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1.
J Photochem Photobiol B ; 257: 112971, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38955081

RESUMO

Bovine mastitis (BM) represents a significant challenge in the dairy industry. Limitations of conventional treatments have prompted the exploration of alternative approaches, such as photodynamic inactivation (PDI). In this study, we developed a PDI protocol to eliminate BM-associated pathogens using porphyrin-doped conjugated polymer nanoparticles (CPN). The PDI-CPN protocol was evaluated in four mastitis isolates of Staphylococcus and in a hyper-biofilm-forming reference strain. The results in planktonic cultures demonstrated that PDI-CPN exhibited a bactericidal profile upon relatively low light doses (∼9.6 J/cm2). Furthermore, following a seven-hour incubation period, no evidence of cellular reactivation was observed, indicating a highly efficient post-photodynamic inactivation effect. The successful elimination of bacterial suspensions encouraged us to test the PDI-CPN protocol on mature biofilms. Treatment using moderate light dose (∼64.8 J/cm2) reduced biofilm biomass and metabolic activity by up to 74% and 88%, respectively. The impact of PDI-CPN therapy on biofilms was investigated using scanning electron microscopy (SEM), which revealed nearly complete removal of the extracellular matrix and cocci. Moreover, ex vivo studies conducted on bovine udder skin demonstrated the efficacy of the therapy in eliminating bacteria from these scaffolds and its potential as a prophylactic method. Notably, the histological analysis of skin revealed no signs of cellular degeneration, suggesting that the protocol is safe and effective for BM treatment. Overall, this study demonstrates the potential of PDI-CPN in treating and preventing BM pathogens. It also provides insights into the effects of PDI-CPN on bacterial growth, metabolism, and survival over extended periods, aiding the development of effective control strategies and the optimization of future treatments.


Assuntos
Biofilmes , Luz , Mastite Bovina , Nanopartículas , Polímeros , Animais , Bovinos , Nanopartículas/química , Mastite Bovina/microbiologia , Mastite Bovina/tratamento farmacológico , Biofilmes/efeitos dos fármacos , Biofilmes/efeitos da radiação , Feminino , Polímeros/química , Polímeros/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Porfirinas/química , Porfirinas/farmacologia , Staphylococcus/efeitos dos fármacos , Staphylococcus/efeitos da radiação , Antibacterianos/farmacologia , Antibacterianos/química , Microscopia Eletrônica de Varredura , Fotoquimioterapia
2.
Brain Sci ; 14(6)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38928527

RESUMO

Brain tumors are a significant concern for the global medical community, with over 300,000 cases reported annually worldwide [...].

3.
Molecules ; 29(11)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38893463

RESUMO

Diverse methodologies exist to determine the chemical composition, proximate analysis, and calorific value of biomass. Researchers select and apply a specific methodology according to the lignocellulosic material they study and the budgetary resources available. In this project, we determined the primary chemical constitution and proximate analysis of Prosopis laevigata (Humb. & Bonpl.) Jonhst wood using a traditional chemical method and a novel procedure based on the deconvolution of the DTG signal produced by TGA. The highest calorific value was verified using a calorimetric pump based on mathematical models. We also conducted elemental analysis and a microanalysis of ash, and applied Fourier transform infrared spectroscopic analysis (FT-IR). The means of the results obtained by the chemical method and TGA-DTG, respectively, were: hemicelluloses 7.36%-(8.72%), cellulose 48.28%-(46.08%), lignin 30.57%-(32.44%), extractables 13.53%-(12.72%), moisture 2.03%-(4.96%), ash 1.77%-(1.90%), volatile matter 75.16%-(74.14%), and fixed carbon 23.05%-(18.93%). The procedure with the calorimetric pump generated a calorific value above 20.16 MJ/kg. The range generated by the various models was 18.23-21.07 MJ/kg. The results of the elemental analysis were: carbon 46.4%, hydrogen 6.79%, oxygen 46.43%, nitrogen 0.3%, and sulfur 0.5%. The microanalysis of ash identified 18 elements. The most abundant ones were potassium ˃ calcium ˃ sodium. Based on the infrared spectrum (FT-IR) of Prosopis laevigata wood, we detected the following functional groups: OH, C-H, C=O, CH2, CH3, C-O-C, C-OH, and C4-OH. Our conclusion is that the TGA-DTG method made it possible to obtain results in less time with no need for the numerous reagents that chemical procedures require. The calorific value of P. laevigata wood is higher than the standards. Finally, according to our results, proximate analysis provides the best model for calculating calorific value.


