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The signals controlling the abundance of transcripts up-regulated (pTIP27, pTIP31, and pTIP32) or down-regulated (pTIP20 and pTIP21) after harvest in asparagus (Asparagus officinalis L.) spears were examined. pTIP27 and pTIP31 are known to encode asparagine synthetase (AS) and a beta-galactosidase (beta-gal) homolog, respectively. The nucleotide sequences of pTIP20, pTIP21, and pTIP32 were determined, and they encode histone 3, histone 2B, and an unknown product, respectively. Changes in respiration, soluble sugars, and abundance of the five mRNAs were similar in the tips stored as 30-mm lengths or as part of 180-mm spears. We previously hypothesized that sugars may regulate the level of AS transcripts in asparagus tissue. Asparagus cell cultures were used to test the role of sugar status may regulate the level of AS transcripts in asparagus tissue. Asparagus cell cultures were used to test the role of sugar status in regulating gene expression. Transcript abundance for AS, beta-gal, and pTIP32 was low in cells in sugar-containing medium but increased within 12 h after transferring cells to a sugar-free medium. Histone 3 and histone 2B transcripts were, in general, abundant in cells on sugar-containing medium but declined in abundance when transferred to sugar-free medium. When cells were returned to sugar-containing medium the abundance of transcripts for histone 3 and histone 2B increased, whereas that for AS, beta-gal, and pTIP32 decreased. Soluble sugar levels are known to decline rapidly in the tips of harvested spears. Metabolic regulation by sugar status may have a major influence on gene expression in asparagus spears and other tissue after harvest.

Ions of structure X[N(O)NO]- display broad-spectrum pharmacological activity that correlates with the rate and extent of their spontaneous, first-order decomposition to nitric oxide when dissolved. We report incorporation of this functional group into polymeric matrices that can be used for altering the time course of nitric oxide release and/or targeting it to tissues with which the polymers are in physical contact. Structural types prepared include those in which the [N(O)NO]- group is attached to heteroatoms in low molecular weight species that are noncovalently distributed throughout the polymeric matrix, in groupings pendant to the polymer backbone, and in the polymer backbone itself. They range in physical form from films that can be coated onto other surfaces to microspheres, gels, powders, and moldable resins. Chemiluminescence measurements confirm that polymers to which the [N(O)NO]- group is attached can serve as localized sources of nitric oxide, with one prototype providing sustained NO release for 5 weeks in pH 7.4 buffer at 37 degrees C. The latter composition, a cross-linked poly-(ethylenimine) that had been exposed to NO, inhibited the in vitro proliferation of rat aorta smooth muscle cells when added as a powder to the culture medium and showed potent antiplatelet activity when coated on a normally thrombogenic vascular graft situated in an arteriovenous shunt in a baboon's circulatory system. The results suggest that polymers containing the [N(O)NO]- functional group may hold considerable promise for a variety of biomedical applications in which local delivery of NO is desired.

Vertebral fracture prevalence and severity were analyzed by sex and age in an age-stratified proportionate sample of the enumerated population of women and men 50 years of age and older in Saunders County, Nebraska. The sample consisted of 899 women and 529 men. Of these, all but 10 women and 2 men had readable lateral spine radiographs. For both sexes, fracture prevalence rises with age. Women in their fifties have 10% vertebral fracture prevalence, and women in their eighties, 45% prevalence. Men in their fifties have 29% prevalence, and men in their eighties, 39% prevalence. The rise in prevalence and total spinal deformity with age is much greater for women than for men, but the prevalence of vertebral deformity in the fifties is much greater in men than in women.

Ultrasonic measures of bone have been available for clinical research purposes for nearly 10 years, yet there still seems to be a need to compare ultrasound with the accepted gold standard of densitometry. Recently there have been published reports showing that ultrasound measures are associated with both appendicular and hip fracture, in particular after adjustment for densitometry measures. We present here a comparison between speed of sound through the patella and forearm bone densitometry, using their association with prevalent vertebral fractures in a population-based study of women and men. The prospective phase of the Saunders Bone Quality Study includes 1401 women and men who had baseline spine radiographs, patellar ultrasound, and forearm densitometry measurements. Multivariate forward logistic regression was used to determine the age-adjusted odds of vertebral fracture, the number of fractures, and the severity of these fractures, when patellar ultrasound and each of four forearm densitometry measures were entered into the model. Age is the most important factor associated with vertebral fractures, their number, and severity for women, while age is not significantly related to vertebral fractures for men. Of the bone status measures, patellar ultrasound entered the logistic regression models more consistently than any other measure except ulnar bone mineral density for women. The ultrasound measure entered every model for men. We conclude that patellar ultrasound velocity is more consistently associated with the odds of vertebral fractures than radius bone mineral content.

