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Particulate matter (PM) air pollution may increase symptom severity in allergic asthmatics. To examine possible interaction, or greater than additive responses, between PM effects and allergic responses, an ovalbumin-sensitized and challenged (OVA) mouse model of allergic airways disease was utilized. After challenge, mice were intratracheally instilled with saline vehicle or 3 mg/kg (approximately 60 microg) residual oil fly ash (ROFA), a transition metal-rich emission source PM sample. Physiological and inflammatory responses were examined 1, 3, 8, and 15 d later. In response to intravenously administered methacholine, ROFA increased total respiratory system resistance and decreased compliance 1 d after exposure, whereas effects of OVA lasted at least 15 d after exposure. Significant interactions between OVA and ROFA were mainly observed 8 d after challenge and exposure, especially with respect to compliance. A strong interaction (p < 0.01) between OVA and ROFA exposure resulted in 8-fold (1 d) and 3-fold (3 d) increases in bronchoalveolar lavage (BAL) fluid eosinophil numbers. A similarly strong interaction (8-fold) was observed in BAL fluid interleukin-4 (IL-4) 1 d after challenge and exposure. Significant though less strong interactions were also found with respect to IL-4 and IL-5 by 3 d postchallenge/exposure. This study shows that allergen challenge and exposure to emission source particulate matter containing relatively high levels of transitions metals can interact to increase Th2 cytokine production, eosinophil recruitment, and airway hyperresponsiveness in previously sensitized mice.

These results may explain the effectiveness of TNF-alpha blockade in the equilibrium condition RA and the ineffectiveness in the non-equilibrium condition SIRS.

Relationships among pH, titratable acidity (TA) and buffer composition of tomato fruits were studied using analytical data, from 25 divergent accessions, and from previous work. Citric and malic acids, and phosphate account for about 93% of the TA of tomatoes. An increase in phosphate concentration results in a decrease in [H+], whereas an increase in citric and malic acids increases [H+] These relationships probably exist because of differences in the origins of phosphate and the two acids. Variation in phosphate concentration can be of practical value in efforts to maintain a safe processing pH in low sugar, low acid varieties because phosphate has a relatively large effect on [H+] with a minimal effect on TA.

We have synthesized diploid hybrids between Lycopersicon escukntum and Solanum lycopersicoides and have converted them to allotetraploids. Two sesquidiploids, having two complements of the former parent and one of the latter, have been obtained by backcrossing the former parent with the alloploid. In meiosis of the sesquidiploid the L. esculentum chromosomes exhibit strong preferential pairing, consistently forming 12 bivalents, whereas the S. lycopersicoides chromosomes remain unpaired. This chromosomal comportment conforms with expectations based on meiosis of the 2x and 4x hybrids. Condensation of the S. lycopersicoides univalents is retarded in early diakinesis but their development appears normal at later stages. Presumably as a consequence of the orderly behavior of the L. esculentum bivalents and consequent contribution to each gamete, fertility of the sesquidiploids is higher than in L. esculentum autotriploids. The normally strict self-incompatibility is somewhat relaxed in the sesquidiploids. Extra S. lycopersicoides chromosomes can be transmitted from the sesquidiploid as pistillate parent, and the aneuploid progeny are viable. Establishment of alien addition races and their utilization to transmit desired genes from S. lycopersicoides to L. esculentum are anticipated.Thirty-five years have elapsed since the first report of successful hybridization between Lycopersicon esculentum (cultivated tomato) and Solanum lycopersicoides (wild nightshade endemic to southern Peru and northern Chile) (1). In the meanwhile intensive efforts in our laboratory and others have failed to yield progeny from selfing or sib-mating the highly sterile diploid hybrids thus generated or from backcrosses between them and L. esculentum. The parental species as well as the F1 hybrids have the same chromosome number (2n = 24). As indicated in the original report, doubling the chromosome number of the diploid hybrid results in a tetraploid with consistent bivalent chromosome pairing in meiosis and greatly improved fertility, hence a valid alloploid. Although breeding within such alloploids generates uniformly alloploid progeny, it has heretofore been impossible to backcross to diploid L. esculentum. It is the purpose of this article to report a breakthrough in this effort, yielding the expected sesquidiploid (allotriploid) hybrids by means of which transfer of desired genes from the wild parent to cultivated tomatoes may be possible.Research on chromosome pairing behavior in hybrids between these species has revealed much concerning the phylogenetic relationships of the parents. Thus, despite its extremely high sterility, the 2x F1 exhibits nearly complete pairing at meiotic pachytene (2, 3) and from a mean of 14.8 (1) to 20.2 (2) paired chromosomes at metaphase. Studies on the alloploid, on the other hand, reveal considerable differentiation between the two genomes, nearly all pairing taking place between parental homologues (4). The chromosomal pairing relations in the sesquidiploids having two sets of L. esculentum chro...

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Composition and sensory characteristics were investigated to determine the effect of ripeness at picking on fresh market flavor of ‘Cal Ace’ (1974, 1975, 1976) and ‘Cherry’, ‘Calmart’, and ‘Early Pak 7’ (1976) tomato (Lycopersicon esculentum Mill.). Tomatoes picked at earlier stages of ripeness and ripened at 20°C were evaluated by panelists as being less sweet, more sour, less “tomato-like” and having more “off-flavor” than those picked at the table-ripe stage. Objective tests showed these fruits had less sugars and reduced ascorbic acid, and varied significantly in volatile composition. The magnitude of these differences varied greatly among the cultivars. In ‘Cal Ace’ the “off-flavor” characteristic was largely correlated with a volatile compound (peak 43) but in other cultivars seven other volatile compounds also appeared to play a role.

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