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Trujillo FJ, Miller MM, Skogerboe RK, Taylor HE, Grant CL. Ion chromatographic determination of thiosulfate in oil shale leachates. Anal Chem 2002. [DOI: 10.1021/ac00235a054] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Newbound TD, Colsman MR, Miller MM, Wulfsberg GP, Anderson OP, Strauss SH. Dichloromethane is a coordinating solvent. J Am Chem Soc 2002. [DOI: 10.1021/ja00192a052] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Colsman MR, Newbound TD, Marshall LJ, Noirot MD, Miller MM, Wulfsberg GP, Frye JS, Anderson OP, Strauss SH. Silver(I) complexes of dichloromethane and 1,2-dichloroethane. J Am Chem Soc 2002. [DOI: 10.1021/ja00162a040] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Hayman ML, Miller MM, Chandler DM, Goulah CC, Read LK. The trypanosome homolog of human p32 interacts with RBP16 and stimulates its gRNA binding activity. Nucleic Acids Res 2001; 29:5216-25. [PMID: 11812855 PMCID: PMC97595 DOI: 10.1093/nar/29.24.5216] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2001] [Revised: 10/12/2001] [Accepted: 10/22/2001] [Indexed: 11/13/2022] Open
Abstract
RBP16 is a guide RNA (gRNA)-binding protein that was shown through immunoprecipitation experiments to interact with approximately 30% of total gRNAs in Trypanosoma brucei mitochondria. To gain insight into the biochemical function of RBP16, we used affinity chromatography and immunoprecipitation to identify RBP16 protein binding partners. By these methods, RBP16 does not appear to stably interact with the core editing machinery. However, fractionation of mitochondrial extracts on MBP-RBP16 affinity columns consistently isolated proteins of 12, 16, 18 and 22 kDa that were absent from MBP control columns. We describe here our analysis of one RBP16-associated protein, p22. The predicted p22 protein has significant sequence similarity to a family of multimeric, acidic proteins that includes human p32 and Saccharomyces cerevisiae mam33p. Glutaraldehyde crosslinking of recombinant p22 identified homo-multimeric forms of the protein, further substantiating its homology to p32. We confirmed the p22-RBP16 interaction and demonstrated that the two proteins bind each other directly by ELISA utilizing recombinant p22 and RBP16. p32 family members have been reported to modulate viral and cellular pre-mRNA splicing, in some cases by perturbing interaction of their binding partners with RNA. To determine whether p22 similarly affects the gRNA binding properties of RBP16, we titrated recombinant p22 into UV crosslinking assays. These experiments revealed that p22 significantly stimulates the gRNA binding capacity of RBP16. Thus, p22 has the potential to be a regulatory factor in T.brucei mitochondrial gene expression by modulating the RNA binding properties of RBP16.
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Miller MM, Monjan AA, Buckholtz NS. Estrogen replacement therapy for the potential treatment or prevention of Alzheimer's disease. Ann N Y Acad Sci 2001; 949:223-34. [PMID: 11795357 DOI: 10.1111/j.1749-6632.2001.tb04025.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Alzheimer's disease (AD) is an irreversible, progressive brain disorder that occurs gradually and results in memory loss, behavior and personality changes, and a decline in cognitive abilities. Although basic biological data suggest that estrogen may have neuroprotective and neuroenhancing functions, a number of studies have produced conflicting findings on the use of estrogen for maintaining cognitive function in older people. This review summarizes clinical studies that have examined the effects of estrogen in women with AD.