Assuntos
Lignina , Prosopis , Termogravimetria , Madeira , Madeira/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Prosopis/química , Lignina/química , Lignina/análise , Biomassa , Celulose/química , Celulose/análise , Polissacarídeos
4.
PLoS One ; 18(12): e0295506, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38128051

RESUMO

The aim of the study was to describe and analyze the experience of people with advanced chronic kidney disease. Chronic kidney disease is a growing public health problem that is on the increase worldwideThe experience of living with this illness is paradoxical, as it can include feelings of dependent autonomy, distant connection, abnormal normalcy, and uncertain hope. Every chronic disease involves a biographical alteration from the onset. For those who suffer it, it implies a breaking down and reconstruction of their everyday life. Despite the prevalence of the disease and the increase in the number of qualitative research studies in recent decades, there has not been much research on the experience of people with Chronic kidney disease. This is a qualitative study that began in 2018 and concluded in 2021.Twenty-one people with advanced chronic kidney disease were interviewed. They participated voluntarily with informed consent Participants were selected by purposive sampling. Data analysis was guided by grounded theory procedures using the Nvivo 12 software. This study reveals that people with advanced chronic kidney disease do not feel the same as they used to because their control over their lives is limited; because they feel their health is in a continuous state of deterioration; and because of the changes in themselves and in their relationships with others. With chronic kidney disease, their identity is continually called into question. The normal lives of these people-their biographical constructions-are precarious and are continuously being remodelled by the effects of treatment and the inexorable course of this disease. This study contributes to an understanding of the experience of people with advanced chronic kidney disease. It can contribute to helping health care professionals effectively support these patients in their efforts to lead a normal life and in making decisions about their treatment.


Assuntos
Insuficiência Renal Crônica , Humanos , Doença Crônica , Pesquisa Qualitativa , Tomada de Decisões , Pessoal de Saúde
5.
Medicina (B.Aires) ; 83(supl.4): 95-101, oct. 2023. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1521209

RESUMO

Resumen Introducción : La trombosis de venas y senos venosos cerebrales (TVSC) constituye una causa conocida, aun que subestimada de ictus en la infancia. Su diagnóstico requiere un alto índice de sospecha, una correcta in terpretación de la neuroimagen e interrelación entre el clínico y el radiólogo. Objetivo : Analizar las manifestaciones clínicas, fac tores de riesgo y neuroimagen de recién nacidos (RN) y niños menores de 15 años con TVSC. Métodos: Estudio descriptivo, retrospectivo, multi céntrico, de una serie consecutiva de casos de menores de 15 años que ingresaron por TVSC entre el 1 de enero del 2010 y el 1 de marzo de 2022. Resultados : El estudio incluyó 51 pacientes: 39% con síntomas agudos y 59% subagudos. En los RN predomi naron síntomas encefalopáticos y convulsiones, mien tras en los niños elementos de hipertensión endocranea na (HTEC). Se identificaron factores de riesgo en el 90% de los casos. La resonancia magnética con angiografía en tiempo venoso confirmó el diagnóstico en el 80%, siendo el seno recto el más afectado en RN y el seno lateral en niños. Se encontraron complicaciones hemorrágicas en 30.5%, siendo más frecuentes en los RN. Se inició anti coagulación en el 82% sin complicaciones. Las secuelas estuvieron presentes en 44.4% de RN y 37.9% de niños, siendo más frecuentes y graves en los RN. Conclusiones : Para realizar un diagnóstico precoz es fundamental pensar en TVSC en RN con síntomas en cefalopáticos y/o convulsiones y en mayores con clínica de HTEC en presencia de enfermedades predisponentes o desencadenantes.


Abstract Introduction : Cerebral venous sinus thrombosis (CVST) is a well-known, although underestimated, cause of stroke in childhood. Its diagnosis requires a high index of suspicion, a correct interpretation of neuroim aging studies and an interrelation between clinicians and radiologists. The clinical features, risk factors and neuroimaging of children under 15 years of age with CVST were analyzed. Methods : multicenter, retrospective, descriptive, study of a consecutive series of cases of children under 15 years of age, who were admitted due to CVST between January 1st, 2010, and March 1st, 2022. Results : The study included 51 patients: 39% with acute symptoms and 59% with subacute symptoms. Newborns predominantly presented encephalopathic symptoms and seizures, while children exhibited signs of intracranial hypertension (ICH). Risk factors were 96 identified in 90% of the cases. Magnetic resonance with angiography in venous time confirmed the diagnosis in 80% of the patients, with the straight sinus being the most affected in newborns and the lateral sinus in chil dren. Hemorrhagic complications were found in 30.5%, being more frequent in newborns. Anticoagulation was initiated in 82% without complications. Sequelae were present in 44.4% of newborns and 37.9% of children, being more frequent and severe in newborns. Conclusions : To make an early diagnosis, it is essen tial to consider CVST in newborns with encephalopathic symptoms and/or seizures, and in children with signs of ICH in the presence of predisposing or triggering conditions.

