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1.
Bol Med Hosp Infant Mex ; 81(2): 90-96, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38768514

RESUMO

BACKGROUND: After the SARS-CoV-2 pandemic, there has been an increase in hospitalization for lower respiratory infection secondary to respiratory syncytial virus (RSV), with greater complications. Associated extrapulmonary alterations, biventricular dysfunction, acute kidney injury, among others, have been found. The objective of this study was to analize the evolution and complications in hospitalized children with lower respiratory infection secondary to RSV after COVID-19 pandemic. METHODS: All pediatric patients under 2 years of age admitted to the emergency department with RSV infection were included. Clinical characteristics, need for supplemental oxygen, use of amines, renal angina index, and requirement for renal replacement therapy were analyzed. Lung ultrasound was performed upon admission. Statistical analysis was carried out for the quantitative variables by means of mean and standard deviation, and qualitative variables by frequency and percentage. Differences in the distribution were evaluated with Fisher's exact distribution. RESULTS: 45 patients with RSV infection were identified, 26.7% required invasive mechanical ventilation and 11.1% requiered peritoneal dialysis. Fatality was observed in four cases, three of these younger than 12 months with a LUS score > 7; contrasts with 90.2% of survivors with a score < 7 (p = 0.0004). CONCLUSIONS: An increase in the incidence of bronchiolitis after pandemic was observed, with more than half having moderate to severe symptoms and requiring supplemental oxygen support in all patients upon admission. Acute kidney injury is the most common extrapulmonary manifestation.


INTRODUCCIÓN: Posterior a la pandemia por SARS-CoV-2 se ha observado un incremento en la hospitalización por virus respiratorio sincitial (VRS), con mayores complicaciones. Se han encontrado alteraciones extrapulmonares asociadas, disfunción biventricular y lesión renal aguda, entre otras. El objetivo de este estudio fue analizar la evolución y las complicaciones en niños hospitalizados con enfermedad respiratoria de vías bajas secundaria a infección por VRS tras la pandemia de COVID-19. MÉTODOS: Se incluyeron todos los menores de 2 años que ingresaron al servicio de urgencias con infección por VRS. Se analizaron las características clínicas, la necesidad de oxígeno suplementario, el uso de aminas, el índice de angina renal y el requerimiento de terapia de sustitución renal. Se realizó ecografía pulmonar al ingreso. En el análisis estadístico, para las variables cuantitativas se determinaron la media y la desviación estándar, y para las variables cualitativas la frecuencia y el porcentaje. Se evaluaron las diferencias de la distribución con la prueba exacta de Fisher. RESULTADOS: Hubo 45 pacientes con infección por VRS. El 26.7% requirieron ventilación mecánica invasiva y el 11.1% diálisis peritoneal. La letalidad fue de cuatro casos, tres de ellos menores de 12 meses con puntuación de LUS > 7; esto contrasta con el 90.2% de los sobrevivientes con puntaje < 7 (p = 0.0004). CONCLUSIONES: Se observó un aumento en la incidencia de bronquiolitis tras la pandemia, en más de la mitad de los casos con cuadros de moderados a graves, y todos requirieron oxígeno suplementario al ingreso. La lesión renal aguda fue la manifestación extrapulmonar más frecuente.


Assuntos
COVID-19 , Hospitalização , Respiração Artificial , Infecções por Vírus Respiratório Sincicial , Índice de Gravidade de Doença , Humanos , Infecções por Vírus Respiratório Sincicial/epidemiologia , COVID-19/epidemiologia , COVID-19/complicações , Lactente , Masculino , Feminino , Hospitalização/estatística & dados numéricos , Recém-Nascido , Diálise Peritoneal , Serviço Hospitalar de Emergência , Estudos Retrospectivos
2.
Microbiol Mol Biol Rev ; 88(2): e0015823, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38551349

RESUMO

SUMMARYThe metabolic conditions that prevail during bacterial growth have evolved with the faithful operation of repair systems that recognize and eliminate DNA lesions caused by intracellular and exogenous agents. This idea is supported by the low rate of spontaneous mutations (10-9) that occur in replicating cells, maintaining genome integrity. In contrast, when growth and/or replication cease, bacteria frequently process DNA lesions in an error-prone manner. DNA repairs provide cells with the tools needed for maintaining homeostasis during stressful conditions and depend on the developmental context in which repair events occur. Thus, different physiological scenarios can be anticipated. In nutritionally stressed bacteria, different components of the base excision repair pathway may process damaged DNA in an error-prone approach, promoting genetic variability. Interestingly, suppressing the mismatch repair machinery and activating specific DNA glycosylases promote stationary-phase mutations. Current evidence also suggests that in resting cells, coupling repair processes to actively transcribed genes may promote multiple genetic transactions that are advantageous for stressed cells. DNA repair during sporulation is of interest as a model to understand how transcriptional processes influence the formation of mutations in conditions where replication is halted. Current reports indicate that transcriptional coupling repair-dependent and -independent processes operate in differentiating cells to process spontaneous and induced DNA damage and that error-prone synthesis of DNA is involved in these events. These and other noncanonical ways of DNA repair that contribute to mutagenesis, survival, and evolution are reviewed in this manuscript.