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Merlic CA, Zechman AL, Miller MM. Reactivity of (eta(6)-arene)tricarbonylchromium complexes with carbenoids: arene activation or protection? J Am Chem Soc 2001; 123:11101-2. [PMID: 11686731 DOI: 10.1021/ja011767+] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Miller KE, Miller MM, Jolley MR. Challenges in pain management at the end of life. Am Fam Physician 2001; 64:1227-34. [PMID: 11601805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Effective pain management in the terminally ill patient requires an understanding of pain control strategies. Ongoing assessment of pain is crucial and can be accomplished using various forms and scales. It is also important to determine if the pain is nociceptive (somatic or visceral pain) or neuropathic (continuous dysesthesias or chronic lancinating or paroxysmal pain). Nociceptive pain can usually be controlled with nonsteroidal antiinflammatory drugs or corticosteroids, whereas neuropathic pain responds to tricyclic antidepressants or anticonvulsants. Relief of breakthrough pain requires the administration of an immediate-release analgesic medication. If a significant amount of medication for breakthrough pain is already being given, the baseline dose of sustained-release analgesic medication should be increased. If pain does not respond to one analgesic medication, physicians should use an equianalgesic dose chart when changing the medication or route of administration. Opioid rotation can be used if pain can no longer be controlled on a specific regimen. The impact of unresolved psychosocial or spiritual issues on pain management may need to be addressed.
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Merlic CA, Miller MM, Hietbrink BN, Houk KN. Reactivity of (eta(6)-arene)tricarbonylchromium complexes toward additions of anions, cations, and radicals. J Am Chem Soc 2001; 123:4904-18. [PMID: 11457317 DOI: 10.1021/ja000600y] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A computational and experimental study of additions of electrophiles, nucleophiles, and radicals to tricarbonylchromium-complexed arenes is reported. Competition between addition to a complexed arene and addition to a noncomplexed arene was tested using 1,1-dideuterio-1-iodo-2-((phenyl)tricarbonylchromium)-2-phenylethane. Reactions under anionic and cationic conditions give exclusive formation of 1,1-dideuterio-1-((phenyl)tricarbonylchromium)-2-phenylethane arising from addition to the complexed arene. Radical conditions (SmI(2)) afford two isomeric products, reflecting a 2:1 preference for radical addition to the noncomplexed arene. In contrast, intermolecular radical addition competition experiments employing ketyl radical addition to benzene and (benzene)tricarbonylchromium show that addition to the complexed aromatic ring is faster than attack on the noncomplexed species by a factor of at least 100,000. Density functional theory calculations using the B3LYP method, employing a LANL2DZ basis set for geometry optimizations and a DZVP2+ basis set for energy calculations, for all three reactive intermediates showed that tricarbonylchromium stabilizes all three types of intermediates. The computational results for anionic addition agree well with established chemistry and provide structural and energetic details as reference points for comparison with the other reactive intermediates. Intermolecular radical addition leads to exclusive reaction on the complexed arene ring as predicted by the computations. The intramolecular radical reaction involves initial addition to the complexed arene ring followed by an equilibrium leading to the observed product distribution due to a high-energy barrier for homolytic cleavage of an exo bond in the intermediate cyclohexadienyl radical complex. Mechanisms are explored for electrophilic addition to complexed arenes. The calculations strongly favor a pathway in which the cation initially adds to the metal center rather than to the arene ring.
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Hunt HD, Lupiani B, Miller MM, Gimeno I, Lee LF, Parcells MS. Marek's disease virus down-regulates surface expression of MHC (B Complex) Class I (BF) glycoproteins during active but not latent infection of chicken cells. Virology 2001; 282:198-205. [PMID: 11259202 DOI: 10.1006/viro.2000.0797] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Infection of chicken cells with three Marek's disease virus (MDV) serotypes interferes with expression of the major histocompatibility complex (MHC or B complex) class I (BF) glycoproteins. BF surface expression is blocked after infection of OU2 cells with MDV serotypes 1, 2, and 3. MDV-induced T-cell tumors suffer a nearly complete loss of cell surface BF upon virus reactivation with 5-bromo-2'-deoxyuridine (BUdR). The recombinant virus (RB1BUS2gfpDelta) transforming the MDCC-UA04 cell line expresses green fluorescent protein (GFP) during the immediate early phase of viral gene expression. Of the UA04 cells induced to express the immediate early GFP, approximately 60% have reduced levels of BF expression. All of the reactivated UA04 and MSB1 tumor cells expressing the major early viral protein pp38 display reduced levels of BF. Thus, BF down-regulation begins in the immediate early phase and is complete by the early phase of viral gene expression. The intracellular pool of BF is not appreciably affected, indicating that the likely mechanism is a block in BF transport and not the result of transcriptional or translational regulation.
