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1.
Immunity ; 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31471107

##### RESUMO

Although recent progress provides mechanistic insights into the pathogenesis of pulmonary fibrosis (PF), rare anti-PF therapeutics show definitive promise for treating this disease. Repeated lung epithelial injury results in injury-repairing response and inflammation, which drive the development of PF. Here, we report that chronic lung injury inactivated the ubiquitin-editing enzyme A20, causing progressive accumulation of the transcription factor C/EBPß in alveolar macrophages (AMs) from PF patients and mice, which upregulated a number of immunosuppressive and profibrotic factors promoting PF development. In response to chronic lung injury, elevated glycogen synthase kinase-3ß (GSK-3ß) interacted with and phosphorylated A20 to suppress C/EBPß degradation. Ectopic expression of A20 or pharmacological restoration of A20 activity by disturbing the A20-GSK-3ß interaction accelerated C/EBPß degradation and showed potent therapeutic efficacy against experimental PF. Our study indicates that a regulatory mechanism of the GSK-3ß-A20-C/EBPß axis in AMs may be a potential target for treating PF and fibroproliferative lung diseases.

2.
Phys Chem Chem Phys ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31478043

##### RESUMO

The polyamide (PA) layer on the surface of thin-film-composite reverse osmosis membranes is the core aspect of membrane-based desalination technology. In recent years, molecular dynamics simulations have been increasingly used to disclose the physicochemical properties of the PA layer. However, the currently reported all-atom PA layer models do not exhibit gradient variation of the structural properties of the layer, and they can only represent the innermost region of the PA layer. With the help of our recently developed universal toolkit "MembrFactory", this paper reports a modeling method that can be used to construct a gradient crosslinking model and surface grafting model for the PA layer. A fully atomistic model of the PA layer was constructed, in which the degree of crosslinking (DC) was changed gradiently along the thickness direction. The structure of the PA layer model and the transport dynamics of the water molecules within it were systematically investigated using equilibrium molecular dynamics simulations. We found that the DC is the lowest and the water molecules have the strongest self-diffusion ability in the interfacial region of the PA layer model. Meanwhile, the pore size is distributed widely in the region. Subsequently, we modified the surface of the PA layer model with PEG coatings, and their coverage ratio was around 75%. The radial distribution function analysis showed that water molecules prefer to coordinate with the oxygen atoms in PEG. Furthermore, two contaminant molecules, 1-ethyl-2-methyl benzene and n-decane, were selected to investigate the antifouling properties of the PEG-modified PA layer. By analysing the trajectories of the pollutants and calculating the potential of the mean force, we found that the antifouling performance of a PEG-modified PA layer is not only related to the hydrophobicity and the size of the pollutant, but is also related to the coverage ratio of the PEG layer.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31480140

##### RESUMO

Objective: To develop healthier comminuted meat products to meet consumer demand, the gel properties, rheological properties, microstructure and water distribution of pork meat batters formulated with various amounts of bamboo shoot dietary fiber (BSDF) were investigated. Methods: Different levels of BSDF (0-4%) were added to pork batters, and the pH, color, water-holding capacity, texture and rheological properties of pork batters were determined. Then, pork batters were analyzed for their microstructure and water distribution using scanning electron microscopy (SEM) and low-field nuclear magnetic resonance (LF-NMR). Results: Compared with the control, BSDF addition into meat batters showed a significant reduction in L*-value and a significant increase in b*-value (Pï¼0.05). BSDF addition of up to 4% reduced the pH value of pork batters by approximately 0.15 units; however, the cooking loss and expressible water loss decreased significantly (P<0.05) with the increased addition of BSDF. The hardness and gel strength were noticeably enhanced (Pï¼0.05) as the content of BSDF increased. The rheological results showed that BSDF added into pork batters produced higher storage modulus (G') and loss modulus (G'') values. The SEM images suggested that the addition of BSDF could promote pork batters to form a more uniform and compact microstructure. The proportion of immobilized water increased significantly (P<0.05), while the population of free water was decreased (P<0.05), indicating that BSDF improved the water-holding capability of pork batters by decreasing the fraction of free water. Conclusion: BSDF could improve the gel properties, rheological properties and water distribution of pork meat batters and decrease the proportion of free water, suggesting that BSDF has great potential as an effective binder in comminuted meat products.

