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1.
J Endocrinol Invest ; 47(6): 1447-1455, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38183564

RESUMO

BACKGROUND: Type 2 diabetes mellitus (T2DM) is usually accompanied by a low-grade inflammatory phenomenon, which participates in the pathogenesis of different complications of this condition. The inflammatory response is under the regulation of different mechanisms, including T regulatory (Treg) lymphocytes. However, the possible role of type 1 T regulatory (Tr1) cells in T2DM has not been explored so far. AIM: To carry out a quantitative analysis of Tr1 lymphocytes and other immune cell subsets in patients with T2DM and correlate these results with clinical findings and treatments. MATERIALS AND METHODS: Sixty patients with T2DM and twenty-three healthy controls were included in the study. Biochemical and anthropometric variables were evaluated, and Tr1 lymphocytes (CD4+CD49+LAG-3+IL-10+) and other cell subsets (Th17, Th22 and Foxp3 + Treg cells) were analyzed in peripheral blood samples by multiparametric flow cytometry. RESULTS: Significant increased levels of Tr1 cells were detected in patients with severe and mild disease, compared to healthy controls. In addition, CD4+IL-10+ lymphocytes were also increased in patients with T2DM. In contrast, similar levels of Foxp3+ Treg cells, Th17 and Th22 lymphocytes were observed in patients and controls. Likewise, no significant associations were detected between Tr1 cell levels and different clinical and laboratory parameters. However, those patients receiving glucagon-like peptide-1 receptor agonists (GLP-1-RA) showed similar levels of Tr1 cells than healthy controls, and significant lower numbers than untreated patients. CONCLUSION: We observed an increase in Tr1 and CD4+IL10+ lymphocyte levels in T2DM. Moreover, GLP1-RA treatment was significantly associated with normalization of the Tr1 levels. This highlights another potential immune dysfunction in patients with T2DM, which could participate in the pathogenesis of this condition.


Assuntos
Diabetes Mellitus Tipo 2 , Linfócitos T Reguladores , Humanos , Diabetes Mellitus Tipo 2/imunologia , Diabetes Mellitus Tipo 2/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Linfócitos T Reguladores/imunologia , Estudos de Casos e Controles , Adulto , Idoso , Citometria de Fluxo/métodos
2.
Nanomedicine ; 29: 102259, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32619707

RESUMO

Sodium colistimethate (SCM) and amikacin (AMK) are among the few antibiotics effective against resistant P. aeruginosa, K. pneumoniae and A. baumannii; however, their toxicity severely limits their use. Enclosing antibiotics into nanostructured lipid carriers (NLC) might decrease drug toxicity and improve antibiotic disposition. In this work, SCM or AMK was loaded into different NLC formulations, through high pressure homogenization, and their in vitro and in vivo effectiveness was analyzed. The encapsulation process did not reduce drug effectiveness since in vitro SCM-NLC and AMK-NLC drug activity was equal to that of the free drugs. As cryoprotectant, trehalose showed better properties than dextran. Instead, positive chitosan coating was discarded due to its limited cost-efficiency. Finally, the in vivo study in acute pneumonia model revealed that intraperitoneal administration was superior to the intramuscular route and confirmed that (-) SCM-NLC with trehalose, was the most suitable formulation against an extensively drug-resistant A. baumannii strain.


Assuntos
Amicacina/química , Colistina/análogos & derivados , Farmacorresistência Bacteriana/efeitos dos fármacos , Nanoestruturas/química , Amicacina/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Colistina/química , Colistina/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Humanos , Lipídeos/química , Lipídeos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade
3.
Diabet Med ; 36(8): 1037-1045, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31087451

