DNA methylation of Th2 lineage determination genes at birth is associated with allergic outcomes in childhood.

BACKGROUND: There is now increasing evidence that asthma and atopy originate in part in utero, with disease risk being associated with the altered epigenetic regulation of genes. OBJECTIVE AND METHODS: To determine the relationship between variations in DNA methylation at birth and the development of allergic disease, we examined the methylation status of CpG loci within the promoter regions of Th1/2 lineage commitment genes (GATA3, IL-4, IL-4R, STAT4 and TBET) in umbilical cord DNA at birth in a cohort of infants from the Southampton Women's Survey (n = 696) who were later assessed for asthma, atopic eczema and atopy. RESULTS: We found that higher methylation of GATA3 CpGs -2211/-2209 at birth was associated with a reduced risk of asthma at ages 3 (median ratio [median methylation in asthma group/median methylation in non-asthma group] = 0.74, P = .006) and 6-7 (median ratio 0.90, P = .048) years. Furthermore, we demonstrated that the GATA3 CpG loci associated with later risk of asthma lie within a NF-κB binding site and that methylation here blocks transcription factor binding to the GATA3 promoter in the human Jurkat T-cell line. Associations between umbilical cord methylation of CpG loci within IL-4R with atopic eczema at 12 months (median ratio 1.02, P = .028), and TBET with atopy (median ratio 0.98, P = .017) at 6-7 years of age were also observed. CONCLUSIONS AND CLINICAL RELEVANCE: Our findings provide further evidence of a developmental contribution to the risk of later allergic disorders and suggest that involvement of epigenetic mechanisms in childhood asthma is already demonstrable at birth.

Kommerell's diverticulum: A rare aortic arch anomaly.

Anomalies of the aortic arch associated with diverticulum are rare. We present a case of incidentally detected right-sided aortic arch with Kommerell's diverticulum and aberrant left subclavian artery.

Associations of Dual Task Exergaming with Cognitive-Motor Interference in Older Adults with Mild Cognitive Impairment: A Single-Arm Pilot Study.

Purpose: To examine the feasibility and effectiveness of dual task (DT) exergaming to improve volitional balance control in older adults with mild cognitive impairment (MCI). Methods: Ten older adults with MCI were examined at baseline (week-0) and post-training (week-5) on volitional balance control (maximum excursion of center of gravity, MXE [%]) while performing cognitive task (auditory clock test or letter number sequencing task) and on the NIH-motor and cognitive toolboxes. DT exergaming training lasted for 12 sessions which consisted of performing explicit cognitive tasks while playing the Wii-Fit balance games. Results: From pre- to post-training, MXE improved (p<0.05); however, cognitive accuracy (cognitive task) remained the same (p>0.05). Improvement in NIH motor and cognitive toolbox tests was observed post-training (p<0.05). Conclusion: DT exergaming was associated to improvements in balance control under attention-demanding conditions in MCI. Future studies may focus on examining the efficacy of such training.

Safety and activity of vandetanib in combination with everolimus in patients with advanced solid tumors: a phase I study.

