain full biological activity. Organ distribution of [14C]FGF2 after intravenous injection of young rats was assessed by autoradiography of whole body sections and compared with those obtained with [125I]iodinated FGF2 (125I-FGF2). Thyroid, stomach, intestine, bladder and skin were radioactively labelled only in the case of 125I-FGF2. This tissue-labelling is artefactual, probably due to free iodide binding not observed when using [14C]FGF2. High-resolution autoradiography showed a complex tissue distribution of [14C]FGF2 in kidney and adrenal organs. Incubation of frozen eye sections with [14C]FGF2 showed a specific and high-resolution labelling pattern of ocular tissues. After cellular internalization, [14C]FGF2 was processed into five distinct polypeptides of 16, 14, 8, 7, and 5.5 kDa. The 14-kDa and 7-kDa polypeptides are novel catabolic fragments not detected with radioiodinated FGF2. In terms of stability, tissue distribution specificity, and autoradiographic resolution, [14C]FGF2 proved to have more advantages than 125I-FGF2 for pharmacokinetic and catabolism studies.


Subject(s)
Fibroblast Growth Factor 2/pharmacokinetics , Recombinant Proteins/pharmacokinetics , Adrenal Glands/metabolism , Animals , Aorta , Artifacts , Autoradiography , Biological Transport , Carbon Radioisotopes , Cattle , Cell Division/drug effects , Cells, Cultured , Cloning, Molecular , Endothelium, Vascular/cytology , Endothelium, Vascular/drug effects , Eye/metabolism , Fibroblast Growth Factor 2/administration & dosage , Fibroblast Growth Factor 2/pharmacology , Humans , Injections, Intravenous , Iodine Radioisotopes , Kidney/metabolism , Male , Pigment Epithelium of Eye/cytology , Pigment Epithelium of Eye/drug effects , Rats , Rats, Sprague-Dawley , Recombinant Proteins/administration & dosage , Recombinant Proteins/pharmacology , Time Factors , Tissue Distribution
14.
Electrophoresis ; 17(11): 1683-99, 1996 Nov.
Article in English | MEDLINE | ID: mdl-8982601

ABSTRACT

With the systematic sequencing of the yeast genome, yeast biology has entered a new era where novel challenges have to be faced. One challenge is the identification of the function of the several hundred novel genes discovered by genome sequencing. Another is to understand how all yeast genes act in concert to ensure and maintain cell organization. Two-dimensional (2-D) gel electrophoresis is the technique of choice to take up these challenges because it provides the opportunity of obtaining an overall view of genome expression. In prospect of these studies we have undertaken the construction of a yeast 2-D gel protein database that contains information on polypeptides of the yeast protein map. In this paper we report the information presently contained in this database. The reported information includes the identification of 250 protein spots and the characterization of polypeptides corresponding to N-terminal acetylated proteins, mitochondrial proteins, glucose-repressed proteins, heat shock induced proteins and proteins encoded by intron-containing genes. In all, 600 spots are annotated. These data can be accessed on the Yeast Protein Map server through the World Wide Web network.


Subject(s)
Databases, Factual , Electrophoresis, Gel, Two-Dimensional , Fungal Proteins/chemistry , Saccharomyces cerevisiae/chemistry , Computer Communication Networks , Electrophoresis, Gel, Two-Dimensional/standards , Fungal Proteins/classification , Fungal Proteins/genetics , Gene Expression Regulation, Fungal , Genes, Fungal , Molecular Sequence Data , Reference Standards , Saccharomyces cerevisiae/genetics
15.
J Biol Chem ; 271(17): 10263-70, 1996 Apr 26.
Article in English | MEDLINE | ID: mdl-8626593

ABSTRACT

This work describes a rapid and sensitive technique for the identification of Saccharomyces cerevisiae proteins on two-dimensional gels based on the determination of their amino acid ratios. Specific double labeling with 3H and 14C or 35S-labeled amino acids, chosen among those that are specifically incorporated into proteins without interconversion, allowed an accurate measurement of different amino acid ratios for 200 proteins. A computer program was developed to screen a yeast data base containing 1700 protein sequences and to identify proteins matching the measured Mr, pI, and amino acid ratios. The method, tested with 45 reference proteins, allowed 79 new identifications corresponding to abundant proteins belonging to a few functional families. Some protein spots correspond to homologs of mammalian proteins or to uncharacterized open reading frames. Remarkably, among identified proteins of similar abundance, the organellar proteins have a markedly lower codon usage bias than the cytosolic ones. The double labeling technique is particularly suited to the analysis, on a single two-dimensional gel, of the influence of physiological or genetic changes on yeast protein content.


