Development and utilization of dicamba-, glufosinate-, and 2,4-D-resistant crop cultivars will potentially have a significant influence on weed management in the southern United States. However, off-site movement to adjacent nontolerant crops and other plants is a concern in many areas of eastern North Carolina and other portions of the southeastern United States, especially where sensitive crops are grown. Cotton, peanut, and soybean are not resistant to these herbicides, will most likely be grown in proximity, and applicators will need to consider potential adverse effects on nonresistant crops when these herbicides are used. Research was conducted with rates of glufosinate, dicamba, and 2,4-D designed to simulate drift on cotton, peanut, and soybean to determine effects on yield and quality and to test correlations of visual estimates of percent injury with crop yield and a range of growth and quality parameters. Experiments were conducted in North Carolina near Lewiston-Woodville and Rocky Mount during 2009 and 2010. Cotton and peanut (Lewiston-Woodville and Rocky Mount) and soybean (two separate fields [Rocky Mount] during each year were treated with dicamba and the amine formulation of 2,4-D at 1/2, 1/8, 1/32, 1/128, and 1/512 the manufacturer's suggested use rate of 280 g ai ha−1and 540 g ai ha−1, respectively. Glufosinate was applied at rates equivalent to 1/2, 1/4, 1/8, 1/16, and 1/32 the manufacturer's suggested use rate of 604 g ai ha−1. A wide range of visible injury was noted at both 1 and 2 wk after treatment (WAT) for all crops. Crop yield was reduced for most crops when herbicides were applied at the highest rate. Although correlations of injury 1 and 2 WAT with yield were significant (P ≤ 0.05), coefficients ranged from −0.25 to −0.50, −0.36 to −0.62, and −0.40 to −0.67 for injury 1 WAT vs. yield for cotton, peanut, and soybean, respectively. These respective crops had ranges of correlations of −0.17 to −0.43, −0.34 to −0.64, and −0.41 to −0.60 for injury 2 WAT. Results from these experiments will be used to emphasize the need for diligence in application of these herbicides in proximity to crops that are susceptible as well as the need to clean sprayers completely before spraying sensitive crops.

The Gram-negative bacterium Burkholderia pseudomallei is the etiological agent of melioidosis and is remarkably resistant to most classes of antibacterials. Even after months of treatment with antibacterials that are relatively effective in vitro, there is a high rate of treatment failure, indicating that this pathogen alters its patterns of antibacterial susceptibility in response to cues encountered in the host. The pathology of melioidosis indicates that B. pseudomallei encounters host microenvironments that limit aerobic respiration, including the lack of oxygen found in abscesses and in the presence of nitric oxide produced by macrophages. We investigated whether B. pseudomallei could survive in a nonreplicating, oxygen-deprived state and determined if this physiological state was tolerant of conventional antibacterials. B. pseudomallei survived initial anaerobiosis, especially under moderately acidic conditions similar to those found in abscesses. Microarray expression profiling indicated a major shift in the physiological state of hypoxic B. pseudomallei, including induction of a variety of typical anaerobic-environment-responsive genes and genes that appear specific to anaerobic B. pseudomallei. Interestingly, anaerobic B. pseudomallei was unaffected by antibacterials typically used in therapy. However, it was exquisitely sensitive to drugs used against anaerobic pathogens. After several weeks of anaerobic culture, a significant loss of viability was observed. However, a stable subpopulation that maintained complete viability for at least 1 year was established. Thus, during the course of human infection, if a minor subpopulation of bacteria inhabited an oxygen-restricted environment, it might be indifferent to traditional therapy but susceptible to antibiotics frequently used to treat anaerobic infections.