BACKGROUND: Preclinical studies suggest that combining vandetanib (VAN), a multi-tyrosine kinase inhibitor of rearranged during transfection (RET) proto-oncogene, vascular endothelial growth factor receptor (VEGFR), and epidermal growth factor receptor (EGFR), with everolimus (EV), a mammalian target of rapamycin (mTOR) inhibitor, may improve antitumor activity. We determined the safety, maximum tolerated dose (MTD), recommended phase II dose (RP2D), and dose-limiting toxicities (DLTs) of VAN + EV in patients with advanced solid cancers and the effect of combination therapy on cancer cell proliferation and intracellular pathways. PATIENTS AND METHODS: Patients with refractory solid tumors were enrolled in a phase I dose-escalation trial testing VAN (100-300 mg orally daily) + EV (2.5-10 mg orally daily). Objective responses were evaluated using RECIST v1.1. RET mutant cancer cell lines were used in cell-based studies. RESULTS: Among 80 patients enrolled, 72 (90%) patients were evaluable: 7 achieved partial response (PR) (10%) and 37 had stable disease (SD) (51%; duration range: 1-27 cycles). Clinical benefit (SD or PR ≥ 6 months) was observed in 26 evaluable patients [36%, 95% confidence intervals (CI) (25% to 49%)]. In 80 patients, median overall survival (OS) was 10.5 months [95% CI (8.5-16.1)] and median progression-free survival (PFS) 4.1 months [95% CI (3.4-7.3)]. Six patients (7.5%) experienced DLTs and 20 (25%) required dose modifications. VAN + EV was safe, with fatigue, rash, diarrhea, and mucositis being the most common toxicities. In cell-based studies, combination therapy was superior to monotherapy at inhibiting cancer cell proliferation and intracellular signaling. CONCLUSIONS: The MTDs and RP2Ds of VAN + EV are 300 mg and 10 mg, respectively. VAN + EV combination is safe and active in refractory solid tumors. Further investigation is warranted in RET pathway aberrant tumors.

Immediate and latent interlimb transfer of gait stability adaptation following repeated exposure to slips.

The authors trained 21 participants by using blocked-and-mixed exposure to right-side slips and then caused them to slip unexpectedly on the untrained left side. Authors retested participants with a right slip and a left slip at 1 week, 2 weeks, 1 month, and 4 months. The authors found that preslip stability on the first untrained left slip improved and was significantly greater than that on the first right slip, which probably contributed to the reduction in incidence of falls from approximately 30% to approximately 10%. Postslip stability and base of support (BOS) slip velocity were similar to those on the first right slip and much lower than those on the last right slip. Increases in pre- and postslip stabilities and BOS slip velocity during the left slip led to reductions in backward balance loss (BLOB) from approximately 95% on initial left slip to approximately 60% and to approximately 25% on the 1st and 3rd retest sessions, respectively. In contrast, BLOB remained at a constant approximately 40% level on the right slip of the same retest sessions. The results indicate a partial immediate transfer and a possible latent transfer.

Acquired CDK6 amplification promotes breast cancer resistance to CDK4/6 inhibitors and loss of ER signaling and dependence.

Dysregulated activation of the CDK4/6 kinases is a hallmark of most mammary-derived carcinomas. ATP-competitive inhibitors against this complex have been recently advanced in the clinic and have shown significant activity, particularly against tumors driven by the estrogen receptor (ER). However, resistance to these compounds has begun to emerge often months to years after their initiation. We investigated potential mechanisms of resistance using cell line models that are highly sensitive to this class of drugs. After prolonged exposure to the selective and potent CDK4/6 inhibitor LY2835219, clones emerged and several were found to harbor amplification of the CDK6 kinase. Amplification of CDK6 resulted in a marked increase in CDK6 expression and reduced response of the CDK4/6 target, phospho-Rb (pRb), to CDK4/6 inhibitors. Knockdown of CDK6 restored drug sensitivity, while enforced overexpression of CDK6 was sufficient to mediate drug resistance. Not only did CDK6 overexpression mediate resistance to CDK4/6 inhibitors but it also led to reduced expression of the ER and progesterone receptor (PR), and diminished responsiveness to ER antagonism. The reduced ER/PR expression after CDK4/6 inhibitor resistance was additionally observed in tumor biopsy specimens from patients treated with these drugs. Alternative mechanisms of resistance to CDK4/6 inhibitors such as loss of pRb and cyclin E1 overexpression also exhibited decreased hormone responsiveness, suggesting that the clinical paradigm of sequential endocrine-based therapy may be ineffective in some settings of acquired CDK4/6 resistance.

Mutagenesis in Chinese hamster cells by cyclopenta(a)phenanthrenes activated by a human hepatoma cell line.

