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Background: As the transformation process can induce mutations in host plants, molecular characterization of the associated genomic changes is important not only for practical food safety but also for understanding the fundamental theories of genome evolution., Objectives: To investigate a population-scale comparative study of the genome-wide spectrum of sequence variants in the transgenic genome with the variations present in 3000 rice varieties., Results: On average, we identified 19,273 SNPs (including Indels) per transgenic line in which 10,729 SNPs were at the identical locations in the three transgenic rice plants. We found that these variations were predominantly present in specific regions in chromosomes 8 and 10. Majority (88%) of the identified variations were detected at the same genomic locations as those in natural rice population, implying that the transgenic induced mutations had a tendency to be common alleles., Conclusion: Genomic variations in transgenic rice plants frequently occurred at the same sites as the major alleles found in the natural rice population, which implies that the sequence variations occur within the limits of a biological system to ensure survival.

Objective: To examine the association between state-level tobacco control measures and current use estimates of both e-cigarettes and cigarettes, while accounting for socio-demographic correlates., Methods: Using the 2012-2013 and 2013-2014 National Adult Tobacco Survey (NATS), we assessed prevalence estimates of US adults' e-cigarette and cigarette current use. Four state groups were created based on the combined state-specific prevalence of both products: low cigarette/e-cigarette (n = 15), high cigarette/e-cigarette (n = 16), high cigarette/low e-cigarette (n = 11), and low cigarette/high e-cigarette) (n = 9). To evaluate the implementation of state-level tobacco control measures, Tobacco Control Index (TCI) was calculated using the State of Tobacco Control annual reports for 2012 and 2013. Multinomial logistic regression models were used to examine differences among the four groups on socio-demographic factors and TCI. Low cigarette/e-cigarette group was used as the referent group., Results: Current use estimates of each product varied substantially by state; current e-cigarette use was highest in Oklahoma (10.3%) and lowest in Delaware (2.7%), and current cigarette use was highest in West Virginia (26.1%), and lowest in Vermont (12.6%). Compared to low cigarette/e-cigarette, all other US-state categories had significantly lower TCI scores (high cigarette/e-cigarette: adjusted Relative Risk Ratio [aRRR] = 0.61; 95% confidence interval [CI]: 0.60-0.61, high cigarette/low e-cigarette: aRRR = 0.74; 95% CI: 0.73-0.74, and low cigarette/high e-cigarette: aRRR = 0.72; 95% CI: 0.71-073)., Conclusions: Enforcing existing tobacco control measures likely interacts with e-cigarette use despite being cigarette-focused. Continuing to monitor e-cigarette use is critical to establish baseline use and evaluate future e-cigarette specific federal and state-level tobacco regulatory actions while accounting for the existing tobacco control environment., Implications: This study investigates state-level current use estimates of e-cigarettes and cigarettes among US adults; and their association with four existing tobacco control measures. The overall score of these measures was negatively associated with state-level current use estimates such that states with low current e-cigarette and cigarette use had the highest mean overall score. This study assesses the potential relationship between existing state-level tobacco control measures and e-cigarette use and calls for improving the enforcement of the known-to-work tobacco control measures across all US states, while developing evidence-based regulations and interventions specific to e-cigarettes within the existing US tobacco use environment.

Men who have sex with men (MSM) commonly use inhaled nitrites, or poppers, though their use is a risk factor HIV seroconversion. Pre-exposure prophylaxis, or PrEP, is effective for HIV prevention, but is not widely used, and little is known regarding PrEP use and acceptability among MSM who use inhaled nitrites. We surveyed 580 MSM in Paris, France in 2016 about popper use, sexual behaviors including condomless anal intercourse (CAI), serosorting, and sexual positioning, PrEP use, PrEP candidacy, and interest in alternate PrEP delivery modalities. We included 444 HIV negative participants for the current study. 46.2% reported popper use in the prior 3 months. Using multivariate adjusted logistic regression, we found that popper users were more likely than non-users to consider themselves candidates for PrEP [adjusted relative risk ratio (aRRR) = 2.73; 95% CI 1.54-4.83], but they were not more likely to be current (aRRR = 1.54; 95% CI 0.71-3.33) or past (aRRR = 1.37; 95% CI 0.44-4.28) PrEP users. Mediation analyses indicated that increased CAI and serosorting partly explained the relationship between popper use and PrEP candidacy. There was considerable interest in alternate proposed PrEP delivery modalities, particularly long-acting injectable PrEP [adjusted risk ratio (aRR) = 1.43; 95% CI 1.15-1.79].

