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1.
Appl Environ Microbiol ; 88(23): e0150422, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36350137

RESUMEN

The rhamnose-glucose polysaccharide (Rgp) of Streptococcus thermophilus represents a major cell wall component, and the gene cluster responsible for its biosynthesis (termed rgp) has recently been identified. Significant genetic diversity among these loci has previously been reported, with five distinct rgp genotypes identified (designated rgp1 through -5). In the present study, two additional genotypes were identified (designated rgp6 and rgp7) through comparative analysis of the rgp loci of 78 Streptococcus thermophilus genomes. The rgp locus of a given S. thermophilus strain encoded the biosynthetic machinery for a rhamnan-rich backbone and a variable side chain component, the latter being associated with the highly specific interactions with many bacteriophages that infect this species. The chemical structure of the Rgp from three S. thermophilus strains, representing the rgp2, -3, and -4 genotypes, was elucidated, and based on bioinformatic and biochemical analyses we propose a model for Rgp biosynthesis in dairy streptococci. Furthermore, we exploited the genetic diversity within the S. thermophilus bipartite rgp locus to develop a two-step multiplex PCR system to classify strains based on gene content associated with the biosynthesis of the variable side chain structure as well as the rhamnan backbone. IMPORTANCE Streptococcus thermophilus is present and applied in industrial and artisanal dairy fermentations for the production of various cheeses and yogurt. During these fermentations, S. thermophilus is vulnerable to phage predation, and recent studies have identified the rhamnose-glucose polymer (Rgp) as the definitive receptor for at least one problematic phage species. Detailed analysis of S. thermophilus rgp loci has revealed an unprecedented level of genetic diversity, particularly within the glycosyltransferase-encoding gene content of a given locus. Our study shows that this genetic diversity reflects the biochemical structure(s) of S. thermophilus Rgp. As such, we harnessed the genetic diversity of S. thermophilus rgp loci to develop a two-step multiplex PCR method for the classification of strain collections and, ultimately, the formation of phage-robust rational starter sets.


Asunto(s)
Ramnosa , Streptococcus thermophilus , Streptococcus thermophilus/genética , Pared Celular , Polisacáridos , Yogur
2.
Appl Environ Microbiol ; 88(1): e0172321, 2022 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-34669424

RESUMEN

Four bacteriophage-insensitive mutants (BIMs) of the dairy starter bacterium Streptococcus thermophilus UCCSt50 were isolated following challenge with Brussowvirus SW13. The BIMs displayed an altered sedimentation phenotype. Whole-genome sequencing and comparative genomic analysis of the BIMs uncovered mutations within a family 2 glycosyltransferase-encoding gene (orf06955UCCSt50) located within the variable region of the cell wall-associated rhamnose-glucose polymer (Rgp) biosynthesis locus (designated the rgp gene cluster here). Complementation of a representative BIM, S. thermophilus B1, with native orf06955UCCSt50 restored phage sensitivity comparable to that of the parent strain. Detailed bioinformatic analysis of the gene product of orf06955UCCSt50 identified it as a functional homolog of the Lactococcus lactis polysaccharide pellicle (PSP) initiator WpsA. Biochemical analysis of cell wall fractions of strains UCCSt50 and B1 determined that mutations within orf06955UCCSt50 result in the loss of the side chain decoration from the Rgp backbone structure. Furthermore, it was demonstrated that the intact Rgp structure incorporating the side chain structure is essential for phage binding through fluorescence labeling studies. Overall, this study confirms that the rgp gene cluster of S. thermophilus encodes the biosynthetic machinery for a cell surface-associated polysaccharide that is essential for binding and subsequent infection by Brussowviruses, thus enhancing our understanding of S. thermophilus phage-host dynamics. IMPORTANCE Streptococcus thermophilus is an important starter culture bacterium in global dairy fermentation processes, where it is used for the production of various cheeses and yogurt. Bacteriophage predation of the species can result in substandard product quality and, in rare cases, complete fermentation collapse. To mitigate these risks, it is necessary to understand the phage-host interaction process, which commences with the recognition of, and adsorption to, specific host-encoded cell surface receptors by bacteriophage(s). As new groups of S. thermophilus phages are being discovered, the importance of underpinning the genomic elements that specify the surface receptor(s) is apparent. Our research identifies a single gene that is critical for the biosynthesis of a saccharidic moiety required for phage adsorption to its S. thermophilus host. The acquired knowledge provides novel insights into phage-host interactions for this economically important starter species.