4.
Elife ; 82019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31482844

##### RESUMO

TMEM16B (ANO2) is the Ca2+-activated chloride channel expressed in multiple brain regions, including the amygdala. Here we report that Ano2 knockout mice exhibit impaired anxiety-related behaviors and context-independent fear memory, thus implicating TMEM16B in anxiety modulation. We found that TMEM16B is expressed in somatostatin-positive (SOM+) GABAergic neurons of the central lateral amygdala (CeL), and its activity modulates action potential duration and inhibitory postsynaptic current (IPSC). We further provide evidence for TMEM16B actions not only in the soma but also in the presynaptic nerve terminals of GABAergic neurons. Our study reveals an intriguing role for TMEM16B in context-independent but not context-dependent fear memory, and supports the notion that dysfunction of the amygdala contributes to anxiety-related behaviors.

5.
J Phys Chem B ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31498630

##### RESUMO

Multigeometry nanoparticles (MGNs) have a high level of complexity both in composition and structure, and they are prevailing in nature and have shown great potential for multifunctional nanomaterials and hierarchy self-assembly. Polymer self-assembly is a common way to construct MGNs. However, up to now, the self-assembly strategy and the polymer category to fabricate MGNs are quite limited, and it is still a big challenge to get MGNs in a controlled way. Herein, by employing dissipative particle dynamics simulation, we provide a new "covalent bonding-forced orthogonal self-assembly" strategy for the preparation of MGNs through the self-assembly of block alternating copolymers. Without any additional cautious control, block alternating copolymers can directly self-assemble into various MGNs, except for two basic requirements: the critical molecular weight of each block and the incompatibility of different blocks. Any different simple geometries, like vesicles, cylinders and spheres, can be combined at will to construct arbitrary customized MGNs by changing the blocks. We further explore the effect of polymer concentration and the volume ratio of different blocks, through which the sizes, components and structures of the MGNs can be regulated simply. Besides, we extend this strategy to ternary systems to fabricate much more complicated nanoparticles with triple geometries. We believe the present work has provided a promising and simple strategy to efficiently construct MGNs with precisely controllable geometries.

6.
Med Phys ; 2019 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-31495935

##### RESUMO

7.
Med Phys ; 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31487396

##### RESUMO

8.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(9): 919-923, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31506154

##### RESUMO

A girl, aged 15 months, attended the hospital due to recurrent skin erythema, blisters, and desquamation for more than 7 months. Giemsa staining and immunohistochemical staining showed mast cell infiltration and degranulation. Hematoxylin staining showed spinous layer edema and blister formation under the epidermis, with a large amount of serous fluid and a small number of inflammatory cells in the blister. Marked edema was observed in the dermis, with diffused mononuclear cell infiltration. The girl was diagnosed with mastocytosis. Mastocytosis should be considered for children with recurrent skin erythema and blisters.

