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2.
Mol Ecol ; 16(3): 553-68, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17257113

ABSTRACT

The mountain pine beetle Dendroctonus ponderosae is a native species currently experiencing large-scale outbreaks in western North American pine forests. We sought to describe the pattern of genetic variation across the range of this species, to determine whether there were detectable genetic differences between D. ponderosae occupying different host trees in common localities, and to determine whether there was molecular evidence for a past demographic expansion. Using a combination of amplified fragment length polymorphism (AFLP) and mitochondrial sequencing analyses, we found evidence of genetic structuring among populations that followed a broad isolation-by-distance pattern. Our results suggest that the geographical pattern of gene flow follows the core distribution of the principal D. ponderosae host species, around rather than across the Great Basin and Mojave Deserts. Patterns of haplotype diversity and divergence were consistent with a range-wide population expansion. This signal was particularly pronounced in the northern part of the species' range, where outbreak activity is currently increasing. Using AFLP markers, we were unable to detect significant differences among groups of insects sampled from different host trees in common locations. Incidentally, we found that a large proportion of the polymorphic AFLP markers were gender-specific, occurring only in males. While we did not include these markers in our analyses, this finding warrants further investigation.


Subject(s)
Coleoptera/genetics , Genetic Variation , Polymorphism, Genetic , Trees , Animals , Coleoptera/classification , DNA, Mitochondrial/genetics , Female , Geography , Male , Phylogeny , Polymerase Chain Reaction , Sequence Analysis, DNA
3.
Transfusion ; 42(9): 1114-22, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12430666

ABSTRACT

BACKGROUND: Recipient exposure to allogeneic donor WBCs results in transfusion complications for selected populations of recipients. Whether or not WBC reduction should be universally applied is highly controversial. STUDY DESIGN AND METHODS: In a general hospital, a randomized, controlled clinical trial of conversion to universal WBC reduction was conducted. Patients (11%) with established medical indications for WBC-reduced blood were not eligible. All other patients who required transfusion were assigned at random to receive either unmodified blood components or stored WBC-reduced RBCs and platelets. Analysis for each patient was restricted to the first hospitalization. RESULTS: All eligible patients (n = 2780) were enrolled. Three specified primary outcome measures were not different between the two groups: 1) in-hospital mortality (8.5% control; 9.0% WBC-reduced; OR, 0.94 [95% CI, 0.72-1.22]; p = 0.64); 2) hospital length of stay (LOS) after transfusion (median number of days, 6.4 for control and 6.3 for WBC-reduced; p = 0.21); and 3) total hospital costs (median, $19,500 for control and $19,200 for WBC-reduced, p = 0.24). Secondary outcomes (intensive care LOS, postoperative LOS, antibiotic usage, and readmission rate) were not different between the two groups. Subgroup analysis based on patient age, sex, amount of blood transfused, or category of surgical procedure showed no effect of WBC reduction. Patients who received WBC-reduced blood had a lower incidence of febrile reactions (p = 0.06). CONCLUSION: A beneficial effect of conversion from selective to universal WBC reduction was not demonstrated.


Subject(s)
Blood Transfusion/methods , Leukocytes , Adolescent , Adult , Aged , Anti-Bacterial Agents/economics , Anti-Bacterial Agents/therapeutic use , Bacterial Infections/drug therapy , Bacterial Infections/epidemiology , Bacterial Infections/etiology , Bacterial Infections/prevention & control , Blood Component Transfusion/adverse effects , Blood Component Transfusion/economics , Blood Component Transfusion/methods , Blood Component Transfusion/standards , Blood Transfusion/economics , Blood Transfusion/standards , Boston/epidemiology , Child , Child, Preschool , Cost-Benefit Analysis , Drug Utilization/statistics & numerical data , Female , Fever/epidemiology , Fever/etiology , Fever/prevention & control , Hospital Costs , Hospital Mortality , Humans , Incidence , Infant , Length of Stay/statistics & numerical data , Male , Middle Aged , Outcome Assessment, Health Care , Patient Admission/statistics & numerical data , Prospective Studies , Risk Management , Transfusion Reaction
4.
Vox Sang ; 81(3): 172-5, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11703860