Broccoli (Brassica oleracea L.) floral tissues rapidly differentiate and grow before harvest and then senesce rapidly after harvest. Associated with this postharvest deterioration is an increase in ethylene production by florets. Two cDNA clones having high nucleotide identity to sequences encoding 1-amino-cyclopropane-1-carboxylic acid (ACC) oxidase were isolated from senescing florets. The cDNAs, ACC Ox1 and ACC Ox2, apparently encode mRNAs from different genes. ACC Ox1 transcripts were found at low levels in whole florets at the time of harvest and increased markedly in abundance after harvest. ACC Ox1 transcript abundance also increased in sepals after harvest and in excised yellowing leaves. Transcripts corresponding to ACC Ox2 were found exclusively within the reproductive structures. These ACC Ox2 transcripts were absent at harvest but started to increase in abundance within 2 h of harvest and then accumulated to high levels. Hormone treatment did not alter the abundance of ACC Ox1 transcripts, whereas ACC Ox2 transcripts increased in abundance after treatment with abscisic acid and propylene. Wounding did not affect the levels of ACC Ox1 or Ox2 transcripts after harvest. At harvest, individual broccoli florets were closed and remained unpollinated. We propose a model whereby the rapid increase in ACC Ox1 and Ox2 transcript abundance after harvest contributes to increased ethylene production by florets. This ethylene may regulate aspects of postharvest senescence, in particular chlorophyll loss.

Changes in gene expression and tissue composition were investigated during foliar development and natural senescence of asparagus (Asparagus officinalis L.). Three phases in development and senescence of the foliage were characterized: early fern growth, mature fern, and senescence, when a marked loss of chlorophyll, sucrose, and protein occurred and major changes in translatable mRNAs were detected. Transcripts for three asparagus spear harvest-induced cDNA clones, pTIP9, pTIP11, and pTIP12 (G.A. King and K.M. Davies [1992] Plant Physiol 100: 1661-1669), accumulated during natural foliar senescence, suggesting that the underlying regulatory mechanisms may be similar in both developmental situations. We have used our knowledge of asparagus spear physiology, the probable proteins encoded by the cDNA clones, and our fern development data to propose that sugar depletion regulates the accumulation of at least pTIP12 transcripts in senescing asparagus tissue.

Hairy roots of Brassica napus (rape cv. Giant) have been produced that contain the cytosolic glutamine synthetase (GS) gene from Glycine max (soybean). Leaf explants were cocultivated with Agrobacterium rhizogenes strain A4T harbouring the binary vector pLN16. This vector was constructed by inserting a soybean cytosolic GS cDNA into the multiple cloning site of pGA643, placing it under the control of the CaMV promoter. In addition, the T-DNA region of pLN16 contained a NPTII gene for selection of transformed cells. Transgenic hairy roots grew prolifically on hormone-free media containing a selective level of kanamycin. Southern and northern analyses confirmed the presence of soybean GS DNA and transcripts, respectively. These transformed hairy roots also have a greater abundance of the GS polypeptide, approximately 3-6 fold greater GS activity and lower levels of endogenous ammonia. Hairy roots provide a useful system for studying responses to phosphinothricin (PPT). Hairy roots grown in media containing PPT had lower GS activity, greater ammonia accumulation and slower growth than controls. The presence of the soybean GS gene in the hairy roots reduced these PPT-induced effects and resulted in higher GS activity, lower ammonia levels and faster growth than in PPT-treated controls. Greater tolerance of PPT was also seen in shoots regenerated from the hairy roots displaying elevated levels of GS activity.

In order to study vertebral fractures in various study populations, we earlier prepared a database of vertebral dimensions derived from spinal radiographs of 191 normal women seen regularly over 25 years. In this report we have expanded the range of measurements to include vertebral levels T3 to L5. We report means and standard deviations on anterior and posterior heights, on wedge shape and on heights relative to adjacent vertebrae. When one or both of the latter two quantities are 'far' below the mean, a vertebra is called deformed. We also describe a more flexible way of expressing damage using the number of deformed vertebrae, the degree of deformity of individual vertebrae, or the total damage to the entire spine. In assessing damage we use criteria for deformity adjusted to the limits detected by an experienced diagnostician, replacing an earlier approach based on 95% probability limits of normal variation. The normal women from whom these variations are ascertained are a low-prevalence group with respect to vertebral deformity, with prevalence of 2.8%. When the criteria developed from these women were applied to a moderate-prevalence group (37%) the model had a sensitivity of 97%, a specificity of 89% and an accuracy of 92% as regards the identification of subjects with damaged vertebrae. When used epidemiologically for a moderate-prevalence group the model has a known overestimation of 15%. the model is compared with other schemes for identifying vertebral deformities.