6.
Medicina (B Aires) ; 83 Suppl 4: 95-101, 2023 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-37714130

RESUMO

INTRODUCTION: Cerebral venous sinus thrombosis (CVST) is a well-known, although underestimated, cause of stroke in childhood. Its diagnosis requires a high index of suspicion, a correct interpretation of neuroimaging studies and an interrelation between clinicians and radiologists. The clinical features, risk factors and neuroimaging of children under 15 years of age with CVST were analyzed. METHODS: multicenter, retrospective, descriptive, study of a consecutive series of cases of children under 15 years of age, who were admitted due to CVST between January 1st, 2010, and March 1st, 2022. RESULTS: The study included 51 patients: 39% with acute symptoms and 59% with subacute symptoms. Newborns predominantly presented encephalopathic symptoms and seizures, while children exhibited signs of intracranial hypertension (ICH). Risk factors were identified in 90% of the cases. Magnetic resonance with angiography in venous time confirmed the diagnosis in 80% of the patients, with the straight sinus being the most affected in newborns and the lateral sinus in children. Hemorrhagic complications were found in 30.5%, being more frequent in newborns. Anticoagulation was initiated in 82% without complications. Sequelae were present in 44.4% of newborns and 37.9% of children, being more frequent and severe in newborns. CONCLUSIONS: To make an early diagnosis, it is essential to consider CVST in newborns with encephalopathic symptoms and/or seizures, and in children with signs of ICH in the presence of predisposing or triggering conditions.


Introducción: La trombosis de venas y senos venosos cerebrales (TVSC) constituye una causa conocida, aunque subestimada de ictus en la infancia. Su diagnóstico requiere un alto índice de sospecha, una correcta interpretación de la neuroimagen e interrelación entre el clínico y el radiólogo. OBJETIVO: Analizar las manifestaciones clínicas, factores de riesgo y neuroimagen de recién nacidos (RN) y niños menores de 15 años con TVSC. Métodos: Estudio descriptivo, retrospectivo, multicéntrico, de una serie consecutiva de casos de menores de 15 años que ingresaron por TVSC entre el 1 de enero del 2010 y el 1 de marzo de 2022. RESULTADOS: El estudio incluyó 51 pacientes: 39% con síntomas agudos y 59% subagudos. En los RN predominaron síntomas encefalopáticos y convulsiones, mientras en los niños elementos de hipertensión endocraneana (HTEC). Se identificaron factores de riesgo en el 90% de los casos. La resonancia magnética con angiografía en tiempo venoso confirmó el diagnóstico en el 80%, siendo el seno recto el más afectado en RN y el seno lateral en niños. Se encontraron complicaciones hemorrágicas en 30.5%, siendo más frecuentes en los RN. Se inició anticoagulación en el 82% sin complicaciones. Las secuelas estuvieron presentes en 44.4% de RN y 37.9% de niños, siendo más frecuentes y graves en los RN. CONCLUSIONES: Para realizar un diagnóstico precoz es fundamental pensar en TVSC en RN con síntomas encefalopáticos y/o convulsiones y en mayores con clínica de HTEC en presencia de enfermedades predisponentes o desencadenantes.


Assuntos
Encefalopatias , Trombose dos Seios Intracranianos , Recém-Nascido , Humanos , Criança , Estudos Retrospectivos , Trombose dos Seios Intracranianos/diagnóstico por imagem , Trombose dos Seios Intracranianos/etiologia , Convulsões/etiologia , Angiografia
7.
Cells ; 12(11)2023 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-37296661

RESUMO

Alternative therapies such as photodynamic therapy (PDT) that combine light, oxygen and photosensitizers (PSs) have been proposed for glioblastoma (GBM) management to overcome conventional treatment issues. An important disadvantage of PDT using a high light irradiance (fluence rate) (cPDT) is the abrupt oxygen consumption that leads to resistance to the treatment. PDT metronomic regimens (mPDT) involving administering light at a low irradiation intensity over a relatively long period of time could be an alternative to circumvent the limitations of conventional PDT protocols. The main objective of the present work was to compare the effectiveness of PDT with an advanced PS based on conjugated polymer nanoparticles (CPN) developed by our group in two irradiation modalities: cPDT and mPDT. The in vitro evaluation was carried out based on cell viability, the impact on the macrophage population of the tumor microenvironment in co-culture conditions and the modulation of HIF-1α as an indirect indicator of oxygen consumption. mPDT regimens with CPNs resulted in more effective cell death, a lower activation of molecular pathways of therapeutic resistance and macrophage polarization towards an antitumoral phenotype. Additionally, mPDT was tested in a GBM heterotopic mouse model, confirming its good performance with promising tumor growth inhibition and apoptotic cell death induction.


