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1.
Int J Mol Sci ; 24(4)2023 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-36835561

RESUMEN

The cpdB gene is pro-virulent in avian pathogenic Escherichia coli and in Salmonella enterica, where it encodes a periplasmic protein named CpdB. It is structurally related to cell wall-anchored proteins, CdnP and SntA, encoded by the also pro-virulent cdnP and sntA genes of Streptococcus agalactiae and Streptococcus suis, respectively. CdnP and SntA effects are due to extrabacterial hydrolysis of cyclic-di-AMP, and to complement action interference. The mechanism of CpdB pro-virulence is unknown, although the protein from non-pathogenic E. coli hydrolyzes cyclic dinucleotides. Considering that the pro-virulence of streptococcal CpdB-like proteins is mediated by c-di-AMP hydrolysis, S. enterica CpdB activity was tested as a phosphohydrolase of 3'-nucleotides, 2',3'-cyclic mononucleotides, linear and cyclic dinucleotides, and cyclic tetra- and hexanucleotides. The results help to understand cpdB pro-virulence in S. enterica and are compared with E. coli CpdB and S. suis SntA, including the activity of the latter on cyclic-tetra- and hexanucleotides reported here for the first time. On the other hand, since CpdB-like proteins are relevant to host-pathogen interactions, the presence of cpdB-like genes was probed in eubacterial taxa by TblastN analysis. The non-homogeneous genomic distribution revealed taxa with cpdB-like genes present or absent, identifying eubacteria and plasmids where they can be relevant.


Asunto(s)
Proteínas de Escherichia coli , Salmonella enterica , Streptococcus suis , Escherichia coli/metabolismo , Salmonella enterica/metabolismo , Streptococcus suis/metabolismo , Virulencia , AMP Cíclico , Genómica , Proteínas de Escherichia coli/metabolismo , 2',3'-Nucleótido Cíclico Fosfodiesterasas/genética
2.
Int J Mol Sci ; 22(4)2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33671286

RESUMEN

CpdB is a 3'-nucleotidase/2'3'-cyclic nucleotide phosphodiesterase, active also with reasonable efficiency on cyclic dinucleotides like c-di-AMP (3',5'-cyclic diadenosine monophosphate) and c-di-GMP (3',5'-cyclic diadenosine monophosphate). These are regulators of bacterial physiology, but are also pathogen-associated molecular patterns recognized by STING to induce IFN-ß response in infected hosts. The cpdB gene of Gram-negative and its homologs of gram-positive bacteria are virulence factors. Their protein products are extracytoplasmic enzymes (either periplasmic or cell-wall anchored) and can hydrolyze extracellular cyclic dinucleotides, thus reducing the innate immune responses of infected hosts. This makes CpdB(-like) enzymes potential targets for novel therapeutic strategies in infectious diseases, bringing about the necessity to gain insight into the molecular bases of their catalytic behavior. We have dissected the two-domain structure of Escherichia coli CpdB to study the role of its N-terminal and C-terminal domains (CpdB_Ndom and CpdB_Cdom). The specificity, kinetics and inhibitor sensitivity of point mutants of CpdB, and truncated proteins CpdB_Ndom and CpdB_Cdom were investigated. CpdB_Ndom contains the catalytic site, is inhibited by phosphate but not by adenosine, while CpdB_Cdom is inactive but contains a substrate-binding site that determines substrate specificity and adenosine inhibition of CpdB. Among CpdB substrates, 3'-AMP, cyclic dinucleotides and linear dinucleotides are strongly dependent on the CpdB_Cdom binding site for activity, as the isolated CpdB_Ndom showed much-diminished activity on them. In contrast, 2',3'-cyclic mononucleotides and bis-4-nitrophenylphosphate were actively hydrolyzed by CpdB_Ndom, indicating that they are rather independent of the CpdB_Cdom binding site.


Asunto(s)
2',3'-Nucleótido Cíclico Fosfodiesterasas/química , 2',3'-Nucleótido Cíclico Fosfodiesterasas/metabolismo , Adenosina/metabolismo , Biocatálisis , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Fosfatos/metabolismo , 2',3'-Nucleótido Cíclico Fosfodiesterasas/genética , Sitios de Unión , Dominio Catalítico , Proteínas de Escherichia coli/genética , Histidina/metabolismo , Hidrólisis , Cinética , Modelos Moleculares , Mutación Puntual/genética , Dominios Proteicos , Relación Estructura-Actividad , Especificidad por Sustrato
3.
Emerg Infect Dis ; 23(9): 1531-1534, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28820131

RESUMEN

In April 2016, an outbreak of gastrointestinal illness (4,136 cases) occurred in Catalonia, Spain. We detected high levels of norovirus genotypes I and II in office water coolers associated with the outbreak. Infectious viral titer estimates were 33-49 genome copies/L for genotype I and 327-660 genome copies/L for genotype II.