A full-length cDNA clone (pTIP27) encoding asparagine synthetase (AS; EC 6.3.5.4) was isolated from a cDNA library prepared from the tip section (apex to 30 mm) of Asparagus officinalis L. spears. The cDNA clone encodes an mRNA of 1978 bp, giving a derived protein of 66.5 kD molecular mass. The derived amino acid sequence is 81% homologous to AS from Pisum sativum. Only low levels of transcript for AS could be detected in growing spears, roots, or ferns. However, AS mRNA levels began to increase in the tips of harvested spears after 2 h at 20 degrees C, and in the other sections of the spear after 4 h, suggesting that all sections of the spear were responding to the same postharvest signal. The results are discussed in relation to metabolic changes occurring in harvested spears.

Changes in mRNA activity in tips of harvested asparagus spears (Asparagus officinalis L.) held in light or dark for up to 48 h at 20 degrees C were investigated as an initial step in elucidating the genetic response of asparagus spears to harvest. Total RNA was isolated from 30-mm tips of spears 180 mm in length at 0, 6, 12, 24, and 48 h after spear harvest and translated in vitro, and translation products were separated using both sodium dodecyl sulfate-polyacrylamide gel electrophoresis and two-dimensional polyacrylamide gel electrophoresis. We detected 25 consistent changes in translatable mRNAs, involving both increase and decrease in mRNA abundance. The majority of the changes occurred within 12 h of harvest. Most of the changes were not light regulated. cDNA libraries were constructed from polyadenylated mRNA extracted from tips of spears at harvest (0 h) and after 12 h in the dark at 20 degrees C. Differential hybridization screening of the cDNA libraries isolated nine cDNA clones whose corresponding transcripts had altered expression after harvest. Investigations of mRNA activity during spear development demonstrated that the changes detected were harvest related. Possible roles for the mRNAs corresponding to the isolated clones in tips of harvested spears are discussed.

Objective: To test whether bone mass increases in healthy nonpregnant white women during early adult life after cessation of linear growth; and to test whether various self-chosen levels of physical activity and nutrient intake or use of oral contraceptives influences this increase in bone mass., Design: Longitudinal prospective study of up to 5 years of 156 healthy college-aged women full-time students attending professional schools in universities in the Omaha, Neb, area., Setting: University medical center., Participants: A convenience sample of healthy women students from Omaha-area professional schools. Any candidate with an illness, condition, or medication (except oral contraceptives) thought to affect general health or bone mass was excluded., Interventions: None., Outcome Measures: Clinical and family histories of disease, particularly osteoporosis; oral contraceptive use; bone mineral densities of the spine, forearm, and total body by dual- and single-photon absorptiometry; estimates of nutrient intake by repeated 7-day diet diaries; and measures of physical activity using a physical activity monitor., Results: The median gain in bone mass for the third decade of life, expressed as a percentage per decade, was 4.8% for the forearm, 5.9% for lumbar bone mineral content, 6.8% for lumbar bone mineral density, and 12.5% for total body bone mass (P < .0001 in all cases). By both bivariate and multiple regression analysis the rate of gain in bone density of the spine was negatively correlated with age and positively correlated with calcium/protein intake ratio and physical activity (multiple r = .31; P = .004). Bivariate analysis showed that use of oral contraceptives was associated with greater gain in total body bone mass (r = .31, P = .01). The estimated age when mineral acquisition ceased ranged from 28.3 years to 29.5 years at the several study sites., Conclusions: Gain in bone mass occurs in healthy young women during the third decade of life. Physical activity and dietary calcium intake both exert a positive effect on this bone gain. Use of oral contraceptives exerts a further independent positive effect. Changes in life-style among college-aged women, involving relatively modest increases in physical activity and calcium intake, may significantly reduce the risk of osteoporosis late in life.