ABSTRACT

BACKGROUND AND OBJECTIVES: We compared three methods of isolating platelet-rich plasma (PRP) using the Haemonetics Cell Saver 5 and one method of isolating PRP by plateletpheresis using the Haemonetics MCS+. PRP contains both platelets and fibrinogen, which are used in the preparation of haemostatic agents. MATERIALS AND METHODS: When the Haemonetics Cell Saver 5 was used, 500 ml of blood from each of 30 normal volunteer donors was collected into 70 ml of citrate-phosphate-dextrose (CPD) anticoagulant. In a further 14 normal volunteers, the Haemonetics MCS+ was used to isolate PRP by plateletpheresis using an acid citrate dextrose (ACD) to blood ratio of 1 : 9. In a separate study, CPD-anticoagulated whole blood from another 30 volunteers was used for measurement of fibrinogen levels in the plasma and cryoprecipitate. RESULTS: A larger volume of PRP can be collected using the Haemonetics Cell Saver 5 than by using the Haemonetics MCS+. The platelet concentration and the total number of platelets were higher in the PRP isolated using the Haemonetics MCS+ than in the PRP isolated by the three methods used with the Haemonetics Cell Saver 5, with differences in platelet concentration and PRP volume among the four methods. The mean fibrinogen level in the plasma was 253 mg % +/- 47 (SD) and in the cryoprecipitate was 1085 mg % +/- 304 (SD). CONCLUSIONS: The most appropriate method of PRP isolation for preparation of platelet gel is dependent upon the specific surgical procedure to be undertaken and the patient's needs.


Subject(s)
Blood Transfusion, Autologous/methods , Plasmapheresis/instrumentation , Blood Transfusion, Autologous/instrumentation , Fibrinogen/analysis , Hemostasis, Surgical , Hemostatics/isolation & purification , Humans , Platelet Count , Platelet Transfusion/methods , Platelet Transfusion/standards , Surgical Procedures, Operative
5.
Transfusion ; 41(7): 928-32, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11452162

ABSTRACT

BACKGROUND: The FDA has approved the storage of frozen RBCs at -80 degrees C for 10 years and the postwash storage at 4 degrees C for no more than 24 hours. The 4 degrees C postwash storage period is limited to 24 hours, because the current deglycerolization systems are functionally open systems. STUDY DESIGN AND METHODS: Two units of RBCs were collected from each of 13 healthy male volunteers. The RBCs were collected in CP2D by the FDA-approved protocol for an automated apheresis device (MCS, LN8150, Haemonetics) and were stored at 4 degrees C in AS-3 for 6 days. Using a single disposable glycerolization set in an automated, functionally closed system (ACP 215, Haemonetics) each unit was transferred to a 1000-mL PVC plastic bag and glycerolized to a concentration of 40-percent (wt/vol) glycerol and frozen at -80 degrees C. A single disposable deglycerolization set in the ACP 215 was used to deglycerolize the 2 units from the same donor. The deglycerolized RBCs were stored at 4 degrees C in AS-3 for as long as 21 days. RESULTS: The mean +/- SD freeze-thaw-wash recovery value was 89.4 +/- 3 percent. The residual hemolysis in the RBCs stored at 4 degrees C in AS-3 for 21 days after deglycerolization was 0.9 +/- 0.2 percent, and the units were negative for both aerobic and anaerobic bacteria. The mean Nageotte WBC count was 9 x 10(6) per unit. When the deglycerolized RBCs were given as an autologous transfusion after storage at 4 degrees C in AS-3 for the 7- to 18-day period, the mean +/- SD 24-hour posttransfusion survival was 77 +/- 7 percent, and the index of therapeutic effectiveness was 69 +/- 8 percent. CONCLUSION: Two units of human RBCs collected from a single donor by apheresis in the MCS using an LN8150 set can be glycerolized sequentially with a single disposable set and deglycerolized sequentially with another single disposable set in the ACP 215. The previously frozen RBCs stored in AS-3 for 7 to 18 days at 4 degrees C had acceptable hemolysis and an acceptable mean 24-hour posttransfusion survival value and index of therapeutic effectiveness.


Subject(s)
Adenine , Blood Component Removal , Cryopreservation/methods , Erythrocyte Aging , Erythrocyte Transfusion , Glucose , Glycerol/metabolism , Glycerol/pharmacology , Mannitol , Sodium Chloride , Cell Separation/instrumentation , Freeze Drying/methods , Humans , Time Factors
6.
Transfusion ; 41(7): 933-9, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11452163