Asunto(s)
Infecciones por Caliciviridae/epidemiología , Brotes de Enfermedades , Agua Potable/virología , Gastroenteritis/epidemiología , Norovirus/aislamiento & purificación , Microbiología del Agua , Infecciones por Caliciviridae/virología , Gastroenteritis/virología , Genotipo , Humanos , Norovirus/clasificación , Norovirus/genética , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , España/epidemiología
4.
J Biol Chem ; 289(15): 10620-10636, 2014 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-24569995

RESUMEN

Mammalian triokinase, which phosphorylates exogenous dihydroxyacetone and fructose-derived glyceraldehyde, is neither molecularly identified nor firmly associated to an encoding gene. Human FMN cyclase, which splits FAD and other ribonucleoside diphosphate-X compounds to ribonucleoside monophosphate and cyclic X-phosphodiester, is identical to a DAK-encoded dihydroxyacetone kinase. This bifunctional protein was identified as triokinase. It was modeled as a homodimer of two-domain (K and L) subunits. Active centers lie between K1 and L2 or K2 and L1: dihydroxyacetone binds K and ATP binds L in different subunits too distant (≈ 14 Å) for phosphoryl transfer. FAD docked to the ATP site with ribityl 4'-OH in a possible near-attack conformation for cyclase activity. Reciprocal inhibition between kinase and cyclase reactants confirmed substrate site locations. The differential roles of protein domains were supported by their individual expression: K was inactive, and L displayed cyclase but not kinase activity. The importance of domain mobility for the kinase activity of dimeric triokinase was highlighted by molecular dynamics simulations: ATP approached dihydroxyacetone at distances below 5 Å in near-attack conformation. Based upon structure, docking, and molecular dynamics simulations, relevant residues were mutated to alanine, and kcat and Km were assayed whenever kinase and/or cyclase activity was conserved. The results supported the roles of Thr(112) (hydrogen bonding of ATP adenine to K in the closed active center), His(221) (covalent anchoring of dihydroxyacetone to K), Asp(401) and Asp(403) (metal coordination to L), and Asp(556) (hydrogen bonding of ATP or FAD ribose to L domain). Interestingly, the His(221) point mutant acted specifically as a cyclase without kinase activity.


Asunto(s)
Liasas de Fósforo-Oxígeno/química , Liasas de Fósforo-Oxígeno/fisiología , Fosfotransferasas (Aceptor de Grupo Alcohol)/química , Animales , Catálisis , Dominio Catalítico , Dimerización , Flavina-Adenina Dinucleótido/química , Fructosa/química , Gliceraldehído/química , Humanos , Concentración de Iones de Hidrógeno , Cinética , Simulación de Dinámica Molecular , Mutagénesis Sitio-Dirigida , Mutación , Fosforilación , Estructura Terciaria de Proteína , Proteínas Recombinantes/química , Especificidad por Sustrato , Porcinos
5.
Sci Total Environ ; 892: 164495, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37245831

RESUMEN

Wastewater-based surveillance can be a valuable tool to monitor viral circulation and serve as an early warning system. For respiratory viruses that share similar clinical symptoms, namely SARS-CoV-2, influenza, and respiratory syncytial virus (RSV), identification in wastewater may allow differentiation between seasonal outbreaks and COVID-19 peaks. In this study, to monitor these viruses as well as standard indicators of fecal contamination, a weekly sampling campaign was carried out for 15 months (from September 2021 to November 2022) in two wastewater treatment plants that serve the entire population of Barcelona (Spain). Samples were concentrated by the aluminum hydroxide adsorption-precipitation method and then analyzed by RNA extraction and RT-qPCR. All samples were positive for SARS-CoV-2, while the positivity rates for influenza virus and RSV were significantly lower (10.65 % for influenza A (IAV), 0.82 % for influenza B (IBV), 37.70 % for RSV-A and 34.43 % for RSV-B). Gene copy concentrations of SARS-CoV-2 were often approximately 1 to 2 logarithmic units higher compared to the other respiratory viruses. Clear peaks of IAV H3:N2 in February and March 2022 and RSV in winter 2021 were observed, which matched the chronological incidence of infections recorded in the Catalan Government clinical database. In conclusion, the data obtained from wastewater surveillance provided new information on the abundance of respiratory viruses in the Barcelona area and correlated favorably with clinical data.


Asunto(s)
COVID-19 , Gripe Humana , Infecciones por Virus Sincitial Respiratorio , Virus , Humanos , Gripe Humana/epidemiología , Virus Sincitiales Respiratorios/genética , Aguas Residuales , COVID-19/epidemiología , SARS-CoV-2 , Monitoreo Epidemiológico Basado en Aguas Residuales , Infecciones por Virus Sincitial Respiratorio/epidemiología
6.
Water Res ; 231: 119621, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36693290