RESUMO

AIM: To evaluate the effects of Alimentación Normal con Ajuste de Insulina (ANAIS), a group-based, therapeutic education programme for Type 1 diabetes based on a flexible insulin regimen adjusted to the individual's food intake. METHODS: Participants with Type 1 diabetes and HbA1c levels of 53-86 mmol/mol (7-10%) were recruited from outpatient clinics at a tertiary care centre. They were randomized (using opaque, sealed envelopes, with a 2:1 treatment allocation ratio) to attend the training course immediately (immediate ANAIS; intervention group) or a year later (delayed ANAIS; control group). The main outcome was HbA1c level at 1 year. Secondary outcomes included lipid levels, weight, hypoglycaemic events, insulin dose, treatment satisfaction, self-perceived dietary freedom, quality of life and participant-defined goals. RESULTS: A total of 48 participants were assigned to the intervention group and 32 to the control group. Twelve months after completing the training, adjusted HbA1c was not significantly different in the intervention group [64 ± 1.3 vs 68 ± 1.6 mmol/mol (8.0 ±0.1% vs 8.4 ±0.1%); P=0.081]. Treatment satisfaction was significantly higher in the intervention group, but no differences were found in hypoglycaemic events, weight, insulin dose or changes in dietary freedom. At 1 year after the intervention, 72% of the participants (vs 33% in the control group; P=0.046) reported exceeding their expectations regarding achievement of their main personal goal. CONCLUSION: Promoting dietary freedom and empowering people with Type 1 diabetes through structured education programmes, such as ANAIS, improves treatment satisfaction and self-defined goals. No significant improvement in HbA1c level was achieved.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Educação de Pacientes como Assunto/métodos , Psicoterapia/métodos , Adulto , Peso Corporal/fisiologia , Protocolos Clínicos , Diabetes Mellitus Tipo 1/sangue , Ingestão de Energia , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Masculino , Resultado do Tratamento
4.
Acta Endocrinol (Buchar) ; 12(2): 224-226, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-31149091

RESUMO

CONTEXT: Spontaneous muscle infarction is a rare complication of diabetes mellitus, mainly affecting women and patients with long-lasting type 1 diabetes. OBJECTIVE: This report is aimed to describe the case of a patient with type 1 diabetes and diabetic nephropathy in whom a severe deterioration of renal function was triggered by a muscle infarction. SUBJECT AND METHODS: Subject of the study was a 33-years-old woman with an 18 years history of type 1 diabetes mellitus, proliferative diabetic retinopathy, nephropathy at stage 3 chronic kidney disease, somatic sensory-motor polyneuropathy and autonomic neuropathy. RESULTS: The patient presented with severe pain and dysfunction of the left thigh without prior trauma plus progressive deterioration of the renal function. Nuclear magnetic resonance of the thigh showed inflammatory changes in the external vastus with hyperintensity on T2 sequence and edema of the subcutaneous cellular tissue. After other possible etiologies were ruled out, a clinical diagnosis of spontaneous muscle infarction was established. The patient needed hospital admission for two months, during which the renal function worsened until she required hemodialysis. No other possible triggers of kidney injury were identified. CONCLUSIONS: Up to our knowledge, this is the first described case where muscle infarction is suspected to have caused exacerbation of an existing chronic kidney failure. Monitoring the renal function should be considered in patients with diabetic nephropathy presenting with this rare complication of diabetes.

5.
Artigo em Inglês | MEDLINE | ID: mdl-35869005

RESUMO

BACKGROUND AND OBJECTIVE: Metabolic equivalent of task (MET) is a physiological measure that represents the metabolic cost of an activity of daily living. One MET is equivalent to the resting metabolic rate. METs can be estimated by questionnaires or calculated by measuring maximal oxygen uptake (VO2max). The aim of this study is to determine whether METs estimated in the pre-consultation (METse) correlates with METs calculated from VO2max (METsVO2). PATIENTS AND METHODS: Retrospective observational study in patients scheduled for lung resection surgery. The estimation of METs was obtained in the pre-consultation according to the 2014 European and American guidelines for preoperative cardiovascular assessment in non-cardiac surgery. VO2max was calculated in the ergometry laboratory. RESULTS: A total of 104 patients were included in the study, of whom 25 (24%) were female. The mean age was 65.1 years (±9.8). In 26 patients (25%), the METse classification correlated with METsVO2 (κ = -0.107 P = .02). In the remaining patients, METse overestimated functional capacity measured by ergometry (METse > METsVO2). CONCLUSIONS: Subjective assessment overestimates functional capacity and should not replace objective testing in patients scheduled for lung resection surgery.


