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1.
Cell ; 186(19): 4152-4171.e31, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37669667

RESUMO

Social preference, the decision to interact with one member of the same species over another, is critical to optimize social interactions. Thus, adult rodents favor interacting with novel conspecifics over familiar ones, but whether this social preference stems from neural circuits facilitating interactions with novel individuals or suppressing interactions with familiar ones remains unknown. Here, we identify neurons in the infra-limbic area (ILA) of the mouse prefrontal cortex that express the neuropeptide corticotropin-releasing hormone (CRH) and project to the dorsal region of the rostral lateral septum (rLS). We show how release of CRH during familiar encounters disinhibits rLS neurons, thereby suppressing social interactions with familiar mice and contributing to social novelty preference. We further demonstrate how the maturation of CRH expression in ILA during the first 2 post-natal weeks enables the developmental shift from a preference for littermates in juveniles to a preference for novel mice in adults.


Assuntos
Hormônio Liberador da Corticotropina , Córtex Pré-Frontal , Animais , Camundongos , Neurônios , Transdução de Sinais , Percepção
2.
Development ; 147(18)2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32988974

RESUMO

The corpus callosum (CC) connects the cerebral hemispheres and is the major mammalian commissural tract. It facilitates bilateral sensory integration and higher cognitive functions, and is often affected in neurodevelopmental diseases. Here, we review the mechanisms that contribute to the development of CC circuits in animal models and humans. These species comparisons reveal several commonalities. First, there is an early period of massive axonal projection. Second, there is a postnatal temporal window, varying between species, in which early callosal projections are selectively refined. Third, sensory-derived activity influences axonal refinement. We also discuss how defects in CC formation can lead to mild or severe CC congenital malformations.


Assuntos
Corpo Caloso/fisiologia , Plasticidade Neuronal/fisiologia , Animais , Axônios/fisiologia , Humanos
3.
Rev Argent Microbiol ; 54(4): 309-313, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35644767

RESUMO

Health care workers (HCWs) are at high risk for SARS-CoV-2. In addition, pre-symptomatic or asymptomatic transmission accounts for around half of the cases. Saliva testing is an option to detect SARS-CoV-2 infection. To determine the performance of saliva samples for screening, HCWs were tested for SARS-CoV-2 by RT-PCR. Those with a positive result in saliva were tested by nasopharyngeal swabbing for viral RNA detection and blood collection to search for the presence of specific antibodies. In September-October 2020, 100 HCWs were enrolled and followed up. Six subjects (6%) tested positive in saliva. Of them, 5/6 were positive in a subsequent nasopharyngeal swab and 4/6 developed signs and symptoms compatible with COVID-19. Among the latter, 3 seroconverted while asymptomatic HCWs remained seronegative. Saliva screening was helpful for identifying SARS-CoV-2 infection in HCWs. This screening permitted rapid personnel isolation avoiding further transmission of the virus in the hospital setting.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , Saliva , Pessoal de Saúde , Nasofaringe
4.
J Med Virol ; 93(5): 3268-3272, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33527375

RESUMO

Current diagnostic standards involve severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detection in nasopharyngeal swabs (NPS), but saliva is an attractive and noninvasive option for diagnosis. The objectives were to determine the performance of saliva in comparison with NPS for detecting SARS-CoV-2 and to compare the optimized home brew reverse-transcription polymerase chain reaction (RT-PCR) with a commercial RT-PCR. Paired NPS and saliva specimens were prospectively collected and tested by RT-PCR from patients presenting at an emergency room with signs and symptoms compatible with coronavirus disease-2019. A total of 348 samples from 174 patients were tested by RT-PCR assays. Among 174 patients with symptoms, 63 (36%) were SARS-CoV-2 positive in NPS using the optimized home-brew PCR. Of these 63 patients, 61 (98%) were also positive in saliva. An additional positive SARS-CoV-2 saliva was detected in a patient with pneumonia. Kappa Cohen's coefficient agreement between NPS and saliva was 0.96 (95% confidence interval [CI], 0.90-0.99). Median Ct values in NPS versus saliva were 18.88 (interquartile range [IQR], 15.60-23.58; range, 11.97-38.10) versus 26.10 (IQR, 22.75-30.06; range, 13.78-39.22), respectively (p < .0001). The optimized home-brew RT-PCR demonstrated higher analytical and clinical sensitivity compared with the commercial RT-PCR assay. A high sensitivity (98%) and agreement (kappa 0.96) in saliva samples compared to NPS was demonstrated when using an optimized home-brew PCR even when the viral load in saliva was lower than in NPS. This noninvasive sample is easy to collect, requires less consumable and avoids discomfort to patients. Importantly, self-collection of saliva can diminish exposure to healthcare personnel.