Objective: The objective of this study was to examine the association between perceived stress and sleep health among a sample of sexual minority men (SMM)., Design: Cross-sectional survey., Setting: Paris, France., Participants: Gay, bisexual and other SMM users ≥18 years on a geosocial networking application in Paris, France (N = 580)., Measurements: Participants were directed to a web-based survey measuring stress, sleep health, and socio-demographics. Multivariate log-binomial regression models were used to estimate the adjusted risk ratios (aRRs) and 95% confidence intervals (CIs) to examine how stress may affect different dimensions of sleep health: 1) poor sleep quality, 2) short sleep duration, 3) problems falling asleep, and 4) problems staying awake in the daytime., Results: Most participants (69.9%) reported at least sometimes feeling stressed (compared to never or rarely). Additionally, results demonstrate that higher perceived stress was associated with poorer sleep health; compared with those who reported feeling stress never or rarely, those who felt stress sometimes, often, or always were more likely to experience poor sleep quality (aRR = 6.67; 95% CI = 3.61-12.3), short sleep duration (aRR = 1.67; 95% CI = 1.17-2.38), problems falling asleep (aRR = 3.20; 95% CI = 2.26-4.52), and problems staying awake during the daytime (aRR = 3.52; 95% CI = 1.64-7.53)., Conclusion: Elevated perceived stress can negatively influence sleep health among SMM in Paris, France., (Copyright © 2018 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.)

While research increasingly studies how neighborhood contexts influence HIV among gay, bisexual and other men who have sex with men (MSM) populations, to date, no research has used global positioning system (GPS) devices, an innovative method to study spatial mobility through neighborhood contexts, i.e., the environmental riskscape, among a sample of Black MSM. The purpose of this study was to examine the feasibility of collecting two-week GPS data (as measured by a pre- and post-surveys as well as objectively measured adherence to GPS protocol) among a geographically-diverse sample of Black MSM in the Deep South: Gulfport, MS, Jackson, MS, and New Orleans LA (n = 75). GPS feasibility was demonstrated including from survey items, e.g. Black MSM reported high ratings of pre-protocol acceptability, ease of use, and low levels of wear-related concerns. Findings from this study demonstrate that using GPS methods is acceptable and feasible among Black MSM in the Deep South.

Background: Understanding where and how young black men who have sex with men (YBMSM) in the southern United States meet their sexual partners is germane to understanding the underlying factors contributing to the ongoing HIV transmission in this community. Men who have sex with men (MSM) commonly use geosocial networking apps to meet sexual partners. However, there is a lack of literature exploring geosocial networking app use in this particular population., Objective: Our aim was to examine the characteristics, preferences, and behaviors of a geographically diverse sample of geosocial networking app-using YBMSM in the southern United States., Methods: Data were collected from a sample of 75 YBMSM across three cities (Gulfport, Mississippi; Jackson, Mississippi; and New Orleans, Louisiana). Multiple aspects of geosocial networking app use were assessed, including overall app use, age of participant at first app use, specific apps used, reasons for app use, photos presented on apps, logon times and duration, number of messages sent and received, and characteristics of and behaviors with partners met on apps. Survey measures of app-met partner and sexual behavior characteristics assessed at midpoint (Day 7) and completion visits (Day 14) were compared using McNemar's test or Wilcoxon signed-rank test. In addition, we assessed activity spaces derived from GPS devices that participants wore for 2 weeks., Results: Of the 70 participants who responded to the overall app-use item, almost three-quarters (53/70, 76%) had ever used geosocial networking apps. Jack'd was the most commonly used geosocial networking app (37/53, 70%), followed by Adam4Adam (22/53, 42%), and Grindr (19/53, 36%). The mean and median number of apps used were 4.3 (SD 2.7) and 4.0 (range 0-13), respectively. Most app-using participants displayed their face on the profile picture (35/52, 67%), whereas fewer displayed their bare legs (2/52, 4%) or bare buttocks (or ass; 2/52, 4%). The mean age at the initiation of app use was 20.1 years (SD 2.78) ranging from 13-26 years. Two-thirds (35/53, 66%) of the sample reported using the apps to "kill time" when bored. A minority (9/53, 17%) reported using the apps to meet people to have sex/hook up with. The vast majority of participants reported meeting black partners for sex. Over two-thirds (36/53, 68%) reported that the HIV status of their app-met partners was negative, and 26% (14/53) reported that they did not know their partner's HIV status. There was a significant difference in GPS activity spaces between app using YBMSM compared to nonapp using YBMSM (2719.54 km 2 vs 1855.68 km 2 , P=.011)., Conclusions: Use of geosocial networking apps to meet sexual partners among our sample of YBMSM in the southern United States was common, with a diverse range of app use behaviors being reported. Further research should characterize the association between geosocial networking app use and engagement in sexual behaviors that increase risk for HIV acquisition and transmission. In addition, geosocial networking apps present a promising platform for HIV prevention interventions targeting YBMSM who use these apps., (©Dustin T Duncan, Su Hyun Park, H. Rhodes Hambrick, Derek T Dangerfield II, William C Goedel, Russell Brewer, Ofole Mgbako, Joseph Lindsey, Seann D Regan, DeMarc A Hickson. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 14.06.2018.)