The cyclopenta(a)phenanthrene, 15,16-dihydro-11-methyl-cyclopenta(a)phenanthren-17-one, had potent mutagenic activity in cell-mediated mutation assays with V79 Chinese hamster cells as targets, and cells of the human hepatoma line HepG2 as mediators of activation. The compound was inactive when low-passage hamster embryo cells were used as activators. When the mutagenic activity of a series of cyclopenta(a)phenanthrenes was compared in mutation assays with HepG2 cells as activators, there was a good correlation between mutagenic activity in this system and carcinogenic activity in mouse skin in vivo. One exception was a noncarcinogenic compound, which is mutagenic in the Ames' test, and was also mutagenic in the mammalian cell assay.

The relationship between metabolism, DNA binding, and carcinogenicity of 15,16-dihydro-11-methylcyclopenta(alpha)phenanthren-17-one in the presence of a microsomal enzyme inhibitor.

The mean latent period for skin tumor production by the carcinogen 15, 16-dihydro-11-methylcyclopenta [alpha] phenanthren-17-one (Compound IVb) in the mouse was 30 weeks for a dose of 60 mug/week and about 45 weeks for 60 mug/week, while at 0.6 mug/week, no tumors were observed during 100 weeks. Simultaneous administration of the closely related noncarcinogen (IVa) (54 mug/week) together with the carcinogen at 60 mug/week had no effect on the mean latent period. Simultaneous administration of a threefold quantity of the microsomal enzyme inhibitor 7, 8-benzoflavone (I) with the carcinogen at the highest dose increased the mean latent period to 38 weeks, while at the intermediate dose it completely suppressed tumor formation. Neither ketone IVa nor IVb bound covalently to calf thymus DNA in vitro without prior metabolic activation. After incubation with rat liver microsomes and NADPH in the presence of air, both ketones bound covalently to added DNA in vitro, the noncarcinogen (IVa) about four times more extensively than the carcinogen (IVb), roughly in proportion to the overall extents to which these ketones were metabolized. In contrast, overall metabolism of the carcinogen (IVb) was somewhat increased by the addition of a threefold quantity of the inhibitor (I) to the incubation mixture, but binding to added DNA was almost completely prevented. These results are discussed in connection with the hypothesis that cellular DNA is the target of the carcinogen (IVb) for tumor initiation.

Mutagenic and carcinogenic metabolites of the carcinogen 15,16-dihydro-11-methylcyclopenta[a]phenanthren-17-one.

Microsomal metabolites of the carcinogen 15,16-dihydro-11-methylcyclopenta[a]phenanthren-17-one (Structure I) were separated by high-pressure liquid chromatography, and their structures were established on the basis of their ultraviolet and mass spectra, together with considerations of their general chemical properties. This was assisted by comparisons with metabolites formed in the same way from the synthetic 15-hydroxy (Structure III), 16-hydroxy (Structure II), and 11-hydroxymethyl (Structure IV) derivatives, which themselves occur as metabolites of Structural I. Products derived from attack at the two benzo-ring double bonds occurred, but no K-region products were found. Only metabolites having a non-bay region 3,4-dihydrodiol system were mutagenic and bound to DNA after in vitro microsomal activation, and it was concluded that the 3,4-dihydro-3,4-diol (Metabolite e) was the main form and that the 3,4-diols of the monools (Structure II to IV) were minor proximate forms of this carcinogen. In a two-stage experiment, the synthetic 16-ol (Structure II) was shown to be almost as carcinogenic as was Structure I itself in mice; the 15-ol (Structure III) and 11-hydroxymethyl derivative (Structure IV) were much less active. The same order was also observed in the mutagenicity of these compounds in the Ames test.

Bay region distortions in cyclopenta[a]phenanthrenes.