Assuntos
COVID-19/diagnóstico , COVID-19/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , SARS-CoV-2/isolamento & purificação , Saliva/virologia , Manejo de Espécimes/métodos , Adulto , Idoso , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
5.
Rev Argent Microbiol ; 53(1): 20-26, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33162251

RESUMO

Lower acute respiratory infections (ARI) are a frequent cause of morbidity and mortality in infants, respiratory viruses being the major causative agents. The aim of this work was to determine the respiratory pathogen frequency, the clinical characteristics and the outcome in infants <2 months old hospitalized with ARI. A retrospective study was performed during a five-year period (2008-2011, 2014-2016). Respiratory viruses and atypical bacteria were studied using the FilmArray-Respiratory Panel. Demographic and clinical characteristics, hospitalization course and outcomes were evaluated. Of the 137 infants <2 months old hospitalized with ARI studied, a 94.9% positivity rate as determined in 117 infants with community-acquired infection and 20.0% in 20 infants who acquired the infection during their birth hospitalization in the neonatal intensive care units (NICU) (nosocomial ARI) (p<0.001). In infants with community-acquired infection, Respiratory syncytial virus (RSV) (52.1%) and Rhinovirus/Enterovirus (RV/EV) (41.0%) were the most frequent detected pathogens. Coinfections were determined in one quarter of the infants, RSV-RV/EV being the most frequent combination. In infants with nosocomial infection, RV/EV, RSV or Parainfluenza-3 were detected as single pathogens. Most infants with community-acquired infection presented lower ARI (81.2%) while most infants in the NICU had upper ARI (55.0%). The median length of stay (LOS) in infants with community-acquired ARI was 4 days (IQR: 2-6). Positive infants with nosocomial infection had longer median LOS (71 days [IQR:42-99]) compared to negative infants (58 days [IQR: 49-71]) (p=0.507). Respiratory viruses were detected as the major causative agents of community-acquired infection in hospitalized infants <2-months old, RSV and RV/EV being the most frequently detected. Although a low pathogen positivity rate was observed in infants with nosocomial infection, they may prolong the LOS.


Assuntos
Infecções Respiratórias , Vírus , Criança , Hospitalização , Humanos , Lactente , Recém-Nascido , Vírus Sinciciais Respiratórios , Infecções Respiratórias/epidemiologia , Estudos Retrospectivos
6.
Hum Mol Genet ; 24(14): 4037-48, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25882705

RESUMO

Retinitis pigmentosa (RP) is a group of progressive inherited retinal dystrophies that cause visual impairment as a result of photoreceptor cell death. RP is heterogeneous, both clinically and genetically making difficult to establish precise genotype-phenotype correlations. In a Spanish family with autosomal recessive RP (arRP), homozygosity mapping and whole-exome sequencing led to the identification of a homozygous mutation (c.358_359delGT; p.Ala122Leufs*2) in the ZNF408 gene. A screening performed in 217 additional unrelated families revealed another homozygous mutation (c.1621C>T; p.Arg541Cys) in an isolated RP case. ZNF408 encodes a transcription factor that harbors 10 predicted C2H2-type fingers thought to be implicated in DNA binding. To elucidate the ZNF408 role in the retina and the pathogenesis of these mutations we have performed different functional studies. By immunohistochemical analysis in healthy human retina, we identified that ZNF408 is expressed in both cone and rod photoreceptors, in a specific type of amacrine and ganglion cells, and in retinal blood vessels. ZNF408 revealed a cytoplasmic localization and a nuclear distribution in areas corresponding with the euchromatin fraction. Immunolocalization studies showed a partial mislocalization of the p.Arg541Cys mutant protein retaining part of the WT protein in the cytoplasm. Our study demonstrates that ZNF408, previously associated with Familial Exudative Vitreoretinopathy (FEVR), is a new gene causing arRP with vitreous condensations supporting the evidence that this protein plays additional functions into the human retina.


