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1.
Biofabrication ; 16(4)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38866003

RESUMO

Tumor-on-chips (ToCs) are useful platforms for studying the physiology of tumors and evaluating the efficacy and toxicity of anti-cancer drugs. However, the design and fabrication of a ToC system is not a trivial venture. We introduce a user-friendly, flexible, 3D-printed microfluidic device that can be used to culture cancer cells or cancer-derived spheroids embedded in hydrogels under well-controlled environments. The system consists of two lateral flow compartments (left and right sides), each with two inlets and two outlets to deliver cell culture media as continuous liquid streams. The central compartment was designed to host a hydrogel in which cells and microtissues can be confined and cultured. We performed tracer experiments with colored inks and 40 kDa fluorescein isothiocyanate dextran to characterize the transport/mixing performances of the system. We also cultured homotypic (MCF7) and heterotypic (MCF7-BJ) spheroids embedded in gelatin methacryloyl hydrogels to illustrate the use of this microfluidic device in sustaining long-term micro-tissue culture experiments. We further demonstrated the use of this platform in anticancer drug testing by continuous perfusion of doxorubicin, a commonly used anti-cancer drug for breast cancer. In these experiments, we evaluated drug transport, viability, glucose consumption, cell death (apoptosis), and cytotoxicity. In summary, we introduce a robust and friendly ToC system capable of recapitulating relevant aspects of the tumor microenvironment for the study of cancer physiology, anti-cancer drug transport, efficacy, and safety. We anticipate that this flexible 3D-printed microfluidic device may facilitate cancer research and the development and screening of strategies for personalized medicine.


Assuntos
Antineoplásicos , Neoplasias da Mama , Impressão Tridimensional , Esferoides Celulares , Humanos , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/patologia , Esferoides Celulares/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Feminino , Células MCF-7 , Hidrogéis/química , Dispositivos Lab-On-A-Chip , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Dextranos/química , Gelatina/química , Doxorrubicina/farmacologia , Doxorrubicina/química , Sobrevivência Celular/efeitos dos fármacos , Metacrilatos
2.
Medicina (B.Aires) ; 84(supl.1): 2-8, mayo 2024. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1558476

RESUMO

Resumen La aparición de convulsiones es frecuente durante el periodo neonatal debido a las características de inma durez funcional del cerebro es este periodo. La aparición de estas convulsiones puede llevar a un diagnóstico de epilepsia neonatal, que suele estar asociado a alteracio nes estructurales del cerebro durante el neurodesarrollo. Aproximadamente el 50% de las personas con epilepsia activa padecen al menos un trastorno médico comórbi do, y esto hace que cambie la evolución de la epilepsia. La presencia de trastornos neurológicos que preceden a la aparición de la epilepsia indica que alteraciones es tructurales y/o funcionales del cerebro subyacentes pue den ser causa de la predisposición a padecer epilepsia y de los procesos comórbidos de manera independiente. En esta revisión describimos los procesos cerebrales estructurales y funcionales que subyacen a la aparición de epilepsia neonatal y sus comorbilidades.


Abstract The occurrence of seizures is frequent during the neonatal period due to the functional immaturity of the brain.The presence of these seizures may lead to a diagnosis of neonatal epilepsy, which is usually as sociated with structural alterations of the brain during neurodevelopment. Approximately 50% of people with active epilepsy have at least one comorbid medical di sorder, and the existence of a comorbid process changes the course of the epilepsy. The presence of neurologic disorders preceding the onset of epilepsy indicates that underlying neurobiological alterations may indepen dently cause the predisposition to epilepsy and comor bid processes. In this review we describe the structural and functional brain processes underlying the onset of neonatal epilepsy and its comorbidities.

