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B Brimhall

Publications and source records attributed to B Brimhall.

At least 19 recordsLinked to original sources
PubMed2001

The relationship between the clinical features of pharyngitis and the sensitivity of a rapid antigen test: evidence of spectrum bias.

STUDY OBJECTIVE: We evaluate the test characteristics and test for spectrum bias of a rapid antigen test for group A beta-hemolytic streptococcal (GABHS) pharyngitis among adults. METHODS: Medical record and laboratory results of consecutive adult patients receiving a rapid antigen test for GABHS in the emergency department or urgent care clinic of an urban teaching hospital between August 1999 and December 1999 were analyzed. Patients were stratified according to the number of clinical features present using the following modified Centor criteria: history of fever, absence of cough, presence of pharyngeal exudate, and cervical lymphadenopathy. The sensitivity of the rapid antigen test was defined as the number of patients with positive rapid antigen test results divided by the number of patients with either positive rapid antigen test results or negative rapid antigen test results and positive throat culture results. RESULTS: In the study sample of 498 patient visits, the prevalence of GABHS pharyngitis was 28% (95% confidence interval [CI] 24% to 32%). The prevalence of GABHS pharyngitis increased as modified Centor scores increased: 0 or 1=14%, 2=20%, 3=43%, and 4=52%. An increased number of modified Centor criteria (0 or 1, 2, 3, 4) was associated with increased rapid antigen test sensitivity (61%, 76%, 90%, and 97%, respectively) (Mantel-Haenszel trend test; P =.001). CONCLUSION: The sensitivity of the rapid antigen test for GABHS is not a fixed value but varies with the spectrum of disease. Among adults with 3 or 4 clinical criteria for GABHS pharyngitis, further study may reveal that culture confirmation of negative rapid antigen test results are not necessary.

Adolescent↗
PubMed1990

Two families with hemoglobin Sogn, beta(A11)14 Leu----Arg, in Minnesota and Indiana: hematologic, functional, and biosynthetic features.

Sogn hemoglobinopathy was identified in a young American woman and in a young American man of apparently unrelated families of Norwegian ancestry. Both persons were asymptomatic and without clinical or hematologic manifestations. Hemoglobin Sogn, beta(A11)14 Leu----Arg, is an unstable hemoglobin that may easily be mistaken for hemoglobin S, G, or D by alkaline hemoglobin electrophoresis. These are the first known instances of hemoglobin Sogn outside of Norway. Oxygen affinity is normal. Sogn hemoglobinopathy is an incidental finding that has no adverse implication for the health of heterozygotes.

Adult↗
PubMed1983

Hb S Mobile: a new genetic combination.

The genetic combination of Hb Mobile (beta 73 Asp replaced by Val) and Hb S (beta 6 Glu replaced by Val) was found in a healthy black man whose hemolysate resembles that of Hb S electrophoretically. His mother and sister have Hb AS; the father and brother have Hb A Mobile. No clinical nor hematologic abnormalities were detected in any member of the family. A slightly decreased oxygen affinity associated with Hb Mobile appears to have no clinical significance. Simple methods of differentiating Hb Mobile S from the electrophoretically similar but clinically severe Hb SD Los Angeles are described.

Adolescent↗
PubMed1980

Oxygen affinity and stability of hemoglobin Dunn alpha 6(A4)Asp replaced by Asn): use of isoelectric focusing in recognition of a new abnormal hemoglobin.

A new slow-moving hemoglobin was found in low proportion in an asymptomatic black woman. Isoelectric focusing helped to distinguish it from other hemoglobins with similar electrophoretic mobility, and amino acid analysis showed that aspartic acid alpha 6 (A4) had been replaced by asparagine. Oxygen affinity was increased, but the Bohr and DPG effects were normal. Stability of the purified hemoglobin was decreased, but that of hemolysates was normal. Abnormal oxygen affinity of this variant, and that of hemoglobin Sawara (alpha 6(A4)Asp replaced by Ala), may reflect loss of a salt bridge between Asp alpha 6 and Lys-alpha 127(H10) which would tend to favor the high-affinity R conformation of the molecule.

Adult↗
PubMed1979

Tryptic peptide analysis and NH2-terminal amino acid sequences of polyhedrins of two baculoviruses from Orgyia pseudotsugata.