Asunto(s)
Bacteriófagos , Siphoviridae , Fagos de Streptococcus , Bacteriófagos/genética , Polisacáridos , Fagos de Streptococcus/genética , Streptococcus thermophilus/genética
3.
J Hum Evol ; 163: 103126, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34954400

RESUMEN

Reconstructing the life histories of extinct hominins remains one of the main foci of paleoanthropological inquiry, as an extended juvenile period impacts the social and cognitive development of species. However, the paucity of hominin remains, the lack of comparative hominoid data, and the destructive nature of many life history approaches have limited our understanding of the relationship between dental development (eruption) and weaning in primates. Alternatively, the rate of dental wear in early-forming teeth has been suggested a good proxy for the timing of weaning. Here we test this hypothesis on an ontogenetic series of Gorilla gorilla gorilla and Pan troglodytes troglodytes, using geographic information systems-based shape descriptors of M1s in relation to the nitrogen (δ15N) and carbon (δ13C) isotope composition of their associated hair. Results show that Gorilla g. gorilla are fully weaned considerably later than Pan t. troglodytes, that is, after M1s had been in full functional occlusion for some time. Yet, throughout ontogeny, gorilla dental wear rates are greater than they are in chimpanzees. This refutes the hypothesis that the rates of wear of early-forming teeth inform the time of weaning (i.e., nutritional independence). Instead, dietary breadth and seasonal variation in resource availability are implicated. This finding has implications for interpreting the hominin fossil record and raises questions about the triggers for, and the mechanisms of, life history change in hominin evolution. As a case in point, commonalities in life history patterns between early hominins and Western lowland gorillas seem to be a means to mitigate the effects of recurrent (i.e., seasonal) resource limitations and-conceivably-to prevent high infant mortality rates. Taken further, difference between hominid life histories are likely to be of degree, not kind.


Asunto(s)
Hominidae , Desgaste de los Dientes , Animales , Gorilla gorilla , Pan troglodytes , Destete
4.
Arterioscler Thromb Vasc Biol ; 41(2): 934-943, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33147992

RESUMEN

OBJECTIVE: Familial hypercholesterolemia (FH) is characterized by elevated low-density lipoprotein-cholesterol and markedly increased cardiovascular risk. In patients with a genetic diagnosis, low-density lipoprotein receptor (LDLR) mutations account for >90% of cases, apolipoprotein B (APOB) mutations for ≈5% of cases, while proprotein convertase subtilisin kexin type 9 (PCSK9) gain of function mutations are rare (<1% of cases). We aimed to evaluate the functional impact of several novel PCSK9 variants in a cohort of patients with FH by genetic cascade screening and in vitro functionality assays. Approach and Results: Patients with clinically diagnosed FH underwent genetic analysis of LDLR, and if negative, sequential testing of APOB and PCSK9. We analyzed cosegregation of hypercholesterolemia with novel PCSK9 variants. Gain of function status was determined by in silico analyses and validated by in vitro functionality assays. Among 1055 persons with clinical FH, we identified nonsynonymous PCSK9 variants in 27 (2.6%) patients and 7 of these carried one of the 4 previously reported gain of function variants. In the remaining 20 patients with FH, we identified 7 novel PCSK9 variants. The G516V variant (c.1547G>T) was found in 5 index patients and cascade screening identified 15 additional carriers. Low-density lipoprotein-cholesterol levels were higher in these 15 carriers compared with the 27 noncarriers (236±73 versus 124±35 mg/dL; P<0.001). In vitro studies demonstrated the pathogenicity of the G516V variant. CONCLUSIONS: In our study, 1.14% of cases with clinical FH were clearly attributable to pathogenic variants in PCSK9. Pathogenicity is established beyond doubt for the G516V variant.