RESUMEN

Besides nasopharyngeal swabs, monkeypox virus (MPXV) DNA has been detected in a variety of samples such as saliva, semen, urine and fecal samples. Using the environmental surveillance network previously developed in Spain for the routine wastewater surveillance of SARS-CoV-2 (VATar COVID-19), we have analyzed the presence of MPXV DNA in wastewater from different areas of Spain. Samples (n = 312) from 24 different wastewater treatment plants were obtained between May 9 (week 19 of 2022) and August 4 (week 31 of 2022). Following concentration of viral particles by a validated aluminum adsorption-precipitation method, a qPCR procedure allowed us to detect MPXV DNA in 56 wastewater samples collected from May 16 to August 4, 2022, with values ranging between 2.2 × 103 to 8.7 × 104 genome copies (gc)/L. This study shows that MPXV DNA can be reproducibly detected by qPCR in longitudinal samples collected from different Spanish wastewater treatment plants. According to data from the National Epidemiological Surveillance Network (RENAVE) in Spain a total of 6,119 cases have been confirmed as of August 19, 2022. However, and based on the wastewater data, the reported clinical cases seem to be underestimated and asymptomatic infections may be more frequent than expected.


Asunto(s)
COVID-19 , Monkeypox virus , Humanos , SARS-CoV-2 , Aguas Residuales , Monitoreo Epidemiológico Basado en Aguas Residuales , ADN , ARN Viral
7.
Front Microbiol ; 13: 843068, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35391727

RESUMEN

Streptococcus suis and Streptococcus agalactiae evade the innate immune system of the infected host by mechanisms mediated by cell wall-anchored proteins: SntA and CdnP, respectively. The former has been reported to interfere with complement responses, and the latter dampens STING-dependent type-I interferon (IFN) response by hydrolysis of bacterial cyclic-di-AMP (c-di-AMP). Both proteins are homologous but, while CdnP has been studied as a phosphohydrolase, the enzyme activities of SntA have not been investigated. The core structure of SntA was expressed in Escherichia coli as a GST-tagged protein that, after affinity purification, was characterized as phosphohydrolase with a large series of substrates. This included 3'-nucleotides, 2',3'-cyclic nucleotides, cyclic and linear dinucleotides, and a variety of phosphoanhydride or phosphodiester compounds, most of them previously considered as substrates of E. coli CpdB, a periplasmic protein homologous to SntA and CdnP. Catalytic efficiency was determined for each SntA substrate, either by dividing parameters k cat /K M obtained from saturation curves or directly from initial rates at low substrate concentrations when saturation curves could not be obtained. SntA is concluded to act as phosphohydrolase on two groups of substrates with efficiencies higher or lower than ≈ 105 M-1 s-1 (average value of the enzyme universe). The group with k cat /K M ≥ 105 M-1 s-1 (good substrates) includes 3'-nucleotides, 2',3'-cyclic nucleotides, and linear and cyclic dinucleotides (notably c-di-AMP). Compounds showing efficiencies <104 M-1 s-1 are considered poor substrates. Compared with CpdB, SntA is more efficient with its good substrates and less efficient with its poor substrates; therefore, the specificity of SntA is more restrictive. The efficiency of the SntA activity on c-di-AMP is comparable with the activity of CdnP that dampens type-I IFN response, suggesting that this virulence mechanism is also functional in S. suis. SntA modeling revealed that Y530 and Y633 form a sandwich with the nitrogen base of nucleotidic ligands in the substrate-binding site. Mutants Y530A-SntA, Y633A-SntA, and Y530A+Y633A-SntA were obtained and kinetically characterized. For orientation toward the catalytic site, one tyrosine is enough, although this may depend on the substrate being attacked. On the other hand, both tyrosines are required for the efficient binding of good SntA substrates.

8.
Sci Rep ; 12(1): 16704, 2022 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-36202959

RESUMEN

Wastewater-based epidemiology has shown to be an efficient tool to track the circulation of SARS-CoV-2 in communities assisted by wastewater treatment plants (WWTPs). The challenge comes when this approach is employed to help Health authorities in their decision-making. Here, we describe the roadmap for the design and deployment of SARSAIGUA, the Catalan Surveillance Network of SARS-CoV-2 in Sewage. The network monitors, weekly or biweekly, 56 WWTPs evenly distributed across the territory and serving 6 M inhabitants (80% of the Catalan population). Each week, samples from 45 WWTPs are collected, analyzed, results reported to Health authorities, and finally published within less than 72 h in an online dashboard ( https://sarsaigua.icra.cat ). After 20 months of monitoring (July 20-March 22), the standardized viral load (gene copies/day) in all the WWTPs monitored fairly matched the cumulative number of COVID-19 cases along the successive pandemic waves, showing a good fit with the diagnosed cases in the served municipalities (Spearman Rho = 0.69). Here we describe the roadmap of the design and deployment of SARSAIGUA while providing several open-access tools for the management and visualization of the surveillance data.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , Humanos , Pandemias , ARN Viral , Aguas del Alcantarillado , Aguas Residuales , Monitoreo Epidemiológico Basado en Aguas Residuales
9.
Mol Microbiol ; 78(6): 1556-76, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21143324