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Afanassieff M, Goto RM, Ha J, Sherman MA, Zhong L, Auffray C, Coudert F, Zoorob R, Miller MM. At least one class I gene in restriction fragment pattern-Y (Rfp-Y), the second MHC gene cluster in the chicken, is transcribed, polymorphic, and shows divergent specialization in antigen binding region. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:3324-33. [PMID: 11207288 DOI: 10.4049/jimmunol.166.5.3324] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
MHC genes in the chicken are arranged into two genetically independent clusters located on the same chromosome. These are the classical B: system and restriction fragment pattern-Y (Rfp-Y), a second cluster of MHC genes identified recently through DNA hybridization. Because small numbers of MHC class I and class II genes are present in both B: and Rfp-Y, the two clusters might be the result of duplication of an entire chromosomal segment. We subcloned, sequenced, and analyzed the expression of two class I loci mapping to Rfp-Y to determine whether Rfp-Y should be considered either as a second, classical MHC or as a region containing specialized MHC-like genes, such as class Ib genes. The Rfp-Y genes are highly similar to each other (93%) and to classical class Ia genes (73% with chicken B: class I; 49% with HLA-A). One locus is disrupted and unexpressed. The other, YFV, is widely transcribed and polymorphic. Mature YFV protein associated with beta(2)m arrives on the surface of chicken B (RP9) lymphoma cells expressing YFV as an epitope-tagged transgene. Substitutions in the YFV Ag-binding region (ABR) occur at four of the eight highly conserved residues that are essential for binding of peptide-Ag in the class Ia molecules. Therefore, it is unlikely that Ag is bound in the YFV ABR in the manner typical of class Ia molecules. This ABR specialization indicates that even though YFV is polymorphic and widely transcribed, it is, in fact, a class Ib gene, and Rfp-Y is a region containing MHC genes of specialized function.
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Delany ME, Krupkin AB, Miller MM. Organization of telomere sequences in birds: evidence for arrays of extreme length and for in vivo shortening. CYTOGENETICS AND CELL GENETICS 2001; 90:139-45. [PMID: 11060464 DOI: 10.1159/000015649] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Telomeres are the specialized ends of chromosomes consisting of highly conserved repeat (5'-TTAGGG-3')(n) sequences. Lack of information regarding the existence of an in vivo telomere clock function in birds, conflicting data regarding telomere array length in the chicken model, and the paucity of molecular telomere information for other avian species led us to study telomere array organization within and among 18 species and subspecies of birds. Most of the species contained between 2% and 4% telomere sequence per diploid genome. Arrays spanning 0.5-10 kb (Class I) and 10-40 kb (Class II) were observed in all of the species studied. Extremely long arrays, ranging from hundreds of kilobases to 1-2 Mb (Class III) were observed in all except two raptor species, the northern goshawk and American bald eagle. In chicken, there was evidence for shortening of the Class II arrays in vivo, based on intraindividual comparisons of somatic versus germline tissues in birds of different ages; terminally differentiated erythrocyte arrays were, on average, 2.3 kb shorter than sperm (germline) arrays. This study provides the first evidence for the existence of telomere arrays significantly larger than have been described for any vertebrate species to date and for developmentally programmed in vivo telomere shortening in the Aves taxa. The novel finding of megabase-sized telomere arrays may be an important feature of avian karyotypes that contain a large number of very small genetic units, the microchromosomes.
