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1.
J Biotechnol ; 333: 86-96, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33940052

RESUMO

MicroRNAs are increasingly being used to enhance relevant pathways of interest during CHO cell line development and to optimise biopharmaceutical production processes. Previous studies have demonstrated that genetic manipulation of microRNAs has led to the development of highly productive phenotypes by increasing cell density through modifying the cell cycle, extending the culture lifespan by delaying apoptotic mechanisms, or improving the energetic flux by targeting mitochondrial metabolism. Re-programming mitochondrial metabolism has arisen as a potential area of interest due to the potential to decrease the Warburg effect and increase cell specific productivity with significant impact on the manufacture of recombinant therapeutic proteins. In this study, we have demonstrated a role for miR-31* to enhance specific productivity in CHO cells by boosting oxidative phosphorylation in the mitochondria. A detailed analysis of the mitochondrial metabolism revealed that miR-31* transfection increases basal oxygen consumption and spare respiratory capacity that leads to an increase in ATP production. Additionally, a proteomic analysis unveiled a number of potential targets involved in fatty acid metabolism and the TCA cycle, both implicated in mitochondrial metabolism. This data demonstrates a potential role for miR-31* to reprogramme the mitochondrial energetic metabolism and increase recombinant protein production in CHO cells.


Assuntos
MicroRNAs , Proteômica , Animais , Células CHO , Cricetinae , Cricetulus , MicroRNAs/genética , MicroRNAs/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Fosforilação Oxidativa , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transfecção
2.
Front Microbiol ; 10: 655, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31001231

RESUMO

In Western Europe, the HIV-1 epidemic among men who have sex with men (MSM) is dominated by subtype B. However, recently, other genetic forms have been reported to circulate in this population, as evidenced by their grouping in clusters predominantly comprising European individuals. Here we describe four large HIV-1 non-subtype B clusters spreading among MSM in Spain. Samples were collected in 9 regions. A pol fragment was amplified from plasma RNA or blood-extracted DNA. Phylogenetic analyses were performed via maximum likelihood, including database sequences of the same genetic forms as the identified clusters. Times and locations of the most recent common ancestors (MRCA) of clusters were estimated with a Bayesian method. Five large non-subtype B clusters associated with MSM were identified. The largest one, of F1 subtype, was reported previously. The other four were of CRF02_AG (CRF02_1; n = 115) and subtypes A1 (A1_1; n = 66), F1 (F1_3; n = 36), and C (C_7; n = 17). Most individuals belonging to them had been diagnosed of HIV-1 infection in the last 10 years. Each cluster comprised viruses from 3 to 8 Spanish regions and also comprised or was related to viruses from other countries: CRF02_1 comprised a Japanese subcluster and viruses from 8 other countries from Western Europe, Asia, and South America; A1_1 comprised viruses from Portugal, United Kingom, and United States, and was related to the A1 strain circulating in Greece, Albania and Cyprus; F1_3 was related to viruses from Romania; and C_7 comprised viruses from Portugal and was related to a virus from Mozambique. A subcluster within CRF02_1 was associated with heterosexual transmission. Near full-length genomes of each cluster were of uniform genetic form. Times of MRCAs of CRF02_1, A1_1, F1_3, and C_7 were estimated around 1986, 1989, 2013, and 1983, respectively. MRCA locations for CRF02_1 and A1_1 were uncertain (however initial expansions in Spain in Madrid and Vigo, respectively, were estimated) and were most probable in Bilbao, Spain, for F1_3 and Portugal for C_7. These results show that the HIV-1 epidemic among MSM in Spain is becoming increasingly diverse through the expansion of diverse non-subtype B clusters, comprising or related to viruses circulating in other countries.

