- Urinary microbes and postoperative urinary tract infection risk in urogynecologic surgical patients. [Journal Article]
- IUInt Urogynecol J 2018; 29(12):1797-1805
- CONCLUSIONS: Postoperative UTI risk appears to be associated with preoperative bladder microbiome composition, where an abundance of L. iners appears to protect against postoperative UTI.
- Urinary symptoms are associated with certain urinary microbes in urogynecologic surgical patients. [Journal Article]
- IUInt Urogynecol J 2018; 29(12):1765-1771
- CONCLUSIONS: Two specific bacterial species detected in bladder urine, Atopobium vaginae and Finegoldia magna, are associated with preoperative urinary symptom severity in women undergoing POP/SUI surgery. The reservoir for Atopobium vaginae may be adjacent pelvic floor niches. This observation should be validated in a larger cohort to determine whether there is a microbiologic etiology for certain preoperative urinary symptoms.
- Color polymorphic lures target different visual channels in prey. [Journal Article]
- EEvolution 2016; 70(6):1398-408
- Selection for signal efficacy in variable environments may favor color polymorphism, but little is known about this possibility outside of sexual systems. Here we used the color polymorphic orb-web s…
Selection for signal efficacy in variable environments may favor color polymorphism, but little is known about this possibility outside of sexual systems. Here we used the color polymorphic orb-web spider Gasteracantha fornicata, whose yellow- or white-banded dorsal signal attracts dipteran prey, to test the hypothesis that morphs may be tuned to optimize either chromatic or achromatic conspicuousness in their visually noisy forest environments. We used data from extensive observations of naturally existing spiders and precise assessments of visual environments to model signal conspicuousness according to dipteran vision. Modeling supported a distinct bias in the chromatic (yellow morph) or achromatic (white morph) contrast presented by spiders at the times when they caught prey, as opposed to all other times at which they may be viewed. Hence, yellow spiders were most successful when their signal produced maximum color contrast against viewing backgrounds, whereas white spiders were most successful when they presented relatively greatest luminance contrast. Further modeling across a hypothetical range of lure variation confirmed that yellow versus white signals should, respectively, enhance chromatic versus achromatic conspicuousness to flies, in G. fornicata's visual environments. These findings suggest that color polymorphism may be adaptively maintained by selection for conspicuousness within different visual channels in receivers.
- Exercise Prevents Diet-Induced Cellular Senescence in Adipose Tissue. [Journal Article]
- DDiabetes 2016; 65(6):1606-15
- Considerable evidence implicates cellular senescence in the biology of aging and chronic disease. Diet and exercise are determinants of healthy aging; however, the extent to which they affect the beh…
Considerable evidence implicates cellular senescence in the biology of aging and chronic disease. Diet and exercise are determinants of healthy aging; however, the extent to which they affect the behavior and accretion of senescent cells within distinct tissues is not clear. Here we tested the hypothesis that exercise prevents premature senescent cell accumulation and systemic metabolic dysfunction induced by a fast-food diet (FFD). Using transgenic mice that express EGFP in response to activation of the senescence-associated p16(INK4a) promoter, we demonstrate that FFD consumption causes deleterious changes in body weight and composition as well as in measures of physical, cardiac, and metabolic health. The harmful effects of the FFD were associated with dramatic increases in several markers of senescence, including p16, EGFP, senescence-associated β-galactosidase, and the senescence-associated secretory phenotype (SASP) specifically in visceral adipose tissue. We show that exercise prevents the accumulation of senescent cells and the expression of the SASP while nullifying the damaging effects of the FFD on parameters of health. We also demonstrate that exercise initiated after long-term FFD feeding reduces senescent phenotype markers in visceral adipose tissue while attenuating physical impairments, suggesting that exercise may provide restorative benefit by mitigating accrued senescent burden. These findings highlight a novel mechanism by which exercise mediates its beneficial effects and reinforces the effect of modifiable lifestyle choices on health span.
- Incontinence medication response relates to the female urinary microbiota. [Journal Article]
- IUInt Urogynecol J 2016; 27(5):723-33
- CONCLUSIONS: Knowledge of an individual's urinary microbiome/microbiota may help refine UUI treatment. Complementary tools, DNA sequencing, and expanded urine culture provide information about bacteria that appear to be related to UUI incontinence status and treatment response in this population of adult women.
- Dysfunctional Striatal Systems in Treatment-Resistant Schizophrenia. [Journal Article]
- NNeuropsychopharmacology 2016; 41(5):1274-85
- The prevalence of treatment-resistant schizophrenia points to a discrete illness subtype, but to date its pathophysiologic characteristics are undetermined. Information transfer from ventral to dorsa…
The prevalence of treatment-resistant schizophrenia points to a discrete illness subtype, but to date its pathophysiologic characteristics are undetermined. Information transfer from ventral to dorsal striatum depends on both striato-cortico-striatal and striato-nigro-striatal subcircuits, yet although the functional integrity of the former appears to track improvement of positive symptoms of schizophrenia, the latter have received little experimental attention in relation to the illness. Here, in a sample of individuals with schizophrenia stratified by treatment resistance and matched controls, functional pathways involving four foci along the striatal axis were assessed to test the hypothesis that treatment-resistant and non-refractory patients would exhibit contrasting patterns of resting striatal connectivity. Compared with non-refractory patients, treatment-resistant individuals exhibited reduced connectivity between ventral striatum and substantia nigra. Furthermore, disturbance to corticostriatal connectivity was more pervasive in treatment-resistant individuals. The occurrence of a more distributed pattern of abnormality may contribute to the failure of medication to treat symptoms in these individuals. This work strongly supports the notion of pathophysiologic divergence between individuals with schizophrenia classified by treatment-resistance criteria.
