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1.
J Forensic Sci ; 67(3): 955-963, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35118646

RESUMO

Blood-contaminated fingermarks are significant evidence for forensic investigators in high-profile cases providing a direct link between the suspect and the crime. Although these marks are often visible, blood enhancement techniques are operationally used to recover maximal ridge detail. The standard protein dye-staining procedure includes a chemical blood-fixing step, which requires an initial, prolonged drying period, for natural coagulation to occur. However, in special cases, when it is crucial to detect forensic traces quickly, there is a need to speed up the enhancement process. This study explored, both theoretically and empirically, the use of heat as an alternative method to the standard chemical fixing. Three consecutive experiments were conducted in which blood-contaminated fingerprints were deposited on different types of surfaces (car parts, glass, and flooring tiles), and heated for different periods, prior to development by amido black solution. The results showed that heat was successful in fixing blood, while the required temperature and heating durations, were inversely proportional. This observation was in correlation with theoretical heat-transfer data, calculated by the Lumped Heat Capacity model, also demonstrating the impact of the thermal time constant of each surface, on the conditions required for the full fixing of blood. The experimental findings led to a design of a portable, and tailor-made heating device, examined for the use in crime scenes, allowing to shorten the necessary fixing process from hours to minutes. For future crime-scene work, this novel approach may be utilized for a rapid blood-fixing, especially in cases when the scene cannot be preserved.


Assuntos
Dermatoglifia , Temperatura Alta , Negro de Amido , Medicina Legal , Coloração e Rotulagem
2.
J Biol Eng ; 14: 18, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32617119

RESUMO

BACKGROUND: Implantation failure remains an unsolved obstacle in reproductive medicine. Previous studies have indicated that estrogen responsiveness, specifically by estrogen receptor alpha (ERα), is crucial for proper implantation. There is an utmost need for a reliable in vitro model that mimics the events in the uterine wall during the implantation process for studying the regulatory mechanisms governing the process. The current two-dimensional and hydrogel-based in vitro models provide only short-term endometrial cell culture with partial functionality. RESULTS: Endometrial biopsies showed an increase in E-cadherin expression on the typical window of implantation of fertile women, compared to negligible expression in recurrent implantation failure (RIF) patients. These clinical results indicated E-cadherin as a marker for receptivity. Three-dimensional (3D) macroporous alginate scaffolds were the base for epithelial endometrial cell-seeding and long-term culture under hormone treatment that mimicked a typical menstrual cycle. The RL95-2 epithelial cell culture in macroporous scaffolds was viable for 3 weeks and showed increased E-cadherin levels in response to estrogen. Human choriocarcinoma (JAR) spheroids were used as embryo models, seeded onto cell constructs and successfully adhered to the RL95-2 cell culture. Moreover, a second model of HEC-1A with low ERα levels, showed lower E-cadherin expression and no JAR attachment. E-cadherin expression and JAR attachment were recovered in HEC-1A cells that were transfected with ERα plasmid. CONCLUSIONS: We present a novel model that enables culturing endometrial cells on a 3D matrix for 3 weeks under hormonal treatment. It confirmed the importance of ERα function and E-cadherin for proper implantation. This platform may serve to elucidate the regulatory mechanisms controlling the implantation process, and for screening and evaluating potential novel therapeutic strategies for RIF.

3.
J Orthop Translat ; 16: 40-52, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30723680

RESUMO

BACKGROUND: Despite intensive research, regeneration of articular cartilage largely remains an unresolved medical concern as the clinically available modalities still suffer from long-term inconsistent data, relatively high failure rates and high prices of more promising approaches, such as cell therapy. In the present study, we aimed to evaluate the feasibility and long-term efficacy of a bilayered injectable acellular affinity-binding alginate hydrogel in a large animal model of osteochondral defects. METHODS: The affinity-binding alginate hydrogel is designed for presentation and slow release of chondrogenic and osteogenic inducers (transforming growth factor-ß1 and bone morphogenic protein 4, respectively) in two distinct and separate hydrogel layers. The hydrogel was injected into the osteochondral defects created in the femoral medial condyle in mini-pigs, and various outcomes were evaluated after 6 months. RESULTS: Macroscopical and histological assessment of the defects treated with growth factor affinity-bound hydrogel showed effective reconstruction of articular cartilage layer, with major features of hyaline tissue, such as a glossy surface and cellular organisation, associated with marked deposition of proteoglycans and type II collagen. Microcomputed tomography showed incomplete bone formation in both treatment groups, which was nevertheless augmented by the presence of affinity-bound growth factors. Importantly, the physical nature of the applied hydrogel ensured its shear resistance, seamless integration and topographical matching to the surroundings and opposing articulating surface. CONCLUSIONS: The treatment with acellular injectable growth factor-loaded affinity-binding alginate hydrogel resulted in effective tissue restoration with major hallmarks of hyaline cartilage, shown in large animal model after 6-month follow-up. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: This proof-of-concept study in a clinically relevant large animal model showed promising potential of an injectable acellular growth factor-loaded affinity-binding alginate hydrogel for effective repair and regeneration of articular hyaline cartilage, representing a strong candidate for future clinical development.

4.
PLoS One ; 11(9): e0162502, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27622508

RESUMO

OBJECTIVE: Ezrin and p130Cas are structural proteins with an important role in signaling pathways and have been shown to promote cancer dissemination. We previously reported on overexpression of both ezrin and p130Cas in breast carcinoma effusions compared to primary carcinomas. Since ovarian and breast carcinomas share the ability to disseminate by forming malignant effusions, we sought to study the role of these molecules in ovarian carcinoma (OC). METHODS: OC cell lines were cultured in two different 3-dimensional conditions, on alginate scaffolds and as spheroids, which served as models for solid tumor and malignant effusions, respectively. shRNA was used to reduce protein expression in the cells. The malignant potential was evaluated by chemo-invasion assay, branching capacity on Matrigel and rate of proliferation. Subsequently, clinical specimens of high-grade serous carcinoma effusions, ovarian tumors and solid metastases were analyzed for ezrin and p130Cas expression. RESULTS: Higher ezrin expression was found in cells composing the spheroids compared to their counterparts cultured on alginate scaffold and in clinical samples of malignant effusions compared to solid tumors. In addition, reduced Ezrin expression impaired the invasion ability and the branching capacity of OC cells to a greater extent than reduced p130Cas expression. However, ezrin and p130Cas expression in effusions was unrelated to clinical outcome. CONCLUSIONS: The 3-dimensional cell cultures were found to mimic the different tumor sites and be applicable as a model. The in vitro results concur with the clinical specimen analysis, suggesting that in OC, the role of ezrin in disease progression is more pronounced than that of p130Cas.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Neoplasias Ovarianas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Líquido Ascítico/metabolismo , Líquido Ascítico/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proteína Substrato Associada a Crk/antagonistas & inibidores , Proteína Substrato Associada a Crk/genética , Proteína Substrato Associada a Crk/metabolismo , Cistadenocarcinoma Seroso/genética , Cistadenocarcinoma Seroso/metabolismo , Cistadenocarcinoma Seroso/patologia , Proteínas do Citoesqueleto/antagonistas & inibidores , Proteínas do Citoesqueleto/genética , Progressão da Doença , Feminino , Expressão Gênica , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Derrame Pleural Maligno/genética , Derrame Pleural Maligno/metabolismo , Derrame Pleural Maligno/patologia , RNA Interferente Pequeno/genética , Esferoides Celulares
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