3.
Rev. ADM ; 81(2): 77-82, mar.-abr. 2024. tab
Artigo em Espanhol | LILACS | ID: biblio-1561556

RESUMO

Introducción: la disfagia es la alteración en los mecanismos de la deglución que coexiste con múltiples enfermedades y condiciones. El conocimiento amplio de esta alteración generará mejores diagnósticos y tratamientos para el mejoramiento de la calidad de vida de estos pacientes. Aunque esta alteración podría ser del dominio común por especialistas en el área de la salud, principalmente la oral, no existe información reciente del nivel de conocimiento sobre la disfagia en el personal odontológico. Objetivo: determinar el nivel de conocimiento sobre la disfagia en un grupo de profesionales de la salud oral de Ciudad Juárez, Chihuahua. Material y método: se realizó un estudio trasversal descriptivo en un grupo de 241 odontólogos (pasantes de servicio social, odontólogos generales, periodoncistas, endodoncistas, rehabilitadores, odontopediatras y ortodoncistas) a través de una encuesta, los reactivos utilizados fueron sobre conocimiento de la disfagia, métodos de diagnóstico, signos y síntomas, tratamiento y complicaciones. Resultados: la mitad de la población encuestada refirió conocer los trastornos de la deglución (64.7%). Contrastantemente, al utilizar el término «disfagia¼, la postura del conocimiento disminuyó considerablemente (40.7%). Finalmente, los valores más bajos de la encuesta se mostraron en la falta de conocimiento sobre identificación de signos y síntomas de la disfagia (36.1%), métodos de diagnóstico (20.7%), tratamientos (18.7%) y complicaciones (23.2%). Conclusión: existe un bajo conocimiento de los trastornos de la deglución autopercibido por los profesionales de la odontología, lo que sugiere la búsqueda de los factores que ocasionan la falta del conocimiento de los profesionales del área odontológica (AU)


Introduction: dysphagia is the alteration in swallowing mechanisms that coexists with multiple diseases and conditions. The broad knowledge of this alteration will generate better diagnoses and treatments for the improvement of the quality of life of these patients. Although this alteration could be common domain by specialists in the area of health, mainly oral, there is no recent information on the level of knowledge about dysphagia in dental personnel. Objective: to determine the level of knowledge about dysphagia in a group of oral health professionals from Ciudad Juárez, Chihuahua. Material and methods: a descriptive cross-sectional study was carried out in a group of 241 dentists (social service intern, general dentists, periodontists, endodontists, rehabilitators, pediatric dentists and orthodontists) through a survey, the reagents used were on knowledge of dysphagia, diagnostic methods, signs and symptoms, treatment and complications. Results: half of the surveyed population reported knowing swallowing disorders (64.7%). In contrast, when using the term «dysphagia¼ the posture of knowledge decreased considerably (40.7%). Finally, the lowest values in the survey were found in the lack of knowledge about identification of signs and symptoms of dysphagia (36.1%), diagnostic methods (20.7%), treatments (18.7%) and complications (23.2%). Conclusion: there is a low knowledge of self-perceived swallowing disorders by dentists, which suggests the search for the factors that cause the lack of knowledge of dental professionals (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/terapia , Odontólogos/educação , Sinais e Sintomas , Epidemiologia Descritiva , Estudos Transversais , México/epidemiologia
4.
Medicina (B Aires) ; 84 Suppl 1: 2-8, 2024 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-38350617

RESUMO

The occurrence of seizures is frequent during the neonatal period due to the functional immaturity of the brain.The presence of these seizures may lead to a diagnosis of neonatal epilepsy, which is usually associated with structural alterations of the brain during neurodevelopment. Approximately 50% of people with active epilepsy have at least one comorbid medical disorder, and the existence of a comorbid process changes the course of the epilepsy. The presence of neurologic disorders preceding the onset of epilepsy indicates that underlying neurobiological alterations may independently cause the predisposition to epilepsy and comorbid processes. In this review we describe the structural and functional brain processes underlying the onset of neonatal epilepsy and its comorbidities.


La aparición de convulsiones es frecuente durante el periodo neonatal debido a las características de inmadurez funcional del cerebro es este periodo. La aparición de estas convulsiones puede llevar a un diagnóstico de epilepsia neonatal, que suele estar asociado a alteraciones estructurales del cerebro durante el neurodesarrollo. Aproximadamente el 50% de las personas con epilepsia activa padecen al menos un trastorno médico comórbido, y esto hace que cambie la evolución de la epilepsia. La presencia de trastornos neurológicos que preceden a la aparición de la epilepsia indica que alteraciones estructurales y/o funcionales del cerebro subyacentes pueden ser causa de la predisposición a padecer epilepsia y de los procesos comórbidos de manera independiente. En esta revisión describimos los procesos cerebrales estructurales y funcionales que subyacen a la aparición de epilepsia neonatal y sus comorbilidades.