Rectal douching is a common but potentially risky practice among MSM; MSM who douche may be ideal candidates for rectal microbicides as HIV prevention. Herein we explored rectal douching and its association with condomless receptive anal intercourse (CRAI), group sex, rates of HIV and other STIs, and likelihood to use rectal microbicide gels. We recruited a sample of 580 MSM from a geosocial-networking smartphone application in Paris, France in 2016. Regression models estimated adjusted risk ratios (aRRs) for associations between rectal douche use and (1) engagement in CRAI, (2) group sex, (3) self-reported HIV and STI diagnoses, and (4) likelihood to use rectal microbicide gels for HIV prevention. 54.3% of respondents used a rectal douche or enema in the preceding 3 months. Douching was significantly associated with CRAI (aRR: 1.77), participation in group sex (aRR: 1.42), HIV infection (aRR: 3.40), STI diagnosis (aRR: 1.73), and likelihood to use rectal microbicide gels (aRR: 1.78). Rectal douching is common among MSM, particularly those who practice CRAI, and rectal microbicide gels may be an acceptable mode of HIV prevention for MSM who use rectal douches.

The objective of this study was to examine the association between financial hardship, condomless anal intercourse and HIV risk among a sample of men who have sex with men (MSM). Users of a popular geosocial networking application in Paris were shown an advertisement with text encouraging them to complete a anonymous web-based survey (n = 580). In adjusted multivariate models, high financial hardship (compared to low financial hardship) was associated with engagement in condomless anal intercourse (aRR 1.28; 95% CI 1.08-1.52), engagement in condomless receptive anal intercourse (aRR 1.34; 95% CI 1.07-1.67), engagement in condomless insertive anal intercourse (aRR 1.30; 95% CI 1.01-1.67), engagement in transactional sex (aRR 2.36; 95% CI 1.47-3.79) and infection with non-HIV STIs (aRR 1.50; 95% CI 1.07-2.10). This study suggests that interventions to reduce financial hardships (e.g., income-based strategies to ensure meeting of basic necessities) could decrease sexual risk behaviors in MSM.

