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The viscoelasticity of a carbon nanotube (CNT)-laden air-water interface was characterized using two different experimental methods. The first experimental method used a Langmuir-Pockels (LP) trough coupled with a pair of oscillating barriers. The second method is termed the Bicone-Trough (BT) method, where a LP trough was custom-built and fit onto a rheometer equipped with a bicone fixture to standardize the preparation and conditioning of a particle-laden interface especially at high particle coverages. The performance of both methods was evaluated by performing Fast Fourier Transform (FFT) analysis to calculate the signal-to-noise ratios (SNR). Overall, the rheometer-based BT method offered better strain control and considerably higher SNRs compared to the Oscillatory Barriers (OB) method that oscillated barriers with relatively limited positional and speed control. For a CNT surface coverage of 165 mg/m2 and a frequency of 100 mHz, the interfacial shear modulus obtained from the OB method increased from 39 to 57 mN/m as the normal strain amplitude increased from 1 to 3%. No linear viscoelastic regime was experimentally observed for a normal strain as small as 0.5%. In the BT method, a linear regime was observed below a shear strain of 0.1%. The interfacial shear modulus decreased significantly from 96 to 2 mN/m as the shear strain amplitude increased from 0.025 to 10%.
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Materials that exhibit yielding behavior are used in many applications, from spreadable foods and cosmetics to direct write three-dimensional printing inks and filled rubbers. Their key design feature is the ability to transition behaviorally from solid to fluid under sufficient load or deformation. Despite its widespread applications, little is known about the dynamics of yielding in real processes, as the nonequilibrium nature of the transition impedes understanding. We demonstrate an iteratively punctuated rheological protocol that combines strain-controlled oscillatory shear with stress-controlled recovery tests. This technique provides an experimental decomposition of recoverable and unrecoverable strains, allowing for solid-like and fluid-like contributions to a yield stress material's behavior to be separated in a time-resolved manner. Using this protocol, we investigate the overshoot in loss modulus seen in materials that yield. We show that this phenomenon is caused by the transition from primarily solid-like, viscoelastic dissipation in the linear regime to primarily fluid-like, plastic flow at larger amplitudes. We compare and contrast this with a viscoelastic liquid with no yielding behavior, where the contribution to energy dissipation from viscous flow dominates over the entire range of amplitudes tested.
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INTRODUCTION: Recent research on tumorigenesis and progression has opened up an array of novel molecular mechanisms in the form of interactions between cellular non-coding RNAs (long non-coding RNA[lncRNA]/microRNA [miRNA]) and coding transcripts that regulate health and disease. Endometrial cancer (EC) is a prominent gynecological malignancy with a high incidence rate and poorly known etiology and prognostic factors that hinder the success of disease management. The emerging role of lncRNA-miRNA-mRNA interactions and their dysregulation in the pathophysiology of EC has been elucidated in many recent studies. METHODS: A thorough literature review was conducted to explore information about lncRNA-miRNA-mRNA axes in EC. RESULTS: Several lncRNAs act as molecular sponges that sequester various tumor suppressor miRNAs to inhibit their function, leading to the dysregulation of their target mRNA transcripts that contribute to the EC regulation. CONCLUSIONS: This review summarizes these networks of molecular mechanisms and their contribution to different aspects of endometrial carcinogenesis, leading to a better conceptualization of the molecular pathways that underlie the disease and helping establish novel diagnostic biomarkers and therapeutic intervention points to aid the curative intent of EC.
