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Biomedical subjects

B L Rogers

Publications and source records attributed to B L Rogers.

17 recordsLinked to original sources

Expression and genomic structure of the genes encoding FdI, the major allergen from the domestic cat.

The genes encoding chain 1 (Ch1) and chain 2 (Ch2) of the major allergen of the domestic cat, Felis domesticus I, have been analyzed by genomic cloning and by polymerase chain reaction (PCR). Ch1 has two potential leader sequences, designated A and B. Analysis of a genomic clone encoding Ch1 demonstrated that one structural gene contains sequences corresponding to both leaders, which utilize different Met start codons. PCR analysis showed that genes encoding Ch1 and Ch2 are co-expressed in both the salivary glands and the skin, and that leader sequence A of Ch1 is utilized preferentially in both tissues. Ch2 was shown to have two dominant forms that are differentially expressed in the aforementioned tissues. The long form (Ch2L), composed of 92 amino acids (aa), is preferentially expressed in the salivary glands, while the short form (Ch2S), composed of 90 aa, is preferentially expressed in the skin. There is minor sequence polymorphism in both forms of Ch2. A genomic clone for Ch2 only contained sequences for Ch2S, suggesting that Ch2L is encoded by an exon not contained within this genomic clone.

Allergens

Evaluation of the impact of weaning food messages on infant feeding practices and child growth in rural Bangladesh.

In rural Bangladesh, a community-based weaning intervention used volunteers to teach complementary feeding to families of 62 breast-fed infants aged 6-12 mo. Over 5 mo, treatment children gained on average 0.46 SD (approximately 460 g) more in weight-for-age (WAZ) than the 55 control subjects, and were approximately 0.5 kg heavier at the final measure. The differences were statistically significant (P < 0.001). The percent median weight-for-age (WAPM) of treatment children held steady at 76% of the National Center for Health Statistics' reference, whereas the WAPM of control subjects dropped from 78% to 72%. The increase in percentage points of severe malnutrition (below -3 WAZ) was only 5% in the treatment group compared with 26% in the control subjects. Treatment children consumed a significantly greater percent of their energy and protein requirements from complementary foods than did control subjects. The affordable complementary foods consisted mainly of cereal porridge with oil and brown sugar. These findings suggest that educational interventions teaching families to feed hygienic, simple, cheap, energy-enriched complementary foods to breast-fed infants after 5-6 mo can improve child growth, even under impoverished conditions.

Bangladesh

Project director characteristics in the Elderly Nutrition Program.

The federally funded Elderly Nutrition Program (ENP) began in 1972, authorized under Title 7 of the Older Americans Act. Its purpose was to serve elders, targeting those in greatest social and economic need. This article describes the characteristics of the Nutrition Project Directors in the ENP through data gathered by a questionnaire completed by a random sample of 430 directors across the nation. One important finding was that directors of programs serving large numbers of low-income or minority elders tended to have less education and commanded lower salaries than directors serving fewer poor and minority elders. In addition, while a higher proportion of these directors were minority members, numbers of nonwhite Nutrition Project Directors remains low.

Educational Status

Amino acid sequence of Fel dI, the major allergen of the domestic cat: protein sequence analysis and cDNA cloning.

The complete primary structure of Fel dI (International Union of Immunological Societies nomenclature), the major allergen produced by the domestic cat, Felis domesticus, was determined by protein sequence analysis and cDNA cloning. Protein sequencing of Fel dI from an immunoaffinity-purified extract of house dust revealed that the allergen is composed of two polypeptide chains. Degenerate oligonucleotides derived from the protein sequence were used in polymerase chain reaction amplification of cat salivary gland cDNA to demonstrate that the two chains are encoded by different genes. Chain 1 of Fel dI shares amino acid homology with rabbit uteroglobin, while chain 2 is a glycoprotein with N-linked oligosaccharides.

Allergens

Complete sequence of the allergen Amb alpha II. Recombinant expression and reactivity with T cells from ragweed allergic patients.

This study defines the complete primary structure of Amb alpha II, an important allergen produced by short ragweed (Ambrosia artemisiifolia). The deduced amino acid sequence derived from the cDNA indicates that Amb alpha II shares approximately 65% sequence identity with the Amb alpha I multigene family of allergens. Full-length cDNA encoding Amb alpha I.1 and Amb alpha II have been expressed in E. coli and purified. An in-frame linker encoding polyhistidine has been added to the 5' end of the cDNA to facilitate purification using Ni2+ ion affinity chromatography, yielding greater than 90% pure recombinant protein in a single step. T cells from patients allergic to ragweed proliferate in response to pollen extract as well as purified recombinant Amb alpha I.1 and Amb alpha II. T cell lines established using either Amb alpha I.1 or II as the stimulating Ag exhibit a high level of cross-reactivity to both proteins. This result is entirely consistent with the extensive primary sequence identity shared by these two proteins. These data suggest that allergic humans recognize shared T cell epitopes on these two related molecules.