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LePage KT, Miller MM, Briles WE, Taylor RL. Rfp-Y genotype affects the fate of Rous sarcomas in B2B5 chickens. Immunogenetics 2000; 51:751-4. [PMID: 10941848 DOI: 10.1007/s002510000180] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Pelletier M, Miller MM, Read LK. RNA-binding properties of the mitochondrial Y-box protein RBP16. Nucleic Acids Res 2000; 28:1266-75. [PMID: 10666472 PMCID: PMC102606 DOI: 10.1093/nar/28.5.1266] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have previously identified a mitochondrial Y-box protein in Trypanosoma brucei that we designated RBP16. The predicted RBP16 amino acid sequence revealed the presence of a cold-shock domain at its N-terminus and a glycine- and arginine-rich C-terminus reminiscent of an RGG RNA-binding motif. Since RBP16 is capable of interacting with different guide RNAs (gRNAs) in vitro and in vivo primarily via the oligo(U) tail, as well as with ribosomal RNAs, possible functions of RBP16 may be in kinetoplastid RNA editing and/or translation. Herein, we report experiments that further define the RNA-binding properties of RBP16. RBP16 forms a single stable complex with the gRNA gA6[14] at low protein concentration, while at higher protein concentration two stable complexes that possibly represent two different conformations are observed. Both complexes are stable at relatively high salt and moderate heparin concentrations indicating that the binding of RBP16 to gA6[14] does not rely primarily on ionic interactions. Phenylglyoxal treatment of the protein indicates that arginine residues are important in RNA binding. The minimal length of RNA sequence necessary for the binding of RBP16 was assessed by gel retardation and UV cross-linking competition assays using oligo(U) ribonucleotides of varying lengths (4-40 nt). Although RBP16 can bind to oligonucleotides as small as U(4), its affinity increases with the length of the oligo(U) ribonucleotide, with a dramatic increase in binding efficiency observed when the length is increased to 10 nt. Gel retardation assays employing T.brucei mRNAs demonstrated that, although it acts as a major binding determinant, a 3' U tail is not an absolute requirement for efficient RBP16-RNA binding. Experiments with oligonucleotides containing U stretches embedded at different positions in oligo(dC) indicated that high-affinity binding requires both a uridine stretch, as well as 5' and 3' non-specific sequences. These results suggest a model for the molecular interactions involved in RBP16-RNA binding.
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Edelstein RL, Tamanaha CR, Sheehan PE, Miller MM, Baselt DR, Whitman LJ, Colton RJ. The BARC biosensor applied to the detection of biological warfare agents. Biosens Bioelectron 2000; 14:805-13. [PMID: 10945455 DOI: 10.1016/s0956-5663(99)00054-8] [Citation(s) in RCA: 351] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The Bead ARray Counter (BARC) is a multi-analyte biosensor that uses DNA hybridization, magnetic microbeads, and giant magnetoresistive (GMR) sensors to detect and identify biological warfare agents. The current prototype is a table-top instrument consisting of a microfabricated chip (solid substrate) with an array of GMR sensors, a chip carrier board with electronics for lock-in detection, a fluidics cell and cartridge, and an electromagnet. DNA probes are patterned onto the solid substrate chip directly above the GMR sensors, and sample analyte containing complementary DNA hybridizes with the probes on the surface. Labeled, micron-sized magnetic beads are then injected that specifically bind to the sample DNA. A magnetic field is applied, removing any beads that are not specifically bound to the surface. The beads remaining on the surface are detected by the GMR sensors, and the intensity and location of the signal indicate the concentration and identity of pathogens present in the sample. The current BARC chip contains a 64-element sensor array, however, with recent advances in magnetoresistive technology, chips with millions of these GMR sensors will soon be commercially available, allowing simultaneous detection of thousands of analytes. Because each GMR sensor is capable of detecting a single magnetic bead, in theory, the BARC biosensor should be able to detect the presence of a single analyte molecule.
