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1.
Article in English | MEDLINE | ID: mdl-38639609

ABSTRACT

Objective: This study aims to evaluate the clinical efficacy and safety of combining adhesion release under brachial plexus block with silver needle warm acupuncture for the treatment of frozen shoulder, compared to adhesion release under brachial plexus block alone. Methods: A total of 72 patients with frozen shoulder were randomly assigned to receive either adhesion release under brachial plexus block (control group) or adhesion release under brachial plexus block plus silver needle warm acupuncture (treatment group). Outcome measures included changes in shoulder pain scores assessed using the Visual Analog Scale (VAS), shoulder mobility scores evaluated using the Constant-Murley Score, shoulder function scores measured using the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire, and overall clinical outcomes based on a comprehensive evaluation. Both groups received functional exercise 2 days after the operation, and the treatment duration was 3 weeks. Results: The treatment group exhibited a mean reduction in shoulder pain scores of 3.2 points on the Short-form McGill pain scores, while the control group showed a reduction of 1.5 points. Shoulder mobility scores, assessed by the Constant-Murley Score, increased by an average of 18.6 points in the treatment group, compared to 9.2 points in the control group. Moreover, the treatment group achieved better shoulder function scores on the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire, with an average improvement of 25.4 points, compared to 13.8 points in the control group. Conclusion: This study provides valuable insights into the clinical efficacy of adhesion release under brachial plexus block plus silver needle warm acupuncture for frozen shoulder, there are still areas that warrant further investigation. Future research could focus on the long-term effects of the treatment, optimal treatment duration and frequency, comparison with other treatment modalities, and the inclusion of larger sample sizes to enhance the robustness of the findings.

2.
Elife ; 132024 Mar 05.
Article in English | MEDLINE | ID: mdl-38441552

ABSTRACT

The mammary gland is a unique organ that undergoes dynamic alterations throughout a female's reproductive life, making it an ideal model for developmental, stem cell and cancer biology research. Mammary gland development begins in utero and proceeds via a quiescent bud stage before the initial outgrowth and subsequent branching morphogenesis. How mammary epithelial cells transit from quiescence to an actively proliferating and branching tissue during embryogenesis and, importantly, how the branch pattern is determined remain largely unknown. Here, we provide evidence indicating that epithelial cell proliferation and onset of branching are independent processes, yet partially coordinated by the Eda signaling pathway. Through heterotypic and heterochronic epithelial-mesenchymal recombination experiments between mouse mammary and salivary gland tissues and ex vivo live imaging, we demonstrate that unlike previously concluded, the mode of branching is an intrinsic property of the mammary epithelium whereas the pace of growth and the density of ductal tree are determined by the mesenchyme. Transcriptomic profiling and ex vivo and in vivo functional studies in mice disclose that mesenchymal Wnt/ß-catenin signaling, and in particular IGF-1 downstream of it critically regulate mammary gland growth. These results underscore the general need to carefully deconstruct the different developmental processes producing branched organs.


Subject(s)
Epithelial Cells , Wnt Signaling Pathway , Mice , Animals , Epithelium/metabolism , Epithelial Cells/physiology , Cell Proliferation , Morphogenesis , Mesoderm , Mammary Glands, Animal/metabolism
3.
J Clin Invest ; 134(6)2024 Jan 18.
Article in English | MEDLINE | ID: mdl-38236642

ABSTRACT

Cancer cell plasticity contributes to therapy resistance and metastasis, which represent the main causes of cancer-related death, including in breast cancer. The tumor microenvironment drives cancer cell plasticity and metastasis, and unraveling the underlying cues may provide novel strategies for managing metastatic disease. Using breast cancer experimental models and transcriptomic analyses, we show that stem cell antigen-1 positive (SCA1+) murine breast cancer cells enriched during tumor progression and metastasis had higher in vitro cancer stem cell-like properties, enhanced in vivo metastatic ability, and generated tumors rich in Gr1hiLy6G+CD11b+ cells. In turn, tumor-educated Gr1+CD11b+ (Tu-Gr1+CD11b+) cells rapidly and transiently converted low metastatic SCA1- cells into highly metastatic SCA1+ cells via secreted oncostatin M (OSM) and IL-6. JAK inhibition prevented OSM/IL-6-induced SCA1+ population enrichment, while OSM/IL-6 depletion suppressed Tu-Gr1+CD11b+-induced SCA1+ population enrichment in vitro and metastasis in vivo. Moreover, chemotherapy-selected highly metastatic 4T1 cells maintained high SCA1+ positivity through autocrine IL-6 production, and in vitro JAK inhibition blunted SCA1 positivity and metastatic capacity. Importantly, Tu-Gr1+CD11b+ cells invoked a gene signature in tumor cells predicting shorter overall survival (OS), relapse-free survival (RFS), and lung metastasis in breast cancer patients. Collectively, our data identified OSM/IL-6/JAK as a clinically relevant paracrine/autocrine axis instigating breast cancer cell plasticity and triggering metastasis.


