A Novel Method for Quantifying the Inhaled Dose of Air Pollutants Based on Heart Rate,Breathing Rate and Forced Vital Capacity

To better understand the interaction of physical activity and air pollution exposure, it is important to quantify the change in ventilation rate incurred by activity. In this paper, we describe a method for estimating ventilation using easily-measured variables such as heart rate (HR), breathing rate (f_B), and forced vital capacity (FVC). We recruited healthy adolescents to use a treadmill while we continuously measured HR, f_B, and the tidal volume (V_T) of each breath. Participants began at rest then walked and ran at increasing speed until HR was 160–180 beats per minute followed by a cool down period. The novel feature of this method is that minute ventilation (V˙E) was normalized by FVC. We used general linear mixed models with a random effect for subject and identified nine potential predictor variables that influence either V˙E or FVC. We assessed predictive performance with a five-fold cross-validation procedure. We used a brute force selection process to identify the best performing models based on cross-validation percent error, the Akaike Information Criterion and the p-value of parameter estimates. We found a two-predictor model including HR and f_B to have the best predictive performance (V˙E/FVC = -4.247+0.0595HR+0.226f_B, mean percent error = 8.1±29%); however, given the ubiquity of HR measurements, a one-predictor model including HR may also be useful (V˙E/FVC = -3.859+0.101HR, mean percent error = 11.3±36%).     

SOME ASPECTS OF VASCULAR DIFFERENTIATION IN ROOTS OF CASSIA

Hayat, Mohammed Arif (North Dakota State U., Fargo), and Charles Heimsch. Some aspects of vascular differentiation in roots of Cassia. Amer. Jour. Bot. 50(10): 965–971. Illus. 1963.—Vascular development, with emphasis on the differentiation of the protophloem, was studied in tips of primary roots of 18 species of Cassia. Variations in levels of protophloem sieve tube maturation were observed among roots of different species as well as among those of different length in the same species. In general, protophloem matured at greater distances from the apex in roots with the larger diameters. Compared with woody species, herbaceous species exhibited greater uniformity in levels of protophloem maturation, and this was correlated with greater uniformity in root diameter. Roots were either triarch or tetrarch. In some species with tetrarch roots, a change to a triarch pattern occurred during early growth. Structural changes in the differentiating root tip which involve the loss of a xylem arm and subsequent fusion of phloem strands are described.     

THE DEVELOPMENTAL ANATOMY OF THE ANNONACEAE. I. EMBRYO AND EARLY SEEDLING STRUCTURE

Development of the epicotylary meristem is delayed; thus, it apparently has no immediate controlling influence on the procambium initiation either in the hypocotyl-root axis or in the cotyledons. Contrary to the situation found in most herbaceous dicotyledons, the procambium forms a hollow cylinder in the axis of the mature embryo. The first protophloem differentiates simultaneously in the upper part of the hypocotyl-root axis, at the base of the cotyledons, and in the cotyledons; protoxylem differentiation follows the same pattern as that of the protophloem. The direct vascular connection between the hypocotyl-root axis and cotyledons is established early in the mature embryo, and the fundamental aspects of transition phenomena are exhibited by the procambium before mature vascular elements differentiate. In the mature embryos, the pattern of lateral differentiation is irregular in that the number of protoxylem elements present at different levels is quite variable.     

Pattern of sex steroids secretion and their relationship with embryo yield in Jersey cows superovulated with PMSG

The levels of progesterone and estrogen secretion were studied in relationship to the superovulatory response in Jersey cows. Progesterone and estrogen concentrations were measured in superovulated Jersey cows with the objective of correlating the patterns of steroid secretion with embryo yield and quality. Pregnant mare serum gonadotropin (PMSG) was used in combination with prostaglandin F(2) alpha analogue to induce superovulation in 18 multiparous, cyclic cows. Serum progesterone and estradiol levels from cows which exhibited estrus within 24 to 48 h after prostaglandin administration (n=13) were used to estimate the superovulatory response. Sex steroid concentrations at the day of estrus (Day 0) was a strong indicator of embryo yield. Progesterone was negatively (r=-0.56) and estrogen positively (r=0.80) correlated to the number of embryos collected. Dramatic increase in progesterone from Day 0 to Day 7 was a significant indicator of embryo yield. A higher rise of estrogen in the follicular phase was an indicator of a larger number of growing follicles and, consequently, better superovulatory response. Nonresponding animals did not show any significant change in the hormonal profile from the day of PMSG treatment to the day of embryo collection. The estimation of progesterone and estradiol concentrations, simultaneously, gave a more objective prediction of embryo yield.     