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Abstract
Women are being presented with an increasing number of choices for health care management as they move through the aging process. Estrogen has positive effects on mood, sexual function, target end organs and cognitive function, and may play an important role in the etiology of Alzheimer's Disease by acting to prevent amyloid plaque formation, oxidative stress, or deterioration of the cholinergic neurotransmitter system. The benefits of estrogen therapy for osteoporosis, the cardiovascular system, and lipid metabolism are far reaching, but the possibility of developing breast cancer later in life is also relevant. Understanding the mechanisms for the action of the estrogens, anti-estrogens, and the selective estrogen receptor modulators, and possible alternative routes of symptom management for some menopausal events is important to make appropriate decisions on choice of therapy. This review discusses the theoretical basis for estrogen's actions in the management of the postmenopausal stage of the life cycle.
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Miller MM, Hyder SM, Assayag R, Panarella SR, Tousignant P, Franklin KB. Estrogen modulates spontaneous alternation and the cholinergic phenotype in the basal forebrain. Neuroscience 1999; 91:1143-53. [PMID: 10391490 DOI: 10.1016/s0306-4522(98)00690-3] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We report that a small population of neurons expresses both choline acetyltransferase and classical estrogen receptor immunoreactivity and they are found primarily in the bed nucleus of the stria terminalis. In short-term ovariectomized ageing mice (24 months, n = 5) there were 41.0 +/- 4.1% fewer of these double-labeled cells than in young (five months, n = 5) short-term ovariectomized C57BL/6J mice. To study cholinergic neuron estrogen responsiveness, young mice (n = 8) were ovariectomized at puberty (five weeks). After three months half of the mice (n = 4) were given physiological levels of 17beta estradiol for 10 days. Bed nucleus double-labeled neurons increased by 32.9% (P < or = 0.003) in the young mice given estrogen. In a gel shift assay, double-stranded oligonucleotides with putative estrogen response elements from the choline acetyltransferase gene were used as competitors against estrogen receptor binding to consensus estrogen response elements. A sequence with 60% homology to the vitellogenin estrogen response element was found to compete at 500- and 1000-fold excess. Young mice (five months) with ovaries demonstrated significantly (P < or = 0.04) better performance in the spontaneous alternation T-maze test than did old (19 month) mice with ovaries (young = 66.3 +/- 3.3% correct choices; vs old = 55.0 +/- 4.0% in old mice with ovaries). Young mice (five months old), ovariectomized for one month and treated with estrogen, showed significantly more spontaneous alternation than ovariectomized controls (69.1 +/- 2.8% vs 58.3 +/- 3.9%; P < or = 0.04). Estrogen also increased spontaneous alternation in old, short-term ovariectomized mice (61.5 +/- 2.7% vs 48 +/- 3.3%; P < or = 0.005). In either young or old ovariectomized mice, estrogen increased spontaneous alternation to levels seen in young animals with ovaries. Estrogen increases the number of choline acetyltransferase-immunoreactive and choline acetyltransferase/estrogen receptor-immunoreactive cells in old or young mice lacking estrogen, and enhances working memory in old or young mice lacking estrogen. Our data suggest that estrogen may act at the level of the choline acetyltransferase gene, but in view of the limited distribution of cholinergic cells expressing the classical estrogen receptor, it is unlikely that these cells can account for a memory enhancing effect of estrogen replacement.