Asunto(s)
Hiperlipoproteinemia Tipo II/genética , Mutación , Proproteína Convertasa 9/genética , Adulto , Anciano , Biomarcadores/sangre , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/genética , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Células HEK293 , Factores de Riesgo de Enfermedad Cardiaca , Células Hep G2 , Herencia , Humanos , Hiperlipoproteinemia Tipo II/sangre , Hiperlipoproteinemia Tipo II/diagnóstico , Lípidos/sangre , Masculino , Persona de Mediana Edad , Linaje , Fenotipo , Supervivencia sin Progresión , Proproteína Convertasa 9/metabolismo , Medición de Riesgo , Sudáfrica , Factores de Tiempo , Adulto Joven
5.
Nucleic Acids Res ; 48(20): 11244-11258, 2020 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-33021629

RESUMEN

Deletions in mitochondrial DNA (mtDNA) are associated with diverse human pathologies including cancer, aging and mitochondrial disorders. Large-scale deletions span kilobases in length and the loss of these associated genes contributes to crippled oxidative phosphorylation and overall decline in mitochondrial fitness. There is not a united view for how mtDNA deletions are generated and the molecular mechanisms underlying this process are poorly understood. This review discusses the role of replication and repair in mtDNA deletion formation as well as nucleic acid motifs such as repeats, secondary structures, and DNA damage associated with deletion formation in the mitochondrial genome. We propose that while erroneous replication and repair can separately contribute to deletion formation, crosstalk between these pathways is also involved in generating deletions.


Asunto(s)
Reparación del ADN , Replicación del ADN , ADN Mitocondrial/biosíntesis , Enfermedades Genéticas Congénitas/genética , Mitocondrias/genética , Enfermedades Mitocondriales/genética , Roturas del ADN de Doble Cadena , Reparación de la Incompatibilidad de ADN , ADN Mitocondrial/metabolismo , Enfermedades Genéticas Congénitas/metabolismo , Humanos , Mitocondrias/patología , Enfermedades Mitocondriales/metabolismo , Fosforilación Oxidativa , Eliminación de Secuencia
6.
Int J Mol Sci ; 23(12)2022 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-35743236

RESUMEN

Chronic pain is a widespread disorder affecting millions of people and is insufficiently addressed by current classes of analgesics due to significant long-term or high dosage side effects. A promising approach that was recently proposed involves the systemic inhibition of the voltage-gated sodium channel Nav1.7, capable of cancelling pain perception completely. Notwithstanding numerous attempts, currently no drugs have been approved for the inhibition of Nav1.7. The task is complicated by the difficulty of creating a selective drug for Nav1.7, and avoiding binding to the many human paralogs performing fundamental physiological functions. In our work, we obtained a promising set of ligands with up to 5-40-fold selectivity and reaching 5.2 nanomolar binding affinity by employing a proper treatment of the problem and an innovative differential in silico screening procedure to discriminate for affinity and selectivity against the Nav paralogs. The absorption, distribution, metabolism, and excretion (ADME) properties of our top-scoring ligands were also evaluated, with good to excellent results. Additionally, our study revealed that the top-scoring ligand is a stereoisomer of an already-approved drug. These facts could reduce the time required to bring a new effective and selective Nav1.7 inhibitor to the market.


Asunto(s)
Dolor Crónico , Canal de Sodio Activado por Voltaje NAV1.7 , Analgésicos/efectos adversos , Dolor Crónico/tratamiento farmacológico , Descubrimiento de Drogas , Humanos , Ligandos , Canal de Sodio Activado por Voltaje NAV1.7/metabolismo
7.
Int J Mol Sci ; 23(15)2022 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-35897686

RESUMEN

Alloreactive and autoreactive antibodies have been associated with the development of chronic lung allograft dysfunction (CLAD), but their pathogenic role is disputed. Orthotopic left lung transplantation was performed in the Fischer-344 to Lewis rat strain combination followed by the application of ciclosporine for 10 days. Four weeks after transplantation, lipopolysaccharide (LPS) was instilled into the trachea. Lungs were harvested before (postoperative day 28) and after LPS application (postoperative days 29, 33, 40, and 90) for histopathological, immunohistochemical, and Western blot analyses. Recipient serum was collected to investigate circulating antibodies. Lung allografts were more strongly infiltrated by B cells and deposits of immunoglobulin G and M were more prominent in allografts compared to right native lungs or isografts and increased in response to LPS instillation. LPS induced the secretion of autoreactive antibodies into the circulation of allograft and isograft recipients, while alloreactive antibodies were only rarely detected. Infiltration of B cells and accumulation of immunoglobulin, which is observed in allografts treated with LPS but not isografts or native lungs, might contribute to the pathogenesis of experimental CLAD. However, the LPS-induced appearance of circulating autoreactive antibodies does not seem to be related to CLAD, because it is observed in both, isograft and allograft recipients.