Purpose: In this retrospective cohort study we assessed the effect on prostate specific antigen concentration of low dose finasteride or dutasteride treatment for male androgenetic alopecia in men with baseline serum prostate specific antigen less than 2.5 ng/ml., Materials and Methods: The cohort consisted of 1,379 consecutive male patients who were treated for androgenetic alopecia with finasteride 1.25 mg daily or dutasteride 0.5 mg every 3 days in 2002 to 2012 and who underwent prostate specific antigen measurements at baseline and at least once thereafter. Patients in whom baseline or followup prostate specific antigen after prescription exceeded 2.5 ng/ml were excluded from study to rule out men with a higher likelihood of prostate cancer. Patients were stratified according to age, baseline prostate specific antigen, medication type and treatment duration., Results: Overall low dose 5α-reductase inhibitor treatment reduced prostate specific antigen by 27.8% relative to baseline. Of the patients 1,094 (79.3%) showed prostate specific antigen decreases (average 40.8%). In the remaining 285 patients (20.7%) prostate specific antigen was stable or increased (average 24.2% increase). Closer analysis largely showed that only men with baseline prostate specific antigen 0.5 ng/ml or greater had a treatment related prostate specific antigen reduction. On multivariate logistic analysis low baseline prostate specific antigen was significantly associated with stable/increased prostate specific antigen. Low dose dutasteride and finasteride reduced prostate specific antigen to similar degrees (31.1% and 25.1%, respectively). A marked prostate specific antigen decrease of 26.0% was observed even after short-term treatment (3 to 6 months)., Conclusions: Dutasteride and finasteride reduced prostate specific antigen to similar degrees. This effect was observed soon after commencing treatment. In patients with low baseline prostate specific antigen the levels could remain stable or even increase. These findings are limited to men with baseline prostate specific antigen less than 2.5 ng/ml., (Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Objective: To investigate the state-specific prevalence, regional differences, and correlates of hookah use among U.S. adults., Methods: We analyzed the most recent nationally representative data of adults from the National Adult Tobacco Survey (NATS) 2012-2013 (n = 60192). State-specific prevalence of lifetime and current hookah use was calculated and mapped. Multivariate logistic regression was performed to determine the association between sociodemographic characteristics, regional differences, and hookah use., Results: Among U.S. adults (≥18 years), overall prevalence of lifetime hookah use was 12.3%, while current use was 3.9%. Mapping of state-specific prevalence revealed that the West tended to have higher rates of use, while the South tended to have lower ones. In the adjusted model, we observed that current hookah use was positively associated with younger adults, males, non-Hispanic adults, those with higher education and income statuses, being single, those living in the West, and current cigarette use., Conclusion: The prevalence of hookah use varies by state, region, and sociodemographic characteristics among adults. Future research, including longitudinal studies, are needed to identify geographic and sociodemographic characteristics and trends among hookah users, investigate hookah-related health outcomes, and evaluate targeted public health efforts aimed at this emerging threat., Implications: This study investigates state-level prevalence, regional differences, and sociodemographic characteristics of hookah use among U.S. adults, using the most recent NATS. Hookah use was positively associated with younger adults and those living in the West. This study adds to the understanding of the geographic and sociodemographic factors underlying hookah use, which can be used to develop much needed evidence-based regulations and programs that are responsive to the needs of different risk groups., (© The Author 2016. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: To examine whether household food insecurity is associated with serious psychological distress (SPD) in fathers and mothers in a nationally representative US sample., Methods: We analyzed cross-sectional, matched child-parent data from the 2014 to 2015 National Health Interview Survey (N = 18,456). Parental psychological distress was assessed using the Kessler-6 (K-6) scale. Family food security was measured using the USDA's 10-item Food Security scale, and households were dichotomized as food secure or food insecure. Multivariate logistic regression analyses were performed to examine associations between SPD and food insecurity stratified by parental status (mother/father), controlling for sociodemographic factors., Results: One hundred forty-seven (2.0%) fathers, 444 (3.9%) mothers, and 591 (3.2%) of all parents had K-6 scores indicating SPD. A total of 2414 (13.1%) parents reported being food insecure, including 750 (10.4%) fathers and 1664 (14.8%) mothers. In multivariate analyses, food insecurity was significantly associated with SPD both among fathers and mothers (odds ratio [OR] = 4.2; 95% confidence interval [CI], 2.4-7.3 and OR = 2.6; 95% CI, 1.9-3.5, respectively)., Conclusion: This is the first study we are aware of to demonstrate that food insecurity is independently associated with SPD among fathers and mothers, and that fathers may be at higher risk of SPD than mothers in food insecure homes. These findings highlight the need to assess and treat the mental health of fathers, a historically underrepresented group in the fields of mental health and pediatrics, in addition to mothers, in food insecure homes.