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Neoplasias do Endométrio , MicroRNAs , RNA Longo não Codificante , Biomarcadores/metabolismo , Carcinogênese/genética , Neoplasias do Endométrio/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/metabolismoRESUMO
Background: Research in India has seldom studied caregivers' perceptions, experiences, and needs for information and personal support after an autism spectrum disorder (ASD) diagnosis. Objectives: The objectives of the study were to understand the perceived barriers for obtaining a diagnosis and the perspectives and experiences of parents of children with autism. Materials and Methods: Parents with a diagnosed ASD child (within a year of diagnosis) in the 3-8 years range were recruited from the Pediatric Psychology and Neurodevelopmental Clinic from a tertiary care teaching hospital in North India. An interview guide elicited information about experiences regarding obtaining an ASD diagnosis, perceived barriers and facilitators, reactions to diagnosis, postdiagnostic family and community experiences, and stress experienced by parents. Qualitative responses were analyzed using thematic analysis. Participants were recruited till there was a saturation of themes. The ethics clearance was provided by the institutional review board. Results: Twenty-eight caregivers of children with ASD were recruited for the study. Overall, nine themes were identified from the qualitative analysis of the interviews: two before diagnosis (delayed help-seeking and experiences with healthcare), one at the time of diagnosis disclosure (heightened emotional response to diagnosis), and six themes after the diagnosis (increased stress, behavioral challenges, deterioration in family relationships, negative attitudes of the family, seeking support, and moving forward with hope for the future). Conclusions: There are several barriers and gaps in the autism-related available services in the country, and there is a need to provide inclusive, supportive, culturally sensitive, and family-centered model of care for parents raising children with ASD.
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Transtorno do Espectro Autista , Poder Familiar , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/psicologia , Criança , Acessibilidade aos Serviços de Saúde , Humanos , Índia , Poder Familiar/psicologia , Pesquisa QualitativaRESUMO
Recent models have predicted entangled polymer solutions could shear band due to unstable flow-induced demixing. This work provides the first experimental probe of the in situ concentration profile of entangled polymer solutions under shear. At shear rates above a critical value, we show that the concentration and velocity profiles can develop bands, in quantitative agreement with steady-state model predictions. These findings highlight the critical importance of flow-concentration coupling in entangled polymer solutions.
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Substantial epidemiological studies have shown an association of obesity with the common gynecological malignancy, endometrial cancer. The relevant interactions and contribution of estradiol and the adipose cytokine, leptin, in endometrial lesions are not completely understood. Suitable animal models to understand the physiological response of uterine tissue to the combined effects of estradiol-leptin are lacking. To investigate the effect of estradiol-leptin crosstalk on gene expression and associated altered pathways, we established an ovariectomized mouse model, treated with 17-ß estradiol (0.1 µg/mouse subcutaenously., for every 12 h) and/or recombinant mouse leptin (1 µg/g Bwt intraperitoneally., for every 12 h) for 4 h, 20 h, and 40 h. Gene expressions by semi-quantitative RT-PCR, uterine tissue protein phosphorylation status by western blotting and promoter methylation were analyzed in estradiol, progesterone insufficient animals. Semi-quantitative RT-PCR demonstrated significantly increased expression of Esr, Igf1, Igfbp3, Vegfr1, and Vegf, and significantly decreased expression of Mmp9 after co-treatment with estradiol and leptin, indicating a common transcriptional network regulated by the treatments. Ovariectomy-induced histomorphological changes were only reversed by estradiol. Methylation-specific PCR, analyzing methylation of CpG sites of Vegfa, Pgr, and Igf1, revealed that transcriptional regulation after hormonal treatments is independent of methylation at the examined CpG sites. Western blot confirmed the increased expression of PSTAT-3 (Ser-727) and PERK1/2 proteins after estradiol + leptin treatment, confirming the estradiol + leptin cross-talk hypothesis. In conclusion, our in vivo studies determined specific gene expression and signaling protein changes, and further unraveled the molecular targets of estradiol + leptin that may perturb endometrial homeostasis and lead to endometrial hyperplasia development in the chronic stimulated state.