Assuntos
Glioblastoma , Nanopartículas , Fotoquimioterapia , Camundongos , Animais , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Fotoquimioterapia/métodos , Polímeros , Microambiente Tumoral , Linhagem Celular Tumoral
8.
Brain Sci ; 13(4)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37190507

RESUMO

Gliomas are primary malignant brain tumors. These tumors seem to be more and more frequent, not only because of a true increase in their incidence, but also due to the increase in life expectancy of the general population. Among gliomas, malignant gliomas and more specifically glioblastomas (GBM) are a challenge in their diagnosis and treatment. There are few effective therapies for these tumors, and patients with GBM fare poorly, even after aggressive surgery, chemotherapy, and radiation. Over the last decade, it is now appreciated that these tumors are composed of numerous distinct tumoral and non-tumoral cell populations, which could each influence the overall tumor biology and response to therapies. Monocytes have been proved to actively participate in tumor growth, giving rise to the support of tumor-associated macrophages (TAMs). In GBM, TAMs represent up to one half of the tumor mass cells, including both infiltrating macrophages and resident brain microglia. Infiltrating macrophages/monocytes constituted ~ 85% of the total TAM population, they have immune functions, and they can release a wide array of growth factors and cytokines in response to those factors produced by tumor and non-tumor cells from the tumor microenvironment (TME). A brief review of the literature shows that this cell population has been increasingly studied in GBM TME to understand its role in tumor progression and therapeutic resistance. Through the knowledge of its biology and protumoral function, the development of therapeutic strategies that employ their recruitment as well as the modulation of their immunological phenotype, and even the eradication of the cell population, can be harnessed for therapeutic benefit. This revision aims to summarize GBM TME and localization in tumor niches with special focus on TAM population, its origin and functions in tumor progression and resistance to conventional and experimental GBM treatments. Moreover, recent advances on the development of TAM cell targeting and new cellular therapeutic strategies based on monocyte/macrophages recruitment to eradicate GBM are discussed as complementary therapeutics.

9.
Biomater Adv ; 149: 213399, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37011423

RESUMO

In recent years significant efforts have been made to develop new materials for wound dressing with improved healing properties. However, the synthesis methods usually employed to this end are often complex or require several steps. We describe here the synthesis and characterization of antimicrobial reusable dermatological wound dressings based on N-isopropylacrylamide co-polymerized with [2-(Methacryloyloxy) ethyl] trimethylammonium chloride hydrogels (NIPAM-co-METAC). The dressings were obtained with a very efficient single-step synthesis procedure based on visible light (455 nm) by photopolymerization. To this end, F8BT nanoparticles of the conjugated polymer (poly(9,9-dioctylfluorene-alt-benzothiadiazole) - F8BT) were used as macro-photoinitiators, and a modified silsesquioxane was employed as crosslinker. Dressings obtained by this simple and gentle method show antimicrobial and wound healing properties, without the incorporation of antibiotics or any other additives. The physical and mechanical properties of these hydrogel-based dressings were evaluated, as well as their microbiological properties, through in vitro experiments. Results show that dressings with a molar ratio of METAC of 0.5 or higher exhibit high swelling capacity, appropriate water vapor transmission rate values, stability and thermal response, high ductility and adhesiveness. In addition, biological tests showed that the dressings have significant antimicrobial capacity. The best inactivation performance was found for hydrogels synthesized with the highest METAC content. The dressings were tested several times with fresh bacterial cultures, showing a bacterial kill efficiency of 99.99 % even after three repetitions in a row, employing the same dressing, demonstrating the intrinsic bactericidal property of the materials and their reusability. In addition, the gels show low hemolytic effect, high dermal biocompatibility and noticeable wound healing effects. Overall results demonstrate that some specific hydrogel formulations have potential application as dermatological dressings for wound healing and disinfection.