RESUMEN

A novel enzyme, induced by choline, ethanolamine, glycine betaine or dimethylglycine, was released at low temperature and phosphate from Pseudomonas fluorescens (CECT 7229) suspensions at low cell densities. It is a CDP-ethanolamine pyrophosphatase/(dihexanoyl)glycerophosphoethanolamine phosphodiesterase (CGDEase) less active on choline derivatives, and inactive on long-chain phospholipids, CDP-glycerol and other NDP-X compounds. The reaction pattern was typical of phospholipase C (PLC), as either phosphoethanolamine or phosphocholine was produced. Peptide-mass analyses, gene cloning and expression provided a molecular identity for CGDEase. Bioinformatic studies assigned it to the PLC branch of the phospholipase C/acid phosphatase (PLC/APase) superfamily, revealed an irregular phylogenetic distribution of close CGDEase relatives, and suggested their genes are not in operons or conserved contexts. A theoretical CGDEase structure was supported by mutagenesis of two predicted active-site residues, which yielded essentially inactive mutants. Biological relevance is supported by comparisons with CGDEase relatives, induction by osmoprotectants (not by osmotic stress itself) and repression by micromolar phosphate. The low bacterial density requirement was related to phosphate liberation from lysed bacteria in denser populations, rather than to a classical quorum-sensing effect. The results fit better a CGDEase role in phosphate scavenging than in osmoprotection.


Asunto(s)
Regulación Enzimológica de la Expresión Génica , Fosfatos/metabolismo , Hidrolasas Diéster Fosfóricas/metabolismo , Pseudomonas fluorescens/enzimología , Pirofosfatasas/metabolismo , Dominio Catalítico , Citidina Difosfato/análogos & derivados , Citidina Difosfato/metabolismo , Etanolaminas/metabolismo , Regulación Bacteriana de la Expresión Génica , Datos de Secuencia Molecular , Familia de Multigenes , Hidrolasas Diéster Fosfóricas/química , Hidrolasas Diéster Fosfóricas/genética , Pseudomonas fluorescens/química , Pseudomonas fluorescens/genética , Pirofosfatasas/química , Pirofosfatasas/genética , Especificidad por Sustrato
10.
Appl Environ Microbiol ; 77(3): 1111-4, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21148702

RESUMEN

Human sapoviruses (SaVs) were quantified and characterized in an 18-month survey conducted along the Llobregat river catchment area in Spain. Sample types included freshwater, untreated and treated wastewater, and drinking water. All genogroups were recovered, and a seasonal distribution was observed. This is the first report of SaV quantification and genotyping in the environment outside Japan.


Asunto(s)
Agua Dulce/virología , Ríos/virología , Sapovirus/genética , Sapovirus/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Abastecimiento de Agua , Monitoreo del Ambiente , Genotipo , Humanos , Datos de Secuencia Molecular , Filogenia , ARN Viral/genética , Sapovirus/clasificación , Estaciones del Año , Análisis de Secuencia de ADN , Aguas del Alcantarillado/microbiología , España , Microbiología del Agua
11.
Environ Int ; 147: 106326, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33340987

RESUMEN

Given the widespread concern but general lack of information over the possibility of SARS-CoV-2 infection in public transport, key issues such as passenger personal hygiene, efficient air circulation systems, and the effective disinfection of frequently touched surfaces need to be evaluated to educate the public and diminish the risk of viral transmission as we learn to live with the ongoing pandemic. In this context we report on a study involving the collection of 99 samples taken from inside Barcelona buses and subway trains in May to July 2020. From this sample group 82 (58 surface swabs, 9 air conditioning (a/c) filters, 3 a/c dust, 12 ambient air) were selected to be analysed by RT-PCR for traces of the SARS-CoV-2 virus. Thirty of these selected samples showed evidence for one or more of 3 target RNA gene regions specific for this virus (IP2, IP4, E). Most (24) of these 30 samples showed positivity for only 1 of the 3 RNA targets, 4 samples yielded 2 targets, and 2 samples provided evidence for all 3 targets. RNA remnants were more common in surface swabs from support bars (23 out of 58) than in ambient air inside the vehicles (3 out of 12), with relatively higher concentrations of viral RNA fragments in buses rather than in trains. Whereas subway train a/c filters examined were all virus-free, 4 of the 9 bus a/c filter/dust samples yielded evidence for viral RNA. After nocturnal maintenance and cleaning most buses initially yielding positive results subsequently showed elimination of the RT-PCR signal, although signs of viral RNA remained in 4 of 13 initially positive samples. The presence of such remnant viral traces however does not demonstrate infectivity, which in the present study is considered unlikely given the fragmentary nature of the gene targets detected. Nevertheless, best practice demands that close attention to ventilation systems and regular vehicle disinfection in public transport worldwide need to be rigorously applied to be effective at eliminating traces of the virus throughout the vehicle, especially at times when COVID-19 cases are peaking. Additionally, infectivity tests should be implemented to evaluate the efficiency of disinfection procedures to complement the information resulting from RT-PCR analysis. Modelling the probability of infection whilst travelling in buses under different scenarios indicates that forced ventilation greatly reduces the risk.