9.
J Ethnopharmacol ; 246: 112219, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31494201

##### RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Xiaoyaosan (XYS), a famous and classic traditional Chinese prescription, has been used for long time in treating depressive disorders. XYS consists of Radix Bupleuri (Bupleurum chinense DC.), Radix Angelicae Sinensis (Angelica sinensis (Oliv.) Diels), Radix PaeoniaeAlba (Paeonia lactiflora Pall.), Rhizoma Atractylodis Macrocepha lae (Atractylodes macrocephala Koidz.), Poria (Poria cocos (Schw.)Wolf), Radix Glycyrrhizae (Glycyrrhiza uralensis Fisch.), Herba Menthae Haplocalycis (Mentha haplocalyx Briq.), and Rhizoma Zin-giberis Recens (Zingiber officinale Rosc.). AIM OF THE STUDY: A GC-MS based metabolomics approach was applied to discover the potential biomarkers that were related to metabolic differences between healthy volunteers and depression cohort diagnosed by HAMD and CGI, and to demonstrate the potential utility of these biomarkers in the diagnosis of depression and pharmaceutical efficacy of XYS. MATERIALS AND METHODS: A total of 17 depressed patients and the 17 age- and gender-matched healthy subjects were served as the primary cohort. The depressed patients were screened according to the Chinese Classification of Mental Disorder (CCMD-3) and the Hamilton Depression Scale (HAMD). In addition, five other depressed patients were also enrolled as the primary cohort when the final step of sample collection was conducted. Plasma samples were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). Clinical and metabolomics data were analyzed by multivariate statistics analysis, Receiver Operating Characteristic (ROC) curve and MetaboAnalyst. RESULTS: We observed significant differences between depression cohort and healthy volunteers, and between patients before and after the treatment of XYS. The method was then clinically validated in an independent validation cohort. Levels of oxalic and stearic acids significantly increased in depressed patients' plasma while valine and urea significantly decreased, as compared with healthy controls. Of note, XYS reversed these metabolite changes in terms of regulating dysfunctions in glyoxylate and dicarboxylate metabolism, fatty acid biosynthesis, valine, leucine and isoleucine biosynthesis, and arginine and proline metabolism. Importantly, the combination of oxalic and stearic acids is in prospect as diagnose biomarkers. CONCLUSIONS: This study highlights the clinical application of metabolomics in disease diagnose and therapy evaluation, which will help in improving our understanding of depression and will lay solid foundation for the clinic application of TCMs. In addition, it suggests that the combination of the two potential biomarkers had also achieved a high diagnostic value, which consequently could be used a diagnose biomarkers.

10.
Mater Sci Eng C Mater Biol Appl ; 104: 109745, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499963

##### RESUMO

Chronic wounds are of high incidence, difficult to heal, and can cause serious consequences if not properly treated. Doxycycline (DCH) is a broad-spectrum antibiotic and matrix metalloproteinases inhibitor, which has prominent efficacy for chronic wound treatment. Topical DCH treatment is the common administration route for chronic wounds in clinic but may result in low therapeutic efficacy and cause skin irritation at high DCH concentration, since it is difficult to control local drug concentration in the wounds and maintain the effective DCH concentration for a long time. In this study, we prepared DCH-encapsulated polylactide (DCH/PLA) nanofibers by a simple electrospinning method. Imaging studies showed that smooth and continuous DCH/PLA nanofibers with homogeneous DCH distribution were obtained at varied DCH loading content in the range of 5-30%. Mechanical property, water vapour permeability and absorbency of these nanofibers could meet the requirement as wound dressings. By adjusting DCH loading content, the wettability of the nanofibers could be transferred from hydrophobic to hydrophilic, and the release rate of DCH could be controlled in a sustained manner from three days to two weeks. Results of cytotoxicity and antibacterial test indicated that DCH/PLA nanofibers showed good cytocompatibility to L929 mouse fibroblast cells and exhibited positive antibacterial activity against Escherichia coli, suggesting its ability to treat/prevent infectious wounds. For full-thickness wound treatment of diabetic rats, DCH/PLA nanofiber mats can speed up wound healing to a higher extent than topical DCH treatment, due to the sustained release of DCH with less side effects. Our results indicate that DCH/PLA nanofiber mats hold great potential as wound dressings for chronic wound treatment.