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Miller MM, Sweeney CR, Russell GE, Sheetz RM, Morrow JK. Effects of blood contamination of cerebrospinal fluid on western blot analysis for detection of antibodies against Sarcocystis neurona and on albumin quotient and immunoglobulin G index in horses. J Am Vet Med Assoc 1999; 215:67-71. [PMID: 10397068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
OBJECTIVE To determine effects of blood contamination on western blot (WB) analysis of CSF samples for detection of anti-Sarcocystis neurona antibodies, and on CSF albumin and IgG concentrations, albumin quotient (AQ), and IgG index in horses. DESIGN Prospective in vitro study. SAMPLES Blood with various degrees of immunoreactivity against S neurona was collected from 12 healthy horses. Cerebrospinal fluid without immunoreactivity against S neurona was harvested from 4 recently euthanatized horses. PROCEDURE Blood was serially diluted with pooled nonimmunoreactive CSF so that final dilutions corresponded to 10(-3) to 100 microliters of blood/ml CSF, and WB analysis was performed on contaminated CSF samples. Number of RBC, albumin and IgG concentrations, AQ, and IgG index were also determined. RESULTS Antibodies against S neurona were detected in CSF contaminated with 10(-3) microliters of strongly immunoreactive blood/ml. In CSF samples contaminated with 10 microliters of blood/ml, AQ remained within reference range. Volume of blood required to increase IgG index varied among blood samples and was primarily influenced by serum IgG concentrations. Number of RBC in contaminated samples was correlated with volume of blood added, but not with degree of immunoreactivity detected in contaminated CSF samples. CONCLUSIONS AND CLINICAL RELEVANCE During collection of CSF from horses, contamination with blood may introduce serum antibodies against S neurona at concentrations sufficient for detection by WB analysis, thus yielding false-positive results. When blood is moderately or strongly immunoreactive, the amount of contaminating albumin may be small enough as to not increase AQ above reference range. In these cases, AQ and IgG index should be interpreted with caution.
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Henry J, Miller MM, Pontarotti P. Structure and evolution of the extended B7 family. IMMUNOLOGY TODAY 1999; 20:285-8. [PMID: 10354554 DOI: 10.1016/s0167-5699(98)01418-2] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Here, Joëlle Henry and colleagues explore structural and evolutionary relationships between the B7 costimulator molecules and a growing number of molecules encoded within the major histocompatibility complex. They propose that B7 and MHC genes are derived from a common ancestor, with several members of this large gene family possibly having pivotal influences on T-cell activation.
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Jarvi SI, Goto RM, Gee GF, Briles WE, Miller MM. Identification, inheritance, and linkage of B-G-like and MHC class I genes in cranes. J Hered 1999; 90:152-9. [PMID: 9987924 DOI: 10.1093/jhered/90.1.152] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We identified B-G-like genes in the whooping and Florida sandhill cranes and linked them to the major histocompatibility complex (MHC). We evaluated the inheritance of B-G-like genes in families of whooping and Florida sandhill cranes using restriction fragment patterns (RFPs). Two B-G-like genes, designated wcbg1 and wcbg2, were located within 8 kb of one another. The fully sequenced wcbg2 gene encodes a B-G IgV-like domain, an additional Ig-like domain, a transmembrane domain, and a single heptad domain typical of alpha-helical coiled coils. Patterns of restriction fragments in DNA from the whooping crane and from a number of other species indicate that the B-G-like gene families of cranes are large with diverse sequences. Segregation of RFPs in families of Florida sandhill cranes provide evidence for genetic polymorphism in the B-G-like genes. The restriction fragments generally segregated in concert with MHC haplotypes assigned by serological typing and by single stranded conformational polymorphism (SSCP) assays based in the second exon of the crane MHC class I genes. This study supports the concept of a long-term association of polymorphic B-G-like genes with the MHC. It also establishes SSCP as a means for evaluating MHC genetic variability in cranes.