Assuntos
Teste de Esforço , Consumo de Oxigênio , Idoso , Feminino , Humanos , Pulmão , Masculino , Equivalente Metabólico/fisiologia , Consumo de Oxigênio/fisiologia , Estudos Retrospectivos
6.
Semergen ; 48(6): 403-410, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35606250

RESUMO

OBJECTIVE: The use of nutritional supplements to treat hypercholesterolemia is gradually increasing, however further studies on their efficacy and safety are required. PATIENTS AND METHODS: The present clinical trial included patients with moderate hypercholesterolemia and cardiovascular risk who were treated either with a nutraceutical preparation containing 3.75mg of monacolin K, 515mg of berberine and 50mg of coenzyme Q10 per tablet (Lipok®) or with a placebo. The clinical and laboratory variables were analyzed at baseline and at three and six months. None of the patients was diabetic, and none was being treated with lipid-lowering drugs or with any other nutritional supplements affecting lipid metabolism. RESULTS: In patients of the intervention group and of the placebo group, baseline LDL-C was 134.7mg/dL (14.4) and 138.7mg/dL (15.2), respectively. At three months after treatment start, LDL-C had decreased by 26.1mg/dL (-32.4 to 19.7) and increased by 4.5mg/dL (-1.5 to 10.5) in the respective groups. In the intervention group, a similar decrease in non-HDL-C and total cholesterol was observed, while no significant changes were observed in either group for HDL-C, triglycerides and lipoprotein(a). A good tolerance and safety profile was observed. CONCLUSION: In conclusion, this study demonstrates that the combination of monacolin K, berberine and coenzyme Q10 is effective and safe for treating hypercholesterolemia in patients with a moderate degree of excess LDL-C and cardiovascular risk.


Assuntos
Berberina , Doenças Cardiovasculares , Hipercolesterolemia , Berberina/efeitos adversos , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , LDL-Colesterol , Suplementos Nutricionais/efeitos adversos , Fatores de Risco de Doenças Cardíacas , Humanos , Hipercolesterolemia/tratamento farmacológico , Metabolismo dos Lipídeos , Lovastatina/farmacologia , Lovastatina/uso terapêutico , Fatores de Risco , Resultado do Tratamento , Ubiquinona/análogos & derivados
7.
J Microencapsul ; 28(7): 614-20, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21740107

RESUMO

Bovine serum albumin (BSA) loaded calcium alginate microparticles (MPs) produced in this study by a w/o emulsification and external gelation method exhibited spherical and fairly smooth and porous morphology with 1.052 ± 0.057 µm modal particle size. The high permeability of the calcium alginate hydrogel lead to a potent burst effect and too fast protein release. To overcome these problems, MPs were coated with polycations, such as chitosan, poly-L-lysine and DEAE-dextran. Our results demonstrated that coated MPs showed slower release and were able to significantly reduce the release of BSA in the first hour. Therefore, this method can be applied to prepare coated alginate MPs which could be an optimal system for the controlled release of biotherapeutic molecules. Nevertheless, further studies are needed to optimize delivery properties which could provide a sustained release of proteins.


Assuntos
Alginatos/administração & dosagem , Química Farmacêutica/métodos , Materiais Revestidos Biocompatíveis/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Poliaminas/administração & dosagem , Soroalbumina Bovina/administração & dosagem , Alginatos/química , Alginatos/farmacologia , Quitosana/administração & dosagem , Quitosana/química , Quitosana/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , DEAE-Dextrano/administração & dosagem , DEAE-Dextrano/química , DEAE-Dextrano/farmacologia , Desenho de Fármacos , Emulsões/química , Géis/química , Ácido Glucurônico/administração & dosagem , Ácido Glucurônico/química , Ácido Glucurônico/farmacologia , Ácidos Hexurônicos/administração & dosagem , Ácidos Hexurônicos/química , Ácidos Hexurônicos/farmacologia , Humanos , Nanopartículas/administração & dosagem , Nanopartículas/química , Tamanho da Partícula , Poliaminas/química , Poliaminas/farmacologia , Polieletrólitos , Polilisina/administração & dosagem , Polilisina/análogos & derivados , Polilisina/química , Polilisina/farmacologia , Soroalbumina Bovina/química , Soroalbumina Bovina/farmacologia
8.
Eur J Paediatr Dent ; 12(4): 220-4, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22185244