Asunto(s)
COVID-19 , Vías Férreas , Humanos , Vehículos a Motor , Pandemias , ARN Viral , SARS-CoV-2
12.
Sci Rep ; 10(1): 1760, 2020 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-32020041

RESUMEN

Novel human astroviruses (HAstV) were discovered 10 years ago and have been associated with fatal cases of central nervous system infections. Their role in gastroenteritis is controversial, as they have been identified in symptomatic and asymptomatic subjects. The aim of the study was to investigate novel HAstV in a gastroenteritis case-control study including a pediatric population in Spain over a one-year period. We included stool samples from patients with gastroenteritis and negative results for viruses screened by routine diagnostics, and stool samples of control subjects who sought for a routine medical consultation. All samples were screened by real-time RT-PCR assays for novel HAstV. An additional screening for rotavirus, norovirus GI, GII, sapovirus, classic HAstV and adenovirus was also performed for the control group. Overall, 23/363 stool samples from case patients (6.3%) and 8/199 stool samples from control patients (4%) were positive for ≥1 novel HAstV. MLB1 was predominant (64.5% of positives). Seasonality was observed for the case group (p = 0.015), but not the control group (p = 0.95). No difference was observed in the prevalence of novel HAstV between the case and control groups (OR 1.78, 95% CI 0.68-5.45; p = 0.30). Nevertheless, MLB genome copy numbers/ml of fecal suspension was significantly higher in the control group than in the case group (p = 0.008). In our study, we identified a lack of association between novel HAstV and gastroenteritis in the studied population, which could indicate a potential role of reservoir for children, especially given the higher viral load observed in the asymptomatic group for some of them.


Asunto(s)
Infecciones por Astroviridae/virología , Diarrea/virología , Genes Virales/genética , Mamastrovirus/genética , Estudios de Casos y Controles , Niño , Preescolar , Diarrea/etiología , Heces/virología , Femenino , Gastroenteritis/etiología , Gastroenteritis/virología , Dosificación de Gen/genética , Variación Genética/genética , Genotipo , Humanos , Lactante , Recién Nacido , Masculino , Filogenia , Prevalencia , España , Carga Viral/genética
13.
J Am Chem Soc ; 131(29): 10107-12, 2009 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-19569646

RESUMEN

Flavins, comprising flavin mononucleotide (FMN), flavin adenine dinucleotide (FAD), and riboflavin (RF, vitamin B(2)), play important roles in numerous redox reactions such as those taking place in the electron-transfer chains of mitochondria in all eukaryotes and of plastids in plants. A selective chemosensor for flavins would be useful not only in the investigation of metabolic processes but also in the diagnosis of diseases related to flavins; such a sensor is presently unavailable. Herein, we report the first bifunctional chemosensor (PTZ-DPA) for flavins. PTZ-DPA consists of bis(Zn(2+)-dipicolylamine) and phenothiazine. Bis(Zn(2+)-dipicolylamine) (referred to here as XyDPA) was found to be an excellent catalyst in the conversion of FAD into cyclic FMN (riboflavin 4',5'-cyclic phosphate, cFMN) under physiological conditions, even at pH 7.4 and 27 degrees C, with less than 1 mol % of substrate. Utilizing XyDPA's superior function as an artificial FMN cyclase and phenothiazine as an electron donor able to quench the fluorescence of an isoalloxazine ring, PTZ-DPA enabled selective fluorescent discrimination of flavins (FMN, FAD, and RF): FAD shows ON(+), FMN shows OFF(-), and RF shows NO(0) fluorescence changes upon the addition of PTZ-DPA. With this selective sensing property, PTZ-DPA is applicable to real-time fluorescent monitoring of riboflavin kinase (RF to FMN), alkaline phosphatase (FMN to RF), and FAD synthetase (FMN to FAD).


Asunto(s)
Materiales Biomiméticos/química , Técnicas de Química Analítica/métodos , Flavinas/análisis , Fluorescencia , Compuestos Organometálicos/química , Liasas de Fósforo-Oxígeno/metabolismo , Aminas/química , Materiales Biomiméticos/metabolismo , Mononucleótido de Flavina/análisis , Mononucleótido de Flavina/metabolismo , Colorantes Fluorescentes/análisis , Colorantes Fluorescentes/química , Mediciones Luminiscentes , Estructura Molecular , Ácidos Picolínicos/química , Zinc/química
14.
Viruses ; 11(7)2019 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-31252663