Assuntos
Proteínas de Ligação a DNA/genética , Exoma , Estudo de Associação Genômica Ampla , Retinose Pigmentar/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Animais , Células COS , Chlorocebus aethiops , Mapeamento Cromossômico , Proteínas de Ligação a DNA/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Homozigoto , Humanos , Dados de Sequência Molecular , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Linhagem , Retina/patologia , Células Fotorreceptoras Retinianas Cones/patologia , Células Fotorreceptoras Retinianas Bastonetes/patologia , Fatores de Transcrição/metabolismo
7.
Sci Adv ; 10(19): eadj9911, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38728406

RESUMO

During cerebral cortex development, excitatory pyramidal neurons (PNs) establish specific projection patterns while receiving inputs from GABAergic inhibitory interneurons (INs). Whether these inhibitory inputs can shape PNs' projection patterns is, however, unknown. While layer 4 (L4) PNs of the primary somatosensory (S1) cortex are all born as long-range callosal projection neurons (CPNs), most of them acquire local connectivity upon activity-dependent elimination of their interhemispheric axons during postnatal development. Here, we demonstrate that precise developmental regulation of inhibition is key for the retraction of S1L4 PNs' callosal projections. Ablation of somatostatin INs leads to premature inhibition from parvalbumin INs onto S1L4 PNs and prevents them from acquiring their barrel-restricted local connectivity pattern. As a result, adult S1L4 PNs retain interhemispheric projections responding to tactile stimuli, and the mice lose whisker-based texture discrimination. Overall, we show that temporally ordered IN activity during development is key to shaping local ipsilateral S1L4 PNs' projection pattern, which is required for fine somatosensory processing.


Assuntos
Neurônios GABAérgicos , Interneurônios , Córtex Somatossensorial , Animais , Interneurônios/metabolismo , Interneurônios/fisiologia , Interneurônios/citologia , Neurônios GABAérgicos/metabolismo , Neurônios GABAérgicos/fisiologia , Neurônios GABAérgicos/citologia , Córtex Somatossensorial/fisiologia , Córtex Somatossensorial/metabolismo , Córtex Somatossensorial/citologia , Camundongos , Células Piramidais/metabolismo , Células Piramidais/fisiologia , Parvalbuminas/metabolismo
8.
Viruses ; 16(3)2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38543797

RESUMO

Torque Teno Virus (TTV) is a nonpathogenic and ubiquitous ssDNA virus, a member of the Anelloviridae family. TTV has been postulated as a biomarker in transplant patients. This study aimed to determine the TTV species diversity and variability in renal transplant recipients and to associate species diversity with the corresponding TTV viral load. From 27 recipients, 30 plasma samples were selected. Viral load was determined using two real-time PCR assays, followed by RCA-NGS and ORF1 phylogenetic analysis. The TTV diversity was determined in all samples. Variability was determined in three patients with two sequential samples (pre- and post-transplantation). Most of the samples presented multiple TTV species, up to 15 different species were detected. In the pre-transplant samples (n = 12), the most prevalent species were TTV3 (75%) and TTV13 (75%), and the median number of species per sample was 5 (IQR: 4-7.5). TTV3 was also the most prevalent (56%) in the post-transplant samples (n = 18), and the median number of species was 2 (IQR: 1.8-5.5). No significant correlation between the number of species and viral load was found. The number and type of TTV species showed total variability over time. We report high TTV species diversity in Argentinian recipients, especially in pre-transplant period, with total intra-host variability. However, we found no significant correlation between this high diversity and TTV viral load.