Subject(s)
Breast Neoplasms , Lung Neoplasms , Neoplasms, Second Primary , Spinocerebellar Ataxias , Humans , Mice , Animals , Female , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Interleukin-6/genetics , Oncostatin M , Cell Plasticity , Cell Line, Tumor , Neoplasm Recurrence, Local , Lung Neoplasms/pathology , Neoplasm Metastasis , Tumor Microenvironment
4.
J Invest Dermatol ; 144(4): 862-873.e4, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37852357

ABSTRACT

Cutaneous leishmaniasis affects 1 million people worldwide annually. Although conventional treatments primarily target the parasite, there is growing interest in host immune modulation. In this study, we investigated the impact of synthetic ß-carboline harmine (ACB1801), previously shown to be immunoregulatory in cancer, on the pathology caused by a drug-resistant Leishmania major strain causing persistent cutaneous lesions. Exposure to ACB1801 in vitro had a modest impact on parasite burden within host macrophages. Moreover, it significantly increased major histocompatibility complex II and costimulatory molecule expression on infected dendritic cells, suggesting an enhanced immune response. In vivo, ACB1801 monotherapy led to a substantial reduction in lesion development and parasite burden in infected C57BL/6 mice, comparable with efficacy of amphotericin B. Transcriptomics analysis further supported ACB1801 immunomodulatory effects, revealing an enrichment of TNF-α, IFN-γ, and major histocompatibility complex II antigen presentation signatures in the draining lymph nodes of treated mice. Flow cytometry analysis confirmed an increased frequency (1.5×) of protective CD4+IFN-γ+TNF-α+ T cells and a decreased frequency (2×) in suppressive IL-10+FoxP3- T cells at the site of infection and in draining lymph nodes. In addition, ACB1801 downregulated the aryl hydrocarbon receptor signaling, known to enhance immunosuppressive cytokines. Thus, these results suggest a potential use for ACB1801 alone or in combination therapy for cutaneous leishmaniasis.


Subject(s)
Leishmania major , Leishmaniasis, Cutaneous , Leishmaniasis , Humans , Animals , Mice , Harmine/pharmacology , Harmine/therapeutic use , Tumor Necrosis Factor-alpha , Mice, Inbred C57BL , Immunity , Mice, Inbred BALB C
5.
J Invest Dermatol ; 2023 Dec 28.
Article in English | MEDLINE | ID: mdl-38159590

ABSTRACT

The Wnt/ß-catenin pathway plays a critical role in cell fate specification, morphogenesis, and stem cell activation across diverse tissues, including the skin. In mammals, the embryonic surface epithelium gives rise to the epidermis as well as the associated appendages including hair follicles and mammary glands, both of which depend on epithelial Wnt/ß-catenin activity for initiation of their development. Later on, Wnts are thought to enhance mammary gland growth and branching, whereas in hair follicles, they are essential for hair shaft formation. In this study, we report a strong downregulation of epithelial Wnt/ß-catenin activity as the mammary bud progresses to branching. We show that forced activation of epithelial ß-catenin severely compromises embryonic mammary gland branching. However, the phenotype of conditional Lef1-deficient embryos implies that a low level of Wnt/ß-catenin activity is necessary for mammary cell survival. Transcriptomic profiling suggests that sustained high ß-catenin activity leads to maintenance of mammary bud gene signature at the expense of outgrowth/branching gene signature. In addition, it leads to upregulation of epidermal differentiation genes. Strikingly, we find a partial switch to hair follicle fate early on upon stabilization of ß-catenin, suggesting that the level of epithelial Wnt/ß-catenin signaling activity may contribute to the choice between skin appendage identities.