The effects of Mg2+ and adenine nucleotides on the sensitivity of the heart mitochondrial Na+-Ca2+ carrier to extramitochondrial Ca2+. A study using arsenazo III-loaded mitochondria.

The technique of reversible Ca2+-induced permeabilization [Al Nasser & Crompton (1986) Biochem. J. 239, 19-29, 31-40] has been applied to the preparation of heart mitochondria loaded with the Ca2+ indicator arsenazo III (2 nmol of arsenazo III/mg of mitochondrial protein). The loaded mitochondria ('mitosomes') were used to study the control of the Na+-Ca2+ carrier by extramitochondrial Ca2+ mediated by putative regulatory sites. The Vmax. of the Na+-Ca2+ carrier and the degree of regulatory-site-mediated inhibition were similar to normal heart mitochondria. Ca2+ occupation of the sites in mitosomes yields partial inhibition, which is half-maximal with 0.8 microM external free Ca2+. The inhibition consists of a small decrease in Vmax. and a relatively large increase in apparent Km for internal Ca2+. Mg2+ also appears to interact with the sites, but this is largely abolished by ATP and ADP (but not AMP) under conditions in which the free [Mg2+] is maintained constant. The results indicate that the regulatory sites are effective in controlling the Na+-Ca2+ carrier at physiological concentrations of adenine nucleotides, Mg2+, intra- and extra-mitochondrial free Ca2+.     

Production, rapid purification and catalytic characterization of extracellular phytase from Aspergillus ficuum

A rapid purification scheme utilizing three chromatographic steps resulted in 6 fold purification of Aspergillus ficuum phytase (myo-inositol-hexakisphosphate 3-phosphohydrolase, EC 3.1.3.8). At pH 5.0 and 60 degrees C the enzyme performed acceptably for 2.0 hr with only 30% diminished catalytic rate at the end. Substrate concentration exceeding 2mM was inhibitory. The inorganic orthophosphate, the product and a weak inhibitor, exhibited a Ki of 1.9 x 10(-3)M. The extracellular phytase has the potential for industrial use since it can be over produced, easily purified, remain catalytically active for a longer period and is not subjected to severe product inhibition.     

Role of Burkholderia cepacia CS8 in Cd-stress alleviation and phytoremediation by Catharanthus roseus

The current study was performed to assess the effect of Burkholderia cepacia CS8 on the phytoremediation of cadmium (Cd) by Catharanthus roseus grown in Cd-contaminated soil. The plants cultivated in Cd amended soil showed reduced growth, dry mass, gas-exchange capacity, and chlorophyll contents. Furthermore, the plants exhibited elevated levels of malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) under Cd stress. The bacterized plants showed higher shoot length, root length; fresh and dry weight. The improved stress tolerance in inoculated plants was attributed to the reduced quantity of MDA and H₂O₂, enhanced synthesis of protein, proline, phenols, flavonoids, and improved activity of antioxidant enzymes including peroxidase, superoxide dismutase, ascorbate peroxidase, and catalase. Similarly, the 1-aminocyclopropane-1-carboxylate deaminase activity, phosphate solubilization, auxin, and siderophore production capability of B. cepacia CS8 improved growth and stress alleviation in treated plants. The bacterial inoculation enhanced the amount of water extractable Cd from soil. Furthermore, the inoculated plants showed higher bioconcentration factor and translocation factor. The current study exhibits that B. cepacia CS8 improves stress alleviation and phytoextraction potential of C. roseus plants growing under Cd stress.     

Gene transfer, expression and inheritance of pRSV-rainbow trout-GH cDNA in the common carp, Cyprinus carpio (Linnaeus)

A recombinant plasmid containing the Rous sarcoma virus-long terminal repeat (RSV-LTR) promoter linked to rainbow trout (Salmo gairdneri) growth hormone (GH) cDNA was microinjected into fertilized carp eggs. Genomic DNA extracted from pectoral fin of individual presumptive transgenic fish was analyzed by dot blot and Southern blot hybridization, using the RSV-LTR and/or the GH cDNA sequences as probes. Out of 365 presumptive transgenic fish analyzed, 20 individuals were found to contain pRSV-rtGH-cDNA sequence in the genomic DNA. Expression of the trout GH polypeptide was detected by immunobinding assay in the red blood cells of nine transgenic fish tested. The level of expression, however, varied among the transgenics and could not be correlated with exogenous DNA copy number. Although there was considerable variation in the sizes of the transgenic fish, those microinjected during the one-cell stage were (P less than 0.05) 22% larger, on the average, than their sibling controls. A randomly selected fraction of the progeny derived from crosses between transgenic males and non-transgenic females inherited the foreign DNA. These transgenic progeny grew faster (P less than 0.05) than their non-transgenic siblings.