RESUMO

AIM: Streptococcus mutans and Streptococcus sobrinus are the main pathogens associated with the development of dental caries in humans. Recently, the real-time polymerase chain reaction (qPCR-TR) has been used for fast and exact quantification of these bacteria species. This molecular biology method has made the detection of these bacteria in saliva and dental plaque possible; additionally, it aids the development of illness risk prediction. The purpose of this prospective, analytic, transversal, observational and unicenter study was to quantify the spaP gene of the Streptococcus mutans and its correlation with caries in a group of children using isolated DNA from plaque samples processed through qPCR-TR, using specific oligonucleotides for this gene detection. MATERIALS AND METHODS: The cariogenic potential of Streptococcus mutans in the dental plaque was analysed in a group of patients aged 12 to 46 months. A descriptive statistical analysis was performed. The Spearman's correlation coefficient was used to establish the correlation between caries (dmft) index (decayed/missing/filled primary teeth), spaP gene and age group. The Wilcoxon test was used to compare MSB cultivation technique and qPCR-TR. RESULTS: In the molecular trials, a close association between caries prevalence in childhood and the presence and high proportion of the spaP gene of S. mutans was found. The average caries prevalence was 3.71, and it increased as age range increased. The highest caries prevalence was observed in female patients and in the oldest age range studied (40 46 months) which contrasts with the 12-18 months age that had a caries (dmft) index of zero. The amplification using as initiator the gene spaP of the nucleic acids extracted from the S. mutans resulted positive in 91.3% of the cases. Every child with caries was positive for the spaP and only 8.75% were negative, this group included children without caries. CONCLUSION: In conclusion, there was a correlation with infant caries prevalence and S. mutans.


Assuntos
Cárie Dentária/epidemiologia , Placa Dentária/microbiologia , Genes Bacterianos , Streptococcus mutans/genética , Fatores Etários , Pré-Escolar , Índice CPO , DNA Bacteriano/análise , Cárie Dentária/microbiologia , Feminino , Humanos , Lactente , Masculino , Prevalência , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Estatísticas não Paramétricas
9.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32616357

RESUMO

Complete obstructive atelectasis occurs when mucous or a foreign body obstruct one of the main bronchi. Several lung ultrasound signs have been associated with this entity. We describe the case of a patient admitted to the surgical critical care unit in whom lung ultrasound led to a diagnosis of complete obstructive atelectasis, and the presence of pleural effusion provided direct visualization of lung pulse, a sign that has only previously been described by interpreting ultrasound artifacts.


Assuntos
Pulmão/fisiopatologia , Derrame Pleural/fisiopatologia , Atelectasia Pulmonar/diagnóstico , Atelectasia Pulmonar/fisiopatologia , Idoso de 80 Anos ou mais , Estado Terminal , Feminino , Humanos , Derrame Pleural/etiologia , Atelectasia Pulmonar/complicações , Pulso Arterial , Insuficiência Respiratória/complicações
10.
Acta Ortop Mex ; 34(3): 189-194, 2020.
Artigo em Espanhol | MEDLINE | ID: mdl-33417757

RESUMO

INTRODUCTION: The floating shoulder has an incidence of 0.1% of all fractures, the result of high-energy trauma. There is still no consensus in the literature on the best treatment: surgical versus conservative. MATERIAL AND METHODS: Patients with floating shoulder diagnosis were evaluated from January 2013 to December 2018, collecting initial data from the electronic file. The morphological types of fractures were described using the Allman and AO classifications. Patients were evaluated using the UCLA scale for shoulder functionality. RESULTS: From 14 patients, 4 were excluded due to lack of follow-up. Of the remaining 10, 9 were men, 1 woman. The average age was 29 years (range 15-42 years). Three patients had left injury, and 7 patients, right; 6 patients hurt the dominant limb. The most common morphological pattern was glenoid neck fracture + clavicle fracture in 7 patients. Surgical treatment was indicated in 7 patients; and in 3, conservative. Of the 7 patients treated surgically, 6 were with clavicle and scapula osteosynthesis; 1 just the clavicle. Patients with conservative management used a universal shoulder immobilizer for 4-8 weeks. There were no cases of consolidation delay, pseudoarthrosis, or vicious consolidation. Rehabilitation began in the first 4 weeks, and lasted up to 8 weeks. CONCLUSION: Surgical treatment was predominant due to instability. Conservative treatment was used when injuries are minimally displaced. Both treatments generate a favorable functional result.