6.
Cell Rep ; 42(6): 112643, 2023 06 27.
Article in English | MEDLINE | ID: mdl-37318953

ABSTRACT

Morphogenesis of ectodermal organs, such as hair, tooth, and mammary gland, starts with the formation of local epithelial thickenings, or placodes, but it remains to be determined how distinct cell types and differentiation programs are established during ontogeny. Here, we use bulk and single-cell transcriptomics and pseudotime modeling to address these questions in developing hair follicles and epidermis and produce a comprehensive transcriptomic profile of cellular populations in the hair placode and interplacodal epithelium. We report previously unknown cell populations and marker genes, including early suprabasal and genuine interfollicular basal markers, and propose the identity of suprabasal progenitors. By uncovering four different hair placode cell populations organized in three spatially distinct areas, with fine gene expression gradients between them, we posit early biases in cell fate establishment. This work is accompanied by a readily accessible online tool to stimulate further research on skin appendages and their progenitors.


Subject(s)
Hair Follicle , Transcriptome , Mice , Animals , Hair Follicle/metabolism , Transcriptome/genetics , Mice, Transgenic , Epidermis/metabolism , Hair
7.
J Cell Biol ; 222(9)2023 09 04.
Article in English | MEDLINE | ID: mdl-37367826

ABSTRACT

Branching morphogenesis is an evolutionary solution to maximize epithelial function in a compact organ. It involves successive rounds of branch elongation and branch point formation to generate a tubular network. In all organs, branch points can form by tip splitting, but it is unclear how tip cells coordinate elongation and branching. Here, we addressed these questions in the embryonic mammary gland. Live imaging revealed that tips advance by directional cell migration and elongation relies upon differential cell motility that feeds a retrograde flow of lagging cells into the trailing duct, supported by tip proliferation. Tip bifurcation involved localized repression of cell cycle and cell motility at the branch point. Cells in the nascent daughter tips remained proliferative but changed their direction to elongate new branches. We also report the fundamental importance of epithelial cell contractility for mammary branching morphogenesis. The co-localization of cell motility, non-muscle myosin II, and ERK activities at the tip front suggests coordination/cooperation between these functions.


Subject(s)
Epithelial Cells , Mammary Glands, Animal , Morphogenesis , Cell Division , Cell Movement , Mammary Glands, Animal/embryology , Morphogenesis/physiology , Mammals , Myosin Type II/physiology
8.
Polymers (Basel) ; 14(23)2022 Dec 02.
Article in English | MEDLINE | ID: mdl-36501666

ABSTRACT

In the gas-assisted extrusion process, the melt inside the die is in a low-viscosity molten state, so the flow field of the gas cushion layer has a great effect on the cross-sectional shape of the micro-tube. Therefore, this study establishes the gas distribution chamber model of the gas-assisted die. Ansys Fluent software was used to simulate the gas flow field of the gas distribution chamber. The effect of the gas chamber structure on the size of the micro-tube was analyzed by the extrusion experiment. The research shows that the velocity unevenness coefficient of the gas outlet of the single gas chamber die is 11.8%, which is higher than that of the double gas chamber die. The use of a double gas chamber die can improve the stability of the gas cushion layer and the wall thickness non-uniformity of the micro-tube, which verifies the simulation results.

9.
Sci Transl Med ; 14(661): eaax8933, 2022 09 07.
Article in English | MEDLINE | ID: mdl-36070364

ABSTRACT

Brain metastasis is a complication of increasing incidence in patients with breast cancer at advanced disease stage. It is a severe condition characterized by a rapid decline in quality of life and poor prognosis. There is a critical clinical need to develop effective therapies to prevent and treat brain metastases. Here, we describe a unique and robust spontaneous preclinical model of breast cancer metastasis to the brain (4T1-BM2) in mice that has been instrumental in uncovering molecular mechanisms guiding metastatic dissemination and colonization of the brain. Key experimental findings were validated in the additional murine D2A1-BM2 model and in human MDA231-BrM2 model. Gene expression analyses and functional studies, coupled with clinical transcriptomic and histopathological investigations, identified connexins (Cxs) and focal adhesion kinase (FAK) as master molecules orchestrating breast cancer colonization of the brain. Cx31 promoted homotypic tumor cell adhesion, heterotypic tumor-astrocyte interaction, and FAK phosphorylation. FAK signaling prompted NF-κB activation inducing Lamc2 expression and laminin 332 (laminin 5) deposition, α6 integrin-mediated adhesion, and sustained survival and growth within brain parenchyma. In the MDA231-BrM2 model, the human homologous molecules CX43, LAMA4, and α3 integrin were involved. Systemic treatment with FAK inhibitors reduced brain metastasis progression. In conclusion, we report a spontaneous model of breast cancer metastasis to the brain and identified Cx-mediated FAK-NF-κB signaling as a mechanism promoting cell-autonomous and microenvironmentally controlled cell survival for brain colonization. Considering the limited therapeutic options for brain metastatic disease in cancer patients, we propose FAK as a therapeutic candidate to further pursue in the clinic.