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Metilação de DNA/efeitos dos fármacos , Estradiol/farmacologia , Leptina/farmacologia , Menopausa , Regiões Promotoras Genéticas/efeitos dos fármacos , Útero/efeitos dos fármacos , Animais , Combinação de Medicamentos , Endométrio/efeitos dos fármacos , Endométrio/patologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Menopausa/efeitos dos fármacos , Menopausa/genética , Camundongos , Modelos Animais , Ovariectomia , Útero/patologiaRESUMO
Protein Tyrosine Phosphatase H1/Protein Tyrosine Phosphatase Non receptor Type 3 (PTPH1/PTPN3) is upregulated and/or mutated in glioma, ovarian, gastric, and colorectal cancers. Previous studies have documented that PTPH1-associated breast cancers exhibit enhanced sensitivity to tamoxifen and tyrosine kinase inhibitors through dephosphorylation of ER and epidermal growth factor receptor, respectively. Owing to the key role that PTPH1 plays as a biomarker in predicting the response of chemotherapeutic drugs and lack of studies on Indian breast cancer patients, the present study investigated PTPH1 protein expression and its relationship to clinical features, ER/PR/HER2/neu statuses, and methylation of promoter in breast cancer tissues (n = 67) among Indian population by immunohistochemistry and methylation specific polymerase chain reaction. PTPH1 expression was upregulated in 58.21% (39/67) and downregulated in the rest of tumor specimens, and it correlated with ER, PR, and HER2/neu statuses with p values of <0.0001, 0.0113, and 0.0448, respectively. Additionally, we found that the 2 kb region upstream of PTPH1 gene harbored CpG sites within, and was ubiquitously methylated in breast cancer (n = 13), colon cancer tissue (n = 1), uterine cancer tissue (n = 1), normal breast tissue (n = 1) in addition to Hela and MCF7 cell lines. In conclusion, our data showed a strong correlation of the PTPH1 status with the ER and ubiquitous nature of PTPH1 promoter methylation at specific CpG sites irrespective of cancer types and protein expression. Our findings underscore the clinical relevance of PTPH1 expression in Indian patients and warrant additional studies to explore the importance of ubiquitously methylated promoter at specific CpG sites in upstream of the PTPH1 gene.
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Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Ilhas de CpG , Metilação de DNA , Imuno-Histoquímica , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Proteína Tirosina Fosfatase não Receptora Tipo 3/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/enzimologia , Feminino , Células HeLa , Humanos , Índia , Células MCF-7 , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Proteína Tirosina Fosfatase não Receptora Tipo 3/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Estudos RetrospectivosRESUMO
The aim of this study was to evaluate whether Gemin 5, Cpeb, Xrn1, and Stau1 expression in rodent ovaries and uterine tissues is dependent on gonadotropins, steroid hormones, and leptin in the superovulation and ovariectomized mouse models of menopause. Treatment of pregnant mare serum gonadotropin-primed rats with human chorionic gonadotropin (hCG) significantly induced Stau1 and Gemin 5 messenger RNA expression in rat ovaries. Gemin 5 expression in ovaries was sustained at relatively high levels at 12 h and 24 h post hCG treatment compared to Stau1, suggesting its role in follicle development, ovulation, and luteogenesis in rat ovaries. Induced expression of Stau1 and Gemin 5 in the uterine tissue post hCG treatment at 12 h and 24 h-the duration between ovulation and post-ovulation-suggests their regulation by hCG and/or ovarian steroids, which are required for pregnancy establishment and maintenance. Cpeb expression was significantly higher (p < 0.05) in the uterine tissues after combined treatment of estradiol and leptin at 4 h. Further, the significant upregulation of uterine Gemin 5 and Xrn1 by the synergistic activities of leptin and estradiol at 40 h in ovariectomized mice establishes them as targets of cross-talk. Although these are preliminary data, the combination of Gemin 5, Cpeb, Xrn1, and Stau1 transcript alterations in rodent ovaries and uterine tissue displayed in two different experimental models underscore their importance as therapeutic targets for anovulation or in overcoming endometrial homeostasis disturbances during pregnancy due to obesity.