Assuntos
Antibacterianos , Anti-Infecciosos , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Cicatrização , Bandagens , Hidrogéis/farmacologia
10.
Int J Pharm ; 630: 122435, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36442723

RESUMO

"Smart" nanogels are an attractive tool for the development of new strategies of immunization in veterinary medicine. Here, we reported the synthesis and physicochemical characterization of thermoresponsive nanogels based on poly(N-isopropylacrylamide) (pNIPAM) and theirin vitro, ex vivoand in vivo (mice model) performance. Smart nanogels of ca. 250 nm, with a transition temperature of 32 °C were obtained by precipitation polymerization. Assays to evaluatepNIPAM nanogels cytotoxicity were performed in different cell lines showing high biocompatibility (>70 %). The efficient internalization of the system was studied by confocal microscopy as well as flow cytometry. The ability to protect and deliver antigens was analyzed using the outer membrane lipoprotein A (OmlA), an important virulence factor ofActinobacillus pleuropneumoniae(App)cause of porcine pleuropneumonia. This lipoprotein was synthesized by recombinant technology and its technique was also described. The biodistribution ofpNIPAM nanogels administered intranasally was performedinvivo and ex vivo through Pearl Imaging System, which showed that nanogels were kept mostly in the lungs during the evaluated time. Besides, the efficacy of the proposal nanogel-based vaccine was studiedin vivoby measuring the antibody titers of BALB/c mice inoculated with OmlA encapsulated intopNIPAM nanogels compared to OmlA plus aluminum hydroxide adjuvant. The results proved the ability of nanogels to stimulate a humoral immune response. Therefore, we have demonstrated thatpNIPAM nanogels can be used as an efficient platform for vaccine nanocarriers.


Assuntos
Resinas Acrílicas , Vacinas , Camundongos , Suínos , Animais , Nanogéis , Distribuição Tecidual , Resinas Acrílicas/química
11.
Rev. colomb. med. fis. rehabil. (En línea) ; 33(suplemento): 237-248, 2023.
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1531872

RESUMO

En Puerto Rico, la especialidad de medicina física y rehabilitación surgió en la década de los años cincuenta y a partir de ese momento ha progresado gracias a la creación de programas de adiestramiento de vanguardia, el establecimiento de una cultura de investigación científica y el desarrollo de la especialidad primaria y de subespecialidades como manejo de dolor, medicina del deporte, rehabilitación pediátrica, medicina neuromuscular, medicina de trauma cerebral y medicina de lesiones medulares. La práctica clínica más común es la de atención a pacientes externos con dolor, lesiones musculoesqueléticas y daños en el sistema nervioso, pero se ha presentado un aumento en los servicios de rehabilitación intensiva de pacientes que requieren hospitalización; en el uso de técnicas intervencionistas para manejo de dolor, lesiones de tejido blando y articulares, así como en el manejo de espasticidad. Actualmente, la especialidad de fisiatría en Puerto Rico enfrenta grandes retos, como lo son el control de las aseguradoras sobre los servicios que se les ofrecen a pacientes con impedimentos físicos y restricciones de participación, el incremento en la cantidad de documentos requeridos para que se aprueben estos servicios y la competencia de otros profesionales de la salud que han incursionado en el campo de rehabilitación. Las oportunidades para la especialidad incluyen el aumento de la población mayor y con discapacidad que requiere servicios de rehabilitación; el desarrollo de las prácticas de subespecialidad, y la necesidad de aumentar la evidencia científica que demuestre la efectividad de los tratamientos que se ofrecen y de apoyar las políticas públicas que aumenten el acceso a servicios de rehabilitación para personas de escasos recursos.


In Puerto Rico, the specialty in physical medicine and rehabilitation emerged in the 1950s and since then it has progressed thanks of the creation of cuttingedge training programs, the establishment of a culture of scientific research and the development of the primary specialty and subspecialties such as pain management, sports medicine, pediatric rehabilitation, neuromuscular medicine, brain trauma medicine, and spinal cord injury medicine. The most common clinical practice is the care of outpatients with pain, musculoskeletal injuries and damage of the nervous system, but there has been an increase in intensive rehabilitation services for patients who require hospitalization, in the use of interventionist techniques for the management of pain, soft tissue and joint injuries, as well as for the management of spasticity. Currently, the specialty of physiatry in Puerto Rico faces big challenges, such as the control of the insurers on the services offered to patients with physical impairments and participation restrictions, the increase in the number of documents required for the approval of these services, and the competition of other health care professionals who have ventured into the field of rehabilitation. The opportunities for the specialty include the increase in the elderly and disabled population requiring rehabilitation services, the development of subspecialty practices, and the need to increase scientific evidence that demonstrates the effectiveness of the treatments offered and to support public policies that increase the access to rehabilitation services for people with limited resources.