4.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 34(4): 237-242, abr. 2016. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-151989

RESUMO

INTRODUCCIÓN: Descripción clínica y epidemiológica de un brote en una unidad de cuidados intensivos (UCI) causado por Enterobacter cloacae complex multirresistente productor de una beta-lactamasa de espectro extendido (BLEE) tipo CTX-M-9. MÉTODOS: Se realizó un estudio retrospectivo de las características clínicas y epidemiológicas del brote causado por E. cloacae complex. La identificación y estudio de sensibilidad de las cepas fueron realizados mediante el sistema semiautomático BD Phoenix™, y la caracterización de la BLEE, por PCR y secuenciación. La tipificación molecular se realizó mediante electroforesis en gel de campo pulsado (PFGE). RESULTADOS: Durante febrero de 2014, 6 pacientes (50% mujeres; media de edad: 61,5 años; rango de edad: 44-76 años) ingresados en la UCI del Complejo Hospitalario de Pontevedra (CHOP) presentaron aislamientos de E. cloacae complex resistente a cefalosporinas de amplio espectro. Tres pacientes desarrollaron infección; uno presentó bacteriemia primaria y shock séptico, y 2 neumonía asociada a ventilación mecánica. En los 3 casos restantes los aislamientos de E. cloacae complex se consideraron colonización. El análisis fenotípico y genotípico reveló que todos los aislados presentaban el mismo perfil por PFGE y que portaban la misma BLEE del tipo CTX-M-9. El brote se controló mediante la mejora de las medidas universales y el aislamiento de contacto de los pacientes infectados y/o colonizados. CONCLUSIÓN: Se describe desde un punto de vista clínico y epidemiológico un brote de E. cloacae complex portador de CTX-M-9 en una UCI


INTRODUCTION: Clinical and epidemiological description of an outbreak in an intensive care unit (ICU) caused by a strain of multidrug-resistant Enterobacter cloacae complex carrying a CTX-M-9-type extended-spectrum beta-lactamase (ESBL). METHODS: A retrospective study of the clinical and epidemiological features of the outbreak caused by E. cloacaecomplex was performed. Identifying and studying the sensitivity of the strains were performed using the semi-automated system BD Phoenix™, and the characterisation of ESBL using PCR and sequencing. Molecular typing was performed by pulsed-field gel electrophoresis (PFGE). RESULTS: During February 2014, 6 patients (50% women; mean age: 61.5 years; age range: 44-76 years) admitted to the ICU of the Hospital of Pontevedra (CHOP) presented resistant E. cloacae complex isolates to extended-spectrum cephalosporins. Three patients developed infection; one had primary bacteraemia and septic shock, and 2 with ventilator-associated pneumonia. In the remaining three cases E. cloacae complex isolates were considered as colonisation. Phenotypic and genotypic analysis revealed that all isolates had the same PFGE profile and carried the same CTX-M-9 ESBL. The outbreak was controlled by improving universal precautions and contact isolation of patients infected and/or colonized. CONCLUSION: The clinical and epidemiological features of an outbreak in an ICU caused by E. cloacae complex carrying CTX-M-9 are described


Assuntos
Humanos , Enterobacter cloacae/patogenicidade , Infecções por Enterobacteriaceae/epidemiologia , Infecção Hospitalar/epidemiologia , Surtos de Doenças , Resistência a Múltiplos Medicamentos/imunologia , beta-Lactamas/imunologia
5.
Enferm Infecc Microbiol Clin ; 34(4): 237-42, 2016 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-26139302