Assuntos
Epilepsia , Recém-Nascido , Humanos , Epilepsia/diagnóstico , Convulsões/etiologia , Encéfalo , Comorbidade
5.
Rev. ADM ; 80(3): 139-144, mayo-jun. 2023. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1517826

RESUMO

Introducción: la Candida albicans (C. albicans) es un patógeno fúngico que puede causar infecciones superficiales o potencialmente mortales. Los biofilms de C. albicans muestran rasgos fenotípicos únicos, el más destacado es su notable resistencia a una amplia variedad de agentes antimicóticos. Una de las alternativas para inhibir el crecimiento de este microorganismo es el ozono debido a sus propiedades bactericidas, fungicidas y virucidas; sin embargo, escasa información ha sido reportada en C. albicans. Objetivo: el objetivo de este estudio fue evaluar el efecto fungicida del ozono en C. albicans. Material y métodos: la metodología consistió en agregar ozono a tubos de ensayo con medios de caldo nutritivo en diversas concentraciones y tiempos de ozonización. El efecto fungicida fue determinado con la determinación del número de colonias de C. albicans en agar nutritivo a través de procedimiento microbiológicos estandarizados por triplicado. Resultados: todas las muestras con ozono mostraron adecuados niveles de inhibición de crecimiento del microorganismo. Además, el efecto fungicida del ozono se encontró para ser significativamente dependiente del tiempo de ozonización y de la concentración. Conclusión: el uso de terapia con ozono podría tener potencial en el control de infecciones micóticas causadas por la presencia de C. albicans (AU)


Introduction: Candida albicans (C. albicans) is a fungal pathogen that can cause superficial or life-threatening infections. Biofilms of C. albicans display unique phenotypic traits, the most prominent being their remarkable resistance to a wide variety of antifungal agents. One of the alternatives to inhibit the growth of this microorganism is ozone due to its bactericidal, fungicidal and virucidal properties; however, little information has been reported on C. albicans. Objective: the objective of this study was to evaluate the fungicidal effect of ozone on C. albicans. Material and methods: the methodology consisted in adding ozone to test tubes with nutrient broth media in various concentrations and ozonation times. The fungicidal effect was determined by determining the number of colonies of C. albicans in nutrient agar through standardized microbiological procedures in triplicate. Results: all the ozone samples showed adequate levels of growth inhibition of the microorganism. Furthermore, the fungicidal effect of ozone was found to be significantly dependent on ozonation time and concentration. Conclusion: the use of ozone therapy could have potential in the control of fungal infections caused by the presence of C. albicans (AU)


Assuntos
Candida albicans/efeitos dos fármacos , Técnicas In Vitro , Contagem de Colônia Microbiana/métodos , Crescimento Bacteriano , Ozonização , Interpretação Estatística de Dados , Meios de Cultura
6.
Bioengineering (Basel) ; 10(5)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37237624

RESUMO

Tumor-on-chips have become an effective resource in cancer research. However, their widespread use remains limited due to issues related to their practicality in fabrication and use. To address some of these limitations, we introduce a 3D-printed chip, which is large enough to host ~1 cm3 of tissue and fosters well-mixed conditions in the liquid niche, while still enabling the formation of the concentration profiles that occur in real tissues due to diffusive transport. We compared the mass transport performance in its rhomboidal culture chamber when empty, when filled with GelMA/alginate hydrogel microbeads, or when occupied with a monolithic piece of hydrogel with a central channel, allowing communication between the inlet and outlet. We show that our chip filled with hydrogel microspheres in the culture chamber promotes adequate mixing and enhanced distribution of culture media. In proof-of-concept pharmacological assays, we biofabricated hydrogel microspheres containing embedded Caco2 cells, which developed into microtumors. Microtumors cultured in the device developed throughout the 10-day culture showing >75% of viability. Microtumors subjected to 5-fluorouracil treatment displayed <20% cell survival and lower VEGF-A and E-cadherin expression than untreated controls. Overall, our tumor-on-chip device proved suitable for studying cancer biology and performing drug response assays.