Assuntos
Humanos , Porto Rico , Pesquisa
12.
J Photochem Photobiol B ; 234: 112510, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36049287

RESUMO

Each year a rising number of infections can not be successfully treated owing to the increasing pandemic of antibiotic resistant pathogens. The global shortage of innovative antibiotics fuels the emergence and spread of drug resistant microbes. Basic research, development, and applications of alternative therapies are urgently needed. Since the 90´s, light-mediated therapies have promised to be the next frontier combating multidrug-resistance microbes. These platforms have demonstrated to be a reliable, rapid, and efficient alternative to eliminate tenacious pathogens while avoiding the emergence of resistance mechanisms. Among the materials showing antimicrobial activity triggered by light, conjugated polymers (CPs) have risen as the most promising option to tackle this complex situation. These materials present outstanding characteristics such as high absorption coefficients, great photostability, easy processability, low cytotoxicity, among others, turning them into a powerful class of photosensitizer (PS)/photothermal agent (PTA) materials. Herein, we summarize and discuss the advances in the field of CPs with applications in photodynamic inactivation and photothermal therapy towards bacteria elimination. Additionally, a section of current challenges and needs in terms of well-defined benchmark experiments and conditions to evaluate the efficiency of phototherapies is presented.


Assuntos
Fotoquimioterapia , Polímeros , Antibacterianos , Bactérias , Fármacos Fotossensibilizantes/farmacologia , Fototerapia , Polímeros/farmacologia
13.
Animals (Basel) ; 12(7)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35405827

RESUMO

In Mexico, information on goat production is scarce and documenting goat production challenges and future perspectives could be of great value, not only for Latin America, but also for international players-including those from farms, industry, and academia. Therefore, the objective of this review is to provide current knowledge on goat production systems in Mexico and discuss current challenges and future perspectives for this animal production sector. In Mexico, more than 70% of goats are produced under extensive production systems in arid and semi-arid areas and roughly 25% are produced in intensive or semi-intensive systems. Main breeds are French Alpine, Saanen, Toggenburg, LaMancha, Nubian, Boer, and their crosses. The main challenges are correlated at different levels, where economic, social, and environmental issues are mixed and are closely associated with goat health and welfare. Newly available farming technologies could be an option that should be explored. Mexican goat farming systems will need to look at the animal, social, and environmental factors to promote sustainable production systems.

14.
Int J Mol Sci ; 23(7)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35408872

RESUMO

Triple-negative breast cancer (TNBC) is an aggressive cancer with limited targeted therapies. RNA aptamers, suitably chemically modified, work for therapeutic purposes in the same way as antibodies. We recently generated 2'Fluoro-pyrimidines RNA-aptamers that act as effective recognition elements for functional surface signatures of TNBC cells. Here, we optimized three of them by shortening and proved the truncated aptamers as optimal candidates to enable active targeting to TNBC. By using prediction of secondary structure to guide truncation, we identified structural regions that account for the binding motifs of the full-length aptamers. Their chemical synthesis led to short aptamers with superb nuclease resistance, which specifically bind to TNBC target cells and rapidly internalize into acidic compartments. They interfere with the growth of TNBC cells as mammospheres, thus confirming their potential as anti-tumor agents. We propose sTN145, sTN58 and sTN29 aptamers as valuable tools for selective TNBC targeting and promising candidates for effective treatments, including therapeutic agents and targeted delivery nanovectors.


Assuntos
Antineoplásicos , Aptâmeros de Nucleotídeos , Neoplasias de Mama Triplo Negativas , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Aptâmeros de Nucleotídeos/química , Linhagem Celular Tumoral , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia
15.
Pharmaceutics ; 14(3)2022 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35336001

RESUMO

Photodynamic therapy (PDT) may be an excellent alternative in the treatment of breast cancer, mainly for the most aggressive type with limited targeted therapies such as triple-negative breast cancer (TNBC). We recently generated conjugated polymer nanoparticles (CPNs) as efficient photosensitizers for the photo-eradication of different cancer cells. With the aim of improving the selectivity of PDT with CPNs, the nanoparticle surface conjugation with unique 2'-Fluoropyrimidines-RNA-aptamers that act as effective recognition elements for functional surface signatures of TNBC cells was proposed and designed. A coupling reaction with carbodiimide was used to covalently bind NH2-modified aptamers with CPNs synthetized with two polystyrene-based polymer donors of COOH groups for the amide reaction. The selectivity of recognition for TNBC membrane receptors and PDT efficacy were assayed in TNBC cells and compared with non-TNBC cells by flow cytometry and cell viability assays. Furthermore, in vitro PDT efficacy was assayed in different TNBC cells with significant improvement results using CL4, sTN29 and sTN58 aptamers compared to unconjugated CPNs and SCR non-specific aptamer. In a chemoresistance TNBC cell model, sTN58 was the candidate for improving labelling and PDT efficacy with CPNs. We proposed sTN58, sTN29 and CL4 aptamers as valuable tools for selective TNBC targeting, cell internalization and therapeutic improvements for CPNs in PDT protocols.