11.
Appl Opt ; 58(18): 4835-4845, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31503798

##### RESUMO

The imaging quality of an airborne infrared (IR) system is limited by the angular disturbance of the airborne platform. Based on the full-chain (IR scene-atmosphere-optical system-detector-airborne platform) signal transmission process, this study focused on the low-frequency sinusoidal angular disturbance features of the airborne platform and accurately calculated the point spread function caused by the angular disturbance and the IR imaging features when the IR system's different locations were dynamically simulated in a three-dimensional scene. First, the degradation mechanism of the IR imaging features resulting from the angular disturbance was analyzed from the viewpoint of scene radiation signal transmission and detector sampling. Then, the dynamic simulation in the three-dimensional scene resulting from the angular disturbance was realized by considering the geometric transformation of the spatial imaging, scale registration of the spatial sampling, radiation coupling, and angular disturbance caused by the airborne platform. Finally, the distances detected under different disturbance conditions were predicted using the established model. The obtained results provide data supporting the demonstration, verification, and optimization of the IR imaging system's design scheme.

12.
J Opt Soc Am A Opt Image Sci Vis ; 36(9): 1585-1590, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31503855

##### RESUMO

The conventional concave diffraction grating (CDG) is commonly operated as a coarse demultiplexer device due to significant increases in the chip size and cost for large dispersion. Compact dense wavelength multiplexing is proposed and demonstrated by utilizing a dual-input CDG integrated with dielectric multidirectional reflectors. This structure allows light beams incident from two different directions to be efficiently reflected and get diffracted into the respective output waveguides by a single grating, thus creating a doubled channel number and halved channel spacing while keeping the chip size constant. The dielectric multidirectional reflector is designed by one-dimensional photonic crystal theory and used as the grating tooth to provide high reflectivities over a wide angular range. Simulation results suggest that the dual-input CDG with incident angles of 1° and 6° exhibits efficiency of more than $-0.564 \,\,{\rm{dB}}$ and crosstalk less than $-21.2 \,\,{\rm{dB}}$.

13.
Neuroimage Clin ; 23: 101921, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31491830

##### RESUMO

PURPOSE: This study aims to systematically evaluate the accuracy and precision of pool size ratio (PSR) measurements from quantitative magnetization transfer (qMT) acquisitions using simplified models in the context of assessing injury-associated spatiotemporal changes in spinal cords of non-human primates. This study also aims to characterize changes in the spinal tissue pathology in individual subjects, both regionally and longitudinally, in order to demonstrate the relationship between regional tissue compositional changes and sensorimotor behavioral recovery after cervical spinal cord injury (SCI). METHODS: MRI scans were recorded on anesthetized monkeys at 9.4â¯T, before and serially after a unilateral section of the dorsal column tract. Images were acquired following saturating RF pulses at different offset frequencies. Models incorporating two pools of protons but with differing numbers of variable parameters were used to fit the data to derive qMT parameters. The results using different amounts of measured data and assuming different numbers of variable model parameters were compared. Behavioral impairments and recovery were assessed by a food grasping-retrieving task. Histological sections were obtained post mortem for validation of the injury. RESULTS: QMT fitting provided maps of pool size ratio (PSR), the relative amounts of immobilized protons exchanging magnetization compared to the "free" water. All the selected modeling approaches detected a lesion/cyst at the site of injury as significant reductions in PSR values. The regional contrasts in the PSR maps obtained using the different fittings varied, but the 2-parameter fitting results showed strong positive correlations with results from 5-parameter modeling. 2-parameter fitting results with modest (>3) RF offsets showed comparable sensitivity for detecting demyelination in white matter and loss of macromolecules in gray matter around lesion sites compared to 5-parameter fitting with fully-sampled data acquisitions. Histology confirmed that decreases of PSR corresponded to regional demyelination around lesion sites, especially when demyelination occurred along the dorsal column on the injury side. Longitudinally, PSR values of injured dorsal column tract and gray matter horns exhibited remarkable recovery that associated with behavioral improvement. CONCLUSION: Simplified qMT modeling approaches provide efficient and sensitive means to detect and characterize injury-associated demyelination in white matter tracts and loss of macromolecules in gray matter and to monitor its recovery over time.