Asunto(s)
Bronquiolitis Obliterante , Enfermedad Injerto contra Huésped , Trasplante de Pulmón , Aloinjertos/patología , Animales , Rechazo de Injerto , Enfermedad Injerto contra Huésped/patología , Inmunidad Humoral , Lipopolisacáridos , Pulmón/patología , Trasplante de Pulmón/efectos adversos , Ratas , Ratas Endogámicas Lew
8.
Mol Biol Rep ; 48(2): 1977-1983, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33479830

RESUMEN

Genetics can provide invaluable tools for management and conservation of bee populations, which are declining worldwide. Among these tools, microsatellite are very useful molecular markers for population analyses. The aim of this study was to isolate and characterize microsatellites for Epicharis (Anepicharis) dejeanii and Epicharis (Epicharis) nigrita, two Neotropical species of solitary bees, both exhibiting the habit of nesting in aggregations. Microsatellite loci were identified from two enriched genomic libraries. The characterization and analysis of loci were carried out using 35 females of E. dejeanii and 34 of E. nigrita. In total, we report the development of 12 microsatellite loci for E. dejeanii and 13 for E. nigrita. For E. dejeanii, all loci were polymorphic, the number of alleles per locus ranged from 2 to 12, averaging 8.7 and, observed and expected heterozygosity were 0.485 (range 0.229-0.857) and 0.633 (range 0.288-0.843), respectively. For E. nigrita, only nine out of 13 loci amplified were polymorphic, the number of alleles per locus ranged from 2 to 12, averaging 5.5. For this species, the observed and expected heterozygosity were 0.440 (range 0.118-0.676) and 0.545 (range 0.167-0.814), respectively. Cross-amplification of primers was successful in other Centridini species. The two sets of loci described for E. dejeanii and E. nigrita species are polymorphic and informative and show promising applicability for both population genetic approaches and relatedness on these and other Centridini species.


Asunto(s)
Abejas/genética , Himenópteros/genética , Repeticiones de Microsatélite/genética , Alelos , Animales , Brasil , Cartilla de ADN , Femenino , Sitios Genéticos , Genética de Población , Biblioteca Genómica , Genotipo , Heterocigoto , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Especificidad de la Especie
9.
Liver Int ; 40(4): 878-888, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31951082

RESUMEN

BACKGROUND & AIMS: Alcohol use disorder (AUD) represents the most common cause of liver disease. The gut microbiota plays a critical role in the progression of alcohol-related liver damage. Aim of this study was to characterize the gut microbial composition and function in AUD patients with alcohol-associated liver disease (AALD). METHODS: This study included 36 AUD patients (14 with cirrhosis) who were active drinkers and an equal number of matched controls. Stool microbial composition, serum levels of lipopolysaccharide, cytokines/chemokines and gut microbiota functional profile were assessed. RESULTS: AUD patients had a decreased microbial alpha diversity as compared to controls (0.092 vs 0.130, P = .047) and a specific gut microbial signature. The reduction of Akkermansia and the increase in Bacteroides were able to identify AUD patients with an accuracy of 93.4%. Serum levels of lipopolysaccharide (4.91 vs 2.43, P = .009) and pro-inflammatory mediators (tumour necrosis factor alpha 60.85 vs 15.08, P = .001; interleukin [IL] 1beta 4.43 vs 1.72, P = .0001; monocyte chemoattractant protein 1 225.22 vs 16.43, P = .006; IL6 1.87 vs 1.23, P = .008) were significantly increased in AUD patients compared to controls and in cirrhotic patients compared to non-cirrhotic ones (IL6 3.74 vs 1.39, P = .019; IL8 57.60 vs 6.53, P = .004). The AUD-associated gut microbiota showed an increased expression of gamma-aminobutyric acid (GABA) metabolic pathways and energy metabolism. CONCLUSIONS: AUD patients present a specific gut microbial fingerprint, associated with increased endotoxaemia, systemic inflammatory status and functional alterations that may be involved in the progression of the AALD and in the pathogenesis of AUD.