RESUMO

INTRODUCTION: Clinical and epidemiological description of an outbreak in an intensive care unit (ICU) caused by a strain of multidrug-resistant Enterobacter cloacae complex carrying a CTX-M-9-type extended-spectrum ß-lactamase (ESBL). METHODS: A retrospective study of the clinical and epidemiological features of the outbreak caused by E.cloacae complex was performed. Identifying and studying the sensitivity of the strains were performed using the semi-automated system BD Phoenix™, and the characterisation of ESBL using PCR and sequencing. Molecular typing was performed by pulsed-field gel electrophoresis (PFGE). RESULTS: During February 2014, 6 patients (50% women; mean age: 61.5 years; age range: 44-76 years) admitted to the ICU of the Hospital of Pontevedra (CHOP) presented resistant E.cloacae complex isolates to extended-spectrum cephalosporins. Three patients developed infection; one had primary bacteraemia and septic shock, and 2 with ventilator-associated pneumonia. In the remaining three cases E.cloacae complex isolates were considered as colonisation. Phenotypic and genotypic analysis revealed that all isolates had the same PFGE profile and carried the same CTX-M-9 ESBL. The outbreak was controlled by improving universal precautions and contact isolation of patients infected and/or colonized. CONCLUSION: The clinical and epidemiological features of an outbreak in an ICU caused by E.cloacae complex carrying CTX-M-9 are described.


Assuntos
Surtos de Doenças , Farmacorresistência Bacteriana Múltipla , Enterobacter cloacae/efeitos dos fármacos , Infecções por Enterobacteriaceae/epidemiologia , Unidades de Terapia Intensiva , Adulto , Idoso , Eletroforese em Gel de Campo Pulsado , Enterobacter cloacae/enzimologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , beta-Lactamases
6.
Brain Struct Funct ; 221(1): 665-78, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25366972

RESUMO

The retroflex tract contains medial habenula efferents that target the hindbrain interpeduncular complex and surrounding areas. This tract displays a singular course. Initially, habenular axons extend ventralwards in front of the pretectum until they reach the basal plate. Next, they avoid crossing the local floor plate, sharply changing course caudalwards (the retroflexion alluded by the tract name) and navigate strictly antero-posteriorly across basal pretectum, midbrain and isthmus. Once they reach rhombomere 1, the habenular axons criss-cross the floor plate several times within the interpeduncular nuclear complex as they innervate it. Here we described the timing and details of growth phenomena as these axons navigate to their target. The first dorsoventral course apparently obeys Ntn1 attraction. We checked the role of local floor plate signaling in the decision to avoid the thalamic floor plate and bend caudalwards. Analyzing the altered floor and basal plates of Gli2 knockout mice, we found a contralateral projection of most habenular axons, plus ulterior bizarre navigation rostralwards. This crossing phenotype was due to a reduced expression of Slit repulsive cues, suggesting involvement of the floor-derived Robo-Slit system in the normal guidance of this tract. Using Slit and Robo mutant mice, open neural tube and co-culture assays, we determined that Robo1-Slit2 interaction is specifically required for impeding that medial habenular axons cross the thalamic floor plate. This pathfinding mechanism is essential to establish the functionally important habenulo-interpeduncular connection.


Assuntos
Movimento Celular , Habenula/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Receptores Imunológicos/metabolismo , Tálamo/metabolismo , Animais , Axônios/metabolismo , Células COS , Chlorocebus aethiops , Técnicas de Cocultura , Regulação da Expressão Gênica no Desenvolvimento , Genótipo , Idade Gestacional , Habenula/embriologia , Peptídeos e Proteínas de Sinalização Intercelular/deficiência , Peptídeos e Proteínas de Sinalização Intercelular/genética , Fatores de Transcrição Kruppel-Like/deficiência , Fatores de Transcrição Kruppel-Like/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Fenótipo , Receptores Imunológicos/deficiência , Receptores Imunológicos/genética , Transdução de Sinais , Tálamo/embriologia , Técnicas de Cultura de Tecidos , Transfecção , Proteína Gli2 com Dedos de Zinco
7.
Brain Struct Funct ; 221(3): 1403-12, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25579066