INTRODUCCIÓN: El hombro flotante tiene una incidencia de 0.1% de todas las fracturas, resultado de traumatismos de alta energía. Aún no existe consenso en la literatura sobre el mejor tratamiento: quirúrgico versus conservador. MATERIAL Y MÉTODOS: Se evaluaron individuos con diagnóstico de hombro flotante, de Enero 2013 a Diciembre 2018, recabando datos iniciales del archivo electrónico. Los tipos morfológicos de fracturas se describieron utilizando las clasificaciones de Allman y AO. Se valoraron los pacientes mediante la escala de la UCLA para la funcionalidad del hombro. RESULTADOS: De 14 pacientes, se excluyeron cuatro por falta de seguimiento. De los 10 restantes, nueve fueron hombres, una mujer. La edad promedio fue de 29 años (rango 15-42 años). Tres pacientes con lesión izquierda y los otros siete, derecha; seis de ellos se lesionaron la extremidad dominante. El patrón morfológico más común fue fractura de cuello de glenoides + fractura de clavícula en siete pacientes. En siete pacientes se indicó tratamiento quirúrgico; y en tres, conservador. De los siete individuos tratados quirúrgicamente, en seis se fijaron clavícula y escápula; en uno, solamente clavícula. Los pacientes con manejo conservador utilizaron inmovilizador universal de hombro por 4-8 semanas. No hubo casos de retardo en la consolidación, pseudoartrosis, ni consolidación viciosa. La rehabilitación inició en las primeras cuatro semanas y se prolongó hasta ocho semanas. CONCLUSIÓN: El tratamiento quirúrgico fue el predominante por inestabilidad. El tratamiento conservador se usó cuando las lesiones están poco desplazadas. Ambos tratamientos generan un resultado funcional favorable.


Assuntos
Fraturas Ósseas , Ombro , Adolescente , Adulto , Clavícula/diagnóstico por imagem , Clavícula/cirurgia , Feminino , Fixação Interna de Fraturas , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Humanos , Masculino , Escápula , Resultado do Tratamento , Adulto Jovem
12.
Int J Pharm ; 569: 118484, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31260785

RESUMO

Re-activation of the healing process is a major challenge in the field of chronic wound treatment. For that purpose, lipid-nanoparticles, especially nanostructured lipid carriers (NLC), possess extremely useful characteristics such as biodegradability, biocompatibility and long-term stability, besides being suitable for drug delivery. Moreover, they maintain wound moisture due to their occlusive properties, which have been associated with increased healing rates. In the light of above, NLC have been extensively used topically for wound healing; but to date, there are no safety-preclinical studies concerning such type of application. Thus, in this work, biodistribution studies were performed in rats with the NLC previously developed by our research group, using technetium-99 m (99mTc-NLC) as radiomarker, topically administered on a wound. 99mTc-NLC remained on the wound for 24 h and systemic absorption was not observed after administration. In addition, toxicological studies were performed to assess NLC safety after topical administration. The results obtained demonstrated that NLC were non-cytotoxic, non-sensitizing and non-irritant/corrosive. Overall, it might be concluded that developed NLC remained at the administration area, potentially exerting a local effect, and were safe after topical administration on wounds.


Assuntos
Portadores de Fármacos/administração & dosagem , Lipídeos/administração & dosagem , Nanoestruturas/administração & dosagem , Animais , Células 3T3 BALB , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/toxicidade , Feminino , Lipídeos/farmacocinética , Lipídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos CBA , Nanoestruturas/toxicidade , Coelhos , Ratos Wistar , Pele/efeitos dos fármacos , Testes de Irritação da Pele , Tecnécio , Distribuição Tecidual , Cicatrização/efeitos dos fármacos
13.
Int J Pharm ; 548(1): 206-216, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-29969709

RESUMO

The low-temperature storage of therapeutic cell-based products plays a crucial role in their clinical translation for the treatment of diverse diseases. Although dimethylsulfoxide (DMSO) is the most successful cryoprotectant in slow freezing of microencapsulated cells, it has shown adverse effects after cryopreserved cell-based products implantation. Therefore, the search of alternative non-toxic cryoprotectants for encapsulated cells is continuously investigated to move from bench to the clinic. In this work, we investigated the low molecular-weight hyaluronan (low MW-HA), a natural non-toxic and non-sulfated glycosaminoglycan, as an alternative non-permeant cryoprotectant for the slow freezing cryopreservation of encapsulated cells. Cryopreservation with low MW-HA provided similar metabolic activity, cell dead and early apoptotic cell percentage and membrane integrity after thawing, than encapsulated cells stored with either DMSO 10% or Cryostor 10. However, the beneficial outcomes with low MW-HA were not comparable to DMSO with some encapsulated cell types, such as the human insulin secreting cell line, 1.1B4, maybe explained by the different expression of the CD44 surface receptor. Altogether, we can conclude that low MW-HA represents a non-toxic natural alternative cryoprotectant to DMSO for the cryopreservation of encapsulated cells.