Assuntos
Infecções por Vírus de DNA , Transplante de Rim , Torque teno virus , Humanos , Torque teno virus/genética , Transplante de Rim/efeitos adversos , Filogenia , Transplantados , Carga Viral , DNA Viral/genética
9.
Medicina (B Aires) ; 83(2): 185-189, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37094186

RESUMO

Asymptomatic infections with SARS-CoV-2 are associated with viral transmission and have a key role in the propagation of the pandemic. Understanding viral shedding during asymptomatic infections is critical. Unfortunately, data on asymptomatic SARS-CoV-2 infection in children is extremely limited. To determine the presence of viral viable shedding, we prospectively followed two healthy children of a family where both parents developed mild COVID-19 (April 2021). SARS-CoV-2 detection was made by RT-PCR and virus isolation by cell culture from saliva samples. Positive samples were sequenced to identify variants of SARS-CoV-2. Serum samples were evaluated to determine the presence of antibodies using a single enzyme-linked immunosorbent assay (ELISA, COVIDAR IgG). Both children were SARS-CoV-2 positive and asymptomatic. In addition, the virus grew in cell culture from saliva samples. Furthermore, one child showed viable SARS-CoV-2 for at least 17 days after the onset symptoms from his father. The recommended isolation period for asymptomatic contacts during the acquisition of data had been established for 10 days; however, this child remained with viable virus beyond that period. The positive samples from both children were consistent with B.1.1.28.1 lineage (Gamma). In both asymptomatic children, anti-Spike IgG was detected. Asymptomatic children may represent a source of infection that should not be underestimated during this pandemic.


Las infecciones asintomáticas por SARS-CoV-2 están asociadas a la transmisión viral y tienen un papel clave en la propagación de la pandemia. Comprender la excreción viral durante las infecciones asintomáticas es fundamental. Desafortunadamente, los datos sobre la infección asintomática por SARS-CoV-2 en niños son extremadamente limitados. Para determinar la presencia de excreción de virus viable, se siguió prospectivamente a dos niños sanos de una familia en la que ambos padres desarrollaron COVID-19 leve (abril 2021). La detección de SARS-CoV-2 se realizó por RT-PCR y el aislamiento del virus por cultivo celular a partir de muestras de saliva. Las muestras positivas se secuenciaron para identificar variantes de SARS-CoV-2. En las muestras de suero se determinó la presencia de anticuerpos utilizando un ensayo de ELISA (COVIDAR IgG). Ambos niños fueron positivos para SARS-CoV-2 y asintomáticos. Además, el virus creció en cultivos celulares a partir de muestras de saliva. Uno de los niños mantuvo SARS-CoV-2 viables durante al menos 17 días después de la aparición de los síntomas de su padre. El período de aislamiento recomendado para contactos asintomáticos durante la adquisición de datos se había establecido en 10 días, sin embargo, este niño permaneció con virus viable más allá de ese período. Las muestras positivas de estos niños correspondieron al linaje B.1.1.28.1 (Gamma). En ambos niños asintomáticos se detectó anticuerpos IgG anti-Spike. Concluimos que los niños asintomáticos pueden representar una fuente de infección que no debe subestimarse durante esta pandemia.


Assuntos
COVID-19 , SARS-CoV-2 , Criança , Humanos , Infecções Assintomáticas , Anticorpos Antivirais , Imunoglobulina G
10.
PLoS One ; 16(3): e0248191, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33684131

RESUMO

Human adenoviruses (HAdV) are one of the most frequent causes of respiratory infections around the world, causing mild to severe disease. In Argentina, many studies focused on the association of HAdV respiratory infection with severe disease and fatal outcomes leading to the discovery in 1984 of a genomic variant 7h associated with high fatality. Although several molecular studies reported the presence of at least 4 HAdV species (B, C, D and E) in Argentina, few sequences were available in the databases. In this study, sequences from the hexon gene region were obtained from 141 patients as a first approach to assess the genetic diversity of HAdVs circulating in Buenos Aires, Argentina. Phylogenetic analysis of these sequences and others recovered from public databases confirmed the circulation of the four above-mentioned species represented by 11 genotypes, with predominance in species B and C and shifts in their proportion in the studied period (2000 to 2018). The variants detected in Argentina, for most of the genotypes, were similar to those already described in other countries. However, uncommon lineages belonging to genotypes C2, C5 and E4 were detected, which might indicate the circulation of local variants and will deserve further studies of whole-genome sequences.