Assuntos
Bacillus subtilis , Reparo do DNA , Mutagênese , Reparo do DNA/genética , Bacillus subtilis/genética , Bacillus subtilis/fisiologia , Estresse Fisiológico/genética , Dano ao DNA , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Replicação do DNA , DNA Bacteriano/genética , Esporos Bacterianos/genética , Esporos Bacterianos/crescimento & desenvolvimento
3.
Microbiol Spectr ; 11(4): e0043223, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37284752

RESUMO

A green fluorescent protein (GFP)-based whole-cell biosensor (WCB-GFP) for monitoring arsenic (As) was developed in Bacillus subtilis. To this end, we designed a reporter gene fusion carrying the gfpmut3a gene under the control of the promoter/operator region of the arsenic operon (Pars::gfpmut3a) in the extrachromosomal plasmid pAD123. This construct was transformed into B. subtilis 168, and the resultant strain was used as a whole-cell biosensor (BsWCB-GFP) for the detection of As. The BsWCB-GFP was specifically activated by inorganic As(III) and As(V), but not by dimethylarsinic acid [DMA(V)], and exhibited high tolerance to the noxious effects of arsenic. Accordingly, after 12 h exposure, B. subtilis cells carrying the Pars::gfpmut3a fusion exhibited 50 and 90% lethal doses (LD50 and LD90) to As(III) of 0.89 mM and As 1.71 mM, respectively. Notably, dormant spores from the BsWCB-GFP were able to report the presence of As(III) in a concentration range from 0.1 to 1,000 µM 4 h after the onset of germination. In summary, the specificity and high sensitivity for As, as well as its ability to proliferate under concentrations of the metal that are considered toxic in water and soil, makes the B. subtilis biosensor developed here a potentially important tool for monitoring environmental samples contaminated with this pollutant. IMPORTANCE Arsenic (As) contamination of groundwater is associated with serious worldwide health risks. Detection of this pollutant at concentrations that are established as permissible for water consumption by WHO is a matter of significant interest. Here, we report the generation of a whole-cell biosensor for As detection in the Gram-positive spore former B. subtilis. This biosensor reports the presence of inorganic As, activating the expression of the green fluorescent protein (GFP) under the control of the promoter/operator of the ars operon. The biosensor can proliferate under concentrations of As(III) that are considered toxic in water and soil and detect this ion at concentrations as low as 0.1 µM. Of note, spores of the Pars-GFP biosensor exhibited the ability to detect As(III) following germination and outgrowth. Therefore, this novel tool has the potential to be directly applied to monitor As contamination in environmental samples.


Assuntos
Arsênio , Técnicas Biossensoriais , Poluentes Ambientais , Bacillus subtilis/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Arsênio/metabolismo , Esporos Bacterianos/genética , Esporos Bacterianos/química , Água/metabolismo , Poluentes Ambientais/metabolismo
4.
Arch Suicide Res ; : 1-12, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37204142

RESUMO

OBJECTIVE: The main aim of the current study was to investigate whether SKA2 gene expression in the postmortem brain of rs7208505 genotype are altered in suicide victims from a Mexican population. METHODS: In this study, we report a genetic analysis of expression levels of the SKA2 gene in the prefrontal cortex of the postmortem brain of suicidal subjects (n = 22) compared to subjects who died of causes other than suicide (n = 22) in a Mexican population using RT-qPCR assays. Additionally, we genotyped the rs7208505 polymorphism in suicide victims (n = 98) and controls (n = 88) and we evaluate the association of genotypes for the SNP rs7208505 with expression level of SKA2. RESULTS: The results showed that the expression of the SKA2 gene was significantly higher in suicide victims compared to control subjects (p = 0.044). Interestingly, we observed a greater proportion of allele A of the rs7208505 in suicide victims than controls. Even though there was no association between the SNP with suicide in the study population we found a significative association of the expression level from SKA2 with the allele A of the rs7208505 and suicide. CONCLUSION: The evidence suggests that the expression of SKA2 in the prefrontal cortex may be a critical factor in the etiology of suicidal behavior.


HighlightsSuicide victims have a higher level of SKA2 gene expression in the brain's prefrontal cortex than control subjects.The SKA2 rs7208505 is not associated with suicide in the Mexican population studied.Allele frequencies for G are higher than allele frequencies for A in our study population.The allele A of the rs7208505 affects the expression values of the SKA2 gene.

