Bt Maize Seed Mixtures for Helicoverpa zea (Lepidoptera: Noctuidae): Larval Movement, Development, and Survival on Non-transgenic Maize.

In 2012 and 2013, field trials were conducted near Rosemount, MN, to assess the movement and development of Helicoverpa zea (Boddie) larvae on non-Bt refuge corn plants within a seed mixture of non-Bt and Bt corn. The Bt corn hybrid expressed three Bt toxins-Cry1Ab, Cry1F, and Vip3A. As the use of seed mixtures for insect resistance management (IRM) continues to be implemented, it is necessary to further characterize how this IRM approach impacts resistance development in ear-feeding Lepidopteran pests. The potential for Bt pollen movement and cross pollination of the non-Bt ears in a seed mixture may lead to Bt toxin exposure to larvae developing on those refuge ears. Larval movement and development by H. zea, feeding on non-Bt refuge plants adjacent to either transgenic Bt or non-Bt plants, were measured to investigate the potential for unintended Bt exposure. Non-Bt plants were infested with H. zea eggs and subplots were destructively sampled twice per week within each treatment to assess larval development, location, and kernel injury. Results indicate that H. zea larval movement between plants is relatively low, ranging from 2-16% of larvae, and occurs mainly after reaching the second instar. Refuge plants in seed mixtures did not produce equivalent numbers of H. zea larvae, kernel injury, and larval development differed as compared with a pure stand of non-Bt plants. This suggests that there may be costs to larvae developing on refuge plants within seed mixtures and additional studies are warranted to define potential impacts.

Transcript analysis and comparative evaluation of shaker and slowmo gene homologues from the European corn borer, Ostrinia nubilalis.

The movement and dispersal of larval Lepidoptera impact their survival and distribution within the natural landscape. Homologues of the Drosophila behaviour-linked genes shaker (shkr) and slowmo (slmo) were identified from Ostrinia nubilalis (Lepidoptera: Crambidae). Onshkr was isolated as a 1610-nucleotide (nt) constitutively expressed transcript encoding a membrane-localized 469-amino-acid (aa) protein with a conserved tetramerization domain and the six-domain architecture necessary for the molecule to fold into an active K(+) channel. Three expressed splice variants of 682, 970 and 1604 nt were identified for the Onslmo gene, and encode predicted 141 and 228 aa proteins with a conserved protein of relevant evolutionary and lymphoid interest (PRELI) domain that may function in mitochondrial protein sorting and perinuclear protein localization. Onshkr and Onslmo protein sequences aligned within monophyletic lepidopteran groups.

Modeling the impact of cross-pollination and low toxin expression in corn kernels on adaptation of European corn borer (Lepidoptera: Crambidae) to transgenic insecticidal corn.

We used a mathematical model with processes reflecting larval mortality resulting from feeding on cross-pollinated ears or Bt ears of corn to analyze the risk of evolution of Cry-toxin resistance in Ostrinia nubilalis (Hübner). In the simulations, evolution of resistance was delayed equally well by both seed mixtures and blocks with the same proportion of refuge. Our results showed that Bt-pollen drift has little impact on the evolution of Bt resistance in O. nubilalis. However, low-toxin expression in ears of transgenic corn can reduce the durability of transgenic corn expressing single toxin, whereas durability of pyramided corn hybrids is not significantly reduced. The toxin-survival rate of heterozygous larvae in Bt-corn ears expressing one or two proteins has more impact on evolution of Bt resistance in O. nubilalis than the parameters related to larval movement to Bt ears or the toxin-survival rate of the homozygous susceptible larvae in Bt ears. Bt resistance evolves slower when toxin mortality is distributed across the first two larval stadia than when only the first instars are susceptible to Bt toxins. We suggest that stakeholders examine toxin-survival rates for insect pests and take into account that instars may feed on different parts of Bt corn.

Effectiveness of post card appointment reminders.

OBJECTIVE: This study measures the effectiveness of post card appointment reminders in a residency-based family practice center. METHODS: Outcomes of 1,380 consecutive appointments before institution of reminders were compared with 1,303 appointments afterward. Then, 140 patients were informally surveyed in follow-up. RESULTS: Before reminders, overall office no-show rate was 13.0%, cancellations were 19.4%, and arrivals were 67.6%. No-shows correlated with length of time from scheduling date to appointment date, seeing a resident rather than faculty, and patient payment classification (p < 0.0001). Post card reminders did not significantly improve arrivals by patients or change no-shows to cancellations. The reminders were well received by patients. CONCLUSIONS: Post card appointment reminders were simple to institute and appreciated by patients but had little effect on improving appointment-keeping behavior.