Assuntos
Infecções por Adenovirus Humanos/genética , Adenovírus Humanos/genética , Bases de Dados de Ácidos Nucleicos , Genótipo , Filogenia , Infecções Respiratórias/genética , Infecções por Adenovirus Humanos/epidemiologia , Adenovírus Humanos/isolamento & purificação , Argentina/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Análise de Sequência de DNA
11.
Infect Control Hosp Epidemiol ; 42(2): 142-148, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32900393

RESUMO

OBJECTIVE: To report a conjunctivitis outbreak in a neonatology intensive care unit (NICU) and determine the associated economic impact. DESIGN: Prospective observational study. SETTING: Centro de Educación Médica e Investigaciones Clínicas (CEMIC) University Hospital, a private, tertiary-care healthcare institution in Buenos Aires, Argentina. PARTICIPANTS: The study included 52 NICU neonates and 59 NICU-related healthcare workers (HCWs) from CEMIC hospital. METHODS: Neonates and HCWs were swabbed for real-time polymerase chain reaction (PCR) testing, viral culture, and typing by sequencing. Infection control measures, structural and logistic changes were implemented. Billing records were analyzed to determine costs. RESULTS: From January 30 to April 28, 2018, 52 neonates were hospitalized in the NICU. Among them, 14 of 52 (21%) had bilateral conjunctivitis with pseudomembranes. Symptomatic neonates and HCWs were HAdV-D8 positive. Ophthalmological symptoms had a median duration of 18 days (IQR, 13-24.5). PCR positivity and infectious range had a median duration of 18.5 days. As part of containment measures, the NICU and the high-risk pregnancy unit were closed to new patients. The NICU was divided into 2 areas for symptomatic and asymptomatic patients; a new room was assigned for the general nursery, and all deliveries from the high-risk pregnancy unit were redirected to other hospitals. The outbreak cost the hospital US$205,000: implementation of a new nursery room and extra salaries cost US$30,350 and estimated productivity loss during 1 month cost US$175,000. CONCLUSIONS: Laboratory diagnosis confirmed the cause of this outbreak as HAdV-D8. The immediate adoption and reinforcement of rigorous infection control measures limited the nosocomial viral spread. This outbreak represented a serious institutional problem, causing morbidity, significant economic loss, and absenteeism.


Assuntos
Conjuntivite , Infecção Hospitalar , Neonatologia , Adenoviridae , Conjuntivite/epidemiologia , Infecção Hospitalar/epidemiologia , Surtos de Doenças , Feminino , Genótipo , Humanos , Recém-Nascido , Controle de Infecções , Unidades de Terapia Intensiva Neonatal , Gravidez
13.
Ind Eng Chem Res ; 58(1): 296-305, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30774191

RESUMO

Biobased 2-butanol offers high potential as biofuel, but its toxicity toward microbial hosts calls for efficient techniques to alleviate product inhibition in fermentation processes. Aiming at the selective recovery of 2-butanol, the feasibility of a process combining in situ vacuum stripping followed by vapor adsorption has been assessed using mimicked fermentation media. The experimental vacuum stripping of model solutions and corn stover hydrolysate closely aligned with mass transfer model predictions. However, the presence of lignocellulosic impurities affected 2-butanol recovery yields resulting from vapor condensation, which decreased from 96 wt % in model solutions to 40 wt % using hydrolysate. For the selective recovery of 2-butanol from a vapor mixture enriched in water and carbon dioxide, silicalite materials were the most efficient, particularly at low alcohol partial pressures. Integrating in situ vacuum stripping with vapor adsorption using HiSiv3000 proved useful to effectively concentrate 2-butanol above its azeotropic composition (>68 wt %), facilitating further product purification.