RESUMO

In embryonic development, the neurons that will constitute a heterogeneous nucleus may have distinct origins. The different components of these populations reach their final location by radial and tangential migrations. The Substantia nigra pars reticulata (SNR) presents a high level of neuronal heterogeneity. It is composed by GABAergic neurons located in the mes-diencephalic basal plate. These inhibitory neurons usually display tangential migrations and it has been already described that the caudal SNR is colonized tangentially from rhombomere 1. Our aim is to unveil the origin of the rostral SNR. We have localized a Nkx6.2 positive ventricular domain located in the alar midbrain. Nkx6.2 derivatives' fate map analysis showed mainly a rostral colonization of this GABAergic neuronal population. We confirmed the mesencephalic origin by the expression of Six3. Both transcription factors are sequentially expressed along the differentiation of these neurons. We demonstrated the origin of the rostral SNR; our data allowed us to postulate that this nucleus is composed by two neuronal populations distributed in opposite gradients with different origins, one from rhombomere 1, caudal to rostral, and the other from the midbrain, rostral to caudal. We can conclude that the SNR has multiple origins and follows complex mechanisms of specification and migration. Our results support vital information for the study of genetic modifications in these extremely complex processes that result in devastating behavioral alterations and predisposition to psychiatric diseases. Understanding the development, molecular identity and functional characteristics of these diverse neuronal populations might lead to better diagnosis and treatment of several forms of neurological and psychiatric disease.


Assuntos
Neurônios GABAérgicos/metabolismo , Proteínas de Homeodomínio/metabolismo , Parte Reticular da Substância Negra/embriologia , Parte Reticular da Substância Negra/metabolismo , Fatores de Transcrição/metabolismo , Animais , Movimento Celular , Proteínas do Olho/metabolismo , Feminino , Neurônios GABAérgicos/fisiologia , Masculino , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/metabolismo
8.
Front Neuroanat ; 9: 12, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25741244

RESUMO

In the study of central nervous system morphogenesis, the identification of new molecular markers allows us to identify domains along the antero-posterior and dorso-ventral (DV) axes. In the past years, the alar and basal plates of the midbrain have been divided into different domains. The precise location of the alar-basal boundary is still under discussion. We have identified Barhl1, Nhlh1 and Six3 as appropriate molecular markers to the adjacent domains of this transition. The description of their expression patterns and the contribution to the different mesencephalic populations corroborated their role in the specification of these domains. We studied the influence of Sonic Hedgehog on these markers and therefore on the specification of these territories. The lack of this morphogen produced severe alterations in the expression pattern of Barhl1 and Nhlh1 with consequent misspecification of the basolateral (BL) domain. Six3 expression was apparently unaffected, however its distribution changed leading to altered basal domains. In this study we confirmed the localization of the alar-basal boundary dorsal to the BL domain and demonstrated that the development of the BL domain highly depends on Shh.

9.
Fungal Biol ; 119(2-3): 154-69, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25749367

RESUMO

Chitosan permeabilizes plasma membrane and kills sensitive filamentous fungi and yeast. Membrane fluidity and cell energy determine chitosan sensitivity in fungi. A five-fold reduction of both glucose (main carbon (C) source) and nitrogen (N) increased 2-fold Neurospora crassa sensitivity to chitosan. We linked this increase with production of intracellular reactive oxygen species (ROS) and plasma membrane permeabilization. Releasing N. crassa from nutrient limitation reduced chitosan antifungal activity in spite of high ROS intracellular levels. With lactate instead of glucose, C and N limitation increased N. crassa sensitivity to chitosan further (4-fold) than what glucose did. Nutrient limitation also increased sensitivity of filamentous fungi and yeast human pathogens to chitosan. For Fusarium proliferatum, lowering 100-fold C and N content in the growth medium, increased 16-fold chitosan sensitivity. Similar results were found for Candida spp. (including fluconazole resistant strains) and Cryptococcus spp. Severe C and N limitation increased chitosan antifungal activity for all pathogens tested. Chitosan at 100 µg ml(-1) was lethal for most fungal human pathogens tested but non-toxic to HEK293 and COS7 mammalian cell lines. Besides, chitosan increased 90% survival of Galleria mellonella larvae infected with C. albicans. These results are of paramount for developing chitosan as antifungal.