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Proteínas de Ligação a RNA/metabolismo , Proteínas do Complexo SMN/metabolismo , Animais , Gonadotropina Coriônica , Proteínas do Citoesqueleto/metabolismo , Estradiol/metabolismo , Exorribonucleases/genética , Exorribonucleases/metabolismo , Feminino , Regulação da Expressão Gênica/genética , Leptina/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Ovariectomia , Ovário/metabolismo , Ovário/patologia , Progesterona/sangue , Proteínas de Ligação a RNA/genética , Ratos , Ratos Wistar , Proteínas do Complexo SMN/genética , Superovulação , Útero/efeitos dos fármacos , Útero/metabolismo , Útero/patologia , Fatores de Poliadenilação e Clivagem de mRNA/genética , Fatores de Poliadenilação e Clivagem de mRNA/metabolismoRESUMO
Contemporary molecular biology research tools have enriched numerous areas of biomedical research that address challenging diseases, including endocrine cancers (pituitary, thyroid, parathyroid, adrenal, testicular, ovarian, and neuroendocrine cancers). These tools have placed several intriguing clues before the scientific community. Endocrine cancers pose a major challenge in health care and research despite considerable attempts by researchers to understand their etiology. Microarray analyses have provided gene signatures from many cells, tissues, and organs that can differentiate healthy states from diseased ones, and even show patterns that correlate with stages of a disease. Microarray data can also elucidate the responses of endocrine tumors to therapeutic treatments. The rapid progress in next-generation sequencing methods has overcome many of the initial challenges of these technologies, and their advantages over microarray techniques have enabled them to emerge as valuable aids for clinical research applications (prognosis, identification of drug targets, etc.). A comprehensive review describing the recent advances in next-generation sequencing methods and their application in the evaluation of endocrine and endocrine-related cancers is lacking. The main purpose of this review is to illustrate the concepts that collectively constitute our current view of the possibilities offered by next-generation sequencing technological platforms, challenges to relevant applications, and perspectives on the future of clinical genetic testing of patients with endocrine tumors. We focus on recent discoveries in the use of next-generation sequencing methods for clinical diagnosis of endocrine tumors in patients and conclude with a discussion on persisting challenges and future objectives.
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Neoplasias das Glândulas Endócrinas/genética , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA , Neoplasias das Glândulas Endócrinas/patologia , Genoma Humano , HumanosRESUMO
The posterior ligamentous complex plays a pivotal role in spinal stability during complex movements, especially at the cervical vertebral level. Its disruption leads to the development of post-laminectomy kyphosis. The present case emphasizes the challenges in managing post-laminectomy kyphosis, restoring spinal alignment, and the importance of the posterior tension band as a spine stabilizer. A 19-year-old male underwent C2-C5 laminectomy for cervical C3 neurofibroma at an outside hospital. The patient remained stable for five months and then developed cervical kyphosis, leading to myelopathy. Clinical examination revealed significant neurological deficits, including spasticity, clonus, loss of hand dexterity, and sensory abnormalities. Imaging revealed C3 retrolisthesis with severe cervical kyphosis, cord compression, and myelomalacia. The management involved cervical traction with gradual increments in the weight and correction of the cervical sagittal balance. Principles of kyphotic deformity correction were applied, and C2 pedicle with C3-C5 lateral mass fixation was performed. The patient's modified Japanese Orthopaedic Association score improved from 10 to 16 at six months' follow-up. Post-laminectomy, the disruption of the posterior ligamentous complex increases the range of motion, particularly in the cervical spine, leading to instability and kyphosis. Surgical interventions such as laminoplasty, laminotomy, and laminectomy with posterior cervical fusion aim to mitigate the risk of kyphosis, with techniques such as bone-to-bone ligament-preserving laminoplasty and ultrasonic bone scalpel showing promise in further reducing the risk of kyphosis. The key determinant for the prevention of kyphosis is the integrity of the posterior ligamentous complex. The management of cervical kyphosis includes appropriate pre-operative planning, which includes the evaluation of cervical and spinopelvic parameters. For a posterior spinal approach, one may choose to consider laminotomy, laminoplasty, or laminectomy along with posterior cervical fusion.