14.
Medicina (B.Aires) ; 83(2): 185-189, jun. 2023. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1448620

RESUMO

Abstract Asymptomatic infections with SARS-CoV-2 are associ ated with viral transmission and have a key role in the propagation of the pandemic. Understanding viral shed ding during asymptomatic infections is critical. Unfor tunately, data on asymptomatic SARS-CoV-2 infection in children is extremely limited. To determine the presence of viral viable shedding, we prospectively followed two healthy children of a family where both parents devel oped mild COVID-19 (April 2021). SARS-CoV-2 detection was made by RT-PCR and virus isolation by cell culture from saliva samples. Positive samples were sequenced to identify variants of SARS-CoV-2. Serum samples were evaluated to determine the presence of antibodies using a single enzyme-linked immunosorbent assay (ELISA, COVIDAR IgG). Both children were SARS-CoV-2 positive and asymptomatic. In addition, the virus grew in cell cul ture from saliva samples. Furthermore, one child showed viable SARS-CoV-2 for at least 17 days after the onset symptoms from his father. The recommended isolation period for asymptomatic contacts during the acquisition of data had been established for 10 days; however, this child remained with viable virus beyond that period. The positive samples from both children were consistent with B.1.1.28.1 lineage (Gamma). In both asymptomatic children, anti-Spike IgG was detected. Asymptomatic children may represent a source of infection that should not be underestimated during this pandemic.


Resumen Las infecciones asintomáticas por SARS-CoV-2 están asociadas a la transmisión viral y tienen un papel cla ve en la propagación de la pandemia. Comprender la excreción viral durante las infecciones asintomáticas es fundamental. Desafortunadamente, los datos sobre la infección asintomática por SARS-CoV-2 en niños son extremadamente limitados. Para determinar la presencia de excreción de virus viable, se siguió prospectivamente a dos niños sanos de una familia en la que ambos padres desarrollaron COVID-19 leve (abril 2021). La detección de SARS-CoV-2 se realizó por RT-PCR y el aislamiento del virus por cultivo celular a partir de muestras de saliva. Las muestras positivas se secuenciaron para identificar variantes de SARS-CoV-2. En las muestras de suero se determinó la presencia de anticuerpos utilizando un ensayo de ELISA (COVIDAR IgG). Ambos niños fueron positivos para SARS-CoV-2 y asintomáticos. Además, el virus creció en cultivos celulares a partir de muestras de saliva. Uno de los niños mantuvo SARS-CoV-2 via bles durante al menos 17 días después de la aparición de los síntomas de su padre. El período de aislamiento recomendado para contactos asintomáticos durante la adquisición de datos se había establecido en 10 días, sin embargo, este niño permaneció con virus viable más allá de ese período. Las muestras positivas de estos niños correspondieron al linaje B.1.1.28.1 (Gamma). En ambos niños asintomáticos se detectó anticuerpos IgG anti-Spike. Concluimos que los niños asintomáticos pueden representar una fuente de infección que no debe subestimarse durante esta pandemia.

15.
Nat Commun ; 9(1): 473, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29382840

RESUMO

The original version of this Article contained an error in the spelling of the author Álvaro Sebastián-Serrano, which was incorrectly given as Álvaro Sebastián Serrano. This has now been corrected in both the PDF and HTML versions of the Article.

16.
Biotechnol J ; 12(7)2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28256799

RESUMO

The conceptual design of a bio-based process for 2-butanol production is presented for the first time. Considering a hypothetical efficient producing strain, a vacuum fermentation is proposed to alleviate product toxicity, but the main challenge is the energy-efficient product recovery from the vapor. Three downstream scenarios were examined for this purpose: 1) multi-stage vapor recompression; 2) temperature swing adsorption; and 3) vapor absorption. The processes were simulated using Aspen Plus, considering a production capacity of 101 kton/yr. Process optimization was performed targeting the minimum selling price of 2-butanol. The feasibility of the different configurations was analyzed based on the global energy requirements and capital expenditure. The use of integrated adsorption and absorption minimized the energy duty required for azeotrope purification, which represents 11% of the total operational expenditure in Scenario 1. The minimum selling price of 2-butanol as commodity chemical was estimated as 1.05 $/kg, 1.21 $/kg, and 1.03 $/kg regarding the fermentation integrated with downstream scenarios 1), 2), and 3), respectively. Significant savings in 2-butanol production could be achieved in the suggested integrated configurations if more efficient microbial strains were engineered, and more selective adsorption and absorption materials were found for product recovery.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Butanóis/metabolismo , Fermentação , Engenharia de Proteínas , Vácuo
17.
Nat Commun ; 8(1): 2275, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29273751