- Signal design and courtship presentation coincide for highly biased delivery of an iridescent butterfly mating signal. [Journal Article]
- EEvolution 2015; 69(1):14-25
- Sensory drive theory contends that signaling systems should evolve to optimize transmission between senders and intended receivers, while minimizing visibility to eavesdroppers where possible. In vis…
Sensory drive theory contends that signaling systems should evolve to optimize transmission between senders and intended receivers, while minimizing visibility to eavesdroppers where possible. In visual communication systems, the high directionality afforded by iridescent coloration presents underappreciated avenues for mediating this trade-off. This hypothesis predicts functional links between signal design and presentation such that visual conspicuousness is maximized only under ecologically relevant settings and/or to select audiences. We addressed this prediction using Hypolimnas bolina, a butterfly in which males possess ultraviolet markings on their dorsal wing surfaces with a narrow angular reflectance function. Males bearing brighter dorsal markings are increasingly attractive to females, but also likely more conspicuous to predators. Our data indicate that, during courtship (and given the ritualized wingbeat dynamics at these times), males position themselves relative to females in such a way as to simultaneously maximize three components of known or putative signal conspicuousness: brightness, area, and iridescent flash. This suggests that male signal design and display have coevolved for the delivery of an optimally conspicuous signal to courted females. More broadly, these findings imply a potential signaling role for iridescence itself, and pose a novel example for how signal design may coevolve with the behavioral context of display.
- Visualizing a protein quake with time-resolved X-ray scattering at a free-electron laser. [Journal Article]
- NMNat Methods 2014; 11(9):923-6
- We describe a method to measure ultrafast protein structural changes using time-resolved wide-angle X-ray scattering at an X-ray free-electron laser. We demonstrated this approach using multiphoton e…
We describe a method to measure ultrafast protein structural changes using time-resolved wide-angle X-ray scattering at an X-ray free-electron laser. We demonstrated this approach using multiphoton excitation of the Blastochloris viridis photosynthetic reaction center, observing an ultrafast global conformational change that arises within picoseconds and precedes the propagation of heat through the protein. This provides direct structural evidence for a 'protein quake': the hypothesis that proteins rapidly dissipate energy through quake-like structural motions.
- Dysregulated but not decreased salience network activity in schizophrenia. [Journal Article]
- FHFront Hum Neurosci 2013; 7:65
- Effective estimation of the salience of environmental stimuli underlies adaptive behavior, while related aberrance is believed to undermine rational thought processes in schizophrenia. A network incl…
Effective estimation of the salience of environmental stimuli underlies adaptive behavior, while related aberrance is believed to undermine rational thought processes in schizophrenia. A network including bilateral frontoinsular cortex (FIC) and dorsal anterior cingulate cortex (dACC) has been observed to respond to salient stimuli using functional magnetic resonance imaging (fMRI). To test the hypothesis that activity in this salience network (SN) is less discriminately modulated by contextually-relevant stimuli in schizophrenia than in healthy individuals, fMRI data were collected in 20 individuals with schizophrenia and 13 matched controls during performance of a modified monetary incentive delay (MID) task. After quantitatively identifying spatial components representative of the FIC and dACC features of the SN, two principal analyses were conducted. In the first, modulation of SN activity by salience was assessed by measuring response to trial outcome. First-level general linear models were applied to individual-specific time-courses of SN activity identified using spatial independent component analysis (ICA). This analysis revealed a significant salience-by-performance-by-group interaction on the best-fit FIC component's activity at trial outcome, whereby healthy individuals but not individuals with schizophrenia exhibited greater distinction between the response to hits and misses in high salience trials than in low salience trials. The second analysis aimed to ascertain whether SN component amplitude differed between the study groups over the duration of the experiment. Independent-samples T-tests on back-projected, percent-signal-change scaled SN component images importantly showed that the groups did not differ in the overall amplitude of SN expression over the entire dataset. These findings of dysregulated but not decreased SN activity in schizophrenia provide physiological support for mechanistic conceptual frameworks of delusional thought formation.
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- The human Cx26-D50A and Cx26-A88V mutations causing keratitis-ichthyosis-deafness syndrome display increased hemichannel activity. [Journal Article]
- AJAm J Physiol Cell Physiol 2013 Jun 15; 304(12):C1150-8
- Mutations in the human gene encoding connexin 26 (Cx26 or GJB2) cause either nonsyndromic deafness or syndromic deafness associated with skin diseases. That distinct clinical disorders can be caused …
Mutations in the human gene encoding connexin 26 (Cx26 or GJB2) cause either nonsyndromic deafness or syndromic deafness associated with skin diseases. That distinct clinical disorders can be caused by different mutations within the same gene suggests that different channel activities influence the ear and skin. Here we use three different expression systems to examine the functional characteristics of two Cx26 mutations causing either mild (Cx26-D50A) or lethal (Cx26-A88V) keratitis-ichthyosis-deafness (KID) syndrome. In either cRNA-injected Xenopus oocytes, transfected HeLa cells, or transfected primary human keratinocytes, we show that both Cx26-D50A and Cx26-A88V form active hemichannels that significantly increase membrane current flow compared with wild-type Cx26. This increased membrane current accelerated cell death in low extracellular calcium solutions and was not due to increased mutant protein expression. Elevated mutant hemichannel currents could be blocked by increased extracellular calcium concentration. These results show that these two mutations exhibit a shared gain of functional activity and support the hypothesis that increased hemichannel activity is a common feature of human Cx26 mutations responsible for KID syndrome.