Asunto(s)
Alcoholismo , Microbioma Gastrointestinal , Hepatopatías Alcohólicas , Alcoholismo/complicaciones , Heces , Humanos , Cirrosis Hepática
10.
Anticancer Drugs ; 31(7): 709-717, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32639281

RESUMEN

Considering the high morbidity and mortality rates associated with hematological malignancies and the frequent development of drug resistance by these diseases, the search for new cytotoxic agents is an urgent necessity. The new compounds should present higher efficiency and specificity in inducing tumor cell death, be easily administered and have little or negligible adverse effects. Quinones have been reported in the literature by their several pharmacological properties, including antitumor activity, thus, the aim of this study was to investigate the cytotoxic effect of primin, a natural quinone, on hematological malignancies cell lines. Primin was highly cytotoxic against the three cell lines included in this study (K562, Jurkat and MM.1S) in a concentration- and time-dependent manner, as demonstrated by the MTT method. The compound triggered an apoptotic-like cell death, as observed by ethidium bromide/acridine orange staining, DNA fragmentation and phosphatidylserine exposure after labeling with Annexin V. Both intrinsic and extrinsic apoptosis are involved in cell death induced by primin, as well as the modulation of cell proliferation marker KI-67. The activation of intrinsic apoptosis appears to be related to a decreased Bcl-2 expression and increased Bax expression. While the increase in FasR expression signals activate extrinsic apoptosis. The results suggest that primin is a promising natural molecule that could be used in hematological malignancies therapy or as prototypes for the development of new chemotherapics.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Benzoquinonas/farmacología , Neoplasias Hematológicas/tratamiento farmacológico , Antineoplásicos Fitogénicos/efectos adversos , Antineoplásicos Fitogénicos/aislamiento & purificación , Apoptosis/efectos de los fármacos , Factor Inductor de la Apoptosis/metabolismo , Benzoquinonas/efectos adversos , Benzoquinonas/aislamiento & purificación , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Eugenia/química , Neoplasias Hematológicas/metabolismo , Neoplasias Hematológicas/patología , Humanos , Células Jurkat , Células K562 , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteína X Asociada a bcl-2/metabolismo
11.
World J Urol ; 38(1): 143-150, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30993426

RESUMEN

BACKGROUND: Basophils, eosinophils and monocytes may be involved in BCG-induced immune responses and be associated with outcomes of bladder cancer patients receiving intravesical BCG. Our objective was to explore the association of baseline counts of basophils, eosinophils and monocytes with outcomes of patients with high-grade T1 bladder cancer receiving a standard course of intravesical BCG. METHODS: We retrospectively reviewed medical records of patients with primary T1 HG/G3 bladder cancer. After re-TURBT, patients were treated with a 6-week course of intravesical BCG induction followed by intravesical BCG every week for 3 weeks given at 3, 6, 12, 18, 24, 30 and 36 months from initiation of therapy The analysis of potential risk factors for recurrence, muscle invasion and cancer-specific and overall survival was performed using univariable Cox regression models. Those factors that presented, at univariate analysis, an association with the event at a liberal p < 0.1, have been selected for the development of a multivariable model. RESULTS: A total of 1045 patients with primary T1 HG/G3 were included. A total of 678 (64.9%) recurrences, 303 (29.0%) progressions and 150 (14.3%) deaths were observed during follow-up. Multivariate analysis showed that logarithmic transformation of basophils count was associated with a 30% increment in the hazard of recurrence per unit increase of logarithmic basophils count (HR 1.30; 95% confidence interval 1.09-1.54; p = 0.0026). Basophil count modeled by quartiles was also significantly associated with time to recurrence [second vs. lower quartile HR 1.42 (1.12-1.79); p = 0.003, third vs. lower quartile HR 1.26 (1.01-1.57); p = 0.041; upper vs. lower quartile HR 1.36 (1.1-1.68); p = 0.005]. The limitations of a retrospective study are applicable. CONCLUSION: Baseline basophil count may predict recurrence in BCG-treated HG/G3 T1 bladder cancer patients. External validation is warranted.