Two newly synthesized cyclopenta[a]phenanthrenes, namely the 1-methyl (VIII) and 7,11-dimethyl (VII) derivatives of the parent ketone 15,16-dihydrocyclopenta[a]phenanthren-17-one (I), have been tested for their capacity to produce skin tumors in mice. The former (VIII) is essentially inactive, whereas the latter (VII) is very potent in both repeated application and two-stage tests. X-ray crystallographic structure analyses have been carried out on seven derivatives of (I), namely its 11-methyl (II), 11,12-dimethyl (III), 11-methoxy (V), 11-ethyl (VI) and 7,11-dimethyl (VII) analogues (carcinogens), the 1-methyl derivative (VIII), and 11,12,15,16-tetrahydro-11-methyl-17-oxocyclopenta[a]phenanthrene (IV) (both non-carcinogens). The detailed molecular structures resulting from these studies have shown the effects of steric interactions and substitutions on the bay-region geometry. The methyl group on C(11) causes distortions of the molecule in the bay region. Out-of-plane distortions in the bay regions of the 11-methyl derivatives (II, III, VII) are greater than for the 11-methoxy or the 11-ethyl derivatives (V, VI). Molecules (except for III and IV) are packed in the crystals with interactions that include C = O...H interactions; this packing is in layers that are nearly parallel to each other. A hydrogen atom of the 11-methyl group appears, from computer modeling, to interact sterically with the hydrogen atom of the bay-region expoxide group in the activated diol-epoxide; this steric interaction may force one conformer of the diol-epoxide to be the predominant form, thereby accounting for the importance of a bay-region methyl group. Further computer modeling has been used to analyze possible modes of interaction of the diol-epoxides of cyclopenta[a]phenanthrenes with DNA.

Influence of gait speed on stability: recovery from anterior slips and compensatory stepping.

Falls precipitated by slipping are a major health concern, with the majority of all slip-related falls occurring during gait. Recent evidence shows that a faster and/or more anteriorly positioned center of mass (COM) is more stable against backward balance loss, and that compensatory stepping is the key to recovering stability upon balance loss. The purposes of this paper were to determine whether walking speed affected gait stability for backward balance loss at slip onset and touchdown of compensatory stepping, and whether compensatory stepping response resembled the regular gait pattern. Forty-seven young subjects were slipped unexpectedly either at a self-selected fast, natural or slow speed. Speed-related differences in stability at slip onset and touchdown of the subsequent compensatory step were analyzed using the COM position-velocity state. The results indicate that gait speed highly correlated with stability against backward balance loss at slip onset. The low COM velocity of the slow group was not sufficiently compensated for by a more anteriorly positioned COM associated with a shorter step length at slip onset. At touchdown of the compensatory step, the speed-related differences in stability diminished, due to the continued advantage of anterior COM positioning from a short compensatory step retained by the slow group, coupled with an increase in COM velocity. Compensatory step length and relative COM position altered as a function of gait speed, indicating the motor program for gait regulation may play a role in modulating the compensatory step.

Expression of the Manduca sexta allatotropin gene in cells of the central and enteric nervous systems.

Manduca sexta allatotropin (Mas-AT) was isolated and first characterized as a peptide that stimulated juvenile hormone biosynthesis in adult lepidopteran corpora allata and was subsequently shown to have cardioacceleratory activity in the pharate adult. In this study, we identified the cells in the nervous system of the insect that contain mRNA encoding Mas-AT and immunoreactivity against a polyclonal antiserum to Mas-AT. In larvae, Mas-AT mRNA and immunoreactivity was most abundant in two cells in the frontal ganglion, which project their axons down the recurrent nerve toward the gut, and in cells in the terminal abdominal ganglion. Lower levels of Mas-AT mRNA were detected in the brain and subesophageal ganglion. In the pupal and pharate adult stages, we detected Mas-AT mRNA and immunoreactivity in cells of the abdominal ganglia and in additional cells in the terminal abdominal ganglion. These additional cells in the ventral nerve cord that express Mas-AT during the pupal and pharate adult stages include cells that differentiate during metamorphosis as well as cells that exist in larvae but do not begin to express Mas-AT until these later developmental stages. Some of the cells that exhibit Mas-AT immunoreactivity lack Mas-AT mRNA, suggesting that the antisera used in this and previous studies recognizes other peptides in addition to Mas-AT. This pattern of expression suggests that Mas-AT may mediate multiple physiological functions during the life cycle of the insect, including the larval stage in which no function has yet been described for the peptide.