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Pyroclastic density currents (PDCs) are the most lethal of all volcanic hazards. An ongoing challenge is to accurately forecast their run-out distance such that effective mitigation strategies can be implemented. Central to this goal is an understanding of the flow mobility-a quantitative rheological model detailing how the high temperature gas-pyroclast mixtures propagate. This is currently unknown, yet critical to accurately forecast the run-out distance. Here, we use a laboratory apparatus to perform rheological measurements on real gas-pyroclast mixtures at dynamic conditions found in concentrated to intermediate pumice-rich PDCs. We find their rheology to be non-Newtonian featuring (i) a yield stress where deposition occurs; (ii) shear-thinning behavior that promotes channel formation and local increases in velocity and (iii) shear-thickening behavior that promotes decoupling and potential co-PDC plume formation. We provide a universal regime diagram delineating these behaviors and illustrating how flow can transition between them during transport.
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Among the known nuclear exportins, CRM1 is the most studied prototype. Dysregulation of CRM1 occurs in many cancers, hence, understanding the role of CRM1 in cancer can help in developing synergistic therapeutics. The study investigates how CRM1 affects prostate cancer growth and survival. It examines the role of CRM1 in regulating androgen receptor (AR) and DNA repair in prostate cancer. Our findings reveal that CRM1 influences AR mRNA and protein stability, leading to a loss of AR protein upon CRM1 inhibition. Furthermore, it highlights the involvement of HSP90 alpha, a known AR chaperone, in the CRM1-dependent regulation of AR protein stability. The combination of CRM1 inhibition with an HSP90 inhibitor demonstrates potent effects on decreasing prostate cancer cell growth and survival. The study further explores the influence of CRM1 on DNA repair proteins and proposes a strategy of combining CRM1 inhibitors with DNA repair pathway inhibitors to decrease prostate cancer growth. Overall, the findings suggest that CRM1 plays a crucial role in prostate cancer growth, and a combination of inhibitors targeting CRM1 and DNA repair pathways could be a promising therapeutic strategy.
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Among the diverse areas of 3D printing, high-quality silicone printing is one of the least available and most restrictive. However, silicone-based components are integral to numerous advanced technologies and everyday consumer products. We developed a silicone 3D printing technique that produces precise, accurate, strong, and functional structures made from several commercially available silicone formulations. To achieve this level of performance, we developed a support material made from a silicone oil emulsion. This material exhibits negligible interfacial tension against silicone-based inks, eliminating the disruptive forces that often drive printed silicone features to deform and break apart. The versatility of this approach enables the use of established silicone formulations in fabricating complex structures and features as small as 8 micrometers in diameter.
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Implantable patient-specific devices are the next frontier of personalized medicine, positioned to improve the quality of care across multiple clinical disciplines. Translation of patient-specific devices requires time- and cost-effective processes to design, verify and validate in adherence to FDA guidance for medical device manufacture. In this study, we present a generalized strategy for selective laser sintering (SLS) of patient-specific medical devices following the prescribed guidance for additive manufacturing of medical devices issued by the FDA in 2018. We contextualize this process for manufacturing an Airway Support Device, a life-saving tracheal and bronchial implant restoring airway patency for pediatric patients diagnosed with tracheobronchomalacia and exhibiting partial or complete airway collapse. The process covers image-based modeling, design inputs, design verification, material inputs and verification, device verification, and device validation, including clinical results. We demonstrate how design and material assessment lead to verified Airway Support Devices that achieve desired airway patency and reduction in required Positive End-Expiratory Pressure (PEEP) after patient implantation. We propose this process as a template for general quality control of patient-specific, 3D printed implants.