Assuntos
Antifúngicos/farmacologia , Carbono/metabolismo , Quitosana/farmacologia , Neurospora crassa/efeitos dos fármacos , Neurospora crassa/metabolismo , Nitrogênio/metabolismo , Animais , Células COS , Candida/efeitos dos fármacos , Candida/metabolismo , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular , Chlorocebus aethiops , Cryptococcus/efeitos dos fármacos , Cryptococcus/metabolismo , Meios de Cultura/química , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Fusarium/efeitos dos fármacos , Fusarium/metabolismo , Glucose/metabolismo , Células HEK293 , Humanos , Lactatos/metabolismo , Viabilidade Microbiana/efeitos dos fármacos , Permeabilidade/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/toxicidade
10.
Front Neuroanat ; 9: 8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25698939

RESUMO

The red nucleus (RN) is a neuronal population that plays an important role in forelimb motor control and locomotion. Histologically it is subdivided into two subpopulations, the parvocellular RN (pRN) located in the diencephalon and the magnocellular RN (mRN) in the mesencephalon. The RN integrates signals from motor cortex and cerebellum and projects to spinal cord interneurons and motor neurons through the rubrospinal tract (RST). Pou4f1 is a transcription factor highly expressed in this nucleus that has been related to its specification. Here we profoundly analyzed consequences of Pou4f1 loss-of-function in development, maturation and axonal projection of the RN. Surprisingly, RN neurons are specified and maintained in the mutant, no cell death was detected. Nevertheless, the nucleus appeared disorganized with a strong delay in radial migration and with a wider neuronal distribution; the neurons did not form a compacted population as they do in controls, Robo1 and Slit2 were miss-expressed. Cplx1 and Npas1, expressed in the RN, are transcription factors involved in neurotransmitter release, neuronal maturation and motor function processes among others. In our mutant mice, both transcription factors are lost, suggesting an abnormal maturation of the RN. The resulting altered nucleus occupied a wider territory. Finally, we examined RST development and found that the RN neurons were able to project to the spinal cord but their axons appeared defasciculated. These data suggest that Pou4f1 is necessary for the maturation of RN neurons but not for their specification and maintenance.

11.
Glia ; 62(10): 1713-23, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24963847

RESUMO

Growth differentiation factor 10 (Gdf10), also known as Bmp3b, is a member of the transforming growth factor (TGF)-ß superfamily. Gdf10 is expressed in Bergmann glial cells, which was investigated by single-cell transcriptional profiling (Koirala and Corfas, (2010) PLoS ONE 5: e9198). Here we provide a detailed characterization of Gdf10 expression from E14, the stage at which Gdf10 is expressed for the first time in the cerebellum, until P28. We detected Gdf10 expression in both germinal zones: in the ventricular zone (VZ) of the 4th ventricle as well as in the rhombic lip (RL). The VZ has been postulated to give rise to GABAergic neurons and glial cells, whereas the RL gives rise to glutamatergic neurons. Thus, it was very surprising to discover a gene that is expressed exclusively in glial cells and is not restricted to an expression in the VZ, but is also present in the RL. At postnatal stages Gdf10 was distributed equally in Bergmann glial cells of the cerebellum. Furthermore, we found Gdf10 to be regulated by Sonic hedgehog (Shh), which is secreted by Purkinje cells of the cerebellum. In the conditional Shh mutants, glial cells showed a reduced expression of Gdf10, whereas the expression of Nestin and Vimentin was unchanged. Thus, we show for the first time, that Gdf10, expressed in Bergmann glial cells, is affected by the loss of Shh as early as E18.5, suggesting a regulation of glial development by Shh.


Assuntos
Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Fator 10 de Diferenciação de Crescimento/metabolismo , Proteínas Hedgehog/metabolismo , Neuroglia/fisiologia , Animais , Proteínas Hedgehog/genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Camundongos Endogâmicos ICR , Camundongos Transgênicos , Nestina/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Vimentina/metabolismo
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