5.
Micromachines (Basel) ; 13(12)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36557532

RESUMO

This research presents the design of time-modulated antenna arrays with UWB performance. The antenna arrays consider a linear topology with eight UWB disk-notch patch antennas. The technological problem is to find out the optimum antenna positions and/or time sequences to reduce the side lobes and the sidebands in all of the UWB frequency ranges. The design process is formulated as a bacterial foraging optimization. The results show that the uniform array generates a better SLL performance whereas the non-uniform array obtains a wider bandwidth. The uniform array obtains an SLL < −20 dB from 3.37 GHz to 4.8 GHz and the non-uniform array generates an SLL < −7 dB from 2.97 GHz to 5.26 GHz. The sideband levels are very similar for both cases with a value of around −17 dB.

6.
Methods Mol Biol ; 2527: 203-221, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35951193

RESUMO

Somatic embryogenesis (SE) is a process that allows formation of embryos from somatic cells; this biological process has different stages that first require micropropagation and conditioning of explant, and then induction, multiplication, development, and germination of somatic embryos (SoE), to obtain seedlings that will be acclimatized and grown in a greenhouse to further be cultivated in the field. Inorganic compounds are supplemented by macro- and micronutrients that can conform different culture media, and with other compounds such as a carbon source, vitamins, and plant growth regulators (PGRs), will direct the fate of the plant cells to obtain SoE that will regenerate into plants. The concentration of these inorganic compounds must be optimized, since at very high concentrations they can cause toxicity and at low concentrations they may not induce the desired response. The objective of this chapter is to describe the most significant advances in the use of inorganic elements during the different stages of SE, starting with the description of the most used basal media and later describing the use of the main studied mineral elements during establishment of SE.


Assuntos
Reguladores de Crescimento de Plantas , Técnicas de Embriogênese Somática de Plantas , Meios de Cultura , Desenvolvimento Embrionário , Germinação
7.
Brain Res Bull ; 177: 172-180, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34624462

RESUMO

Environmental enrichment (EE) has been proven to reduce drug seeking and the development of addiction-related behaviors in rodent models, but the effects of EE on natural reward acquisition in the form of sweet beverages are poorly understood. Accumulating evidence shows that the intake of sugar, the main ingredient of sweet beverages, alters the dopaminergic system, leading to addiction-related physiological and molecular changes. Sugar in sweet beverages has been replaced with natural sweeteners, such as stevia extract, which has greater sweetener potential but no energy content. Our research group found that sucralose consumption increased the expression of ΔFosB in reward-related nuclei, suggesting activation of the dopaminergic system. The present study assessed the effects of EE on stevia consumption and the expression of ΔFosB in the nucleus accumbens, caudate putamen, and prefrontal cortex. Sixteen male Wistar rats, 21 days old, were randomly assigned to an EE group (n = 8) or standard environment (SE) group (n = 8) and reared for 30 days. On postnatal day 52 (PND52), the brains of four animals in each housing condition were extracted to determine basal ΔFosB levels. Stevia consumption with intermittent access and ΔFosB immunoreactivity were measured for 21 days in the remainder of the rats. Compared with SE animals, EE animals exhibited a reduction of stevia consumption and alterations of ΔFosB immunoreactivity in the reward system. These results indicate that EE reduces stevia consumption and the stevia-induced ΔFosB expression, suggesting addiction-related changes in dopaminergic nuclei, which may be interpreted as a neuroprotective effect.


Assuntos
Stevia , Animais , Masculino , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Wistar , Recompensa , Stevia/metabolismo , Edulcorantes
8.
Rev. biol. trop ; 69(3)sept. 2021.
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1387668

RESUMO

Abstract Introduction: Although olive ridley sea turtle (Lepidochelys olivacea) are the most abundant sea turtles in the world, quantitative information is scarce and unevenly distributed among regions. There are many management and conservation programs for this species, and assessments are necessary to identify nesting trends and effectively manage current conservation programs. PROTORMAR-UAS is a Research and Conservation program for the olive ridley turtle created by the Autonomous University of Sinaloa, Mexico. The program utilizes two biological stations: Santuario Playa Ceuta (SPC) and Playa Caimanero (PC). Objective: To evaluate the nesting trend of olive ridley turtles on two beaches in Northwestern Mexico and to predict prospective nesting trends for the next 30 years. Methods: Using annual nesting data collected over 40 years at SPC (1976-2016) and 30 years at PC (1986-2016), we evaluated nesting trends, hatching success, predation and poaching of olive ridley turtles on the two beaches in Northwestern Mexico. Then, prospective nesting estimates for the next 30 years were calculated predictive time series model. Results: A positive and significant correlation was identified between the number of annual nests and time for both beaches (rho = 0.850, P ≤ 0.01 for SPC; rho = 0.677, P ≤ 0.01 for PC); the average hatching success rates were 65.09 at SPC and 60.72 % at PC. The predictive time-series model indicated that the numbers of nests will continue to increase through 2045, increasing three-fold at SPC and six-fold at PC with respect to the last year of monitoring. Conclusions: There was a clear positive trend in the number of olive ridley sea turtle nests at both sites, which is consistent with trends found in other recent studies from the region. Therefore, we suggest that PC be designated a legally protected nesting area since it is located within the latitudinal limits of olive ridley nesting and given the need for resources for camp operation considering increased nesting and current problems with predation and poaching. Because in Mexico operating a nesting beach without any protection status implies not having a budget for its management.