14.
Phys Med Biol ; 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31509812

##### RESUMO

Non-contrast CT is widely employed as the first-line imaging test to evaluate for intracranial hemorrhage (ICH). Advances in MDCT technology have greatly improved the image quality of non-contrast CT (NCCT) for the detection of established, relatively large, and acute ICHs. Meanwhile, the reliability of MDCT in detecting microbleeds and chronic hemorrhage, and in predicting hemorrhagic transformation needs to be further improved. The purpose of this work was to investigate the potential use of non-spectral photon counting CT (PCCT) to address these challenges in ICH imaging. Towards this goal, the NCCT protocol of an experimental PCCT system that simulates the geometry of a general-purpose MDCT was optimized. The optimization was driven by three imaging tasks: detection of a 4.0 mm intraparenchymal hemorrhage, detection of a 1.5 mm subarachnoid hemorrhage, and discrimination of a sulcus in the insular cortex from the parenchymal background. These imaging tasks were custom-built into an anthropomorphic head phantom. Under the guidance of the frequency-dependent noise equivalent quanta and the ideal observer model detectability index d', the optimal PCD detection mode, energy threshold, and reconstruction kernel were found to be the anti-charge sharing mode, 15 keV, and an apodized ramp kernel, respectively. Compared with a clinical MDCT operated with an ICH protocol and at a matched dose level, the PCCT system provided at least 20% improvements in d' for all three ICH imaging tasks. These results demonstrated the potential benefits of non-spectral PCCT in ICH assessment.

15.
Opt Express ; 27(17): 23654-23660, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31510267

##### RESUMO

We design and fabricate a compact silicon photonic integrated circuit (PIC) for polarization diversity heterodyne coherent detection. This PIC integrates two optical gratings for fiber coupling and polarization diversity, two germanium single-ended photodetectors (PDs), and three multimode interferometers (MMIs) for power splitting and optical hybrid. The device is highly compact with a footprint of 0.68mm × 0.9mm. We test this PIC with heterodyne detection experiments of polarization division multiplexed (PDM) 32Gbaud quadrature phase shift keying (QPSK) and 16-ary quadrature amplitude modulation (16QAM) signals. The signal-signal beat interference due to square-law detection is separately mitigated with the Kramers-Kronig (KK) scheme for each of the two orthogonal polarizations. To our best knowledge, we report the first PDM-KK coherent receiver in PIC with a capability of detecting 256Gb/s 16QAM signals, which shows the most compact size among the silicon coherent receivers ever reported.

16.
Opt Express ; 27(18): 26027-26043, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31510463

##### RESUMO

Building a wide-area, high-efficiency, and accurate detection technology for air targets has become a new challenge for the construction of space situational awareness. Firstly, based on the space-based optical detection requirements for aircraft plume, the method of integrated modeling for sea/cloud background radiation characteristics based on coupling of remote sensing data and physical model is proposed, which can effectively deduce the background radiation field distribution under any environmental conditions. Specifically, combined with meteorological satellite sensor data, such as cloud top temperature, cloud type and cloud top height, three-dimensional atmospheric transmittance and atmospheric path thermal radiation texture are generated for different cloud heights and cloud phase conditions. Then, a coupled sea/cloud bidirectional reflectance model matched to the sampling of space-based detectors is established. Further, the accurate prediction model for multi-spectral imaging features of aircraft plume is built by considering the space-based full imaging chains including the complex coupling of aircraft plume, sea/cloud background, environmental atmosphere, optical system, and imaging detector. Finally, combined with the diffraction effect of the optical system, the multi-spectral imaging features of the aircraft plume are simulated under various spectral bands, flying heights, sea/cloud backgrounds, and detection angles, and the detection performances are analyzed and discussed by using the signal-to-clutter ratio (SCR). Research results show that the detection capability in the narrow band of 2.65-2.90µm and 4.25-4.50µm is better than the wide band of 3-5µm. When the aircraft flying height is greater than 5km, the aircraft plume can be detected in both narrow bands. It is more reliable to use the multispectral joint-band to detect aircraft plume in different backgrounds.