Subject(s)
Brain Neoplasms , Breast Neoplasms , Animals , Brain/metabolism , Breast Neoplasms/genetics , Connexins/metabolism , Female , Focal Adhesion Protein-Tyrosine Kinases/genetics , Focal Adhesion Protein-Tyrosine Kinases/metabolism , Humans , Melanoma , Mice , NF-kappa B/metabolism , Quality of Life , Skin Neoplasms , Melanoma, Cutaneous Malignant
10.
Methods Mol Biol ; 2471: 1-18, 2022.
Article in English | MEDLINE | ID: mdl-35175589

ABSTRACT

Mammary gland development starts during embryogenesis, and the process continues after birth. During development, the mammary gland undergoes massive morphological and physiological alterations including growth, invasion, and branching morphogenesis providing an ideal model for stem cell and cancer biology studies. Great efforts have been made in understanding mammary gland development during puberty and adulthood; however, the process during embryogenesis is still elusive. One reason is that the tools to study tissue dynamics during development are limited, which is partially due to the lack of an ex vivo culture method. Here we describe an updated organ culture protocol of the murine embryonic mammary gland. This powerful tool allows monitoring of growth and branching morphogenesis of mammary gland ex vivo by live imaging. In addition, we introduce a novel method for culturing intact, stroma-free mammary rudiments from late gestation mouse embryos in 3D in Matrigel. This approach can be used to identify the direct stromal cues for branching morphogenesis.


Subject(s)
Epithelial Cells , Mammary Glands, Animal , Animals , Female , Mice , Morphogenesis , Organ Culture Techniques , Pregnancy
11.
Entropy (Basel) ; 23(9)2021 Sep 18.
Article in English | MEDLINE | ID: mdl-34573852

ABSTRACT

The accuracy and efficiency of sound field calculations highly concern issues of hydroacoustics. Recently, one-dimensional spectral methods have shown high-precision characteristics when solving the sound field but can solve only simplified models of underwater acoustic propagation, thus their application range is small. Therefore, it is necessary to directly calculate the two-dimensional Helmholtz equation of ocean acoustic propagation. Here, we use the Chebyshev-Galerkin and Chebyshev collocation methods to solve the two-dimensional Helmholtz model equation. Then, the Chebyshev collocation method is used to model ocean acoustic propagation because, unlike the Galerkin method, the collocation method does not need stringent boundary conditions. Compared with the mature Kraken program, the Chebyshev collocation method exhibits a higher numerical accuracy. However, the shortcoming of the collocation method is that the computational efficiency cannot satisfy the requirements of real-time applications due to the large number of calculations. Then, we implemented the parallel code of the collocation method, which could effectively improve calculation effectiveness.

12.
Entropy (Basel) ; 23(6)2021 Jun 02.
Article in English | MEDLINE | ID: mdl-34199538

ABSTRACT

The normal mode model is important in computational atmospheric acoustics. It is often used to compute the atmospheric acoustic field under a time-independent single-frequency sound source. Its solution consists of a set of discrete modes radiating into the upper atmosphere, usually related to the continuous spectrum. In this article, we present two spectral methods, the Chebyshev-Tau and Chebyshev-Collocation methods, to solve for the atmospheric acoustic normal modes, and corresponding programs are developed. The two spectral methods successfully transform the problem of searching for the modal wavenumbers in the complex plane into a simple dense matrix eigenvalue problem by projecting the governing equation onto a set of orthogonal bases, which can be easily solved through linear algebra methods. After the eigenvalues and eigenvectors are obtained, the horizontal wavenumbers and their corresponding modes can be obtained with simple processing. Numerical experiments were examined for both downwind and upwind conditions to verify the effectiveness of the methods. The running time data indicated that both spectral methods proposed in this article are faster than the Legendre-Galerkin spectral method proposed previously.