Mycobacterium bovis BCG is widely used as a vaccine against tuberculosis (TB),Tuberculosis (TB) remains a major global health threat. Each year, about eight million new TB cases occur and two million people die from TB. It is estimated that one-third of the world population is latently infected with Mycobacterium tuberculosis. From this vast latent reservoir, about 10% of infected people are expected to develop overt TB disease during their lifetimes. However, with the expanding human immunodeficiency virus type 1-AIDS pandemic, this number is expected to soar in the next few decades (11, http://www.who.int /mediacentre/factsheets/fs104/en/).The current TB vaccine is the live attenuated bacterium Mycobacterium bovis Bacillus Calmette-Guérin (BCG). BCG is known to protect against severe forms of TB in young children and against leprosy. However, it does not efficiently and consistently protect against pulmonary TB in adults, the most prevalent and contagious form of TB; BCG also does not offer protection from reactivation of latent TB infection. This partly explains why BCG has little impact on the global TB epidemic despite its widespread use as a prophylactic TB vaccine (http: //www.who.int/wer/2004/en/wer7904.pdf). Over the years, many hypotheses have been put forward to explain the apparent variability in the protective efficacy of BCG, which varies from 0 to 80% (16). Explanations for this inconsistency include differences in trial methodology, host population genetics, use of different BCG vaccine strains (2), and heterogeneous immunity to a variety of environmental mycobacteria that may interfere with or mask the protection provided by BCG (7,26).Immune response profiles following BCG vaccination comprise myriad effector mechanisms, multiple T-cell subsets, and many targeted antigens. BCG is capable of inducing Th1 responses (38), which are critical in mycobacterial infections (17). In addition, BCG is also capable of inducing both CD4 ϩ and CD8ϩ T-cell responses to antigens shared with M. tuberculosis, such as secreted antigens of the mycolyl transferase family (Ag85) (19,20,33) and nondeleted members of the ESAT-6 family (e.g., TB10.4) (32), but also heat shock proteins like Hsp65 and Hsp70 (15). However, it is still not completely known how these and other antigen-specific immune responses contribute to protection against TB.Recently we studied human T-cell responses to DosR (Rv3133c) regulon-encoded antigens (referred to as TB latency antigens) of M. tuberculosis (24). We observed preferential recognition of latency antigens by Mantoux skin test-positive individuals with latent TB compared to patients with TB disease, suggesting that these immune responses are associated with latent TB disease (13,24). The DosR regulon is expressed by tubercle bacilli under in vitro conditions of hypoxia and

Inbred Wistar-Kyoto (WKY) rats have been proposed as a model of anxiety vulnerability as they display behavioral inhibition and a constellation of learning and reactivity abnormalities relative to outbred Sprague-Dawley (SD) rats. Together, the behaviors of the WKY rat suggest a hypervigilant state may contribute to its anxiety vulnerability. To test this hypothesis, open-field behavior, acoustic startle, pre-pulse inhibition and timing behavior were assessed in WKY and Sprague Dawley (SD) rats. Timing behavior was evaluated using a modified version of the peak-interval timing procedure. Training and testing of timing first occurred without audio-visual (AV) interference. Following this initial test, AV interference was included on some trials. Overall, WKY rats took much longer to leave the center of the arena, made fewer line crossings, and reared less, than did SD rats. WKY rats showed much greater startle responses to acoustic stimuli and significantly greater pre-pulse inhibition than did the SD rats. During timing conditions without AV interference, timing accuracy for both strains were similar; peak times for WKY and SD rats were not different. During interference conditions, however, the timing behavior of the two strains was very different. Whereas peak times for SD rats were similar between non-interference and interference conditions, peak times for WKY rats were shorter and response rates higher in interference conditions than in non-interference conditions. The enhanced acoustic startle response, greater prepulse inhibition and altered timing behavior with audio-visual interference supports a characterization of WKY strain as hypervigilant and provides further evidence for the use of the WKY strain as a model of anxiety vulnerability.

Increased yield potential associated with full‐season cotton (Gossypium hirsutum L.) varieties can be offset by excessive vegetative growth that leads to undesirable fruit shed and boll rot. Producers often make multiple mepiquat chloride (1,1‐dimethyl‐piperidinium chloride) applications with excessive seasonal use rates to combat this problem, often with inconsistent results. Field studies were conducted in 2004 and 2005 to evaluate reduced plant populations as a potential management tool to be used in conjunction with mepiquat chloride application strategies for managing plant height. Plant populations of 152883, 101929, and 50958 plants ha−1 received a single application at 12 nodes (15.2 g a.i. ha−1) or early bloom (45.8 g a.i. ha−1), sequential applications at 12 nodes (15.2 g a.i. ha−1) and early bloom (30.6 g a.i. ha−1), or the modified early bloom schedule (a plant growth regulator application decision aid that recommends rates and timing based on plant growth parameters). Mepiquat chloride application reduced final plant height at least 15 cm compared with the nontreated in both years but also reduced the number of main stem nodes in 2005. In 2005, lint yield was inversely related to plant population, and a significant yield response occurred with the modified early bloom mepiquat chloride application strategy. Mepiquat chloride application increased lint yield in 1 of 2 yr but was useful for reducing plant height regardless of population. Reducing plant population had no adverse effects on lint yield or fiber properties and may be valuable in achieving a desired plant stature with less intensive plant growth regulator management.