ABSTRACT

BACKGROUND: The FDA has approved the storage of frozen RBCs at -80 degrees C for 10 years. After deglycerolization, the RBCs can be stored at 4 degrees C for no more than 24 hours, because open systems are currently being used. Five laboratories have been evaluating an automated, functionally closed system (ACP 215, Haemonetics) for both the glycerolization and deglycerolization processes. STUDY DESIGN AND METHODS: Studies were performed at three military sites and two civilian sites. Each site performed in vitro testing of 20 units of RBCs. In addition, one military site and two civilian sites conducted autologous transfusion studies on ten units of previously frozen, deglycerolized RBCs that had been stored at 4 degrees C in AS-3 for 15 days. At one of the civilian sites, 10 volunteers received autologous transfusions on two occasions in a randomized manner, once with previously frozen RBCs that had been stored at 4 degrees C in AS-3 for 15 days after deglycerolization and once with liquid-preserved RBCs that had been stored at 4 degrees C in AS-1 for 42 days. RESULTS: The mean +/- SD in vitro freeze-thaw-wash recovery value was 87 +/- 5 percent; the mean +/- SD supernatant osmolality on the day of deglycerolization was 297 +/- 5 mOsm per kg of H(2)O, and the mean +/- SD percentage of hemolysis after storage at 4 degrees C in AS-3 for 15 days was 0.60 +/- 0.2 percent. The paired data from the study of 10 persons at the civilian site showed a mean +/- SD 24-hour posttransfusion survival of 76 +/- 6 percent for RBCs that had been stored at 4 degrees C for 15 days after deglycerolization and 72 +/- 5 percent for RBCs stored at 4 degrees C in AS-1 for 42 days. At the three sites at which 24-hour posttransfusion survival values were measured by three double-label procedures, a mean +/- SD 24-hour posttransfusion survival of 77 +/- 9 percent was observed for 36 autologous transfusions to 12 females and 24 males of previously frozen RBCs that had been stored at 4 degrees C in AS-3 for 15 days after deglycerolization. CONCLUSION: The multicenter study showed the acceptable quality of RBCs that were glycerolized and deglycerolized in the automated ACP 215 instrument and stored in AS-3 at 4 degrees C for 15 days.


Subject(s)
Blood Preservation , Cryopreservation , Blood Transfusion, Autologous , Cell Culture Techniques , Cell Separation/instrumentation , Cell Separation/methods , Chromium Radioisotopes , Erythrocytes , Female , Glycerol/metabolism , Glycerol/pharmacology , Humans , Male , Time Factors
7.
Transfusion ; 39(5): 488-91, 1999 May.
Article in English | MEDLINE | ID: mdl-10335998

ABSTRACT

BACKGROUND: The current requirements for the preparation of fresh-frozen plasma within 8 hours of whole-blood collection were designed to maintain clotting factor activities. These requirements, however, limit the production of fresh-frozen plasma in a large blood center. There are few data on the effect of the extension of CPD whole-blood storage to 24 hours on clotting factor activity. STUDY DESIGN AND METHODS: A 500-mL unit of whole blood was collected from 10 volunteer donors. At 1 hour after collection, a plasma sample was separated by centrifugation, and each unit was equally divided into 2 half-units, with 1 half-unit stored at 4 degrees C (range, 1-6 degrees C) and 1 half-unit stored at 22 degrees C (range, 20-24 degrees C) for 8 hours after collection. Each half-unit was then placed at 4 degrees C for further storage for 16 hours. At 8 and 24 hours after collection, plasma samples were separated from each half-unit. All plasma samples were frozen at -18 degrees C. Factors V, VII, VIII, and X; fibrinogen; antithrombin III; protein C; and protein S were measured. RESULTS: No significant changes were noted in factors V, VII, and X; fibrinogen; antithrombin III; protein C; and protein S over the 24-hour storage period. Factor VIII in both half-units was significantly reduced, by 13 percent, from the baseline sample as compared to the level in the 8-hour storage sample (p<0.05). Factor VIII was further reduced by 15 to 20 percent after the 24-hour storage period (p<0.05). CONCLUSION: The coagulation factor activity for all factors measured, with the exception of factor VIII, showed no significant change over the 24-hour storage period. Factor VIII was significantly decreased by 13 percent in 8-hour storage and by an additional 15 to 20 percent in 24-hour storage. For clinical situations not requiring the replacement of factor VIII only, 24-hour frozen plasma has properties comparable to those of fresh-frozen plasma.