RESUMEN

A remarkable percentage of acute gastroenteritis cases remain etiologically undiagnosed. The aim of the study was to determine the prevalence of common and emerging enteric viruses, such as novel human astroviruses, among undiagnosed samples from children with acute gastroenteritis. Epidemiological studies for novel human astroviruses are still scarce. Stool samples collected over two consecutive winter seasons (2016-2017) from children with gastroenteritis in Spain, which were negative for bacteria, rotavirus, and adenovirus by routine diagnostics were screened by real-time RT-PCR assays for the presence of classical and novel astrovirus, rotavirus, norovirus GI and GII, sapovirus, and adenovirus. Overall, 220/384 stool samples (57.3%) were positive for at least one virus. Co-infections were identified in 21% of cases. Among a total of 315 viruses identified, adenovirus was the most prevalent (n = 103), followed by rotavirus (n = 51), sapovirus (n = 50), classical astrovirus (n = 43), novel astroviruses (n = 42), and norovirus (n = 26). Novel astroviruses were present in 13.3% of virus-positive cases. Most novel astroviruses were found in children <2-year-old (30/39 children, 77%, p = 0.01) and were found in co-infection (66%). Only classical astroviruses demonstrated significant differences in the Cq values during mono-infections compared to co-infections. In conclusion, common enteric viruses may be frequently found in children with undiagnosed gastroenteritis, indicating the need to implement more sensitive diagnostic methods. Novel astroviruses circulate in the community and could be the cause of gastroenteritis among young children.


Asunto(s)
Infecciones por Astroviridae/virología , Gastroenteritis/virología , Mamastrovirus/aislamiento & purificación , Infecciones por Astroviridae/diagnóstico , Infecciones por Astroviridae/epidemiología , Preescolar , Heces/virología , Femenino , Gastroenteritis/diagnóstico , Gastroenteritis/epidemiología , Humanos , Lactante , Masculino , Mamastrovirus/clasificación , Mamastrovirus/genética , Prevalencia , España/epidemiología
15.
Sci Rep ; 8(1): 1036, 2018 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-29348648

RESUMEN

Cyclic ADP-ribose (cADPR) is a messenger for Ca2+ mobilization. Its turnover is believed to occur by glycohydrolysis to ADP-ribose. However, ADP-ribose/CDP-alcohol diphosphatase (ADPRibase-Mn) acts as cADPR phosphohydrolase with much lower efficiency than on its major substrates. Recently, we showed that mutagenesis of human ADPRibase-Mn at Phe37, Leu196 and Cys253 alters its specificity: the best substrate of the mutant F37A + L196F + C253A is cADPR by a short difference, Cys253 mutation being essential for cADPR preference. Its proximity to the 'northern' ribose of cADPR in docking models indicates Cys253 is a steric constraint for cADPR positioning. Aiming to obtain a specific cADPR phosphohydrolase, new mutations were tested at Asp250, Val252, Cys253 and Thr279, all near the 'northern' ribose. First, the mutant F37A + L196F + C253G, with a smaller residue 253 (Ala > Gly), showed increased cADPR specificity. Then, the mutant F37A + L196F + V252A + C253G, with another residue made smaller (Val > Ala), displayed the desired specificity, with cADPR kcat/KM ≈20-200-fold larger than for any other substrate. When tested in nucleotide mixtures, cADPR was exhausted while others remained unaltered. We suggest that the specific cADPR phosphohydrolase, by cell or organism transgenesis, or the designed mutations, by genome editing, provide opportunities to study the effect of cADPR depletion on the many systems where it intervenes.


Asunto(s)
ADP-Ribosil Ciclasa/química , ADP-Ribosil Ciclasa/metabolismo , ADP-Ribosa Cíclica/química , ADP-Ribosa Cíclica/metabolismo , Manganeso/química , Manganeso/metabolismo , ADP-Ribosilación , ADP-Ribosil Ciclasa/genética , Diseño de Fármacos , Activación Enzimática , Humanos , Ligandos , Modelos Moleculares , Mutación , Unión Proteica , Relación Estructura-Actividad , Especificidad por Sustrato
16.
Virus Res ; 239: 115-125, 2017 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-28040474

RESUMEN

The hepatitis viruses represent a major public health problem worldwide. Procedures for characterization of the genomic composition of their populations, accurate diagnosis, identification of multiple infections, and information on inhibitor-escape mutants for treatment decisions are needed. Deep sequencing methodologies are extremely useful for these viruses since they replicate as complex and dynamic quasispecies swarms whose complexity and mutant composition are biologically relevant traits. Population complexity is a major challenge for disease prevention and control, but also an opportunity to distinguish among related but phenotypically distinct variants that might anticipate disease progression and treatment outcome. Detailed characterization of mutant spectra should permit choosing better treatment options, given the increasing number of new antiviral inhibitors available. In the present review we briefly summarize our experience on the use of deep sequencing for the management of hepatitis virus infections, particularly for hepatitis B and C viruses, and outline some possible new applications of deep sequencing for these important human pathogens.