Assuntos
Criopreservação , Crioprotetores/farmacologia , Ácido Hialurônico/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Composição de Medicamentos , Humanos , Receptores de Hialuronatos/metabolismo , Peso Molecular
14.
J Control Release ; 281: 119-138, 2018 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-29782945

RESUMO

Over the past few decades, the use of cell microencapsulation technology has been promoted for a wide range of applications as sustained drug delivery systems or as cells containing biosystems for regenerative medicine. However, difficulty in their preservation and storage has limited their availability to healthcare centers. Because the preservation in cryogenic temperatures poses many biological and biophysical challenges and that the technology has not been well understood, the slow cooling cryopreservation, which is the most used technique worldwide, has not given full measure of its full potential application yet. This review will discuss the different steps that should be understood and taken into account to preserve microencapsulated cells by slow freezing in a successful and simple manner. Moreover, it will review the slow freezing preservation of alginate-based microencapsulated cells and discuss some recommendations that the research community may pursue to optimize the preservation of microencapsulated cells, enabling the therapy translate from bench to the clinic.


Assuntos
Criopreservação/métodos , Composição de Medicamentos/métodos , Alginatos/química , Animais , Temperatura Baixa , Sistemas de Liberação de Medicamentos/métodos , Congelamento , Humanos , Medicina Regenerativa/métodos
15.
Trends Biotechnol ; 36(4): 445-456, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29455936

RESUMO

Encapsulating, or immunoisolating, insulin-secreting cells within implantable, semipermeable membranes is an emerging treatment for type 1 diabetes. This approach can eliminate the need for immunosuppressive drug treatments to prevent transplant rejection and overcome the shortage of donor tissues by utilizing cells derived from allogeneic or xenogeneic sources. Encapsulation device designs are being optimized alongside the development of clinically viable, replenishable, insulin-producing stem cells, for the first time creating the possibility of widespread therapeutic use of this technology. Here, we highlight the status of the most advanced and widely explored implementations of cell encapsulation with an eye toward translating the potential of this technological approach to medical reality.


Assuntos
Órgãos Bioartificiais , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 1/terapia , Pâncreas Artificial , Engenharia Tecidual , Animais , Ensaios Clínicos como Assunto , Humanos , Células Secretoras de Insulina/química , Células Secretoras de Insulina/transplante , Teste de Materiais , Membranas Artificiais , Modelos Animais
17.
Methods Mol Biol ; 1479: 207-216, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27738938

RESUMO

Alginate cell microencapsulation implies the immobilization of cells within a polymeric membrane that allows the bidirectional diffusion of nutrients and oxygen inside the microcapsules and the release of waste and therapeutic molecules outside them. This technology has been applied to several cell types and it has been extensively described with pancreatic islets. However, other cells such as myoblasts are being currently studied and showing high interest. Moreover, different systems and approaches have been developed for cell encapsulation such as electrostatic extrusion and Flow focusing technology. When Flow focusing technology is applied for myoblast encapsulation, several factors should be considered, such as the pressure, the flow of the system, or the diameter size of the nebulizer, which will determine the final diameter size and shape of the microcapsules containing the myoblasts. Finally, viability of encapsulated myoblasts needs to be assessed before further studies are performed.


Assuntos
Alginatos/química , Células Imobilizadas/citologia , Composição de Medicamentos/instrumentação , Mioblastos/citologia , Animais , Cápsulas/química , Sobrevivência Celular , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos , Desenho de Equipamento , Eritropoetina/administração & dosagem , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Pressão
18.
Methods Mol Biol ; 1479: 261-272, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27738943

RESUMO

The microencapsulation of different types of cells that are able to produce therapeutic factors is being investigated for the treatment of several human diseases. Most efforts are focused on chronic and degenerative diseases as this strategy could become an alternative to some commonly used parenteral treatments that need to be repeatedly administered. But, this approach has also been investigated in the field of oncology with the aim of providing immunomodulatory antibodies that are able to enhance the patient's inherent immune response against the tumor. These kind of treatments would provide the patient with the therapeutic drug produced in situ, de novo, and in a sustained way, making the therapy more comfortable.Although different devices are nowadays available to produce cell-enclosing alginate-microcapsules, here, we describe the most important steps and advices in order to fabricate alginate-poly-L-lysine-alginate microcapsules containing hybridoma cells for cancer management using an electrostatic bead generator, and how to evaluate the viability of those cells over the time.