17.
Saúde Soc ; 31(1): e180010, 2022.
Artigo em Espanhol | LILACS | ID: biblio-1357431

RESUMO

Resumen Este estudio pretende profundizar en la experiencia vivida por mujeres mexicanas en la emergencia obstétrica. Para ello, se realizó un estudio cualitativo-fenomenológico por medio de entrevistas en profundidad a 15 mujeres sobrevivientes de esta experiencia que se realizaron en el periodo de enero a septiembre de 2017. La información se procesó mediante análisis fenomenológico del discurso, y para su interpretación se organizó en las cuatro dimensiones de la fenomenología de la percepción: cuerpo, tiempo, espacio y relacionabilidad. Las informantes percibieron la complicación de forma temprana, sin embargo, postergaron la atención institucional hasta que se hicieron presentes signos objetivos de complicación; la llegada puntual a los servicios de salud no implicó, desde su percepción, la certeza de manejo oportuno y adecuado, además se reportó un insuficiente apoyo de las redes formales e informales para el traslado y la atención especializada. Es necesario que sociedad y gobierno articulen estrategias que empoderen a las mujeres para la atención a las situaciones de emergencia obstétrica, acciones que promuevan su autocuidado pero garanticen también el apoyo pronto y expedito de sus redes y una atención profesional de calidad.


Abstract This article aims to explore the experience of Mexican women in the obstetric emergency. This qualitative-phenomenological study was conducted with data collected by means of in-depth interviews with 15 women survivors of this experience, performed from January to September 2017. Obtained data were processed through discourse analysis and interpreted based on the four dimensions of the phenomenology of perception, namely: body, time, space, and relationality. Despite perceiving the complications at early stages, interviewees waited for objective symptoms before seeking for healthcare. According to them, timely treatment seeking did not imply an adequate management. Moreover, these women also reported insufficient support from both formal and informal networks in the provision of specialized treatment. Society and government must articulate strategies that empower women for the attention to obstetric emergencies, besides implementing actions that promote their self-care while guaranteeing timely and specialized care.


Assuntos
Humanos , Feminino , Gravidez , Pesquisa Qualitativa , Emergências , Obstetrícia
18.
Pharmaceutics ; 13(8)2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-34452219

RESUMO

Conjugated polymer nanoparticles (CPNs) have emerged as advanced polymeric nanoplatforms in biomedical applications by virtue of extraordinary properties including high fluorescence brightness, large absorption coefficients of one and two-photons, and excellent photostability and colloidal stability in water and physiological medium. In addition, low cytotoxicity, easy functionalization, and the ability to modify CPN photochemical properties by the incorporation of dopants, convert them into excellent theranostic agents with multifunctionality for imaging and treatment. In this work, CPNs were designed and synthesized by incorporating a metal oxide magnetic core (Fe3O4 and NiFe2O4 nanoparticles, 5 nm) into their matrix during the nanoprecipitation method. This modification allowed the in vivo monitoring of nanoparticles in animal models using magnetic resonance imaging (MRI) and intravital fluorescence, techniques widely used for intracranial tumors evaluation. The modified CPNs were assessed in vivo in glioblastoma (GBM) bearing mice, both heterotopic and orthotopic developed models. Biodistribution studies were performed with MRI acquisitions and fluorescence images up to 24 h after the i.v. nanoparticles administration. The resulting IONP-doped CPNs were biocompatible in GBM tumor cells in vitro with an excellent cell incorporation depending on nanoparticle concentration exposure. IONP-doped CPNs were detected in tumor and excretory organs of the heterotopic GBM model after i.v. and i.t. injection. However, in the orthotopic GBM model, the size of the nanoparticles is probably hindering a higher effect on intratumorally T2-weighted images (T2WI) signals and T2 values. The photodynamic therapy (PDT)-cytotoxicity of CPNs was not either affected by the IONPs incorporation into the nanoparticles.