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Brônquios , Traqueia , Criança , Humanos , Impressão TridimensionalRESUMO
Obesity increases the risk of developing cancers for both males and females. This study investigated potential crosstalk between estradiol and leptin signaling pathways within the endometrium of high-fat-diet-induced obese ovariectomized mice to gain insight into possible links between obesity and endometrial cancer. We administered 17-ß estradiol (0.2 µg/mouse subcutaneously) and/or recombinant mouse leptin (1 µg/g Bwt intraperitoneally.,) for 20 h to high-fat-diet-induced obese ovariectomized mice. The uterine tissues of experimental animals after treatments were studied by histological, immunohistochemical, quantitative real-time PCR (gene/miRNAs), and methylation-specific PCR analyses. Quantitative real-time PCR analysis revealed significantly increased expression of Cyclin d1, Esr1, Igf1, Igfbp2, Vegf, Oct4, and Pgr after estradiol and leptin co-treatment. Methylation-specific PCR results indicated that the hormonal dependent transcriptional regulation of Vegf, Igf1, and Pgr is independent of promoter methylation. The decreased expression of mmu- miR-204-5p after estradiol and leptin treatments correlated with the increased expression of long non-coding RNA Neat1. Insilico analysis confirmed the interaction of Neat1 and mmu- miR-204-5p and gene targets of mmu-miR-204-5p, including Igf1 were analyzed in this study. Immunohistochemical analyses revealed subcellular localization and increased expression of ESR, VEGF, phospho-Estrogen Receptor-α (pTyr537), and LEPR proteins following estradiol and leptin exposure. Overall, the data from our in vivo studies suggest the regulation of Neat1-mmu-miR-204-5p- Igf1 axis and associated gene expression changes in uterine tissue after estradiol and leptin co-treatment. In humans, long-term exposure to estradiol and leptin can alter endometrial homeostasis through the NEAT1-miR-204-5p-Igf1 axis and favor carcinogenic pathways, which provide mechanistic insight into the obesity-associated endometrial cancer.
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Neoplasias do Endométrio/patologia , Estradiol/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Leptina/metabolismo , MicroRNAs/genética , Obesidade/complicações , RNA Longo não Codificante/genética , Animais , Dieta Hiperlipídica , Neoplasias do Endométrio/etiologia , Neoplasias do Endométrio/metabolismo , Estrogênios/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Fator de Crescimento Insulin-Like I/genética , Camundongos , Camundongos Obesos , OvariectomiaRESUMO
Hundreds of YouTube videos show people running on cornstarch suspensions demonstrating that dense shear thickening suspensions solidify under impact. Such processes are mimicked by impacting and pulling out a plate from the surface of a thickening cornstarch suspension. Here, using both experiments and simulations, we show that applying fast oscillatory shear transverse to the primary impact or extension directions tunes the degree of solidification. The forces acting on the impacting surface are modified by varying the dimensionless ratio of the orthogonal shear to the compression and extension flow rate. Simulations show varying this parameter changes the number of particle contacts governing solidification. To demonstrate this strategy in an untethered context, we show the sinking speed of a cylinder dropped onto the suspension varies markedly by changing this dimensionless ratio. These results suggest applying orthogonal shear while people are running on cornstarch would de-solidify the suspension and cause them to sink.
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Emerging 3D printing technologies offer an exciting opportunity to create customized 3D objects additively from a digital design file. 3D printing may be further leveraged for personalized medicine, clinical trial, and controlled release applications. A wide variety of 3D printing methods exists, and many studies focus on extrusion-based 3D printing techniques that closely resemble hot melt extrusion. In this paper, we explore different pharmaceutical-grade feedstock materials for creating tablet-like dosage forms using a binder jet 3D printing method. In this method, pharmaceutical-grade powders are repeatedly spread onto a build plate, followed by inkjet printing a liquid binder to selectively bind the powders in a predetermined pattern. The physical properties of the pharmaceutical-grade powders and binders have been characterized and a molding method has been developed to select appropriate powder and binder materials for subsequent printing experiments. There was a correlation between the breaking forces of the molded and printed samples, but no clear correlation was observed for disintegration time, which was primarily controlled by the higher porosity of the printed samples. The breaking force and disintegration properties of as-printed and post-processed samples containing indomethacin as an active pharmaceutical ingredient have been measured and compared with relevant literature data.