Comparative analysis of the tryptic peptides and terminal amino acid sequence was made on polyhedrins from two genetically different baculoviruses that are naturally pathogenic for the same insect host. Comparison of the tryptic peptides of the nucleopolyhedrosis bundle virus and nucleopolyhedrosis single-rod virus of Orgyia pseudotsugata by means of cation-exchange resins indicated that the proteins have a closely related amino acid sequence. The NH(2)-terminal amino acid sequence of polyhedrins from the two viruses differed in only 4 out of 34 amino acids. The nucleopolyhedrosis bundle virus and the nucleopolyhedrosis single-rod virus also differed in 4 and 5 out of 34 terminal amino acids, respectively, from the sequence reported for polyhedrin of a baculovirus of Bombyx mori [Serebryani, S. B., Levitina, T. L., Kautsman, M. L., Radavski, Y. L., Gusak, N. M., Ovander, M. N., Sucharenko, N. V. & Kozlov, E. A. (1977) J. Invertebr. Pathol. 30, 442-443]. In addition, the nucleopolyhedrosis single-rod virus had two amino acids (Met-Tyr) on the NH(2) terminus that were not present on the terminus of nucleopolyhedrosis bundle virus or B. mori baculovirus polyhedrin. Approximately half (six) of the total tyrosine residues are clustered in the terminal 20 amino acids of the polyhedrins. Secondary structures predicted from the primary sequence suggest that the tyrosines are clustered in two areas. This nonrandom distribution and the pK(a) of about 10 for tyrosine may be related to the alkali solubility of the polyhedrin.

Amino Acid Sequence↗
PubMed1979

Comparison of hemoglobins Wood (alpha 2 beta 2 97 leu) and Malmö (alpha 2 beta 2 97 gln). Diagnostic value of citrate agar electrophoresis.

Diagnostic value of citrate agar electrophoresis. Am J Clin Pathol 71:668-671, 1979. Of approximately three dozen hemoglobin variants that have greater than usual oxygen affinity, nearly half are inseparable from hemoglobin A by electrophoresis at pH 8.6. A comparison of hemoglobins Wood (alpha2beta297leu) and Malmö (alpha2beta297gln) is of interest from several standpoints. They represent similar substitutions at the identical locus in the beta chain. They result in identical clinical and hematologic manifestations. Oxygen affinities of these variants are identical. Both are poorly resolved from hemoglobin A by electrophoresis at pH 8.6. The position of each is identical when studied by isoelectric focusing in polyacrylamide gel. Finally, they are easily distinguished by citrate agar electrophoresis at pH 6.2. The excellent resolution of hemoglobins Malmö and Wood from each other results neither from difference in charge, nor size, nor in quaternary structure. This technic provides a simple but effective means for identifying and differentiating these hemoglobin variants. Comparison with the results of citrate agar electrophoresis of other high oxygen-affinity hemoglobins indicates that the findings for hemoglobins Malmö and Wood are unique and unambiguous.

Adolescent↗
PubMed1979

Hemoglobin Cowtown (beta 146 HC3 His-Leu): a mutant with high oxygen affinity and erythrocytosis.

A new mutant, hemoglobin Cowtown, has been found in a white man and his father, both of whom have erythrocytosis. The father had previously been treated with 32P for polycythemia vera. The abnormal hemoglobin is not detectable on electrophoresis in alkaline buffers, but it resolves distinctively on electrophoresis in citrate agar, pH 6.0; similarly, the abnormal beta-globin chain does not separate from beta-A in urea 2-mercaptoethanol buffers of pH 8.9, but it moves anodically to beta-A at pH 6.0. Peptide chromatography and amino acid analysis of the beta chain reveal that the C-terminal histidine residue (beta 146) has been replaced by leucine. Like several other hemoglobins substituted at this residue, Hb Cowtown has a high oxygen affinity and a diminished Bohr effect.

Adult↗
PubMed1979

Tyrptic peptide compositions of hemoglobins from mink (Mustela vison) and hyena (Hyaenae hyaenae) and the alpha-chain of coatimundi (Nasua nasua).

The amino acid composition of the tryptic peptides from hyena hemoglobin, two hemoglobins of the mink and the alpha-chain of coatimundi have been determined, allowing comparison with data previously obtained from other carnivores. The two hemoglobins of mink differ at only one amino acid residue, alpha 15, which is glycyl in one hemoblobin and aspartyl in the other.

Amino Acids↗
PubMed1979

Hemoglobin E trait reexamined: a cause of microcytosis and erythrocytosis.

The current Indochinese resettlement program in the United States has resulted in an increase in the number of persons with hemoglobin E trait. American physicians should be aware of the hematologic expressions of this innocuous condition. The hematologic manifestations of 21 persons with hemoglobin E trait were evaluated. The subjects were of Tai-dam, Vietnamese, Chinese, Laotian, and European origin. These studies showed uniform hematologic manifestations in hemoglobin E trait, characterized by slight microcytosis, by morphologic features resembling those of thalassemia minor, and often by increased erythrocyte count. Hemoglobin instability also was confirmed.