Attention-deficit hyperactivity disorder. Management by family physicians.

OBJECTIVE: To assess the evaluation and treatment practices of family physicians in regard to attention-deficit hyperactivity disorder (ADHD). DESIGN, SETTING, AND PARTICIPANTS: A 20-item survey was developed and mailed to all 940 family and general physicians in Kansas. MAIN OUTCOME MEASURES: Physician practices regarding ADHD. RESULTS: The 471 respondents (50.1%) included 386 physicians in private clinical practice, who constituted the study group. Ninety-eight percent of these physicians regularly saw children and over half suspected four or more cases of ADHD in the past year. When suspecting ADHD, 43% of the physicians referred for diagnosis and treatment; 30% evaluated and treated by themselves; and 27% referred for evaluation but did follow-up treatment themselves. There was no significant difference in these ratios between rural and urban physicians. Family physicians referred to a pediatric psychiatrist most often, with no apparent difference in referral pattern by community size; 75% indicated they were comfortable with their current referral support. Of the physicians who diagnosed and treated ADHD themselves, only 30.6% routinely ordered laboratory work or other tests, only 28.7% used teacher questionnaires, and only 20.4% used parent questionnaires. CONCLUSIONS: An important amount of patient care for ADHD is managed by family physicians, without significant differences between rural and urban practices. Most family physicians are satisfied with their current level of referral support. Physicians who treat ADHD themselves usually rely on clinical evaluation rather than special tests or standardized questionnaires.

The effect of bran on bowel function in constipation.

Bran is widely used to treat a variety of gastrointestinal disorders. With few exceptions, investigative work has focused on the effect of bran in normal subjects. Despite its widespread use, there have been no systematic studies of bran in constipation. Wheat bran is the "gold standard" because no other natural fiber has yet been shown to be as effective in increasing fecal bulk. We evaluated the effect of two brans, wheat and corn (20 g/day), on fecal weight, fecal moisture content, bowel movement frequency, intestinal transit time, and symptoms in 10 constipated (less than or equal to 3 movements/wk) but otherwise healthy women. The administration of bran was associated with a significant increase in fecal weight (157%), bowel movement frequency (55%), and decrease in intestinal transmit time (50%). Percentage fecal moisture increased only with wheat bran (67.4-72.1%), whereas corn bran was significantly better than wheat bran in relieving symptoms of constipation.

Smokers over age 35 continue to receive oral contraceptives. Survey of patients in a family practice residency practice.

OBJECTIVE: To assess the frequency with which women over age 35 report both current oral contraceptive use and current cigarette smoking. DESIGN: Cross-sectional survey of women in a single practice setting. SETTING: Primary care teaching practice in a mid-sized US city. PATIENTS: 142 women aged 35-55 who had not reached menopause and had not had hysterectomy. MAIN OUTCOME MEASURES: Smoking status in current oral contraceptive users. RESULTS: 19 women (13%) were current oral contraceptive users and 46 (32%) were current smokers. Four of the oral contraceptive users (21%) reported current smoking. CONCLUSIONS: Despite reported cardiovascular risk, women who smoke continue to receive prescriptions for oral contraceptives. Physicians should redouble efforts to record smoking status and offer smoking cessation treatment to women over age 35 who smoke and wish to take oral contraceptives.

The effect of age at smoking initiation on lung cancer risk.

It has been assumed that a younger age at initiation of cigarette smoking is associated with an increased risk of lung cancer, but previous studies have not adjusted for two strong risk factors, the amount smoked and duration smoked. We used data from a population-based case-control study with 282 histologically confirmed lung cancer cases matched to 3,282 random controls to determine whether age at initiation of smoking plays an independent role in the occurrence of lung cancer. After controlling for age, sex, and amount of tobacco exposure, men who began to smoke before age 20 had a substantially higher risk of developing lung cancer [odds ratio (OR) = 12.7; 95% confidence interval (CI) = 6.39-25.2] compared with men who began smoking at age 20 or older (OR = 6.03; 95% CI = 2.82-12.9). For women, the heavy increase in risk continued until age 25 (OR = 9.97; 95% CI = 4.68-21.2) compared with women who began smoking at age 26 or older (OR = 2.58; 95% CI = 0.53-12.4). There was no predisposition toward a specific histologic type of lung cancer. In this study, up to 52.4% of lung cancer cases in men and up to 73.0% of lung cancer cases in women could be attributed to this effect of early age of first smoking.