7.
Medicina (B.Aires) ; 83(supl.2): 2-5, abr. 2023. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1430820

RESUMO

Resumen La pandemia COVID-19 se extendió por todo por a la enorme capacidad del coronavirus SARS-CoV-2 para transmitirse entre humanos. El COVID-19 es una amenaza para la salud pública mundial. La entrada de este virus en las células se ve muy facilitada por la presencia de la enzima convertidora de angiotensina 2 (ACE2) en la membrana celular. Hoy en día no tenemos un conocimiento preciso de cómo se expresa este receptor en el cerebro durante el desarrollo humano y, como consecuencia, no sabemos si las células neurales en desarrollo son susceptibles de ser infectadas a través de la transmisión de madre a feto. Revisamos en este artículo los conocimientos sobre la expresión de ACE2 en el cerebro humano en desarrollo, con especial atención a la etapa fetal. Esta etapa corresponde al periodo de formación de la corteza cerebral. La posibilidad de infección por SARS-CoV-2 durante el periodo fetal puede alterar el desarrollo normal de la corteza cerebral. Así pues, aunque se han publicado pocos casos demostrando la transmisión vertical de la infección por SARS-CoV-2, el gran número de jóvenes infectados puede representar un problema sanitario que necesite seguimiento, por la posibilidad de que se originen alteraciones cognitivas y anomalías en el desarrollo de los circuitos corticales, que pueden representar predisposición a padecer problemas mentales a lo largo de la vida.


Abstract The COVID-19 pandemic spread around the world due to the enormous transmission of the SARS-CoV-2 among humans. COVID-19 represents a threat to global public health. The entry of this virus into cells is greatly facilitated by the presence of angiotensin-converting enzyme 2 (ACE2) in the cell membrane. Today we do not have a precise understanding of how this receptor expresses in the brain during human development and, as a consequence, we do not know whether neural cells in the developing brain are susceptible to infection. We review the knowledge about ACE2 expression in the developing human brain, with special attention to the fetal stage. This stage corresponds to the period of the cerebral cortex formation. Therefore, SARS-CoV-2 infection during the fetal period may alter the normal development of the cerebral cortex. Although few cases have been published demonstrating vertical transmission of SARS-CoV-2 infection, the large number of infected young people may represent a problem which requires health surveillance, due to the possibility of cognitive alterations and abnormalities in the development of cortical circuits that may represent a predisposition to mental problems later in life.

8.
Medicina (B Aires) ; 83 Suppl 2: 2-5, 2023 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-36820474

RESUMO

The COVID-19 pandemic spread around the world due to the enormous transmission of the SARSCoV-2 among humans. COVID-19 represents a threat to global public health. The entry of this virus into cells is greatly facilitated by the presence of angiotensin-converting enzyme 2 (ACE2) in the cell membrane. Today we do not have a precise understanding of how this receptor expresses in the brain during human development and, as a consequence, we do not know whether neural cells in the developing brain are susceptible to infection. We review the knowledge about ACE2 expression in the developing human brain, with special attention to the fetal stage. This stage corresponds to the period of the cerebral cortex formation. Therefore, SARS-CoV-2 infection during the fetal period may alter the normal development of the cerebral cortex. Although few cases have been published demonstrating vertical transmission of SARS-CoV-2 infection, the large number of infected young people may represent a problem which requires health surveillance, due to the possibility of cognitive alterations and abnormalities in the development of cortical circuits that may represent a predisposition to mental problems later in life.


La pandemia COVID-19 se extendió por todo por a la enorme capacidad del coronavirus SARS-CoV-2 para transmitirse entre humanos. El COVID-19 es una amenaza para la salud pública mundial. La entrada de este virus en las células se ve muy facilitada por la presencia de la enzima convertidora de angiotensina 2 (ACE2) en la membrana celular. Hoy en día no tenemos un conocimiento preciso de cómo se expresa este receptor en el cerebro durante el desarrollo humano y, como consecuencia, no sabemos si las células neurales en desarrollo son susceptibles de ser infectadas a través de la transmisión de madre a feto. Revisamos en este artículo los conocimientos sobre la expresión de ACE2 en el cerebro humano en desarrollo, con especial atención a la etapa fetal. Esta etapa corresponde al periodo de formación de la corteza cerebral. La posibilidad de infección por SARS-CoV-2 durante el periodo fetal puede alterar el desarrollo normal de la corteza cerebral. Así pues, aunque se han publicado pocos casos demostrando la transmisión vertical de la infección por SARS-CoV-2, el gran número de jóvenes infectados puede representar un problema sanitario que necesite seguimiento, por la posibilidad de que se originen alteraciones cognitivas y anomalías en el desarrollo de los circuitos corticales, que pueden representar predisposición a padecer problemas mentales a lo largo de la vida.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Adolescente , Enzima de Conversão de Angiotensina 2/metabolismo , Peptidil Dipeptidase A , Pandemias , Encéfalo
9.
Artigo em Inglês | MEDLINE | ID: mdl-36610635