Both retrospectively and prospectively designed studies consistently show low bone mass and/or bone mineral content (BMC) to be risk factor for low-trauma fractures in postmenopausal women. Along with the reports of such studies there has been concern expressed that BMC measurements overlap between fracture groups, i.e., some women with high BMC develop fractures and some women with low BMC do not. In these commonly used epidemiologic study designs, BMC does not discriminate between those who have and have not experienced the untoward event at some level of the exposure factor. The ability to discriminate is more properly determined by the sensitivity and specificity of the measured value. To contrast the concepts of risk and sensitivity, a nested case-control study was conducted within a 24-year cohort study of women at risk for osteoporosis. We found that for each 1.0 decrement of BMC z-scores, the adjusted relative risk for the prospective study design was 1.67, while the odds ratio obtained from the most recent BMC z-score measurements was 1.87. A receiver operating characteristic (ROC) curve, calculated from the nested case-control study data, showed that BMC z-scores, measured after low-trauma fracture, have both low sensitivity and low specificity to detect existing fracture status.

A group of 75 healthy women nearing menopause were entered into a longitudinal study of bone mass and bone cell function. All were at least 46 years, were still menstruating, and had premenopausal levels of follicle stimulating hormone (FSH) and estradiol (E2). Bone density measurements of the spine (dual-photon absorptiometry, DPA) and total-body (DPA) and forearm (single-photon absorptiometry, SPA) were made at 6 month intervals along with measurements of FSH and E2 over an average of 2.04 +/- 0.45 years. The annual rate of change in bone mass was determined for each individual by regressing the bone mass measurement at each site at the time of observation. The slopes were pooled, and the percentage annual change was calculated as the mean slope divided by the initial mean bone mass value. The mean rates of change in bone mass were calculated with and without weighting by length of observation. No meaningful differences in the results were seen in the weighted values compared to the unweighted values, and none of the sites showed a slope significantly different from zero. Demonstrated reproducibility and sample size provided sufficient power to detect annual weighted rates of change of 0.81% for spine BMC, 0.69% for spine BMD, 1.31% for forearm BMC, 1.55% for forearm BMC/BW, and 1.09% for total body bone mineral. We conclude that if changes in bone mineral are occurring in women at this age, they are substantially less than 1%/year for spine and not much more for the forearm or total skeleton.

This paper presents evidence that much of the high rate of age-related height loss in women reported in cross-sectional studies is actually a cohort effect rather than an aging effect. Data from a large cross-sectional study of healthy, white American women indicate that there has been a gain in peak adult height of 1.0 cm per decade for several decades from 1900 through 1965. Data from the HES, HANES I, and HANES II studies concur on this point. By contrast, data from a longitudinal study of 191 healthy white U.S. women show only a trivial rate of decline from peak adult height in the fifth and sixth decades of life. In an unselected population, some apparent height loss with age is probably due to disease processes, such as vertebral collapse. Caution is needed in using aging to interpret differences in height and in height-dependent variables, such as bone density, in cross-sectional studies.

Consistency of intake over time for calcium, phosphorus, protein and energy, as estimated from diet diaries, was studied prospectively in two groups of women. One group provided short-term data (n = 165), and the other, data spanning intervals of up to 20 y (n = 164). Although group average intakes changed little, there was a great deal of individual variation. Even at intervals as short as 6 m, current intake estimates accounted for only about 40% of the variance of intakes at an earlier time. Over longer intervals, the predictive value of one estimate in respect to a second deteriorated even further. Thus, across 5 y, less than 25% of the variance of all four nutrient intakes could be accounted for by current intake. The 95% confidence interval for an estimate of earlier intake based upon a later measurement was more than +/- 700 mg for calcium, the least consistent nutrient. The other three nutrients showed nearly identical interstudy consistency, with uncertainties relative to their respective means being about half as large as for calcium. These data show that accurate longitudinal estimates of intake require continuous, prospective monitoring and that current intake is not a good estimator of past intake for most nutrients, especially for calcium.

Bone mineral measurements of the forearm and spine were made in 63 patients under treatment in the Eating Disorders Program of the University of Nebraska Medical Center, 26 with anorexia nervosa (AN), 11 with bulimia nervosa (BU) and 26 with features of both AN and BU (AN/BU). Comparison was made with a group of 211 normal women of similar age. Spinal bone mineral content (BMC) of L2-4 was 45.1 +/- 5.7 g in the normals, 38.0 +/- 7.5 in the AN's, 40.3 +/- 6.6 g in the AN/BU's and 44.4 +/- 6.9 g in the BU's. The AN and AN/BU averages were both significantly different from normal (p less than 0.0005), but the BU average was not. BMC was correlated with body weight in each group and weakly correlated with age in the patients under age 30 in the AN and AN/BU groups combined. Forearm bone mineral measurements in the AN's and AN/BU's were also significantly lower than normal, but the differences were not as great as for the spine. We conclude that bone mineral is reduced in these patients, severely in some of them, and that reduced body weight plays a role. Menstrual disturbances, inhibition of growth and development, and malnutrition remain open as causal factors. Potential for recovery from reduced bone mineral was not demonstrated in this study.