13.
J Cell Biol ; 220(8)2021 08 02.
Article in English | MEDLINE | ID: mdl-34042944

ABSTRACT

The mammary gland develops from the surface ectoderm during embryogenesis and proceeds through morphological phases defined as placode, hillock, bud, and bulb stages followed by branching morphogenesis. During this early morphogenesis, the mammary bud undergoes an invagination process where the thickened bud initially protrudes above the surface epithelium and then transforms to a bulb and sinks into the underlying mesenchyme. The signaling pathways regulating the early morphogenetic steps have been identified to some extent, but the underlying cellular mechanisms remain ill defined. Here, we use 3D and 4D confocal microscopy to show that the early growth of the mammary rudiment is accomplished by migration-driven cell influx, with minor contributions of cell hypertrophy and proliferation. We delineate a hitherto undescribed invagination mechanism driven by thin, elongated keratinocytes-ring cells-that form a contractile rim around the mammary bud and likely exert force via the actomyosin network. Furthermore, we show that conditional deletion of nonmuscle myosin IIA (NMIIA) impairs invagination, resulting in abnormal mammary bud shape.


Subject(s)
Actomyosin/metabolism , Cell Movement , Epithelial Cells/metabolism , Mammary Glands, Animal/metabolism , Mechanotransduction, Cellular , Animals , Cell Proliferation , Epithelial Cells/ultrastructure , Female , Gene Expression Regulation, Developmental , Gestational Age , Hypertrophy , Keratinocytes/metabolism , Keratinocytes/ultrastructure , Mammary Glands, Animal/embryology , Mammary Glands, Animal/ultrastructure , Mice, Inbred C57BL , Mice, Transgenic , Microscopy, Confocal , Microscopy, Electron, Scanning , Microscopy, Fluorescence , Morphogenesis
14.
J Mammary Gland Biol Neoplasia ; 25(4): 409-416, 2020 12.
Article in English | MEDLINE | ID: mdl-33009602

ABSTRACT

Branching morphogenesis of the murine mammary gland starts during late embryogenesis. It is regulated by the signals emanating both from the epithelium and the mesenchyme, yet the molecular mechanisms regulating this process remain poorly understood. We have previously developed a unique whole organ culture technique for embryonic mammary glands, which provides a powerful tool to monitor and manipulate branching morphogenesis ex vivo. Nowadays, RNA sequencing and other transcriptional profiling techniques provide robust methods to identify components of gene regulatory networks driving branching morphogenesis. However, validation of the candidate genes still mainly depends on the use of the transgenic mouse models, especially in mammary gland studies. By comparing different serotypes of recombinant adeno-associated virus (rAAVs), we found out that rAAVs provide sufficient efficiency for gene transfer with different tissue preferences depending on the serotypes of the virus. AAV-2 and AAV-8 preferentially target epithelial and mesenchymal compartments, respectively, while AAV-9 infects both tissues. Here, we describe a protocol for AAV-mediated gene transfer in ex vivo cultured murine embryonic mammary gland facilitating gene function studies on mammary gland branching morphogenesis.


Subject(s)
Gene Transfer Techniques , Mammary Glands, Animal/growth & development , Morphogenesis/genetics , Organ Culture Techniques/methods , Animals , Dependovirus/genetics , Embryo, Mammalian , Female , Gene Expression Regulation, Developmental , Genetic Vectors/genetics , Mice , Serogroup
15.
Oncogene ; 38(15): 2814-2829, 2019 04.
Article in English | MEDLINE | ID: mdl-30546090