The hippocampus has been implicated in anxiety disorders and post-traumatic stress disorder (PTSD); human studies suggest that a dysfunctional hippocampus may be a vulnerability factor for the development of PTSD. In the current study, we examined the effect of hippocampal damage in avoidance learning, as avoidance is a core symptom of all anxiety disorders. First, the effect of hippocampal damage on avoidance learning was investigated in outbred Sprague Dawley (SD) rats. Second, the function of the hippocampus in Wistar-Kyoto (WKY) rats was compared to SD rats. The WKY rat is an animal model of behavioral inhibition, a risk factor for anxiety, and demonstrates abnormal avoidance learning, marked by facilitated avoidance acquisition and resistance to extinction. The results of the current study indicate that hippocampal damage in SD rats leads to impaired extinction of avoidance learning similar to WKY rats. Furthermore, WKY rats have reduced hippocampal volume and impaired hippocampal synaptic plasticity as compared to SD rats. These results suggest that hippocampal dysfunction enhances the development of persistent avoidance responding and, thus, may confer vulnerability to the development of anxiety disorders and PTSD.

The septohippocampal pathway contains cholinergic, GABAergic, and glutamatergic projections and has an established role in learning, memory, and hippocampal theta rhythm. Both GABAergic and cholinergic neurons in the medial septum-diagonal band of Broca (MSDB) have been associated with spatial memory, but the relationship between the two neuronal populations is not fully understood. The present study investigated the effect of selective GABAergic MSDB lesions on hippocampal acetylcholine (ACh) efflux and spatial memory during tasks that varied in memory demand. Male Sprague Dawley rats were given GABAergic lesions of the MSDB using GAT1-saporin (GAT1-SAP) and examined on spontaneous exploration (Experiment 1) and non-matching to position without (NMTP; Experiment 2) and with a delay (DNMTP; Experiment 3), while concurrently using in vivo microdialysis to measure hippocampal ACh efflux. Intraseptal GAT1-SAP treatment did not alter baseline or behaviorally stimulated hippocampal ACh efflux or maze exploration (Experiment 1). Moreover, GAT1-SAP did not alter evoked hippocampal ACh efflux related to NMTP nor did it impair working memory in NMTP (Experiment 2). In contrast, both ACh efflux and performance in DNMTP were impaired by intraseptal GAT1-SAP. Thus, GABAergic MSDB neurons are important for spatial working memory and modulate hippocampal ACh efflux under conditions of high memory load. The relationship between the septohippocampal cholinergic and GABAergic systems and working memory will be discussed.

Mycobacterium tuberculosis is the causative agent of tuberculosis, a disease that affects one-third of the world's population. The sole extant vaccine for tuberculosis is the live attenuated Mycobacterium bovis bacillus Calmette-Guerin (BCG). We examined 13 representative BCG strains from around the world to ascertain their ability to express DosR-regulated dormancy antigens. These are known to be recognized by T cells of M. tuberculosis-infected individuals, especially those harboring latent infections. Differences in the expression of these antigens could be valuable for use as diagnostic markers to distinguish BCG vaccination from latent tuberculosis. We determined that all BCG strains were defective for the induction of two dormancy genes: narK2 (Rv1737c) and narX (Rv1736c). NarK2 is known to be necessary for nitrate respiration during anaerobic dormancy. Analysis of the narK2/X promoter region revealed a base substitution mutation in all tested BCG strains and M. bovis in comparison to the M. tuberculosis sequence. We also show that nitrate reduction by BCG strains during dormancy was greatly reduced compared to M. tuberculosis and varied between tested strains. Several dormancy regulon transcriptional differences were also identified among the strains, as well as variation in their growth and survival. These findings demonstrate defects in DosR regulon expression during dormancy and phenotypic variation between commonly used BCG vaccine strains.