Asunto(s)
Genoma Viral , Virus de Hepatitis/genética , Hepatitis Viral Humana/virología , Secuenciación de Nucleótidos de Alto Rendimiento , Animales , Antivirales/farmacología , Antivirales/uso terapéutico , Manejo de la Enfermedad , Farmacorresistencia Viral , Genómica/métodos , Genotipo , Hepacivirus/efectos de los fármacos , Hepacivirus/genética , Virus de la Hepatitis B/efectos de los fármacos , Virus de la Hepatitis B/genética , Virus de la Hepatitis Delta/efectos de los fármacos , Virus de la Hepatitis Delta/genética , Virus de Hepatitis/efectos de los fármacos , Hepatitis Viral Humana/diagnóstico , Hepatitis Viral Humana/terapia , Humanos , Mutación , Insuficiencia del Tratamiento , Resultado del Tratamiento
17.
PLoS One ; 11(6): e0157308, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27294396

RESUMEN

Endogenous cyclic diadenylate phosphodiesterase activity was accidentally detected in lysates of Escherichia coli BL21. Since this kind of activity is uncommon in Gram-negative bacteria, its identification was undertaken. After partial purification and analysis by denaturing gel electrophoresis, renatured activity correlated with a protein identified by fingerprinting as CpdB (cpdB gene product), which is annotated as 3´-nucleotidase / 2´,3´-cyclic-mononucleotide phosphodiesterase, and it is synthesized as a precursor protein with a signal sequence removable upon export to the periplasm. It has never been studied as a recombinant protein. The coding sequence of mature CpdB was cloned and expressed as a GST fusion protein. The study of the purified recombinant protein, separated from GST, confirmed CpdB annotation. The assay of catalytic efficiencies (kcat/Km) for a large substrate set revealed novel CpdB features, including very high efficiencies for 3´-AMP and 2´,3´-cyclic mononucleotides, and previously unknown activities on cyclic and linear dinucleotides. The catalytic efficiencies of the latter activities, though low in relative terms when compared to the major ones, are far from negligible. Actually, they are perfectly comparable to those of the 'average' enzyme and the known, bona fide cyclic dinucleotide phosphodiesterases. On the other hand, CpdB differs from these enzymes in its extracytoplasmic location and in the absence of EAL, HD and DHH domains. Instead, it contains the domains of the 5´-nucleotidase family pertaining to the metallophosphoesterase superfamily, although CpdB lacks 5´-nucleotidase activity. The possibility that the extracytoplasmic activity of CpdB on cyclic dinucleotides could have physiological meaning is discussed.


Asunto(s)
2',3'-Nucleótido Cíclico Fosfodiesterasas/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Nucleotidasas/metabolismo , Nucleótidos Cíclicos/metabolismo , Hidrolasas Diéster Fosfóricas/metabolismo , 2',3'-Nucleótido Cíclico Fosfodiesterasas/genética , 3',5'-AMP Cíclico Fosfodiesterasas/genética , 3',5'-AMP Cíclico Fosfodiesterasas/metabolismo , Clonación Molecular , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Nucleotidasas/genética , Hidrolasas Diéster Fosfóricas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
18.
PLoS One ; 10(2): e0118680, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25692488

RESUMEN

Among metallo-dependent phosphatases, ADP-ribose/CDP-alcohol diphosphatases form a protein family (ADPRibase-Mn-like) mainly restricted, in eukaryotes, to vertebrates and plants, with preferential expression, at least in rodents, in immune cells. Rat and zebrafish ADPRibase-Mn, the only biochemically studied, are phosphohydrolases of ADP-ribose and, somewhat less efficiently, of CDP-alcohols and 2´,3´-cAMP. Furthermore, the rat but not the zebrafish enzyme displays a unique phosphohydrolytic activity on cyclic ADP-ribose. The molecular basis of such specificity is unknown. Human ADPRibase-Mn showed similar activities, including cyclic ADP-ribose phosphohydrolase, which seems thus common to mammalian ADPRibase-Mn. Substrate docking on a homology model of human ADPRibase-Mn suggested possible interactions of ADP-ribose with seven residues located, with one exception (Cys253), either within the metallo-dependent phosphatases signature (Gln27, Asn110, His111), or in unique structural regions of the ADPRibase-Mn family: s2s3 (Phe37 and Arg43) and h7h8 (Phe210), around the active site entrance. Mutants were constructed, and kinetic parameters for ADP-ribose, CDP-choline, 2´,3´-cAMP and cyclic ADP-ribose were determined. Phe37 was needed for ADP-ribose preference without catalytic effect, as indicated by the increased ADP-ribose Km and unchanged kcat of F37A-ADPRibase-Mn, while the Km values for the other substrates were little affected. Arg43 was essential for catalysis as indicated by the drastic efficiency loss shown by R43A-ADPRibase-Mn. Unexpectedly, Cys253 was hindering for cADPR phosphohydrolase, as indicated by the specific tenfold gain of efficiency of C253A-ADPRibase-Mn with cyclic ADP-ribose. This allowed the design of a triple mutant (F37A+L196F+C253A) for which cyclic ADP-ribose was the best substrate, with a catalytic efficiency of 3.5´104 M-1s-1 versus 4´103 M-1s-1 of the wild type.