Assuntos
Alginatos/química , Cápsulas/química , Células Imobilizadas/citologia , Hibridomas/citologia , Neoplasias/terapia , Polilisina/análogos & derivados , Animais , Contagem de Células , Linhagem Celular , Sobrevivência Celular , Terapia Baseada em Transplante de Células e Tecidos/métodos , Células Imobilizadas/metabolismo , Células Imobilizadas/transplante , Composição de Medicamentos/instrumentação , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos , Desenho de Equipamento , Humanos , Hibridomas/metabolismo , Hibridomas/transplante , Polilisina/química , Eletricidade Estática
19.
Mol Neurobiol ; 54(10): 7722-7735, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27844282

RESUMO

The unilateral 6-hydroxydopamine (6-OHDA) lesion of medial forebrain bundle (MFB) in rats affords us to study the advanced stages of Parkinson's disease (PD). Numerous evidences suggest synergic effects when various neurotrophic factors are administered in experimental models of PD. The aim of the present work was to assess the morphological changes along the rostro-caudal axis of caudo-putamen complex and substantia nigra (SN) in the referred model in order to test the suitability of a severe model to evaluate new neurorestorative therapies. Administration of 6-OHDA into MFB in addition to a remarkable depletion of dopamine in the nigrostriatal system induced an increase of glial fibrillary acidic protein (GFAP)-positive cells in SN and an intense immunoreactivity for OX-42, vascular endothelial growth factor (VEGF), and Lycopersycum esculentum agglutinin (LEA) in striatum and SN. Tyrosine hydroxylase (TH) immunostaining revealed a significant decrease of the TH-immunopositive striatal volume in 6-OHDA group from rostral to caudal one. The loss of TH-immunoreactive (TH-ir) neurons and axodendritic network (ADN) was higher in caudal sections. Morphological recovery after the implantation of microspheres loaded with VEGF and glial cell line-derived neurotrophic factor (GDNF) in parkinsonized rats was related to the preservation of the TH-ir cell number and ADN in the caudal region of the SN. In addition, these findings support the neurorestorative role of VEGF+GDNF in the dopaminergic system and the synergistic effect between both factors. On the other hand, a topological distribution of the dopaminergic system was noticeable in the severe model, showing a selective vulnerability to 6-OHDA and recovering after treatment.


Assuntos
Composição de Medicamentos , Fator Neurotrófico Derivado de Linhagem de Célula Glial/administração & dosagem , Transtornos Parkinsonianos/tratamento farmacológico , Transtornos Parkinsonianos/patologia , Índice de Gravidade de Doença , Fator A de Crescimento do Endotélio Vascular/administração & dosagem , Animais , Composição de Medicamentos/métodos , Feminino , Fármacos Neuroprotetores/administração & dosagem , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
20.
Sci Total Environ ; 575: 1203-1210, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27697347

RESUMO

Knowledge of the arbuscular mycorrhizal fungal assemblages in the Trachypogon savanna ecosystems is very important to a better understanding of the ecological processes mediated by this soil microbial group that affects multiple ecosystem functions. Considering the hypothesis that the biocrusts can be linked to vegetation through the arbuscular fungi mycelial network, the objectives proposed in this study were to determine (i) whether there are arbuscular mycorrhizal fungi (AMF) in the biocrusts (ii) whether arbuscular mycorrhizal fungal assemblages are linked to the Trachypogon patches, and (iii) whether the composition of the assemblages is related to soil properties affected by microbiological activity. The community structure of the AMF was investigated in three habitats: rhizospheric soil and roots of Trachypogon vestitus, biological soil crusts, and bare soil. The canonical correspondence analysis showed that two soil properties related to enzymatic activity (protease and ß-glucosidase) significantly affected the community composition of the AMF. The biocrusts in the Venezuelan savanna are colonized by an AM fungal community linked to that of the bare soil and significantly different from that hosted by the roots of the surrounding T. vestitus, suggesting that assemblages of AMF in biocrusts might be related more closely to those of annual plant species appearing in favorable conditions.


Assuntos
Pradaria , Micorrizas , Poaceae , Microbiologia do Solo , Ecossistema , Raízes de Plantas , Rizosfera , Solo , Venezuela
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