Asunto(s)
Vacuna BCG/administración & dosificación , Basófilos/patología , Cistectomía/métodos , Recurrencia Local de Neoplasia/diagnóstico , Estadificación de Neoplasias/métodos , Neutrófilos/patología , Neoplasias de la Vejiga Urinaria/terapia , Adyuvantes Inmunológicos/administración & dosificación , Administración Intravesical , Adulto , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo , Neoplasias de la Vejiga Urinaria/patología
12.
Alcohol Alcohol ; 55(5): 547-553, 2020 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-32533164

RESUMEN

AIM: People experiencing homelessness are often excluded from treatment programs for alcohol use disorder (AUD). The goal of this study was to describe the impact of a multidisciplinary treatment program on alcohol consumption and social reintegration in individuals with AUD experiencing homelessness. METHODS: Thirty-one individuals with AUD experiencing homelessness were admitted to an inpatient unit for 5-6 days for clinical evaluation and to treat potential alcohol withdrawal syndrome. A group of volunteers, in collaboration with the Community of Sant'Egidio, provided social support aimed to reintegrate patients. After inpatient discharge, all patients were followed as outpatients. Alcohol intake (number drinks/day), craving and clinical evaluation were assessed at each outpatient visit. Biological markers of alcohol use were evaluated at enrollment (T0), at 6 months (T1) and 12 months (T2). RESULTS: Compared with T0, patients at T1 showed a significant reduction in alcohol consumption [10 (3-24) vs 2 (0-10); P = 0.015] and in γ-glutamyl-transpeptidase [187 (78-365) vs 98 (74-254); P = 0.0021]. The reduction in alcohol intake was more pronounced in patients with any housing condition [10 (3-20) vs 1 (0-8); P = 0.008]. Similarly, compared with T0, patients at T2 showed significant reduction in alcohol consumption [10 (3-24) vs 0 (0-15); P = 0.001], more pronounced in patients with any housing condition [10 (3-20) vs 0 (0-2); P = 0.006]. Moreover, at T2 patients showed a significant reduction in γ-glutamyl-transpeptidase [187 (78-365) vs 97 (74-189); P = 0.002] and in mean cell volume [100.2 (95-103.6) vs 98.3 (95-102); P = 0.042]. CONCLUSION: Patients experiencing homelessness may benefit from a multidisciplinary treatment program for AUD. Strategies able to facilitate and support their social reintegration and housing can improve treatment outcomes.


Asunto(s)
Alcoholismo/terapia , Personas con Mala Vivienda/psicología , Grupo de Atención al Paciente , Adulto , Consumo de Bebidas Alcohólicas/terapia , Alcoholismo/sangre , Ansia , Índices de Eritrocitos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sistemas de Apoyo Psicosocial , Apoyo Social , Síndrome de Abstinencia a Sustancias/rehabilitación , gamma-Glutamiltransferasa/sangre
13.
J Enzyme Inhib Med Chem ; 35(1): 31-41, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31645149

RESUMEN

The present study describes the synthesis of a novel series of thiazolidin-4-one and thiazinan-4-one using 1-(2-aminoethyl)pyrrolidine as amine precursor. All compounds were synthesised by one-pot three component cyclocondensation reaction from the amine, a substituted benzaldehyde and a mercaptocarboxylic acid. The compounds were obtained in moderate to good yields and were identified and characterised by 1H, 13 C, 2 D NMR and GC/MS techniques. The compounds also were screened for their in vitro acetylcholinesterase (AChE) activity in hippocampus and cerebral cortex on Wistar rats. The six most potent compounds have been investigated for their cytotoxicity by cell viability assay of astrocyte primary culture, an important cell of central nervous system. We highlighted two compounds (6a and 6k) that had the lowest IC50 in hippocampus (5.20 and 4.46 µM) and cerebral cortex (7.40 and 6.83 µM). These preliminary and important results could be considered a starting point for the development of new AChE inhibitory agents.


Asunto(s)
Acetilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/farmacología , Tiazinas/farmacología , Tiazolidinas/farmacología , Animales , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/enzimología , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/química , Relación Dosis-Respuesta a Droga , Hipocampo/efectos de los fármacos , Hipocampo/enzimología , Estructura Molecular , Ratas , Ratas Wistar , Relación Estructura-Actividad , Tiazinas/síntesis química , Tiazinas/química , Tiazolidinas/síntesis química , Tiazolidinas/química
14.
Pediatr Radiol ; 50(1): 28-37, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31583441