Previous evidence suggests the potential for adverse effects of persistent organic pollutants (POPs) on metabolic health even at low-dose exposure levels common among the general population, but there is less evidence of these associations among children. Therefore, as part of a prospective cohort study, 214 children were measured for POPs exposure. After the 1-year follow-up, we assessed the effect of circulating POPs exposure among 158 children aged 7-9 years (at baseline) on the change of metabolic components of metabolic syndrome using multiple regression analysis. In addition, we calculated the continuous metabolic syndrome (cMetS) score and assessed the variation among individuals by POPs exposure. The concentrations of marker polychlorinated biphenyls (PCBs) were significantly associated with increased change in diastolic blood pressure (BP) and triglyceride levels during a 1-year follow-up, after controlling for sex, age, household income, and change in body mass index. Total PCBs also showed a marginal association with increasing cMetS score from the baseline. Of the metabolic components, change in diastolic BP over time showed a notable association with specific PCBs, but no association with organochlorine pesticides. Here, we found that low-dose exposures to PCBs among children in the general population could negatively influence metabolic health, particularly diastolic BP. Increased disease sensitivity during childhood can continue to adulthood, thus, these results support the need for continuous assessment of the health impact of POPs.

Although children are more vulnerable than adults to environmental hazards, due to their physiological and behavioral characteristics, few studies have assessed their internal exposure to persistent organic pollutants (POPs). The objective of this study was to determine the serum levels of certain polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) among pre-pubertal children in Korea and examine their variation with age and gender. We analyzed a total of 51 POPs in 214 children (age range, 7-9 years), using data from the Ewha Birth and Growth Cohort Study. To examine change over time, POP concentrations were measured at both 7 and 9 years of age in a sub-cohort of 26 children. The median and interquartile range (IQR, 25th to 75th percentiles) data for the sum of PCB congeners was 26.44 ng/g lipid (18.27-37.63 ng/g lipid). The median (IQR) concentration for the sum of OCPs was 74.82 ng/g lipid (51.11-112.45 ng/g lipid). Our results showed significant increases in serum concentrations of total PCBs with age (p = 0.0001), no gender dependence of total PCBs (p = 0.38) and total OCPs (p = 0.12), and strong correlations between individual POPs. Childhood exposure to POPs was relatively low compared to other studies carried out in different countries. However, even though the use of POPs has been banned since 2001, our results indicated that children in the general population are still exposed to various POPs. Because long-term, low-level exposure to POPs in the general population remains a concern for human health, future research should examine major routes of exposure and identification of risk factors.

TGF-β regulates pleiotropic cellular responses including cell growth, differentiation, migration, apoptosis, extracellular matrix production, and many other biological processes. Although non-Smad signaling pathways are being increasingly reported to play many roles in TGF-β-mediated biological processes, Smads, especially receptor-regulated Smads (R-Smads), still play a central mediatory role in TGF-β signaling for epithelial-mesenchymal transition. Thus, the biological activities of R-Smads are tightly regulated at multiple points. Inhibitory Smad (I-Smad also called Smad7) acts as a critical endogenous negative feedback regulator of Smad-signaling pathways by inhibiting R-Smad phosphorylation and by inducing activated type I TGF-β receptor degradation. Roles played by Smad7 in health and disease are being increasingly reported, but the molecular mechanisms that regulate Smad7 are not well understood. In this study, we show that E3 ubiquitin ligase Itch acts as a positive regulator of TGF-β signaling and of subsequent EMT-related gene expression. Interestingly, the Itch-mediated positive regulation of TGF-β signaling was found to be dependent on Smad7 ubiquitination and its subsequent degradation. Further study revealed Itch acts as an E3 ubiquitin ligase for Smad7 polyubiquitination, and thus, that Itch is an important regulator of Smad7 activity and a positive regulator of TGF-β signaling and of TGF-β-mediated biological processes. Accordingly, the study uncovers a novel regulatory mechanism whereby Smad7 is controlled by Itch.

