Exhaled and nasal NO (ENO, NNO) have been suggested as markers for inflammation in lower and upper respiratory tract respectively. It is still unknown how a number of factors, apart from airway inflammation, can influence NO levels. The aim of this study was to determine the effect of a nitrate-rich meal on ENO and NNO. Sixteen healthy subjects were observed during 1 week on normal diet before a nitrate-restricted diet was introduced in the next. On day 3 of the second week they were made to ingest a nitrate rich meal. ENO, NNO, plasma nitrate and plasma L-arginine were followed before the meal and afterwards for 3 h. ENO and NNO as well as plasma nitrate and plasma L-arginine were significantly elevated after the nitrate-rich meal. The median maximal increase of ENO and NNO was 47% and 13% respectively. We found a moderate but significant correlation between the rise in plasma nitrate and ENO (r(s)=0.57, P=0.027) but none between plasma nitrate and NNO (r(s)=-0.02, P=0.95). As nitrate in the diet seems to substantially influence the levels of ENO it is important either to restrict or register the intake of nitrate-rich food prior to measuring ENO.

Cattle have a limited range of immunoglobulin genes which are further diversified by antigen independent somatic hypermutation in fetuses. Junctional diversity generated during somatic recombination contributes to antibody diversity but its relative significance has not been comprehensively studied. We have investigated the importance of terminal deoxynucleotidyl transferase (TdT) -mediated junctional diversity to the bovine immunoglobulin repertoire. We also searched for new bovine heavy chain diversity (IGHD) genes as the information of the germline sequences is essential to define the junctional boundaries between gene segments. New heavy chain variable genes (IGHV) were explored to address the gene usage in the fetal recombinations. Our bioinformatics search revealed five new IGHD genes, which included the longest IGHD reported so far, 154 bp. By genomic sequencing we found 26 new IGHV sequences that represent potentially new IGHV genes or allelic variants. Sequence analysis of immunoglobulin heavy chain cDNA libraries of fetal bone marrow, ileum and spleen showed 0 to 36 nontemplated N-nucleotide additions between variable, diversity and joining genes. A maximum of 8 N nucleotides were also identified in the light chains. The junctional base profile was biased towards A and T nucleotide additions (64% in heavy chain VD, 52% in heavy chain DJ and 61% in light chain VJ junctions) in contrast to the high G/C content which is usually observed in mice. Sequence analysis also revealed extensive exonuclease activity, providing additional diversity. B-lymphocyte specific TdT expression was detected in bovine fetal bone marrow by reverse transcription-qPCR and immunofluorescence. These results suggest that TdT-mediated junctional diversity and exonuclease activity contribute significantly to the size of the cattle preimmune antibody repertoire already in the fetal period.

The human parvovirus B19 is now divided into three genotypes: type 1 (prototype), type 2 (A6-and LaLi-like), and type 3 (V9-like). In overall DNA sequence, the three virus types differ by ϳ10%. The most striking DNA dissimilarity, of >20%, is observed within the p6 promoter region. Because of the scarcity of data on the biological activities and pathogenetic potentials of virus types 2 and 3, we examined the functional characteristics of these virus types. We found the activities of the three p6 promoters to be of equal strength and to be most active in B19-permissive cells. Virus type 2 capsid protein VP2, alone or together with VP1, was expressed with the baculovirus system and was shown to assemble into icosahedral parvovirus-like particles, which were reactive in the hemagglutination assay. Furthermore, sera containing DNA of any of the three B19 types were shown to hemagglutinate. The infectivities of these sera were examined in two B19-permissive cell lines. Reverse transcription-PCR revealed synthesis of spliced B19 mRNAs, and immunofluorescence verified the production of NS and VP proteins in the infected cells. All three genotypes showed similar functional characteristics in all experiments performed, showing that the three virus types indeed belong to the same species, i.e., human parvovirus B19. Additionally, the antibody activity in sera from B19 type 1-or type 2-infected subjects (long-term immunity) was examined with homo-and heterologous virus-like particles. Cross-reactivity of 100% was observed, indicating that the two B19 genotypes comprise a single serotype.Human parvovirus B19, a member of the genus Erythrovirus within the subfamily Parvovirinae, has long been considered the only human pathogen of its family, in which the adeno-associated viruses of the genus Dependovirus conceivably are apathogenic. However, new parvoviruses distinct from the genus Erythrovirus were recently detected in plasma (PARV4 and PARV5) (20, 28) and in nasopharyngeal aspirates (human bocavirus) (1), the last of which is supposedly associated with severe respiratory illness in small children.Although infection with parvovirus B19 typically results in erythema infectiosum or fifth disease (4), more severe or even lethal manifestations can occur among predisposed individuals. The virus replicates in erythroid progenitor cells of bone marrow (49, 64), causing aplastic crisis in patients with hemolytic anemia of various etiologies (2, 53, 56). During pregnancy, B19 can be transmitted from the infected mother to the fetus and cause fetal hydrops and death (9). In the immunocompromised, B19 infection may remain persistently productive, leading to chronic anemia (31).The B19 virus is small and nonenveloped and encapsidates a linear single-stranded DNA genome of ϳ5.6 kb. The two genomic ends contain identical inverted terminal repeats of ϳ380 nucleotides that are imperfect palindromes and form hairpin loops (13). The genome contains only one functional promoter, p6, located in the 3Ј palindrome (15). The p6 promoter regulates...

Background: The assortment of cattle immunoglobulin and surrogate light chain genes has been extracted from the version 3.1 of Bos taurus genome sequence as a part of an international effort to sequence and annotate the bovine genome.