ABSTRACT

Neoadjuvant and adjuvant chemotherapies provide survival benefits to breast cancer patients, in particular in estrogen receptor negative (ER-) cancers, by reducing rates of recurrences. It is assumed that the benefits of (neo)adjuvant chemotherapy are due to the killing of disseminated, residual cancer cells, however, there is no formal evidence for it. Here, we provide experimental evidence that ER- breast cancer cells that survived high-dose Doxorubicin and Methotrexate based chemotherapies elicit a state of immunological dormancy. Hallmark of this dormant phenotype is the sustained activation of the IRF7/IFN-ß/IFNAR axis subsisting beyond chemotherapy treatment. Upregulation of IRF7 in treated cancer cells promoted resistance to chemotherapy, reduced cell growth and induced switching of the response from a myeloid derived suppressor cell-dominated immune response to a CD4+/CD8+ T cell-dependent anti-tumor response. IRF7 silencing in tumor cells or systemic blocking of IFNAR reversed the state of dormancy, while spontaneous escape from dormancy was associated with loss of IFN-ß production. Presence of IFN-ß in the circulation of ER- breast cancer patients treated with neoadjuvant Epirubicin chemotherapy correlated with a significantly longer distant metastasis-free survival. These findings establish chemotherapy-induced immunological dormancy in ER- breast cancer as a novel concept for (neo)adjuvant chemotherapy activity, and implicate sustained activation of the IRF7/IFN-ß/IFNAR pathway in this effect. Further, IFN-ß emerges as a potential predictive biomarker and therapeutic molecule to improve outcome of ER- breast cancer patients treated with (neo)adjuvant chemotherapy.


Subject(s)
Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Interferon Regulatory Factor-7/metabolism , Interferon Type I/metabolism , Animals , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Biomarkers, Tumor/metabolism , Cell Line, Tumor , Chemotherapy, Adjuvant/methods , Doxorubicin/pharmacology , Epirubicin/pharmacology , Female , Humans , Interferon-beta/metabolism , Methotrexate/pharmacology , Mice , Mice, Inbred BALB C , Mice, Inbred NOD , Mice, Nude , Mice, SCID , Neoadjuvant Therapy/methods , Neoplasm Recurrence, Local/metabolism , Receptor, ErbB-2/metabolism
16.
Langmuir ; 34(33): 9701-9710, 2018 08 21.
Article in English | MEDLINE | ID: mdl-30058809

ABSTRACT

The relationship between collective properties and performance of antiagglomerants (AAs) used in hydrate management is handled using molecular dynamics simulations and enhanced sampling techniques. A thin film of AAs adsorbed at the interface between one flat sII methane hydrate substrate and a fluid hydrocarbon mixture containing methane and n-dodecane is studied. The AA considered is a surface-active compound with a complex hydrophilic head that contains both amide and tertiary ammonium cation groups and hydrophobic tails. At a sufficiently high AA density, the interplay between the surfactant layer and the liquid hydrocarbon excludes methane from the interfacial region. In this scenario, we combine metadynamics and umbrella sampling frameworks to study accurately the free-energy landscape and the equilibrium rates associated with the transport of one methane molecule across the AA film. We observe that the local configurational changes of the liquid hydrocarbon packed within the AA film are associated with high free-energy barriers for methane transport. The time scales estimated for the transport of methane across the AA film can be, in some cases, comparable to those reported in the literature for the growth of hydrates, suggesting that one possible mechanism by which AAs delay the formation of hydrate plugs could be providing a barrier to methane transport. Considering the interplay between the structural design and collective properties of AAs might be of relevance to improve their performance in flow assurance.

17.
J Phys Chem Lett ; 9(12): 3491-3496, 2018 Jun 21.
Article in English | MEDLINE | ID: mdl-29870264

ABSTRACT

In gas clathrate hydrates, inclusion gas molecules stabilize crystalline water structures. In addition to being fundamentally interesting, gas hydrates attract significant practical attention because of their possible application in various high-tech technologies. However, gas hydrates pose health, safety, and environmental risks when they form within oil and gas pipelines, as well as within hydrocarbon-producing and treatment facilities. Among available strategies to control and sometimes prevent hydrate plug formation is the use of surface-active low-molecular-weight compounds, known as antiagglomerants (AAs). AAs prevent the agglomeration of small hydrate particles into large plugs. It is not clear whether AAs promote or frustrate hydrate growth. We present two molecular mechanisms by which AAs promote and frustrate, respectively, hydrate growth. Our results could lead to innovative methodologies for managing hydrates in high-tech applications, as well as for securing the safety of oil and gas operations.