Allergens

Multiple Amb a I allergens demonstrate specific reactivity with IgE and T cells from ragweed-allergic patients.

The relationship between the structure and abundance of an inhaled protein and its potential for causing an allergic response is unknown. This study analyzes Amb a I, a family of related proteins formerly known as Ag E, that comprise the major allergens of short ragweed (Ambrosia artemisiifolia). T cells isolated from ragweed allergic patients were shown to proliferate in response to purified Amb a I.1 protein from pollen in in vitro secondary cultures, demonstrating the presence of T cell stimulatory epitopes in Amb a I.1. Three recombinant forms of Amb a I (Amb a I.1, Amb a I.2, and Amb a I.3) obtained as cDNA derived from pollen mRNA were expressed in bacteria. All three recombinant forms were shown to be specifically recognized by pooled ragweed-allergic human IgE on immunoblots, confirming these gene products are important allergens. An examination of immunoblots probed with sera derived from allergic patients revealed a variation in IgE binding specificity. A minority of patients' IgE exclusively reacted with recombinant Amb a I.1, whereas most patients' IgE reacted with Amb a I.1 as well as Amb a I.2 and Amb a I.3 proteins. A detailed examination of the reactivity of T cells derived from 12 allergic patients to these recombinant Amb a I forms revealed that these allergens are all capable of stimulating T cell proliferation in in vitro assays. It is concluded that the allergic response to ragweed pollen in most allergic patients is composed of a reaction to multiple related Amb a I proteins at both the B and T cell levels.

Allergens

Cloning of Amb a I (antigen E), the major allergen family of short ragweed pollen.

To determine the structure of Amb a I (previously called antigen E), the major allergen from short ragweed, cDNA from pollen was cloned into lambda gt11 and lambda gt10. One of the three distinct clones isolated from the lambda gt11 library by screening with anti-denatured Amb a I antibodies was used to screen both libraries for other Amb a I sequences. Multiple clones were isolated and sequenced and proved to be highly homologous but nonidentical. The clones could be divided into three groups based on sequence similarity, and in accordance with the International Union of Immunological Societies-approved nomenclature (Marsh, D. G., Goodfriend, L., King, T. P., Lowenstein, H., and Platts-Mills, T. A. E. (1986) Bull. WHO 64, 767-770) they have been designated Amb a I.1, Amb a I.2, and Amb a I.3. Clones within a group have greater than 99% identity, and similarity among groups is 85-90% at the nucleotide level. The amino acid sequence of four peptides (isolated from antigen E obtained from the Research Resources Branch of the National Institutes of Health) containing 132 amino acids was identical to one of the clones (Amb a I.1). The presence of multiple naturally occurring isoelectric forms of Amb a I was demonstrated by two-dimensional gel electrophoresis and Western blotting. Southern blot analysis demonstrates the presence of multiple Amb a I-related sequences in the ragweed genome. Amb a I is therefore not a single molecule but rather a family of closely related proteins.

Allergens

Sequence polymorphism of Amb a I and Amb a II, the major allergens in Ambrosia artemisiifolia (short ragweed).

Two of the major allergens in the pollen of short ragweed are Amb a I and Amb a II (formerly antigen E and antigen K, respectively). The genes for Amb a I and Amb a II have recently been cloned, and it was shown that Amb a I is a family of proteins with at least three distinct polymorphic family members. This study addresses the number of individual Amb a I and Amb a II family members, the polymorphism in each family member and the expression of these genes in ragweed plants from different geographical locations. This work led to the cloning and characterization of a fourth Amb a I family member, designated Amb a I.4.

Allergens

School Breakfast Program and school performance.