Subject(s)
Electrophoresis, Gel, Two-Dimensional/methods , Fungal Proteins/isolation & purification , Saccharomyces cerevisiae/chemistry , Amino Acids/metabolism , Carbon Radioisotopes , Cell Compartmentation , Fungal Proteins/metabolism , Isoelectric Point , Molecular Weight , Time Factors , Tritium
16.
Surgery ; 119(2): 141-5, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8571198

ABSTRACT

BACKGROUND: This study was undertaken to compare the efficacy of a novel synthetic material (TMS-1) with polytetrafluoroethylene, polypropylene, and primary closure of experimentally fashioned clean and contaminated abdominal wounds. METHODS: One square centimeter full-thickness abdominal wall defects were created in each of the four abdominal quadrants of anesthetized rats (n = 6). Patches of polytetrafluoroethylene, polypropylene, and a polyurethane-polypropylene composite material (TMS-1) were used to repair three of these defects; the fourth was primarily closed. A second group of rats (n = 9) underwent the same operative protocol; however, peritonitis was induced at the time of operation by using the fecal inoculation technique. Animals were killed 2 to 3 weeks later, and surface area and severity of formed adhesions were assessed. RESULTS: By all methods of assessment, primary closure proved significantly superior to all other methods of closure in clean and contaminated conditions. The three synthetic materials were equally matched for surface area involved in adhesion formation. When compared with the other synthetic materials, TMS-1 was associated with significantly milder adhesions in uninfected (p < 0.002) and in infected (p < 0.002) conditions. CONCLUSIONS: The clear superiority of TMS-1 over other nonabsorbable synthetic materials shown in this pilot study warrants further investigation relative to its use to close large abdominal wall defects.


Subject(s)
Abdominal Muscles/injuries , Abdominal Muscles/surgery , Biocompatible Materials , Animals , Biocompatible Materials/adverse effects , Male , Microscopy, Electron, Scanning , Polypropylenes/adverse effects , Polytetrafluoroethylene/adverse effects , Polyurethanes/adverse effects , Rats , Rats, Sprague-Dawley , Tissue Adhesions/etiology , Wound Infection
17.
Ophthalmic Plast Reconstr Surg ; 11(3): 200-6; discussion 206-8, 1995 Sep.
Article in English | MEDLINE | ID: mdl-8541262

ABSTRACT

An ocular implant designed to simplify surgical implantation, minimize infection and extrusion, and improve motility when used as a prosthetic replacement for eyes removed because of damage or disease was tested in rabbit eyes. The implant consisted of a silicone sphere with patches of porous silicone elastomer at the natural insertion sites of the extraocular muscles. Nine implants also had patch material around the base of an integral post designed to distribute the weight of and transfer motility to an overlying prosthetic conformer. Six implants without posts had a circular porous patch on the central anterior surface to facilitate closure of the conjunctiva and Tenon's capsule. Biocompatibility and feasibility were tested in rabbit eyes for < or = 1 year. The patches promoted conjunctival ingrowth, leading to positional stability, and facilitated adherence of the extraocular muscles. Patch material around the post or on the anterior conjunctival surface enhanced conjunctival closure and healing. All 15 implants were retained with no signs of migration, conjunctival dehiscence, or extrusion. Motility on forced duction testing was significant in all directions. The materials appeared to be biocompatible, and the design with the post provided good motility, with the potential for improved coordinated eye movement as a result of the specifically localized attachment of the extraocular muscles.


Subject(s)
Eye, Artificial , Orbit/surgery , Prostheses and Implants , Silicone Elastomers , Animals , Biocompatible Materials , Conjunctiva/pathology , Eye Enucleation , Eye Movements , Foreign-Body Migration/etiology , Oculomotor Muscles/surgery , Orbit/ultrastructure , Postoperative Complications , Prosthesis Design , Rabbits
18.
Mol Microbiol ; 14(3): 571-81, 1994 Nov.
Article in English | MEDLINE | ID: mdl-7885235

ABSTRACT

Integration of plasmid pCGL320 into a Corynebacterium glutamicum ATCC21086 derivative led to tandem amplification of the inserted plasmid (Labarre et al., 1993). One amplification event was associated with integration of an insertion sequence that we have named IS1206. Hybridizing sequences were only found in C. glutamicum strains and at various copy numbers. IS1206 is 1290 bp long, carries 32 bp imperfect inverted repeats and generates a 3 bp duplication of the target DNA upon insertion. IS1206 presents the features characteristic of the IS3 family and part of the DNA sequence centering on the putative transposase region (orfB) is similar to those of IS3 and some other related elements. Phylogenetic analysis of orfB deduced protein sequences from IS1206 and IS3-related elements contradicts the phylogeny of the species, suggesting that evolution of these elements might be complex. Horizontal transfer could be invoked but other alternatives like ancestral polymorphism or/and different rates of evolution could also be involved.