RESUMO

Excitotoxicity, a critical process in neurodegeneration, induces oxidative stress and neuronal death through mechanisms largely unknown. Since oxidative stress activates protein kinase D1 (PKD1) in tumor cells, we investigated the effect of excitotoxicity on neuronal PKD1 activity. Unexpectedly, we find that excitotoxicity provokes an early inactivation of PKD1 through a dephosphorylation-dependent mechanism mediated by protein phosphatase-1 (PP1) and dual specificity phosphatase-1 (DUSP1). This step turns off the IKK/NF-κB/SOD2 antioxidant pathway. Neuronal PKD1 inactivation by pharmacological inhibition or lentiviral silencing in vitro, or by genetic inactivation in neurons in vivo, strongly enhances excitotoxic neuronal death. In contrast, expression of an active dephosphorylation-resistant PKD1 mutant potentiates the IKK/NF-κB/SOD2 oxidative stress detoxification pathway and confers neuroprotection from in vitro and in vivo excitotoxicity. Our results indicate that PKD1 inactivation underlies excitotoxicity-induced neuronal death and suggest that PKD1 inactivation may be critical for the accumulation of oxidation-induced neuronal damage during aging and in neurodegenerative disorders.


Assuntos
Morte Celular , Neurônios/metabolismo , Neuroproteção , Estresse Oxidativo , Proteína Quinase C/metabolismo , Animais , Fosfatase 1 de Especificidade Dupla/metabolismo , Quinase I-kappa B/metabolismo , Técnicas In Vitro , Camundongos , Camundongos Knockout , NF-kappa B/metabolismo , Fosforilação , Proteína Fosfatase 1/metabolismo , Transdução de Sinais , Superóxido Dismutase/metabolismo
18.
Influenza Other Respir Viruses ; 7(5): 623-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23216743

RESUMO

Human Rhinovirus (HRV) classification is an evolving process. New genotypes have been described within HRV-A and HRV-C species, but only one has been accepted related to HRV-B. From 2003 to 2010, a total of 3987 nasopharyngeal aspirate samples were taken from pediatric patients admitted to the Severo Ochoa Hospital in Madrid (Spain). After viral analysis, 949 (23.8%) tested positive to HRV. A random selection of 397 (42%) positive samples showed that 39 (9.8%) were HRV-B. The sequencing of partial VP4/VP2 coding region revealed the spread of 13 of 25 defined HRV-B serotypes and three putative new genotypes. Such results remark the high diversity of HRV-B.


Assuntos
Infecções por Picornaviridae/virologia , Infecções Respiratórias/virologia , Rhinovirus/genética , Rhinovirus/isolamento & purificação , Adolescente , Criança , Criança Hospitalizada , Pré-Escolar , Feminino , Genótipo , Humanos , Lactente , Masculino , Dados de Sequência Molecular , Filogenia , Infecções por Picornaviridae/epidemiologia , Infecções Respiratórias/epidemiologia , Rhinovirus/classificação , Espanha
19.
Vector Borne Zoonotic Dis ; 12(3): 223-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22022811

RESUMO

We report the characterization of three novel flaviviruses isolated in Spain. Marisma Mosquito virus, a novel mosquito borne virus, was isolated from Ochlerotatus caspius mosquitoes; Spanish Ochlerotatus flavivirus and Spanish Culex flavivirus, two novel insect flaviviruses, were isolated from Oc. caspius and Culex pipiens, respectively. During this investigation, we designed a sensitive RT-nested polymerase chain reaction method that amplifies a 1019bp fragment of the flavivirus NS5 gene and could be directly used in clinical or environmental samples for flavivirus characterization and surveillance. Analysis of the sequence generated from that amplicon contains enough phylogenetic information for proper taxonomic studies. Moreover, the use of this tool allowed the detection of additional flavivirus DNA forms in Culex, Culiseta, and Ochlerotatus mosquitoes.


Assuntos
Culicidae/virologia , Flavivirus/classificação , Insetos Vetores/virologia , Filogenia , Proteínas não Estruturais Virais/genética , Animais , Sequência de Bases , Culex/virologia , Feminino , Flavivirus/genética , Flavivirus/isolamento & purificação , Infecções por Flavivirus/transmissão , Masculino , Dados de Sequência Molecular , Ochlerotatus/virologia , Reação em Cadeia da Polimerase , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Espanha/epidemiologia
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