To test the hypothesis that participation in the School Breakfast Program by low-income children is associated with improvements in standardized achievement test scores and in rates of absence and tardiness, children in grades 3 through 6 were studied in the Lawrence, Mass, public schools, where the School Breakfast Program was begun at the start of the second semester 1986-1987 school year. The changes in scores on a standardized achievement test and in rates of absence and tardiness before and after the implementation of the School Breakfast Program for children participating in the program were compared with those of children who also qualified but did not participate. Controlling for other factors, participation in the School Breakfast Program contributed positively to the 1987 Comprehensive Tests of Basic Skills battery total scale score and negatively to 1987 tardiness and absence rates. These findings suggest that participation in the School Breakfast Program is associated with significant improvements in academic functioning among low-income elementary school children.

Absenteeism

Foodservice trends in the elderly nutrition program.

The foodservice delivery aspects of the federally-funded Elderly Nutrition Program (ENP) were examined via an original survey instrument sent to a random sample of nutrition projects nationally. In comparison to a similar survey conducted a decade ago, projects were more apt to rely on a combination of foodservice mechanisms including caterer contracts, on-site preparation, and use of central kitchens.

Aged

Expression of the T-cell receptor gamma-chain gene products on the surface of peripheral T cells and T-cell blasts generated by allogeneic mixed lymphocyte reaction.

The gamma-chain genes of the T-cell receptors form a family of related genes that are specifically expressed and somatically rearranged in T cells. Using poly- and monoclonal anti-gamma antibodies, we studied the cell-surface expression of the gamma-chain gene products in mouse peripheral T cells as well as in the T-cell blasts generated by allogeneic mixed lymphocyte reactions. The gamma chains are expressed in the Lyt2-,L3T4- subsets of these T-cell populations as disulfide-linked heterodimers. Whereas the electrophoretic mobility and the N-glycosylation of the spleen and lymph-node gamma chains are indistinguishable from those of the reported thymocyte gamma chain, a minor fraction of the T blasts generated by allogeneic stimulation of B10 lymph-node T cells with B10.BR spleen cells seems to express gamma chains with distinct properties. This suggests that the mixed lymphocyte culture conditions exert a selective effect on the expression of gamma chains among peripheral T-cell populations.

Animals

Transcriptional enhancer within the human placental lactogen and growth hormone multigene cluster.

Human placental lactogen (hPL) and human growth hormone (hGH) are members of a multigene family that share amino acid sequence homology and similarity in gene structure and nucleotide sequence, but differ in both function and expression. To determine the sequence requirements for tissue specific expression recombinant plasmids containing the members of the hPL-hGH multigene family and flanking regions were analyzed by both transient and stable transfection assays. We have identified a transcriptional enhancer in a 1.0 kb region located 2.0 kb downstream of the hPL3 structural gene. This enhancer sequence is not strictly cell-type specific since it functions in cell lines of both placental (JEG-3) and pituitary (18-54,SF) origin. However, its efficiency is several fold higher in placental cells than in pituitary cells.

Base Sequence

Synthesis and biological activity of derivatives of ubiquinone: photoaffinity analogues containing the 4-azido-2-nitroanilino group.

The photoaffinity analogues of ubiquinone 2,3-dimethoxy-5-methyl-6-[2-[1-oxo-3-(4-azido-2-nitroanilino) propoxy]-3-methylbutyl]-1,4-benzoquinone (2'-ANAP-Q-1) and 2,3-dimethoxy-5-methyl-6-[3-[1-oxo-3-(4-azido-2-nitroanilino) propoxy]-3-methylbutyl]-1,4-benzoquinone (3'-ANAP-Q-1) have been synthesized. The required intermediate alcohols 2,3-dimethoxy-5-methyl-6-(2-hydroxy-3-methylbutyl)-1,4-benzoquinone and 2,3-dimethoxy-5-methyl-6-(3-hydroxy-3-methylbutyl)-1,4-benzoquinone were prepared in good yield from ubiquinone 1 by hydration of the side-chain double bond via hydroboration or acid catalysis, respectively. These alcohols were then coupled with 3-(4-azido-2-nitroanilino)propanoic acid, with p-toluenesulfonyl chloride in dry pyridine, to give 2'- and 3'-ANAP-Q-1. The synthetic methods presented should be of general utility in the preparation of derivatives of ubiquinone in which a reactive or reporter group is relatively close to the ubiquinone ring. By use of membrane vesicles prepared from a ubi-men-strain of Escherichia coli described previously [Wallace, B., & Young, I. G. (1977) Biochim. Biophys. Acta 461, 84-100], it has been shown that 2'- and 3'-ANAP-Q-1 substitute for ubiquinone 8 in the NADH, succinate, and D-lactate oxidase systems. Thus, these compounds may be of value in labeling respiratory chain proteins that interact with ubiquinone.

Affinity Labels