18.
Comput Intell Neurosci ; 2017: 8348671, 2017.
Article in English | MEDLINE | ID: mdl-29250109

ABSTRACT

Convolutional neural networks have proven to be highly successful in applications such as image classification, object tracking, and many other tasks based on 2D inputs. Recently, researchers have started to apply convolutional neural networks to video classification, which constitutes a 3D input and requires far larger amounts of memory and much more computation. FFT based methods can reduce the amount of computation, but this generally comes at the cost of an increased memory requirement. On the other hand, the Winograd Minimal Filtering Algorithm (WMFA) can reduce the number of operations required and thus can speed up the computation, without increasing the required memory. This strategy was shown to be successful for 2D neural networks. We implement the algorithm for 3D convolutional neural networks and apply it to a popular 3D convolutional neural network which is used to classify videos and compare it to cuDNN. For our highly optimized implementation of the algorithm, we observe a twofold speedup for most of the 3D convolution layers of our test network compared to the cuDNN version.


Subject(s)
Computer Graphics , Neural Networks, Computer , Image Processing, Computer-Assisted/methods , Video Recording
19.
Sci Rep ; 7(1): 5049, 2017 07 11.
Article in English | MEDLINE | ID: mdl-28698625

ABSTRACT

Mammary gland development begins with the appearance of epithelial placodes that invaginate, sprout, and branch to form small arborized trees by birth. The second phase of ductal growth and branching is driven by the highly invasive structures called terminal end buds (TEBs) that form at ductal tips at the onset of puberty. Ectodysplasin (Eda), a tumor necrosis factor-like ligand, is essential for the development of skin appendages including the breast. In mice, Eda regulates mammary placode formation and branching morphogenesis, but the underlying molecular mechanisms are poorly understood. Fibroblast growth factor (Fgf) receptors have a recognized role in mammary ductal development and stem cell maintenance, but the ligands involved are ill-defined. Here we report that Fgf20 is expressed in embryonic mammary glands and is regulated by the Eda pathway. Fgf20 deficiency does not impede mammary gland induction, but compromises mammary bud growth, as well as TEB formation, ductal outgrowth and branching during puberty. We further show that loss of Fgf20 delays formation of Eda-induced supernumerary mammary buds and normalizes the embryonic and postnatal hyperbranching phenotype of Eda overexpressing mice. These findings identify a hitherto unknown function for Fgf20 in mammary budding and branching morphogenesis.


Subject(s)
Ectodysplasins/metabolism , Fibroblast Growth Factors/genetics , Mammary Glands, Animal/growth & development , Sexual Maturation , Animals , Cell Proliferation , Female , Fibroblast Growth Factors/deficiency , Fibroblast Growth Factors/metabolism , Gene Expression Regulation, Developmental , Mammary Glands, Animal/embryology , Mice, Inbred C57BL , Phenotype
20.
Langmuir ; 33(9): 2263-2274, 2017 03 07.
Article in English | MEDLINE | ID: mdl-28110536

ABSTRACT

Molecular dynamics simulations were employed to study the structure of molecularly thin films of antiagglomerants adsorbed at the interface between sII methane hydrates and a liquid hydrocarbon. The liquid hydrocarbon was composed of dissolved methane and higher-molecular-weight alkane such as n-hexane, n-octane, and n-dodecane. The antiagglomerants considered were surface-active compounds with three hydrophobic tails and a complex hydrophilic head that contains both amide and tertiary ammonium cation groups. The length of the hydrophobic tails and the surface density of the compounds were changed systematically. The results were analyzed in terms of the preferential orientation of the antiagglomerants, density distributions of various molecular compounds, and other molecular-level properties. At low surface densities, the hydrophobic tails do not show preferred orientation, irrespectively of the tail length. At sufficiently high surface densities, our simulations show pronounced differences in the structure of the interfacial film depending on the molecular features and on the type of hydrocarbons present in the system. Some antiagglomerants are found to pack densely at the interface and exclude methane from the interfacial region. Under these conditions, the antiagglomerant film resembles a frozen interface. The hydrophobic tails of the antiagglomerants that show this feature has a length comparable to that of the n-dodecane in the liquid phase. It is possible that the structured interfacial layer is in part responsible for determining the performance of antiagglomerants in flow-assurance applications. The simulation results are compared against experimental data obtained with the rocking cell apparatus. It was found that the antiagglomerants for which our simulations suggest evidence of a frozen interface at sufficiently high surface densities are those that show better performance in rocking cell experiments.

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