Growth characteristics of the chimeric Japanese encephalitis virus vaccine candidate, ChimeriVax-JE (YF/JE SA14--14--2), in Culex tritaeniorhynchus, Aedes albopictus, and Aedes aegypti mosquitoes.

The Japanese encephalitis (JE) virus vaccine candidate, ChimeriVax-JE, which consists of a yellow fever (YF) 17D virus backbone containing the prM and E genes from the JE vaccine strain JE SA14--14--2, exhibits restricted replication in non-human primates, producing only a low-level viremia following peripheral inoculation. Although this reduces the likelihood that hematophagous insects could become infected by feeding on a vaccinated host, it is prudent to investigate the replication kinetics of the vaccine virus in mosquito species that are known to vector the viruses from which the chimera is derived. In this study ChimeriVax-JE virus was compared to its parent viruses, as well as to wild-type JE virus, for its ability to replicate in Culex tritaeniorhynchus, Aedes albopictus, and Aedes aegypti mosquitoes. Individual mosquitoes were exposed to the viruses by oral ingestion of a virus-laden blood meal or by intrathoracic (IT) virus inoculation. ChimeriVax-JE virus did not replicate following ingestion by any of the three mosquito species. Additionally, replication was not detected after IT inoculation of ChimeriVax-JE in the primary JE virus vector, Cx. tritaeniorhynchus. ChimeriVax-JE exhibited moderate growth following IT inoculation into Ae. aegypti and Ae. albopictus, reaching titers of 3.6-5.0 log(10) PFU/mosquito. There was no change in the virus genotype associated with replication in mosquitoes. Similar results were observed in mosquitoes of all three species that were IT inoculated or had orally ingested the YF 17D vaccine virus. In contrast, all mosquitoes either IT inoculated with or orally fed wild-type and vaccine JE viruses became infected, reaching maximum titers of 5.4-7.3 log(10) PFU/mosquito. These results indicate that ChimeriVax-JE virus is restricted in its ability to infect and replicate in these mosquito vectors. The low viremia caused by ChimeriVax-JE in primates and poor infectivity for mosquitoes are safeguards against secondary spread of the vaccine virus.

Effect of type of cognitive task and walking speed on cognitive-motor interference during dual-task walking.

OBJECTIVE: We aimed to determine the effect of distinctly different cognitive tasks and walking speed on cognitive-motor interference of dual-task walking. METHODS: Fifteen healthy adults performed four cognitive tasks: visuomotor reaction time (VMRT) task, word list generation (WLG) task, serial subtraction (SS) task, and the Stroop (STR) task while sitting and during walking at preferred-speed (dual-task normal walking) and slow-speed (dual-task slow-speed walking). Gait speed was recorded to determine effect on walking. Motor and cognitive costs were measured. RESULTS: Dual-task walking had a significant effect on motor and cognitive parameters. At preferred-speed, the motor cost was lowest for the VMRT task and highest for the STR task. In contrast, the cognitive cost was highest for the VMRT task and lowest for the STR task. Dual-task slow walking resulted in increased motor cost and decreased cognitive cost only for the STR task. CONCLUSIONS: Results show that the motor and cognitive cost of dual-task walking depends heavily on the type and perceived complexity of the cognitive task being performed. Cognitive cost for the STR task was low irrespective of walking speed, suggesting that at preferred-speed individuals prioritize complex cognitive tasks requiring higher attentional and processing resources over walking. While performing VMRT task, individuals preferred to prioritize more complex walking task over VMRT task resulting in lesser motor cost and increased cognitive cost for VMRT task. Furthermore, slow walking can assist in diverting greater attention towards complex cognitive tasks, improving its performance while walking.