Asunto(s)
Ácido Anhídrido Hidrolasas/química , Ácido Anhídrido Hidrolasas/genética , Adenosina Difosfato Ribosa/metabolismo , Apirasa/química , Apirasa/genética , Manganeso/metabolismo , Ácido Anhídrido Hidrolasas/metabolismo , Animales , Apirasa/metabolismo , Dominio Catalítico , Humanos , Hígado/metabolismo , Modelos Moleculares , Simulación del Acoplamiento Molecular , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Ratas , Homología Estructural de Proteína
19.
Cad Saude Publica ; 20(3): 836-44, 2004.
Artículo en Portugués | MEDLINE | ID: mdl-15263995

RESUMEN

To report on the clientele treated at community mental health services (CAPS) in the city of Santos, São Paulo, Brazil, a census was conducted of the patients examined at the services from June 1, 2001, to June 30, 2001. The patient's initial contact with the service was registered, and data were recorded on a standardized form, using the medical case history as a source of information. Among the 1,673 patients, average age was 46 years, 59.0% were female, 58.0% lived with their families, and mean duration of treatment was three years. Some 38.0% were schizophrenic, schizotypical, or in acute delusional states, 31.0% presented mood disorders, and 17.0% were neurotic. Treatment modalities included out-patient psychiatric (81.0%), individual (23.0%), group (13.0%), and psychosocial rehabilitation (4.3%). In Santos, CAPS treat all categories of mental disorders (and frequently those considered the most severe cases) expected at this type of service. The treatment model is that of an out-patient psychiatric clinic.


Asunto(s)
Servicios Comunitarios de Salud Mental/estadística & datos numéricos , Trastornos Mentales/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Esquizofrenia/terapia
20.
Rev. bras. educ. méd ; 41(3): 449-453, jul.-set. 2017. tab
Artículo en Portugués | LILACS | ID: biblio-898132

RESUMEN

RESUMO Na atualidade, não há mais dúvidas sobre a importância das ciências humanas e humanidades no currículo médico, isto já é consenso. É necessário retomar, pelo menos parcialmente, a capacidade de empatia e comunicação dos futuros médicos, a exemplo do que se tinha outrora, além do olhar sistêmico para que os pacientes possam se sentir mais bem acolhidos, o que é muito bem ilustrado no texto da médica Tatiana Bruscky, produzido pela Ria Slides: "Onde andará o meu doutor"4. No entanto, ainda não foi encontrada uma forma sistematizada de trabalhar esses conceitos, apesar das iniciativas que vêm ocorrendo no Brasil, principalmente após 2014, visto que as Diretrizes Curriculares para os cursos de graduação em Medicina inseriram ainda mais aspectos relacionados à comunicação médico-paciente. Introduzir esses assuntos e discussões no ensino dos cursos de Medicina é uma tarefa difícil, pois, quase sempre, dosar teoria e prática e tornar as disciplinas que as compõem atrativas e valorizadas pelos alunos são um grande desafio. Não existem parâmetros claros e nem descrições pormenorizadas das metodologias utilizadas, apenas breves relatos. Este artigo aborda, detalhadamente, uma das formas de ensinar humanidades no curso de Medicina do Centro Universitário Lusíada (Unilus), descrevendo a metodologia passo a passo, a experiência e alguns resultados desde a sua implantação em 2010, com uma estação denominada Comunicação, pertencente à disciplina de Habilidades Práticas. Ela é desenvolvida nos três primeiros anos, sendo que no primeiro o foco é a comunicação entre médico, paciente e familiares em situações diversas de consulta; no segundo ano, é a comunicação de más notícias, enquanto no terceiro o enfoque são os cuidados na comunicação do pré e pós-operatório. Por meio de simulações, os alunos conseguem treinar e refletir sobre uma vasta gama de casos e contextos, dos mais simples aos mais complexos. O intuito é compartilhar a didática aplicada e estimular a discussão e a troca de experiências entre profissionais interessados e comprometidos com a excelência na formação médica.


ABSTRACT At the present there is no longer any doubt about the importance of human sciences and humanities in the medical curriculum. This is already a consensus. It is necessary to resume at least partially the ability of future doctors to empathize and communicate as in the past in addition to the systemic view so that patients can feel better welcomed which is very well illustrated in the text of the doctor Tatiana Bruscky produced by Ria Slides: "Onde andará o meu doutor"4. However, finding a systematized way of working on these concepts still does not exist despite the initiatives that have been taking place in Brazil, especially after 2014, since the Curriculum Guidelines for undergraduate courses in Medicine have inserted even more aspects related to this medical / patient communication. Introducing these subjects and discussions in the teaching of medical courses is a difficult task since almost always dosing theory and practice and making the disciplines attractive and valued by the students is a great challenge. There are no clear parameters or detailed descriptions of the methodologies used only brief reports. This article seeks to address in detail one of the ways of teaching humanities in the Centro Universitário Lusíada (Unilus) medical course, describing the step-by-step methodology, experience and some results since its implementation in 2010 with a Station called Communication belonging to the discipline of Practical Skills. It is developed in the first three years. In the first year the focus is the communication between doctor and patient/family in different consultation situations. The second year is the communication of bad news while in the third the focus is the communication of pre and postoperative. In that way students can train and reflect through simulations a wide range of cases and contexts from the simplest to the most complex. The purpose is to share applied didactics and stimulate the discussion and exchange of experience among interested professionals committed to excellence in medical education.

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