19.
Am J Sports Med ; 49(8): 2165-2176, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34048286

RESUMO

BACKGROUND: Few randomized controlled trials with a midterm follow-up have compared matrix-assisted autologous chondrocyte transplantation (MACT) with microfracture (MFx) for knee cartilage lesions. PURPOSE: To compare the structural, clinical, and safety outcomes at midterm follow-up of MACT versus MFx for treating symptomatic knee cartilage lesions. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: A total of 48 patients aged between 18 and 50 years, with 1- to 4-cm2 International Cartilage Repair Society (ICRS) grade III to IV knee chondral lesions, were randomized in a 1:1 ratio to the MACT and MFx treatment groups. A sequential prospective evaluation was performed using magnetic resonance imaging (MRI) T2 mapping, the MOCART (magnetic resonance observation of cartilage repair tissue) score, second-look arthroscopic surgery, patient-reported outcome measures, the responder rate (based on achieving the minimal clinically important difference for the Knee injury and Osteoarthritis Outcome Score [KOOS] pain and KOOS Sport/Recreation), adverse events, and treatment failure (defined as a reoperation because of symptoms caused by the primary defect and the detachment or absence of >50% of the repaired tissue during revision surgery). RESULTS: Overall, 35 patients (18 MACT and 17 MFx) with a mean chondral lesion size of 1.8 ± 0.8 cm2 (range, 1-4 cm2) were followed up to a mean of 6 years postoperatively (range, 4-9 years). MACT demonstrated significantly better structural outcomes than MFx at 1 to 6 years postoperatively. At final follow-up, the MRI T2 mapping values of the repaired tissue were 37.7 ± 8.5 ms for MACT versus 46.4 ± 8.5 ms for MFx (P = .003), while the MOCART scores were 59.4 ± 17.3 and 42.4 ± 16.3, respectively (P = .006). More than 50% defect filling was seen in 95% of patients at 2 years and 82% at 6 years in the MACT group and in 67% at 2 years and 53% at 6 years in the MFx group. The second-look ICRS scores at 1 year were 10.7 ± 1.3 for MACT and 9.0 ± 1.8 for MFx (P = .001). Both groups showed significant clinical improvements at 6 years postoperatively compared with their preoperative status. Significant differences favoring the MACT group were observed at 2 years on the KOOS Activities of Daily Living (P = .043), at 4 years on all KOOS subscales (except Symptoms; P < .05) and the Tegner scale (P = .008), and at 6 years on the Tegner scale (P = .010). The responder rates at 6 years were 53% and 77% for MFx and MACT, respectively. There were no reported treatment failures after MACT; the failure rate was 8.3% in the MFx group. Neither group had serious adverse events related to treatment. CONCLUSION: Patients who underwent MACT had better structural outcomes than those who underwent MFx at 1 to 6 years postoperatively. Both groups of patients showed significant clinical improvements at final follow-up compared with their preoperative status. MACT showed superiority at 4 years for the majority of the KOOS subscales and for the Tegner scale at 4 to 6 years. The MACT group also had a higher responder rate and lower failure rate at final follow-up. REGISTRATION: NCT01947374 (ClinicalTrials.gov identifier).


Assuntos
Cartilagem Articular , Fraturas de Estresse , Atividades Cotidianas , Adolescente , Adulto , Cartilagem Articular/cirurgia , Condrócitos , Seguimentos , Humanos , Articulação do Joelho/cirurgia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Estudos Prospectivos , Transplante Autólogo , Adulto Jovem
20.
PeerJ ; 9: e10626, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33552718

RESUMO

The particleboard industry faces problems of wood shortage, which has led to the use of non-wood lignocellulosic materials. Furthermore, there is also interest in looking for materials that improve their physical and mechanical properties. The species Luffa aegyptiaca Mill. (fruit), Agave durangensis Gentry (bagasse) and Pennisetum sp. (plant, leaves and stem) could be used in the elaboration of wood-based particleboards. The aim of this study is to determine the feasibility of using these materials to produce particleboards in accordance with their chemical composition. Five materials were studied, A. durangensis (bagasse), L. aegyptiaca (fruit) and Pennisetum sp. (whole plant, leaves and stem). Extractives, holocellulose, Runkel lignin and ash content was determined. The pH of the fibers was also measured and a microanalysis of the ash was performed. ANOVA and Kruskal-Wallis tests were carried out, in addition Tukey and Dunn tests for group comparison were performed. Pennisetum sp. leaves presented the highest total extractives and ash content, while L. aegyptiaca fruit and A. durangensis bagasse had the highest both content of holocellulose and Runkel lignin respectively. The lowest pH was presented by the L. aegyptiaca fruit, while the highest was from the Pennisetum sp. stem. The element with the greatest presence in the five materials was potassium, except in A. durangensis bagasse showing calcium. L. aegyptiaca fruit has better characteristics to be used in particleboards with greater mechanical resistance because of its higher holocellulose content. However, Pennisetum sp. (plant, leaves and stem) could be used to make particleboards with high resistance to water absorption.

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