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Miller MM, Bennett HP, Billiar RB, Franklin KB, Joshi D. Estrogen, the ovary, and neutotransmitters: factors associated with aging. Exp Gerontol 1998; 33:729-57. [PMID: 9951619 DOI: 10.1016/s0531-5565(98)00018-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Our studies in the C57BL/6J mouse have been designed to examine the interactions of aging and the ovary, and their mutual effects on neuroendocrine function. In the pituitary, ovarian status and not age determines responsiveness to gonadotropin hormone releasing hormone (GnRH), but estrogen (E2) is an important mediator in CNS changes, and removal of the ovary (OVX) is deleterious to the neuroendocrine hypothalamus. OVX for just six days in young animals results in synaptic loss between noradrenergic terminals and gonadotropin hormone releasing hormone (GnRH) neurons. Long-term OVX, hypothesized to protect against neuroendocrine aging, fails to guard against any studied age-related changes. Some age-related changes occur as early as midlife. Although neuron number remains constant at middle age, opiatergic neurons undergo significant functional changes by producing opiate antagonist peptides. This change appears to be caused by alterations in the prohormone convertases, which cleave propeptide to peptide. Altered peptides may trigger the loss of reproductive capacity. The midlife shift in opiate peptide production is a component of natural developmental processes that begin in the neonate and continue through old age. In the cholinergic system, E2 mediates numbers of cholinergic receptors, cholinergic neurons, and cholinergic-modulated memory systems in both young and old animals. Regardless of age, ovarian steroids, if present at physiologic levels, are beneficial to the neuroendocrine CNS, and long-term deprivation from ovarian-produced factors is deleterious in the systems we have examined. Our studies have shown that deprivation from ovarian steroid hormones in the female appears to be a major factor in the health of the CNS and in events associated with aging.
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Griess GA, Guiseley KB, Miller MM, Harris RA, Serwer P. The formation of small-pore gels by an electrically charged agarose derivative. J Struct Biol 1998; 123:134-42. [PMID: 9843667 DOI: 10.1006/jsbi.1998.4021] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous studies have shown that, during the formation of an underivatized agarose gel, agarose molecules laterally aggregate to form thicker fibers called suprafibers; the suprafibers branch to form a gelled network. In the present study, electron microscopy of thin sections is used to investigate both the thickness and the spacing of the fibers of gels formed by agarose chemically derivatized with carboxymethyl (negatively charged) groups. For carboxymethyl agarose, electron microscopy reveals that gels cast in water consist of both fibers narrower and pores smaller than those observed for water-cast underivatized agarose gels at the same concentration. This result is confirmed by using the electrophoretic sieving of spheres to determine the radius (PE) of the effective pore of the gel. At a given concentration of gel less than 1%, the PE for a water-cast carboxymethyl agarose gel is 0.25-0.30x the PE for a water-cast underivatized agarose gel. The value of PE predicts the extent of the electrophoretic sieving that is observed when double-stranded DNA is subjected to electrophoresis through a water-cast carboxymethyl agarose gel; DNA bands formed in a water-cast carboxymethyl agarose gel are comparable in quality to DNA bands formed in a water-cast underivatized agarose gel of equal PE. The following observation supports the hypothesis that electrical charge-charge repulsion among carboxymethyl agarose molecules inhibits the formation of suprafibers in water-cast carboxymethyl agarose gels: Increased content of suprafibers in carboxymethyl agarose gels is observed when the ionic strength is raised by the presence of NaCl, MgCl2, or any of several buffers during gelation of carboxymethyl agarose.
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Mahadevan MM, Miller MM, Maris MO, Moutos D. Assisted hatching of embryos by micromanipulation for human in vitro fertilization: UAMS experience. THE JOURNAL OF THE ARKANSAS MEDICAL SOCIETY 1998; 94:529-31. [PMID: 9604584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In vitro fertilization and embryo transfer (IVF) is utilized as a treatment for infertile couples who cannot conceive with standard therapy. Assisted hatching (AH) is a procedure whereby an opening is made in the zona pellucida of the embryos, thereby increasing the probability of implantation and pregnancy. AH is beneficial in patients with elevated FSH levels, older than age 38 or those who failed IVF repeatedly. Success rates after IVF with AH at the University of Arkansas for Medical Sciences (UAMS) compares favorably with rates achieved by other centers in the USA. Pregnancy rates after IVF with AH in patients older than 38 years is approximately 20% compared to a pregnancy rate of 10% in patients who did not have AH. This report summarizes the UAMS experience with IVF and AH.