Subject(s)
Blood Coagulation Factors , Blood Preservation/methods , Erythrocytes , Plasma , Analysis of Variance , Blood Component Removal , Blood Donors , Humans , Time Factors
8.
Nature ; 396(6710): 482-6, 1998 Dec 03.
Article in English | MEDLINE | ID: mdl-9853758

ABSTRACT

The movement of many transcription factors, kinases and replication factors between the nucleus and cytoplasm is important in regulating their activity. In some cases, phosphorylation of a protein regulates its entry into the nucleus; in others, it causes the protein to be exported to the cytoplasm. The mechanism by which phosphorylation promotes protein export from the nucleus is poorly understood. Here we investigate how the export of the yeast transcription factor Pho4 is regulated in response to changes in phosphate availability. We show that phosphorylation of Pho4 by a nuclear complex of a cyclin with a cyclin-dependent kinase, Pho80-Pho85, triggers its export from the nucleus. We also find that the shuttling receptor used by Pho4 for nuclear export is the importin-beta-family member Msn5, which is required for nuclear export of Pho4 in vivo and binds only to phosphorylated Pho4 in the presence of the GTP-bound form of yeast Ran in vitro. Our results reveal a simple mechanism by which phosphorylation can control the nuclear export of a protein.


Subject(s)
Cell Nucleus/metabolism , DNA-Binding Proteins , Fungal Proteins/metabolism , Receptors, Cytoplasmic and Nuclear/metabolism , Saccharomyces cerevisiae Proteins , Transcription Factors/metabolism , Biological Transport , Cloning, Molecular , Cytoplasm/metabolism , Escherichia coli , GTP Phosphohydrolases/metabolism , Karyopherins , Mutation , Nuclear Proteins/chemistry , Nuclear Proteins/metabolism , Phosphorylation , Protein Binding , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , ran GTP-Binding Protein
10.
Development ; 122(12): 3745-54, 1996 Dec.
Article in English | MEDLINE | ID: mdl-9012496

ABSTRACT

Spatially regulated activation of the Drosophila epidermal growth factor (EGF) receptor by its ligand, Gurken, is required for establishment of the dorsal/ventral axis of the oocyte and embryo. During mid-oogenesis, Gurken is concentrated at the dorsal-anterior of the oocyte and is thought to activate the EGF receptor pathway in adjacent follicle cells. In response to this signal, dorsal follicle cell fate is determined. These cells further differentiate into either appendage-producing or midline cells, resulting in patterning in the dorsal follicle cell layer. We show here that Pointed, an ETS transcription factor, is required in dorsal follicle cells for this patterning. Loss of pointed results in the loss of midline cells and an excess of appendage-forming cells, a phenotype associated with overactivation of the EGF receptor pathway in the dorsal region. Overexpression of pointed leads to a phenotype similar to that generated by loss of the EGF receptor pathway. This suggests that Pointed normally down-regulates EGF receptor signaling in the midline to generate patterning in the dorsal region. Interestingly, pointed expression is induced by the EGF receptor pathway. These data indicate a novel antagonistic function for Pointed in oogenesis; in response to activation of the EGF receptor, pointed is expressed and negatively regulates the EGF receptor pathway, possibly by integrating information from a second pathway.


Subject(s)
Body Patterning/physiology , Drosophila Proteins , ErbB Receptors/metabolism , Oogenesis/physiology , Proto-Oncogene Proteins/metabolism , Transcription Factors/metabolism , Transforming Growth Factor alpha , Animals , DNA-Binding Proteins , Drosophila melanogaster/cytology , Drosophila melanogaster/embryology , Drosophila melanogaster/growth & development , Female , Insect Hormones/metabolism , Models, Biological , Morphogenesis , Nerve Tissue Proteins , Signal Transduction , Tissue Distribution , Transforming Growth Factors/metabolism
11.
Science ; 271(5246): 209-12, 1996 Jan 12.
Article in English | MEDLINE | ID: mdl-8539622

ABSTRACT

PHO4, a transcription factor required for induction of the PHO5 gene in response to phosphate starvation, is phosphorylated by the PHO80-PHO85 cyclin-CDK (cyclin-dependent kinase) complex when yeast are grown in phosphate-rich medium. PHO4 was shown to be concentrated in the nucleus when yeast were starved for phosphate and was predominantly cytoplasmic when yeast were grown in phosphate-rich medium. The sites of phosphorylation on PHO4 were identified, and phosphorylation was shown to be required for full repression of PHO5 transcription when yeast were grown in high phosphate. Thus, phosphorylation of PHO4 by PHO80-PHO85 turns off PHO5 transcription by regulating the nuclear localization of PHO4.