Resumen Introducción: A pesar de que las tortugas golfinas (Lepidochelys olivacea) son las tortugas marinas más abundantes del mundo, su información cuantitativa disponible es escasa y se encuentra distribuida de manera desigual entre regiones. Existen muchos programas de manejo y conservación para esta especie, y sus evaluaciones son necesarias para identificar tendencias de anidación y poder manejar de manera efectiva los programas de conservación actuales. PROTORMAR-UAS es un programa de Investigación y Conservación de la tortuga golfina creado por la Universidad Autónoma de Sinaloa, México. El Programa cuenta con dos estaciones biológicas: Santuario de Playa Ceuta (SPC) y Playa Caimanero (PC). Objetivo: Evaluar la tendencia de anidación de la tortuga golfina en dos playas del noroeste de México y predecir las tendencias prospectivas de anidación para los próximos 30 años. Métodos: A partir de los datos de registros anuales de anidación de 40 años para SPC (1976-2016) y 30 años para PC (1986-2016), evaluamos las tendencias de anidación, el éxito de la eclosión y los problemas de depredación y saqueo de nidos de la tortuga golfina en las dos playas del noroeste de México. Posteriormente, se calcularon las estimaciones prospectivas de anidación para los próximos 30 años usando un modelo predictivo de series de tiempo. Resultados: Se identificó una correlación positiva y significativa entre el registro anual de nidos y el tiempo de estudio para ambas playas (rho = 0.850, P ≤ 0.01 para SPC; rho = 0.677 y P ≤ 0.01 para PC); así como el éxito de eclosión promedio de 65.09 para SPC y de 60.72 % para PC. El modelo predictivo de series de tiempo indicó que las anidaciones continuarán aumentando para el 2045, tres veces para SPC y seis para PC, con respecto al último año de monitoreo. Conclusiones: Hay una clara tendencia positiva de anidación de la tortuga golfina en ambos sitios, lo cual es consistente con la tendencia observada en otros estudios recientes de la región. Por lo tanto, sugerimos incluir a PC como un área de anidación legalmente protegida, la cual se ubica en los límites latitudinales de anidación de la tortuga golfina, dada la necesidad de contar con recursos disponibles para la operación del campamento ante el aumento de anidaciones y de problemas de depredación y saqueo. Porque en México operar una playa de anidación sin ningún estatus de protección implica no tener presupuesto para su manejo.


Assuntos
Animais , Reprodução , Tartarugas , Controle Biológico por Conservação , México
9.
Arch Microbiol ; 203(6): 3317-3330, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33864113

RESUMO

The continual increase in resistance to antibacterial drugs has become a major public health problem, and their indiscriminate use in agriculture, aquaculture, and the treatment of human and animal diseases has severely contributed to the occurrence and spread of multidrug resistance genes. This study phylogenetically characterized multidrug-resistant bacteria isolated from seafood cocktails. Seafood cocktail dishes from 20 establishments on public roads were sampled. Samples were grown on TCBS agar and blood agar. Forty colonies with different macro- and microscopic characteristics were isolated. The 16S rRNA gene V4 and V6 hypervariable regions were amplified, sequenced and phylogenetically analyzed. Antibacterial drug resistance was determined by disk diffusion assay. Isolated bacteria were identical to species of the genera Enterococcus, Proteus, Vibrio, Staphylococcus, Lactococcus, Vagococcus, Micrococcus, Acinetobacter, Enterobacter, and Brevibacterium, with 75-100% presenting resistance or intermediate resistance to dicloxacillin, ampicillin, and penicillin; 50-70% to cephalosporins; 30-67.5% to amikacin, netilmicin and gentamicin; 40% to nitrofurantoin and other antibacterial drugs; 25% to chloramphenicol; and 2.5% to trimethoprim with sulfamethoxazole. In general, 80% of the bacteria showed resistance to multiple antibiotics. The high degree of bacterial resistance to antibacterial drugs indicates that their use in producing raw material for marine foods requires established guidelines and the implementation of good practices.