Subject(s)
Corynebacterium/genetics , DNA Transposable Elements , DNA, Bacterial/genetics , Phylogeny , Amino Acid Sequence , Bacteria/classification , Bacteria/genetics , Base Sequence , Cloning, Molecular , DNA, Bacterial/chemistry , Gene Amplification , Molecular Sequence Data , Nucleic Acid Conformation , Plasmids/genetics , Species Specificity
19.
J Biomed Mater Res ; 28(6): 699-712, 1994 Jun.
Article in English | MEDLINE | ID: mdl-8071381

ABSTRACT

The surgical treatment of pathological myopia involves the placement of a band cut from donor sclera around the back of the globe to provide support and to prevent elongation that leads to retinal detachment and blindness. In the search for a synthetic material that would overcome the disadvantages of the donor tissue band, we tested 11 types of bands made from 14 polymers in rabbit eyes. Bands were cut from porous and solid materials, as well as porous materials coated with solids and solid materials with porous patches affixed to the posterior surface. Criteria for suitability and biocompatibility included ease of placement and suturing, stable positioning, and absence of long-term tissue response on a cellular level. Testing included evaluation by the surgeons performing the implantations, measurement of the distance between the band and the globe, determination of fibrous capsule thickness and amount of collagen deposition, and enumeration of macrophages accumulated at the band/capsule interface. Based on the results of these studies, two of the porous materials (expanded polytetrafluoroethylene and porous polyurethane fabric) and two of the composite materials (porous polyurethane fabric coated with polyacrylonitrile and silicone with microvilli cut into the posterior surface) were selected for further study.


Subject(s)
Biocompatible Materials , Polymers , Prostheses and Implants , Sclera/surgery , Animals , Collagen/metabolism , Humans , Immunohistochemistry , Materials Testing , Microscopy, Electron, Scanning , Myopia/surgery , Rabbits , Sclera/anatomy & histology , Sclera/metabolism
20.
J Ocul Pharmacol ; 10(1): 17-27, 1994.
Article in English | MEDLINE | ID: mdl-8207324

ABSTRACT

For patients with conditions requiring chronic rather than acute therapy, the advantages of collagen shields in providing high and sustained levels of drugs and/or lubricants to the cornea are outweighed by the difficulty of insertion of the shield and the problem of blurred vision. We have developed a delivery system in which collagen pieces suspended in a viscous vehicle can be instilled into the lower forniceal space, thereby simplifying application and reducing blurring of vision. The collagen pieces (Collasomes) can be formulated with various constituents such as antibiotics or cyclosporine, or with chemical alterations such as the inclusion of a lipid (Lacrisomes) for the treatment of dry eyes. In the normal eyes of volunteers, Collasomes hydrated in a solution of sodium fluorescein and suspended in a methylcellulose vehicle as a model for delivery of water-soluble drugs produced fluorescein concentrations 17 to 42 times higher in the cornea and 6 to 8 times higher in the aqueous humor, compared with fluorescein-containing vehicle alone. In a preliminary controlled study, 76% of patients with moderately severe keratoconjunctivitis sicca (KCS) preferred Lacrisomes to the vehicle control because of a more soothing effect and longer duration of comfort. All preparations were well tolerated by all study subjects. Current studies involve improving drug delivery by chemically modifying the collagen molecule to slow diffusion of the drug from the Collasome matrix, as well as varying the amount of cetyl alcohol and combining it with modified collagen in Lacrisomes to maximize comfort in patients with dry eyes.


Subject(s)
Collagen , Drug Delivery Systems , Keratoconjunctivitis Sicca/drug therapy , Ophthalmic Solutions/administration & dosage , Adult , Aged , Aged, 80 and over , Double-Blind Method , Fatty Alcohols/administration & dosage , Female , Humans , Male , Methylcellulose/administration & dosage , Middle Aged
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