Subject(s)
Cell Nucleus/metabolism , Cyclin-Dependent Kinases/metabolism , Cyclins/metabolism , DNA-Binding Proteins , Fungal Proteins/metabolism , Phosphate Transport Proteins , Repressor Proteins , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae/metabolism , Transcription Factors/metabolism , Amino Acid Sequence , Culture Media , Cytoplasm/metabolism , Dipeptides/metabolism , Gene Expression Regulation, Fungal , Membrane Transport Proteins/genetics , Molecular Sequence Data , Mutation , Phosphates/metabolism , Phosphorylation , Saccharomyces cerevisiae/genetics
12.
Proc Natl Acad Sci U S A ; 92(14): 6557-61, 1995 Jul 03.
Article in English | MEDLINE | ID: mdl-7604032

ABSTRACT

The glass gene is required for proper photo-receptor differentiation during development of the Drosophila eye glass codes for a DNA-binding protein containing five zinc fingers that we show is a transcriptional activator. A comparison of the sequences of the glass genes from two species of Drosophila and a detailed functional domain analysis of the Drosophila melanogaster glass gene reveal that both the DNA-binding domain and the transcriptional-activation domain are highly conserved between the two species. Analysis of the DNA-binding domain of glass indicates that the three carboxyl-terminal zinc fingers alone are necessary and sufficient for DNA binding. We also show that a deletion mutant of glass containing only the DNA-binding domain can behave in a dominant-negative manner both in vivo and in a cell culture assay that measures transcriptional activation.


Subject(s)
DNA-Binding Proteins/biosynthesis , Drosophila Proteins , Drosophila melanogaster/metabolism , Drosophila/metabolism , Transcription Factors/biosynthesis , Zinc Fingers , Amino Acid Sequence , Animals , Base Sequence , Binding Sites , Cell Line , Chloramphenicol O-Acetyltransferase/analysis , Chloramphenicol O-Acetyltransferase/biosynthesis , DNA/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Drosophila/genetics , Drosophila melanogaster/genetics , Eye/ultrastructure , Gene Expression , Genes, Insect , Microscopy, Electron, Scanning , Molecular Sequence Data , Oligodeoxyribonucleotides , Sequence Homology, Amino Acid , Trans-Activators/biosynthesis , Trans-Activators/metabolism , Transcription, Genetic , Transfection
14.
Cell ; 78(1): 137-47, 1994 Jul 15.
Article in English | MEDLINE | ID: mdl-8033205

ABSTRACT

We show that the activities of two Ets-related transcription factors required for normal eye development in Drosophila, pointed and yan, are regulated by the Ras1/MAPK pathway. The pointed gene codes for two related proteins, and we show that one form is a constitutive activator of transcription, while the activity of the other form is stimulated by the Ras1/MAPK pathway. Mutation of the single consensus MAPK phosphorylation site in the second form abrogates this responsiveness. yan is a negative regulator of photoreceptor determination, and genetic data suggest that it acts as an antagonist of Ras1. We demonstrate that yan can repress transcription and that this repression activity is negatively regulated by the Ras1/MAPK signal, most likely through direct phosphorylation of yan by MAPK.


Subject(s)
DNA-Binding Proteins/physiology , Drosophila Proteins , Drosophila/genetics , Extracellular Signal-Regulated MAP Kinases , Eye Proteins/physiology , Proto-Oncogene Proteins/physiology , Repressor Proteins , Signal Transduction/physiology , Transcription Factors/physiology , Animals , Calcium-Calmodulin-Dependent Protein Kinases/genetics , DNA-Binding Proteins/genetics , Eye/growth & development , Eye Proteins/genetics , Gene Expression Regulation , Genes, Insect/genetics , Genes, ras/genetics , Models, Biological , Morphogenesis , Nerve Tissue Proteins , Phenotype , Photoreceptor Cells, Invertebrate/growth & development , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins p21(ras)/genetics , Transcription Factors/genetics , Transcription, Genetic/genetics
16.
Development ; 119(3): 855-65, 1993 Nov.
Article in English | MEDLINE | ID: mdl-8187644

ABSTRACT

The glass gene encodes a DNA-binding zinc-finger protein required for the development of Drosophila photoreceptor cells and which appears to regulate a number of genes specifically expressed in photoreceptors. We have generated monoclonal antibodies to Glass and used them to examine Glass distribution during development. Glass is expressed in all cell types of the developing eye and in all other organs that contain photoreceptor cells in Drosophila, including a small number of cells in the brain. We altered the normal pattern of glass expression by placing the gene under the control of the hsp70 promoter. Our results suggest that nonphotoreceptor cells are restricted in their response to Glass expression. In an effort to discover the mechanism of this restriction, we examined the expression of a number of reporter gene constructs. Our results suggest that nonsensory cells are unable to express certain reporter constructs in response to Glass expression because another DNA-binding factor represses Glass activity in nonsensory cells.