17.
Nano Lett ; 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31512886

##### RESUMO

The precise manipulation, localization, and assembly of biological and bioinspired molecules into organized structures have greatly promoted material science and bionanotechnology. Further technological innovation calls for new patternable soft materials with the long-sought qualities of environmental tolerance and functional flexibility. Here, we report a patterned amyloid material (PAM) platform for producing hierarchically ordered structures that integrate these material attributes. This platform, combining soft lithography with generic amyloid monomer inks (consisting of genetically engineered biofilm proteins dissolved in hexafluoroisopropanol), along with methanol-assisted curing, enables the spatially controlled deposition and in situ reassembly of amyloid monomers. The resulting patterned structures exhibit spectacular chemical and thermal stability and mechanical robustness under harsh conditions. The PAMs can be programmed for a vast array of multilevel functionalities, including anchoring nanoparticles, enabling diverse fluorescent protein arrays, and serving as self-supporting porous sheets for cellular growth. This PAM platform will not only drive innovation in biomanufacturing but also broaden the applications of patterned soft architectures in optics, electronics, biocatalysis, analytical regents, cell engineering, medicine, and other areas.

18.
J Mater Chem B ; 7(31): 4751-4757, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31389969

##### RESUMO

We developed a novel evaluation method for tumor-targeting characteristics of nanomedicines, average tumor-targeting index (average TTI) and "area under the tumor-targeting index-time curve" (AUTC) were established as the indicators for tumor targeting of nanomedicines based on NIR fluorescence imaging, which helps real-time monitoring of targeting ability and tumor changes in vivo without culling animals.

19.
Aesthetic Plast Surg ; 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399822

##### RESUMO

BACKGROUND: It has been reported that the injection of the hyaluronic acid (HA) into the lower lid area could improve lower eyelid retraction. However, the published studies offered few insights into the mechanism of this treatment. When the underlying mechanism is not clear, many surgeons will not trust the method enough to apply it in their clinical practice. The purpose of this article was to propose a possible explanation for the underlying mechanism of the treatment and further verify the method by a series of cases. METHODS: The authors performed a mechanical analysis on the physical impact of HA on the lower eyelid. In the clinical cases, we injected the fillers under the orbicularis muscle to correct lower lid retraction. The results were evaluated by the standardized marginal reflex distance 2 (MRD2) immediately and 9 months later. RESULTS: From October 2013 to October 2015, the injections were carried out in 27 cases (14 post-blepharoplasty and 13 involuntary). In 26 cases (96.3%), the retraction was completely corrected and did not recur through the last follow-up. The average improvement of the standardized MRD2 was 0.84 mm immediately after the injection and 1.19 mm 9 months later. Complications were not reported. CONCLUSION: Lower eyelid retraction could be treated by the injection of HA under the orbicularis muscle. The filler in this situation acted as a lifter because the filler changed the balance of force of the lower lid, forcing it to shift upward to gain the new balance. The 'lifter' mechanism could be applicable to other facial injections that generate elevating effects. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

20.
Physiol Biochem Zool ; 92(5): 463-472, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31368840

##### RESUMO

Pheromones are important sexual signals in most animals, but research into their evolution is largely biased toward insects. Lampreys are a jawless fish with a relatively well-understood pheromone communication system, and they offer a useful opportunity to study pheromone evolution in a vertebrate. Once sexually mature, male sea lamprey (Petromyzon marinus) and likely other lampreys produce and release bile acids that act as sex pheromones. Spawning males do not feed and therefore produce bile acids primarily for sexual communication, whereas larvae produce the same bile acids but for digestion, offering an opportunity to compare the evolution of bile acids produced for sexual versus nonsexual functions. We profiled eight pheromone-related bile acids in livers from larvae and males and determined the effect of life stage on intra- and interspecific variation in bile acid production. Our results indicate less variation among males than larvae within P. marinus but more variation among species for males than larvae. We postulate that bile acid production in males is shaped by directional or stabilizing selection that reduces variance within P. marinus and directional or disruptive selection that promotes diversification across species. Although our results offer support for the role of sexual selection in the evolution of lamprey pheromones, they do not eliminate possible roles of other aspects of lamprey ecology.