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Mahadevan MM, McIntosh Q, Miller MM, Breckinridge SM, Maris M, Moutos DM. Formaldehyde in cryoprotectant propanediol and effect on mouse zygotes. Hum Reprod 1998; 13:979-82. [PMID: 9619557 DOI: 10.1093/humrep/13.4.979] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Cryopreservation of human zygotes and embryos has been routinely performed by in-vitro fertilization clinics for many years. Karran and Legge (1996) first reported that formaldehyde (FA) present in the cryoprotective solutions can have a deleterious effect on mouse oocytes. FA is a cytotoxic, carcinogenic and mutagenic chemical. The effect of FA on mouse zygotes was investigated. In addition, the concentrations of FA in propanediol (PROH) obtained from various sources were determined. Pooled 1-cell embryos were dispensed into droplets of modified Ham's F10 or human tubal fluid containing various concentrations of FA. Since bovine serum albumin (BSA) may minimize toxicity additional trials were done as above in the absence of BSA. FA concentration in the standard 1.5 M PROH, from different sources in water, was measured in the same assay using a standard curve of 0-100 microM FA. FA in a complex medium had a significant deleterious effect on embryo development and hatching but only at 1 mM concentration (P < 0.000001; see Tables I-III). There was no significant effect of FA at 100 microM. However, in a simple medium even 50 microM FA decreased embryo hatching. FA was present in 1.5 M PROH from different sources (range 1.0-35.3 microM concentration). It appears that FA concentrations do not increase with storage because FA concentrations were low even after opening and storage for 3 years on the shelf. This suggests that FA is a contaminant during the manufacturing process and may vary from manufacturer to manufacturer and batch to batch. Until further studies are done to confirm the lack of toxicity to embryos during cryopreservation (with or without FA scavengers) it may be prudent to screen all batches of cryoprotectants for FA as part of quality control.
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Miller MM, Marr C. The use of "diagnostic V codes" in pediatric ophthalmology. J AAPOS 1998; 2:91-3. [PMID: 10530969 DOI: 10.1016/s1091-8531(98)90070-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND Children requiring comprehensive eye examination for signs of familial eye disease or suspected systemic condition are referred to pediatric ophthalmologists. Such examinations may be critical to diagnosis and patient management, yet medically necessary screening examinations are not reimbursed by insurers when the patient is "normal." Faced with this dilemma regularly in a children's hospital practice, we began tracking insurer acceptance of "diagnostic V codes," which are diagnostic codes generally related to symptoms or status conditions rather than to medical states. The authors felt that "diagnostic V codes" might represent a more appropriate and correct code in the circumstance of a medically necessary screening examination found to be normal. METHODS In July 1995 the use of 11 primary diagnostic V codes and 7 secondary diagnostic V codes was discussed in our faculty meeting and a list was displayed in each examination lane. Acceptance of V codes was then tracked for an 8-month period and analyzed 1 year later to provide a set of closed accounts. RESULTS The code V71.8, or "observation for other specified, suspected condition" had a 73% acceptance rate by insurers on the basis of 207 examinations. The acceptance rate was not dependent on the use of a secondary code (76% for V71.8 alone vs 71% for secondary code used). Other V codes were infrequently used. CONCLUSIONS The code V71.8 was an accepted code by insurers in our locality for medically necessary screening examinations found to be normal. The authors feel this high acceptance rate by insurers confirms our impression that V codes are the appropriate and correct codes to use for the medically necessary screening examination found to be normal.
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Abstract
Reporters of out-of-body experiences (n = 21) and nonreporters (n = 159) showed no significant differences on the Spheres of Control Scale, Self-efficacy Scale, and Purpose in Life Scale. However, reporters of out-of-body experiences showed significantly greater belief in Psi, Spiritualism, and Extraordinary Life Forms than nonreporters.
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