Assuntos
Bactérias/isolamento & purificação , Farmacorresistência Bacteriana Múltipla , Alimentos Marinhos/microbiologia , Bactérias/classificação , Bactérias/genética , Filogenia
10.
Sci Rep ; 11(1): 2513, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33510358

RESUMO

During sporulation Bacillus subtilis Mfd couples transcription to nucleotide excision repair (NER) to eliminate DNA distorting lesions. Here, we report a significant decline in sporulation following Mfd disruption, which was manifested in the absence of external DNA-damage suggesting that spontaneous lesions activate the function of Mfd for an efficient sporogenesis. Accordingly, a dramatic decline in sporulation efficiency took place in a B. subtilis strain lacking Mfd and the repair/prevention guanine oxidized (GO) system (hereafter, the ∆GO system), composed by YtkD, MutM and MutY. Furthermore, the simultaneous absence of Mfd and the GO system, (i) sensitized sporulating cells to H2O2, and (ii) elicited spontaneous and oxygen radical-induced rifampin-resistance (Rifr) mutagenesis. Epifluorescence (EF), confocal and transmission electron (TEM) microscopy analyses, showed a decreased ability of ∆GO ∆mfd strain to sporulate and to develop the typical morphologies of sporulating cells. Remarkably, disruption of sda, sirA and disA partially, restored the sporulation efficiency of the strain deficient for Mfd and the ∆GO system; complete restoration occurred in the RecA- background. Overall, our results unveil a novel Mfd mechanism of transcription-coupled-repair (TCR) elicited by 8-OxoG which converges in the activation of a RecA-dependent checkpoint event that control the onset of sporulation in B. subtilis.


Assuntos
Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Reparo do DNA , Guanina/análogos & derivados , Recombinases Rec A/metabolismo , Transcrição Gênica , Bacillus subtilis/ultraestrutura , Dano ao DNA , Regulação Bacteriana da Expressão Gênica , Guanina/metabolismo , Mutação , Espécies Reativas de Oxigênio , Esporos Bacterianos
11.
Appl Environ Microbiol ; 86(20)2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32801174

RESUMO

Cr(VI) is mutagenic and teratogenic and considered an environmental pollutant of increasing concern. The use of microbial enzymes that convert this ion into its less toxic reduced insoluble form, Cr(III), represents a valuable bioremediation strategy. In this study, we examined the Bacillus subtilis YhdA enzyme, which belongs to the family of NADPH-dependent flavin mononucleotide oxide reductases and possesses azo-reductase activity as a factor that upon overexpression confers protection on B. subtilis from the cytotoxic effects promoted by Cr(VI) and counteracts the mutagenic effects of the reactive oxygen species (ROS)-promoted lesion 8-OxoG. Further, our in vitro assays unveiled catalytic and biochemical properties of biotechnological relevance in YhdA; a pure recombinant His10-YhdA protein efficiently catalyzed the reduction of Cr(VI) employing NADPH as a cofactor. The activity of the pure oxidoreductase YhdA was optimal at 30°C and at pH 7.5 and displayed Km and Vmax values of 7.26 mM and 26.8 µmol·min-1·mg-1 for Cr(VI), respectively. Therefore, YhdA can be used for efficient bioremediation of Cr(VI) and counteracts the cytotoxic and genotoxic effects of oxygen radicals induced by intracellular factors and those generated during reduction of hexavalent chromium.IMPORTANCE Here, we report that the bacterial flavin mononucleotide/NADPH-dependent oxidoreductase YhdA, widely distributed among Gram-positive bacilli, conferred protection to cells from the cytotoxic effects of Cr(VI) and prevented the hypermutagenesis exhibited by a MutT/MutM/MutY-deficient strain. Additionally, a purified recombinant His10-YhdA protein displayed a strong NADPH-dependent chromate reductase activity. Therefore, we postulate that in bacterial cells, YhdA counteracts the cytotoxic and genotoxic effects of intracellular and extracellular inducers of oxygen radicals, including those caused by hexavalent chromium.


Assuntos
Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/fisiologia , Proteínas de Bactérias/metabolismo , Cromo/toxicidade , FMN Redutase/metabolismo , Bacillus subtilis/enzimologia , Bacillus subtilis/genética , Proteínas de Bactérias/química , FMN Redutase/química
13.
Neuroreport ; 30(7): 510-515, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30896675

RESUMO

Socialization is an adaptive behavior during the early stages of life because it helps young animals become independent and determines healthy adult social behavior. Therefore, it is probable that the brain areas involved in the processing of social stimuli are more sensitive to social novelty during early life stages. To test this hypothesis, four groups of young male rats were exposed to different socioenvironmental stimuli; nonsocial physical novelty, social familiarity, social novelty, and a control group which received no stimulation. After stimuli exposure, brains were fixed and cut in coronal sections for c-Fos immunohistochemistry. The number of c-Fos-immunoreactive (c-Fos-ir) neurons in the paraventricular nucleus and supraoptic nucleus, the main producers of oxytocin and vasopressin, was compared, as well as in the nucleus accumbens and ventral pallidum, the main areas involved in reinforced behavior. A significantly higher number of c-Fos-ir neurons were found in animals exposed to social novelty in all areas, except in the supraoptic nucleus. In particular, the increase in c-Fos-ir in the paraventricular nucleus seems to be selective in response to social novelty, while the increase of c-Fos-ir in the nucleus accumbens and ventral pallidum suggests that social novelty during youth is a highly rewarding stimulus compared with social familiarity and nonsocial physical novelty.