Adaptation and generalization to opposing perturbations in walking.

Little is known on how the CNS would select its movement options when a person faces a novel or recurring perturbation of two opposing types (slip or trip) while walking. The purposes of this study were (1) to determine whether young adults' adaptation to repeated slips would interfere with their recovery from a novel trip, and (2) to investigate the generalized strategies after they were exposed to a mixed training with both types of perturbation. Thirty-two young adults were assigned to either the training group, which first underwent repeated-slip training before encountering a novel, unannounced trip while walking, or to the control group, which only experienced the same novel, unannounced trip. The former group would then experience a mix of repeated trips and slips. The results indicated that prior adaptation to slips had only limited interference during the initial phase of trip recovery. In fact, the prior repeated-slip exposure had primed their reaction, which mitigated any error resulting from early interference. As a result, they did not have to take a longer compensatory step for trip recovery than did the controls. After the mixed training, subjects were able to converge effectively the motion state of their center of mass (in its position and velocity space) to a stable and generalized "middle ground" steady-state. Such movement strategies not only further strengthened their robust reactive control of stability, but also reduced the CNS' overall reliance on accurate context prediction and on feedback correction of perturbation-induced movement error.

Generalization of motor adaptation to repeated-slip perturbation across tasks.

Similar adaptations improve both proactive and reactive control of center-of-mass (COM) stability and limb support against gravity during different daily tasks (e.g., sit-to-stand and walking) as a consequence of perturbation training for resisting falls. Yet it is unclear whether--or to what extent--such similarities actually promote inter-task generalization. The purpose of this study was therefore to determine whether young adults could indeed transfer their adaptive control, acquired from sit-to-stand-slip, to improve their likelihood of a recovery from an unannounced novel slip in walking. Subjects underwent either repeated slips during sit-to-stand before experiencing an unannounced, novel slip during walking (training group, n=20), or they received no prior training before the same gait-slip (control group, n=23). The subjects demonstrated training-induced generalization of their improved proactive control of stability in post-training (unperturbed) gait pattern that was more stable against backward balance loss than was that of their own pre-training pattern as well the gait pattern of the subjects in the control group. Upon the unannounced novel gait-slip, the training group showed significantly lower incidence of both falls and balance loss than that shown by the control, resulting from the improvements in the reactive control of limb support and slip velocity, which directly influenced the control of their COM stability. Such transfer could occur when the subjects' central nervous system recalibrates the non-task-specific, generalized representation of stability limits during the initial training to guide both their feed-forward adjustments and their feedback responses. The findings of the inter-task generalization suggests that behavioral changes induced via the perturbation training paradigm have the potential to prevent falls across the spectrum of cyclic and non-cyclic activities.

Independent influence of gait speed and step length on stability and fall risk.

With aging, individuals' gaits become slower and their steps shorter; both are thought to improve stability against balance threats. Recent studies have shown that shorter step lengths, which bring the center of mass (COM) closer to the leading foot, improve stability against slip-related falls. However, a slower gait, hence lower COM velocity, does the opposite. Due to the inherent coupling of step length and speed in spontaneous gait, the extent to which the benefit of shorter steps can offset the slower speed is unknown. The purpose of this study was to investigate, through decoupling, the independent effects of gait speed and step length on gait stability and the likelihood of slip-induced falls. Fifty-seven young adults walked at one of three target gait patterns, two of equal speed and two of equal step length; at a later trial, they encountered an unannounced slip. The results supported our hypotheses that faster gait as well as shorter steps each ameliorates fall risk when a slip is encountered. This appeared to be attributable to the maintenance of stability from slip initiation to liftoff of the recovery foot during the slip. Successful decoupling of gait speed from step length reveals for the first time that, although slow gait in itself leads to instability and falls (a one-standard-deviation decrease in gait speed increases the odds of fall by 4-fold), this effect is offset by the related decrease in step length (the same one-standard-deviation decrease in step length lowers fall risk by 6 times).