Subject(s)
DNA-Binding Proteins/genetics , Drosophila Proteins , Drosophila/embryology , Eye/embryology , Gene Expression/physiology , Photoreceptor Cells, Invertebrate/embryology , Animals , Base Sequence , DNA Primers , DNA-Binding Proteins/physiology , Drosophila/genetics , Gene Expression Regulation/physiology , Genes, Reporter/physiology , Immunohistochemistry , Molecular Sequence Data
18.
AIDS Res Hum Retroviruses ; 7(12): 991-8, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1667477

ABSTRACT

Recombinant fowlpox viruses (FPV) containing the env or gag-pol genes of simian immunodeficiency virus from macaques (SIVmac) were constructed. The env, gag, and pol-encoded polypeptides were efficiently expressed and processed in avian cells productively infected with FPV as well as in mammalian cells, in which FPV infection is abortive. In addition, the recombinant FPV expressing the gag-pol genes directed the formation of defective, lentivirus-like particles which were released into the culture medium of infected cells. Coinfection of cells with the env and gag-pol recombinant viruses resulted in the generation of particles containing SIVmac envelope glycoprotein. The applications of this system to vaccine development are discussed.


Subject(s)
Fowlpox virus/genetics , Retroviridae Proteins/biosynthesis , Simian Immunodeficiency Virus/genetics , Animals , Base Sequence , Cell Line , Cells, Cultured , Chick Embryo , DNA, Recombinant , Genes, env , Genes, gag , Genes, pol , Genetic Vectors , Microscopy, Electron , Molecular Sequence Data , Promoter Regions, Genetic , Simian Immunodeficiency Virus/growth & development , Simian Immunodeficiency Virus/ultrastructure
19.
Br J Urol ; 66(5): 455-8, 1990 Nov.
Article in English | MEDLINE | ID: mdl-2249110

ABSTRACT

Family screening was offered to the relatives of 57 patients with duplex renal systems and this resulted in the detection of another 37 cases. A further 5 first degree relatives had abnormal intravenous urography, so that 25% of the screened relatives had significant renal abnormalities. It is suggested that there may be a place for screening the whole family if renal tract duplex is detected.


Subject(s)
Family , Kidney/abnormalities , Adult , Female , Genes, Dominant , Humans , Kidney/diagnostic imaging , Male , Pedigree , Radiography
20.
Infect Immun ; 35(2): 476-82, 1982 Feb.
Article in English | MEDLINE | ID: mdl-6276304

ABSTRACT

Strains of Streptococcus ferus isolated from the oral cavities of wild rodents inhabiting sucrose-rich and sucrose-poor environments have many traits in common with the "mutans" streptococci. Thus, S. ferus HD3 and 8S1, like cariogenic S. sobrinus 6715-13, from adherent, alpha (1 leads to 3) glucopyranosyl-glucose linkage-rich, plaquelike deposits in vitro and in vivo through the action of constitutive glucosyltransferase(s) enzymes on sucrose, produce and degrade intracellular polysaccharide, produce short-chain fatty acids from the catabolism of mono- and disaccharides, carry the c antigen of S. mutans, and penetrate, persist, and proliferate in a sucrose-augmented fashion in the oral cavities of specific-pathogen-free rodent caries models. However, unlike infection with common S. mutans, infection with tested S. ferus strains does not cause caries. This avirulence appeared to result more from the reduced aciduricity of S. ferus than from differences in glucosyltransferase complements. Studies showed that despite generally similar growth rates and extracellular glucan syntheses, the acidogenic metabolism of S. ferus was more inhibited by declining environmental pH than was cariogenic S. sobrinus 6715-13 and that, in vitro, less hydroxyapatite was solubilized by S. ferus metabolic end products. The physiology of these S. ferus strains demonstrated that, in addition to plaque formation and acid production, acid tolerance was crucial to the carious process.


Subject(s)
Muridae/microbiology , Streptococcus/physiology , Agglutination , Animals , Dextranase/metabolism , Durapatite , Fructose/metabolism , Glucans/biosynthesis , Glucose/metabolism , Glucosyltransferases/metabolism , Hydrogen-Ion Concentration , Hydroxyapatites/metabolism , Sucrose/metabolism
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