Assuntos
Comportamento Animal/fisiologia , Hipotálamo/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Comportamento Social , Animais , Imuno-Histoquímica , Masculino , Ratos , Ratos Wistar , Recompensa
14.
PLoS One ; 14(2): e0211653, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30726292

RESUMO

DNA deamination generates base transitions and apurinic/apyrimidinic (AP)-sites which are potentially genotoxic and cytotoxic. In Bacillus subtilis uracil can be removed from DNA by the uracil DNA-glycosylase through the base excision repair pathway. Genetic evidence suggests that B. subtilis YwqL, a homolog of Endonuclease-V (EndoV), acts on a wider spectrum of deaminated bases but the factors that complete this pathway have remained elusive. Here, we report that a purified His6-YwqL (hereafter BsEndoV) protein had in vitro endonuclease activity against double-stranded DNAs containing a single uracil (U), hypoxanthine (Hx), xanthine (X) or an AP site. Interestingly, while BsEndoV catalyzed a single strand break at the second phosphodiester bond towards the 3'-end of the U and AP lesions, there was an additional cleavage of the phosphodiester bond preceding the Hx and X lesions. Remarkably, the repair event initiated by BsEndoV on Hx and X, was completed by a recombinant B. subtilis His6-DNA polymerase A (BsPolA), but not on BsEndoV-processed U and AP lesions. For the latter lesions a second excision event performed by a recombinant B. subtilis His6-ExoA (BsExoA) was necessary before completion of their repair by BsPolA. These results suggest the existence of a novel alternative excision repair pathway in B. subtilis that counteracts the genotoxic effects of base deamination. The presence of this novel pathway in vivo in B. subtilis was also supported by analysis of effects of single or multiple deletions of exoA, endoV and polA on spontaneous mutations in growing cells, and the sensitivity of growing wild-type and mutant cells to a DNA deaminating agent.


Assuntos
Bacillus subtilis/metabolismo , Proteínas de Bactérias/metabolismo , DNA Polimerase I/metabolismo , Reparo do DNA , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Desoxirribonuclease (Dímero de Pirimidina)/metabolismo , Bacillus subtilis/genética , Proteínas de Bactérias/genética , DNA Polimerase I/genética , Desaminação , Desoxirribonuclease (Dímero de Pirimidina)/genética , Mutagênese , Proteínas Recombinantes
15.
Blood Transfus ; 16(6): 483-489, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30201081

RESUMO

BACKGROUND: Despite improvements in blood donor selection and screening procedures, transfusion recipients can still develop complications related to infections by known and emerging pathogens. Pathogen reduction technologies (PRT) have been developed to reduce such risks. The present study, developed whithin a wider health technology assessment (HTA) process, was undertaken to estimate the costs of the continuing increase in the use of platelet PRT in Italy. MATERIALS AND METHODS: A multidisciplinary team was established to perform the HTA and conduct a budget impact analysis. Quantitative data on platelet use were derived from the 2015 national blood transfusion report and from the Italian Platelets Transfusion Assessment Study (IPTAS). The current national fee of 60 Euro per platelet PRT procedure was used to quantify the costs to the Italian National Health Service (INHS). The analysis adopts a 3-year time-frame. In order to identify the impact on budget we compared a scenario representing an increased use of PRT platelets over time with a control scenario in which standard platelets are used. RESULTS: Progressive implementation of PRT for 20%, 40% and 66% of annual adult platelet doses could generate an increase in annual costs for the INHS amounting to approximately 7, 14 and 23 million Euros, respectively. Use of kits and devices suitable for the treatment of multiple adult platelet doses in one PRT procedure could lower costs. DISCUSSION: In order to fully evaluate the societal perspective of implementing platelet PRT, the increase in costs must be balanced against the expected benefits (prevention of transfusion-transmissible infections, white cell inactivation, extension of platelet storage, discontinuation of pathogen detection testing). Further studies based on actual numbers of platelet transfusion complications and their societal cost at a local level are needed to see the full cost to benefit ratio of platelet PRT implementation in Italy, and to promote equal treatment for all citizens.