In this study, we investigated whether natural products including coixol derived from Coix Lachryma-Jobi var. ma-yuen affect MUC5AC mucin gene expression, production and secretion from airway epithelial cells. Confluent NCI-H292 cells were pretreated with oleic acid, linoleic acid, glyceryl trilinoleate, beta-stigmasterol or coixol for 30 min and then stimulated with PMA (phorbol 12-myristate 13-acetate), EGF (epidermal growth factor) or TNF-α (tumor necrosis factor-α) for 24 h. The MUC5AC mucin gene expression, mucin protein production and secretion were measured by RT-PCR and ELISA. The results were as follows: (1) Oleic acid, linoleic acid, glyceryl trilinoleate, beta-stigmasterol and coixol inhibited the expression of MUC5AC mucin gene induced by PMA from NCI-H292 cells; (2) Oleic acid, linoleic acid, glyceryl trilinoleate, beta-stigmasterol and coixol also inhibited the production of MUC5AC mucin protein induced by the same inducers from NCI-H292 cells; (3) Coixol inhibited the expression of MUC5AC mucin gene and production of MUC5AC mucin protein, induced by EGF or TNF-α from NCI-H292 cells; (4) Coixol decreased PMA-induced MUC5AC mucin secretion from NCI-H292 cells. This result suggests that coixol, the characteristic component among the examined five natural products derived from C. Lachryma-Jobi var. ma-yuen, can regulate gene expression, production and secretion of mucin, by directly acting on airway epithelial cells.

Background: It is valuable to find the potential activity of regulating the excessive mucin secretion by the compounds derived from various medicinal plants. We investigated whether aqueous extract of the root bark of Morus alba L. (AMA), kuwanon E, kuwanon G, mulberrofuran G, and morusin significantly affect the secretion and production of airway mucin using in vivo and in vitro experimental models., Methods: Effect of AMA was examined on hypersecretion of airway mucin in sulfur dioxide-induced acute bronchitis in rats. Confluent NCI-H292 cells were pretreated with ethanolic extract, kuwanon E, kuwanon G, mulberrofuran G, or morusin for 30 minutes and then stimulated with phorbol 12-myristate 13-acetate (PMA) for 24 hours. The MUC5AC mucin secretion and production were measured by enzyme-linked immunosorbent assay., Results: AMA stimulated the secretion of airway mucin in sulfur dioxide-induced bronchitis rat model; aqueous extract, ethanolic extract, kuwanon E, kuwanon G, mulberrofuran G and morusin inhibited the production of MUC5AC mucin induced by PMA from NCI-H292 cells, respectively., Conclusion: These results suggest that extract of the root bark and the natural products derived from Morus alba L. can regulate the secretion and production of airway mucin and, at least in part, explains the folk use of extract of Morus alba L. as mucoregulators in diverse inflammatory pulmonary diseases.

There is currently a shortage of efficient promoters for stress-inducible gene expression, especially in monocotyledonous crops. Here, we report analysis of the rice Wsi18 promoter, a member of the group 3 Lea family, in transgenic rice plants. The abundance of Wsi18 mRNA increased in leaf tissues within 2 h of exposure to NaCl or abscisic acid (ABA) and within 6 h of exposure to drought, but there was no transcript increase in response to low-temperature conditions. Wsi18 mRNA accumulated in the roots similarly to in the leaves, but at a faster rate. The promoter was linked to the GFP reporter gene, transformed into rice, and its activity was analyzed in transgenic plants at all stages of plant growth from calli, vegetative tissues, flowers, and to dry seeds, both before and after stress treatment. The activity of the promoter was significantly increased in the whole plant body, including flowers, on exposure of plants to stress conditions, with very low levels of basal activity in all tissues. Moreover, the promoter was found to be predominantly active in the whole grain, including endosperm, embryo, and aleurone layer during seed development. Together, we have identified and analyzed the Wsi18 promoter and found a previously undescribed characteristic-a stress-inducible property in the whole plant body with activity in the whole grain during seed development.

Many aspects of epigenetic phenomena have been elucidated via studies of transposable elements. An active transposable element frequently loses its ability to mobilize and goes into an inactive state during development. In this study, we describe the cyclic activity of a maize transposable element dissociation (Ds) in rice. In rice genome, Ds undergoes the spontaneous loss of mobility. However, an inactive state of Ds can be changed into an active state during tissue culture. The recovery of mobility accompanies not only changes in the methylation patterns of the terminal region of Ds, but also alteration in the steady state level of the activator (Ac) mRNA that is expressed by a constitutive CaMV 35S promoter. Furthermore, the Ds-reactivation process is not random, but stage-specific during plantlet regeneration. Our findings have expanded previous observations on Ac reactivation in the tissue culture of maize.