Adolescent↗
PubMed1978

Amino acid sequence of hemerythrin from Themiste dyscritum.

The amino acid sequence of hemerythrin from the sipunculid worm, Themiste dyscritum, was determined by sequenator analyses of the S-pyridylethylated protein and fragments derived by further chemical and enzymatic cleavages. The fragments were obtained by cleavage of the intact protein with hydroxylamine, trypsin digestion of citraconylated intact protein, and subdigestion with Staphylococcal protease V8. The COOH-terminal sequence was determined using carboxypeptidases A and B and amino acid analyses. The polypeptide chain was found to contain 113 amino acids. Since heterogeneity was observed at no more than two positions in the amino acid sequence, the native octameric protein appears to be composed of identical subunits. By combining information derived from sequence analyses and x-ray crystallographic studies, it has been possible to identify amino acids responsible for the tertiary and quaternary structure of the protein as well as amino acids serving as iron ligands at the oxygen-binding site.

Amino Acid Sequence↗
PubMed1978

Amino acid sequence of the hemoglobin of raccoon (Procyon lotor).

The amino acid sequences of the hemoglobin alpha- and beta-chains of raccoon have been determined by a combination of manual and automatic sequencing procedures. The raccoon beta-chain shows 16 amino acid differences from that of dog. The alpha chain shows 10 differences. These values are identical with those predicted by analogy from their tryptic peptide compositions.

Amino Acid Sequence↗
PubMed1978

Hb Potomac (101 Glu replaced by Asp): speculations on placental oxygen transport in carriers of high-affinity hemoglobins.

Blood from a woman with unexplained erythrocytosis had increased oxygen affinity, but no abnormality could be detected by electrophoresis or chromatography of her hemolysate. Separation of the tryptic peptides of her beta chains disclosed two half-sized peaks in the regions of beta T-11. The faster of these was abnormal, with the structure beta 101 Glu replaced by Asp. The new hemoglobin was called "Potomac." Three of the proband's four surviving siblings and both of her children were carriers. Differences in the ratio of carrier: normal children born to male of female carriers of 23 other high-affinity hemoglobins were not significant. The high proportion of carriers in this kindred was probably due to chance alone, and not because high maternal oxygen affinity interfered with oxygen transport to fetuses with normal hemoglobin.

Adult↗
PubMed1977

The amino acid sequence of dog (Canis familiaris) hemoglobin.

The manual sequencing of the tryptic peptic from the alpha and beta chains of dog hemoglobin is described, including evidence for the existence of two alphaT-13 peptides and thus 2 alpha chains, one with threonine and one with alanine at position 130. Although the actual sequence was published in 1970, the evidence on which it was based has not previously appeared.

Amino Acid Sequence↗
PubMed1977

On the tryptic peptides from hemoglobin chains of six carnivores.

The amino acid compositions of the tryptic peptides of the following carnivore hemoglobin chains have been determined: gray fox (Urocyon cineroargenteus); raccoon (Procyon lotor); polar bear (Thalarctos maritimus); coati mundi (Nasua nasua) beta chain; coati mundi (Nasua narica) two beta chains; cat (Felis catus) alpha chain; and lion (Pantbera leo) beta chain. These provide a basis for future sequencing of these hemoglobins and construction of an evolutionary tree. The specific results are summarized in the following article (Stenzel and Brimhall, 1977).

Amino Acid Sequence↗
PubMed1977

The tryptic peptide composition of the beta chains of hemoglobins A and B of the Domestic cat (Felis catus)

The tryptic peptides from the betaA and betaB chains of cat hemoglobins A and B have isolated and the amino acid compositions determined. Differences between the two chains were found in two peptides, betaT-1 (Glylead toSer) and betaT-14 (Asnlead toSer and Lyslead toArg). The Glylead toSer and Lysleand toArg substitutions areplaced at beta-1 and beta-144 respectively from earlier work, and the third substitution, AsnleadSer at beta-139 is suggested from this work. in addition, the presence of a blocked amino terminus in betaB has been confirmed. Tentative sequences constructed by homology with known beta-chain structures suggest the occurrence of substitutions at alpha1beta1 contacts in betaA and betaB that may be functionally significant. There are at least 18 differences in amino acid composition between cat betaA and dog beta-chains and 22 differences between cat betaA and normal adult human beta-chains.

Amino Acid Sequence↗