Assuntos
Plaquetas , Desinfecção/economia , Transfusão de Plaquetas/economia , Adulto , Custos e Análise de Custo , Desinfecção/métodos , Feminino , Humanos , Itália , Masculino
16.
FEMS Microbiol Lett ; 365(20)2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30239707

RESUMO

This study aimed to evaluate viral and bacterial contamination from typical Brazilian cheeses, such as Minas (fresh) and Prato (ripened), commercially obtained in the Greater Metropolitan Region of the State of Rio de Janeiro, Brazil. Minas [30], Prato [30] and sliced Prato [30] cheese samples were investigated for norovirus genogroup I and II (NoV GI-II) and human adenovirus (HAdV) by direct nucleic acid extraction using TRIzol and amplification by TaqMan based quantitative polymerase chain reaction. Listeria monocytogenes, Salmonella spp., coagulase-positive staphylococci (CPS) and fecal coliforms were also assessed by using standard counting methods. NoV GI and GII were detected in one sample (1.1%) each and HAdV in nine samples (10.0%) while bacteriological analysis revealed five samples (5.5%) contaminated with L. monocytogenes, 27 (30.0%) with fecal coliforms and 10 (11.1%) with CPS. Salmonella spp. was not detected in any sample. Viruses were detected in 11 samples (12.2%), of which 9 met the microbiological criteria used to evaluate the microbiological quality of the cheeses, stressing the importance of considering virological parameters for monitoring this food matrix.


Assuntos
Adenoviridae/isolamento & purificação , Bactérias/classificação , Bactérias/isolamento & purificação , Queijo/microbiologia , Queijo/virologia , Norovirus/isolamento & purificação , Adenoviridae/classificação , Adenoviridae/genética , Carga Bacteriana , Brasil , DNA Viral/genética , DNA Viral/isolamento & purificação , Contaminação de Alimentos , Humanos , Norovirus/classificação , Norovirus/genética , RNA Viral/genética , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real
17.
Microbiologyopen ; 7(5): e00593, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29536659

RESUMO

The absence of base excision repair (BER) proteins involved in processing ROS-promoted genetic insults activates a DNA damage scanning (DisA)-dependent checkpoint event in outgrowing Bacillus subtilis spores. Here, we report that genetic disabling of transcription-coupled repair (TCR) or nucleotide excision repair (NER) pathways severely affected outgrowth of ΔdisA spores, and much more so than the effects of these mutations on log phase growth. This defect delayed the first division of spore's nucleoid suggesting that unrepaired lesions affected transcription and/or replication during outgrowth. Accordingly, return to life of spores deficient in DisA/Mfd or DisA/UvrA was severely affected by a ROS-inducer or a replication blocking agent, hydrogen peroxide and 4-nitroquinoline-oxide, respectively. Mutation frequencies to rifampin resistance (Rifr ) revealed that DisA allowed faithful NER-dependent DNA repair but activated error-prone repair in TCR-deficient outgrowing spores. Sequencing analysis of rpoB from spontaneous Rifr colonies revealed that mutations resulting from base deamination predominated in outgrowing wild-type spores. Interestingly, a wide range of base substitutions promoted by oxidized DNA bases were detected in ΔdisA and Δmfd outgrown spores. Overall, our results suggest that Mfd and DisA coordinate excision repair events in spore outgrowth to eliminate DNA lesions that interfere with replication and transcription during this developmental period.


Assuntos
Bacillus subtilis/crescimento & desenvolvimento , Bacillus subtilis/genética , Dano ao DNA , Reparo do DNA , Esporos/crescimento & desenvolvimento , Esporos/genética , Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Replicação do DNA , RNA Polimerases Dirigidas por DNA/genética , Farmacorresistência Bacteriana , Mutação , Espécies Reativas de Oxigênio/toxicidade , Rifampina/farmacologia , Fatores de Transcrição/metabolismo , Transcrição Gênica
18.
J Bacteriol ; 198(24): 3345-3354, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27698084

RESUMO

Aag from Bacillus subtilis has been implicated in in vitro removal of hypoxanthine and alkylated bases from DNA. The regulation of expression of aag in B. subtilis and the resistance to genotoxic agents and mutagenic properties of an Aag-deficient strain were studied here. A strain with a transcriptional aag-lacZ fusion expressed low levels of ß-galactosidase during growth and early sporulation but exhibited increased transcription during late stages of this developmental process. Notably, aag-lacZ expression was higher inside the forespore than in the mother cell compartment, and this expression was abolished in a sigG-deficient background, suggesting a forespore-specific mechanism of aag transcription. Two additional findings supported this suggestion: (i) expression of an aag-yfp fusion was observed in the forespore, and (ii) in vivo mapping of the aag transcription start site revealed the existence of upstream regulatory sequences possessing homology to σG-dependent promoters. In comparison with the wild-type strain, disruption of aag significantly reduced survival of sporulating B. subtilis cells following nitrous acid or methyl methanesulfonate treatments, and the Rifr mutation frequency was significantly increased in an aag strain. These results suggest that Aag protects the genome of developing B. subtilis sporangia from the cytotoxic and genotoxic effects of base deamination and alkylation. IMPORTANCE: In this study, evidence is presented revealing that aag, encoding a DNA glycosylase implicated in processing of hypoxanthine and alkylated DNA bases, exhibits a forespore-specific pattern of gene expression during B. subtilis sporulation. Consistent with this spatiotemporal mode of expression, Aag was found to protect the sporulating cells of this microorganism from the noxious and mutagenic effects of base deamination and alkylation.