RESUMO

Hormones are key factors in determining the response of organisms to their environment. For example, the juvenile hormone (JH) coordinates the insects' development, reproduction, and survival. However, it is still unclear how the impact of juvenile hormone on insect immunity varies depending on the sex and reproductive state of the individual, as well as the type of the immune challenge (i.e., Gram-positive or Gram-negative bacteria). We used Tenebrio molitor and methoprene, a JH analog (JHa) to explore these relationships. We tested the effect of methoprene on phenoloxidase activity (PO), an important component of humoral immunity in insects, and hemocyte number. Lyophilized Gram-positive Staphylococcus aureus or Gram-negative Escherichia coli were injected for the immune challenge. The results suggest that JH did not affect the proPO, PO activity, or hemocyte number of larvae. JH and immune challenge affected the immune response and consequently, affected adult developmental stage and sex. We propose that the influence of JH on the immune response depends on age, sex, the immune response parameter, and the immune challenge, which may explain the contrasting results about the role of JH in the insect immune response.


Assuntos
Hormônios Juvenis , Metoprene , Animais , Hormônios Juvenis/farmacologia , Monofenol Mono-Oxigenase , Hemócitos , Reprodução
10.
Rev. ADM ; 79(4)jul.-ago. 2022. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1395261

RESUMO

Introducción: el biofilm dental microbiano es el precursor de diversas enfermedades orales, una de ellas la caries, ésta representa la enferme- dad oral más significativa a nivel mundial, con una incidencia de 1.76 billones de niños afectados. Las nanopartículas de plata (AgNPs) se están usando como alternativa para el control y prevención del biofilm dental, ya que poseen propiedades antimicrobianas contra bacterias relacionadas a estas enfermedades. Sin embargo, no hay estudios que evalúen este comportamiento en pacientes pediátricos. Objetivo: eva- luar la actividad antimicrobiana de las AgNPs en bacterias de aislados clínicos tomados de pacientes pediátricos. Material y métodos: se tomó muestra del biofilm dental de 22 pacientes pediátricos, el efecto micro- biológico se evaluó mediante ensayos microbiológicos estandarizados internacionalmente por triplicado, usando dos diferentes tamaños de AgNPs. Resultados: los dos tamaños de AgNPs mostraron inhibición bacteriana, sin embargo, sólo se vio una diferencia estadísticamente significativa entre el género (p < 0.05), además, en general, hubo una correlación positiva significativa en relación a la concentración de las AgNPs y la velocidad del crecimiento bacteriano (p < 0.05). Conclusión: las AgNPs se pueden considerar como una alternativa para la prevención del biofilm dental y de esta manera para el control de diferentes enfermedades orales (AU))


Introduction: dental biofilm is the precursor of oral diseases, one of them dental caries, this represents the most significant oral disease worldwide with an incidence of 1.76 billion affected children. Silver nanoparticles (AgNPs) are being used as an alternative for the control and prevention of dental biofilm since they have antimicrobial properties against bacteria related to these diseases. However, there are no studies evaluating this behavior in pediatric patients. Objective: to evaluate the antimicrobial activity of AgNPs in bacteria from clinical isolates taken from pediatric patients. Material and methods: a sample of dental biofilm was taken from 22 pediatric patients, the microbiological effect was evaluated by international standardized microbiological tests in triplicate, using two different sizes of AgNPs. Results: the two sizes of AgNPs showed bacterial inhibition, however, only a statistically significant difference was seen between gender (p < 0.05), in addition, in general, there was a significant positive correlation in relation to the concentration of AgNPs and the speed bacterial growth (p < 0.05). Conclusion: AgNPs can be considered as an alternative for the prevention of dental biofilm and thus for the control of different oral diseases (AU)


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Cárie Dentária/prevenção & controle , Placa Dentária/prevenção & controle , Nanopartículas/uso terapêutico , Crescimento Bacteriano , Assistência Odontológica para Crianças/métodos , Meios de Cultura , Placa Dentária/microbiologia , Distribuição por Idade e Sexo
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