A total of 568 lateral spine radiographs of 191 generally healthy white perimenopausal women were used to determine the limits of normal for shape and dimensions of the vertebral bodies most often involved in osteoporotic fracture. Anterior and posterior vertebral heights for T7-L4 were used to compute wedge shape, relative posterior height, and relative serial change. Wedge shape was defined as anterior height minus posterior height divided by posterior height. Relative posterior height was defined as the posterior height of a vertebra minus the posterior height of the vertebra superior divided by the posterior height of the vertebra superior. The degree of normal wedging depended on position: wedge values progressed down the spine, from a mean of -0.106 at T7 to 0.048 at L4. The minimum normal wedge value ranged from -0.209 at T7 to -0.083 at L4. Radiographs on a cohort of 28 osteoporotic women were evaluated both by ordinary clinical reading of the radiographs and by using the standards developed from the normal subjects. Initial agreement between the two modes of assessment was 85.4%, and in resolving the remaining disagreements the clinician agreed that he had initially misread the films in all but 3.2%. On the basis of this limited experience, we conclude that the use of such objective standards, in a computer-operated algorithm, is more accurate than routine radiographic assessment. Serial x-rays spanning a 15-20 year period in these women permitted determination of both reproducibility and longitudinal change in vertebral dimensions in the perimenopause. The mean relative serial change was not significantly different from zero for all vertebrae.(ABSTRACT TRUNCATED AT 250 WORDS)

Changes in gene expression during foliar senescence and fruit ripening in tomato (Lycopersicon esculentum Mill.) were examined using in-vitro translation of isolated RNA and hybridization against cDNA clones.During the period of chlorophyll loss in leaves, changes occurred in mRNA in-vitro translation products, with some being reduced in prevalence, whilst others increased. Some of the translation products which changed in abundance had similar molecular weights to those known to increase during tomato fruit ripening. By testing RNA from senescing leaves against a tomato fruit ripening-related cDNA library, seven cDNA clones were identified for mRNAs whose prevalence increased during both ripening and leaf senescence. Using dot hybridization, the pattern of expression of the mRNAs corresponding to the seven clones was examined. Maximal expression of the majority of the mRNAs coincided with the time of greatest ethylene production, in both leaves and fruit. Treatment of mature green leaves or unripe fruit with the ethylene antagonist silver thiosulphate prevented the onset of senescence or ripening, and the expression of five of the seven ripening- and senescence-related genes.The results indicate that senescence and ripening in tomato involve the expression of related genes, and that ethylene may be an important factor in controlling their expression.

Transilial bone biopsies were obtained from 34 healthy postmenopausal women following in vivo fluorochrome labeling. Stained and unstained undecalcified sections were evaluated using a Merz grid. Standard histomorphometric data from cancellous bone tissue were collected and the results were evaluated and presented as variables commonly used in bone histomorphometry. The normal ranges, medians, means, and standard deviations for the group of 34 are presented in tabular form for structural, surface, basic dynamic, and derived dynamic data. Similar data for individuals grouped by ages 45-54, 55-64, and 65-74 are also presented. Secular trends for the whole group are evaluated. The structural and surface data are not much different from previous reports of sudden-death accident victims, when methodologic differences are considered. The mineral apposition rate (MAR) was 0.53 +/- 0.08 micron/day, similar to previous reports in cancellous bone, but one-third less than in cortical bone. MAR showed a marked decline with age. In contrast, the extent of tetracycline-labeled surfaces varied widely without a secular trend. Double-label surface (dLS/BS) ranged from 0.5 to 8.0% and single-label surface (sLS/BS), from 0.5 to 10.5%. Mineralizing osteoid surface (MS/OS) varied from 2 to 64%. Using only double-label surface to represent mineralizing surface, volume-based bone formation rate (BFR/BV) ranged from 0.7 to 28%/yr, and the remodeling period (Rm.P) varied from 0.28 to 4.5 years. Calculations using other representations of mineralizing surface [double plus one-half single label (MS/BS"); all label (MS/BS')] are also presented. These bone histomorphometric data are important because: (1) they come from a cohort of living subjects that was recruited solely for the purpose of establishing normal bone histomorphometry; (2) they represent the age range of patients with postmenopausal osteoporosis; and (3) they markedly expand the bone histomorphometric database of healthy persons given in vivo fluorochrome labeling prior to transilial biopsy.