Assuntos
Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/enzimologia , Proteínas de Bactérias/metabolismo , DNA Glicosilases/metabolismo , DNA Bacteriano/metabolismo , Hipoxantina/toxicidade , Mutagênicos/toxicidade , Esporos Bacterianos/crescimento & desenvolvimento , Alquilação , Bacillus subtilis/genética , Bacillus subtilis/crescimento & desenvolvimento , Proteínas de Bactérias/genética , DNA Glicosilases/genética , DNA Bacteriano/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Regiões Promotoras Genéticas , Fator sigma/genética , Fator sigma/metabolismo , Esporos Bacterianos/efeitos dos fármacos , Esporos Bacterianos/enzimologia , Esporos Bacterianos/genética
19.
Physiol Behav ; 157: 170-7, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26873413

RESUMO

The abnormal elevation of serum PRL, referred to as hyperprolactinemia (HyperPRL), produces alterations in several reproductive parameters of male rats such as penile erection or decreased tendency to reach ejaculation. Additionally, this situation produces a significant modification of prostate histology, as observed in the epithelial structure and alveolar area, which could reach a level of hyperplasia in the long-term. In this tissue, HyperPRL produces an increase in expression of PRL receptors and activation of the Stat3 signaling pathway that is correlated with the evolution of prostate pathologies. However, the impact of HyperPRL in long-term sexually active male rats is unknown. In this work, using constantly copulating Wistar male rats with induced HyperPRL, we analyzed the level of serum PRL, the effect on prostate PRL receptors, and activation of pStat3, pStat5 and Mapk signaling pathways. Two procedures to induce HyperPRL were employed, comprising daily IP administration or adenohypophysis transplant, and although neither affected the execution of sexual behavior, the serum PRL profile following successive ejaculations was affected. Messenger RNA expression of the short and long isoforms of the PRL receptor at the ventral prostate was affected in different ways depending on the procedure to induce HyperPRL. The ventral prostate did not show any modification in terms of activation of the pStat5 signaling pathway in subjects with daily administration of PRL, although this was significantly increased in ADH transplanted subjects in the second and fourth consecutive ejaculation. A similar profile was found for the pStat3 pathway which additionally showed a significant increase in the third and fourth ejaculation of daily-injected subjects. The Mapk signaling pathway did not show any modifications in subjects with daily administration of PRL, but showed a significant increase in the second and third ejaculations of subjects with ADH transplants. Thus, although sexual behavior was not modified, HyperPRL modified the expression of PRL receptors and the activation of signal pathways in the prostate tissue. Hence, it is probable that prostatic alterations precede the sexual behavioral deficits observed in subjects with HyperPRL.


Assuntos
Hiperprolactinemia/patologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Próstata/metabolismo , Receptores da Prolactina/metabolismo , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais/fisiologia , Análise de Variância , Animais , Copulação/fisiologia , Feminino , Regulação da Expressão Gênica , Hiperprolactinemia/induzido quimicamente , Masculino , Ovariectomia , Prolactina/efeitos adversos , Prolactina/sangue , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Esteroides/metabolismo
20.
FEMS Microbiol Lett ; 363(4)2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26781916

RESUMO

Cry proteins are pesticidal toxins produced by the bacterium Bacillus thuringiensis (Bt), which aggregate in sporulating cells to form a crystal. Except in a relatively few cases, these crystals are located outside the exosporium that surrounds the spore. Bt2-56 is a strain of Bt that has the relatively uncommon characteristic of locating its Cry protein-containing crystal within the exosporium, and in association with a long, multifiber filament. With the ultimate goal of both understanding and manipulating the localization of Cry proteins within the exosporium, we sought to identify the genes coding for the exosporium-localized Cry proteins in Bt2-56. Herein we show (i) that five cry-like genes are present in the genome of Bt2-56, (ii) that two pairs of these genes show organizational similarity to a relatively uncommon gene configuration that coexpress a cry gene along with a gene whose product aids crystal formation and (iii) that when one of these two gene pairs (cry21A-cdA) is expressed in an acrystalliferous strain of Bt, crystals are formed that localize within the exosporium. In Bt ssp. finitimus, the only other strain in which crystal localization has been studied, a Cry protein needed expression of two non-cry ORFs in order to localize within the exosporium, indicating that there are some mechanistic differences for crystal localization between Bt ssp. finitimus and Bt2-56.


Assuntos
Bacillus thuringiensis/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Parede Celular/genética , Endotoxinas/química , Endotoxinas/genética , Proteínas Hemolisinas/química , Proteínas Hemolisinas/genética , Esporos Bacterianos/química , Bacillus thuringiensis/química , Toxinas de Bacillus thuringiensis , Agentes de Controle Biológico/química , Parede Celular/química , Regulação Bacteriana da Expressão Gênica , Ordem dos Genes , Genoma Bacteriano
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