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Indometacina , Tecnologia Farmacêutica , Formas de Dosagem , Excipientes , Impressão Tridimensional , ComprimidosRESUMO
Silicones are commonly used for lubrication of syringes, encapsulation of medical devices, and fabrication of surgical implants. While silicones are generally viewed as relatively inert to the cellular milieu, they can mediate a variety of inflammatory responses and other deleterious effects, but the mechanisms underlying the bioactivity of silicones remain unresolved. Here, we report that silicone liquids and gels have high surface stresses that can strongly resist deformation at cellular length scales. Biomedical silicones, including syringe lubricants and fillings from FDA-approved breast implants, readily adsorb matrix proteins and activate canonical rigidity sensing pathways through their surface stresses. In 3D culture models, liquid silicone droplets support robust cellular adhesion and the formation of multinucleated monocyte-derived cell masses that recapitulate phenotypic aspects of granuloma formation in the foreign body response. Together, our findings implicate surface stress as a cellular stimulant that should be considered in application of silicones for biomedical purposes.
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Materiais Biocompatíveis , Fenômenos Fisiológicos Celulares , Silicones , Materiais Biocompatíveis/química , Biomimética , Implantes de Mama , Géis , Humanos , Ligantes , Lubrificação , Transdução de Sinais , Silicones/química , Tensão SuperficialRESUMO
We systematically investigate droplet movement, coalescence, and splitting on an open hydrophobic surface. These processes are actuated by magnetic beads internalized in an oil-coated aqueous droplet using an external magnet. Results are organized into an 'operating diagram' that describes regions of droplet stable motion, breakage, and release from the magnet. The results are explained theoretically with a simple model that balances magnetic, friction, and capillary-induced drag forces and includes the effects of particle type, droplet size, surrounding oil layer, surface tension, and viscosity. Finally, we discuss the implications of the results for the design of magnet-actuated droplet systems for applications such as nucleic acid purification, immunoassay and drug delivery.
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Magnetismo/métodos , Microfluídica/métodos , Interações Hidrofóbicas e Hidrofílicas , Microesferas , Modelos Teóricos , Óleos , Tamanho da Partícula , Tensão Superficial , ViscosidadeRESUMO
Background: Research in India has seldom studied caregivers’ perceptions, experiences, and needs for information and personal support after an autism spectrum disorder (ASD) diagnosis. Objectives: The objectives of the study were to understand the perceived barriers for obtaining a diagnosis and the perspectives and experiences of parents of children with autism. Materials and Methods: Parents with a diagnosed ASD child (within a year of diagnosis) in the 3–8 years range were recruited from the Pediatric Psychology and Neurodevelopmental Clinic from a tertiary care teaching hospital in North India. An interview guide elicited information about experiences regarding obtaining an ASD diagnosis, perceived barriers and facilitators, reactions to diagnosis, postdiagnostic family and community experiences, and stress experienced by parents. Qualitative responses were analyzed using thematic analysis. Participants were recruited till there was a saturation of themes. The ethics clearance was provided by the institutional review board. Results: Twenty-eight caregivers of children with ASD were recruited for the study. Overall, nine themes were identified from the qualitative analysis of the interviews: two before diagnosis (delayed help?seeking and experiences with healthcare), one at the time of diagnosis disclosure (heightened emotional response to diagnosis), and six themes after the diagnosis (increased stress, behavioral challenges, deterioration in family relationships, negative attitudes of the family, seeking support, and moving forward with hope for the future). Conclusions: There are several barriers and gaps in the autism-related available services in the country, and there is a need to provide inclusive, supportive, culturally sensitive, and family-centered model of care for parents raising children with ASD.