RESUMEN

BACKGROUND: The acquisition of chest radiographs in neonates is of critical importance in diagnostics because of the risk of respiratory distress syndrome and pneumothorax in preterm infants. OBJECTIVE: To achieve a dose reduction while preserving a diagnostic image quality for chest radiographs of neonates. MATERIALS AND METHODS: All radiographs, generated on a fully digital X-ray unit by using a neonatal chest phantom, were evaluated under variation of the tube voltage (40-70 kV) and mAs levels (1-10.2 mAs) with and without an additional 0.1-mm copper (Cu) filtration. Noise, contrast and contrast-to-noise ratio for bronchus, heart, lungs and vessels were determined. Visual assessment of the image quality was carried out by three radiologists using a Likert scale. To evaluate a maximally possible dose reduction, the dose of the radiographs with still acceptable image quality at a minimal dose was compared to the dose of the radiographs with the standard settings used in clinical routine. RESULTS: The noise showed decreasing values with increasing dose, while the contrast values were increased. For the contrast-to-noise ratio, a digressive course of the values as a function of the tube voltage was found. The visual evaluation of image quality showed the best evaluation of the structures at the lowest possible dose in the settings (44 kV, 3.36 mAs) with copper filtration and in the settings (44 kV, 1.56 mAs) without copper filtration. A maximum dose reduction from 8.29 µSv to 2.21 µSv (about 73%) was obtained. CONCLUSION: A dose reduction while preserving diagnostic image quality in a digital X-ray system is generally possible by reducing the tube voltage and simultaneous adaptation of the mAs settings.


Asunto(s)
Pulmón/diagnóstico por imagen , Fantasmas de Imagen , Dosis de Radiación , Radiografía Torácica/métodos , Humanos , Recién Nacido
15.
Radiologe ; 60(10): 959-965, 2020 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-32495008

RESUMEN

BACKGROUND: The entry of the new Radiation Protection Act and new Radiation Protection Regulation into force in Germany created many changes for radiology with regard to the old Radiation Protection Regulation and X­ray Regulation. OBJECTIVES: The substantial modifications in radiology regarding the areas of approval and notification procedures, teleradiology, screening, research and radon in the workplace are summarized. METHOD: Changes in the new Radiation Protection Act and Regulation compared to the old Radiation Protection Regulation and X­ray Regulation were evaluated. Thereby, the focus was on areas beyond the workflow in clinical routine. RESULTS AND CONCLUSION: The requirements for the approval and notification procedure have increased. For example, proof must be provided that a medical physics expert can be consulted. The establishment of deadlines for the process by the responsible authorities may accelerate the procedure and create planning certainty.


Asunto(s)
Protección Radiológica , Radiología , Telerradiología , Alemania , Humanos , Protección Radiológica/legislación & jurisprudencia , Radiografía
16.
Radiologe ; 60(8): 721-728, 2020 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-32495010

RESUMEN

BACKGROUND: On 31 December 2018, the new Radiation Protection Regulation came into effect in Germany and made the new Radiation Protection Act more concrete. The old Radiation Protection Regulation and X­ray Regulation have thereby been replaced. OBJECTIVES: The substantial modifications regarding the practical daily routine in radiology are summarized. METHODS: Modifications and innovations of the New Radiation Protection Act and Regulation compared to the old Radiation Protection Regulation and X­ray Regulation and accordances were evaluated. Thereby the main focus was in the relevance for workflow in clinical routine. RESULTS AND CONCLUSION: The new legislation contains a number of regulations that provide crucial tools for implementation of radiation protection, quality assurance, and dose optimization. However, this also requires additional time and personnel.


Asunto(s)
Protección Radiológica/legislación & jurisprudencia , Radiología/organización & administración , Flujo de Trabajo , Alemania , Humanos
17.
Mol Microbiol ; 110(5): 777-795, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30204278

RESUMEN

With increasing numbers of 3D structures of bacteriophage components, combined with powerful in silico predictive tools, it has become possible to decipher the structural assembly and associated functionality of phage adhesion devices. Recently, decorations have been reported in the tail and neck passage structures of members of the so-called 936 group of lactococcal siphophages. In the current report, using bioinformatic analysis we identified a conserved carbohydrate binding module (CBM) among many of the virion baseplate Dit components, in addition to the CBM present in the 'classical' receptor binding proteins (RBPs). We observed that, within these so-called 'evolved' Dit proteins, the identified CBMs have structurally conserved folds, yet can be grouped into four distinct classes. We expressed such modules in fusion with GFP, and demonstrated their binding capability to their specific host using fluorescent binding assays with confocal microscopy. We detected evolved Dits in several phages infecting various Gram-positive bacterial species, including mycobacteria. The omnipresence of CBM domains in siphophages indicates their auxiliary role in infection, as they can assist in the specific recognition of and attachment to their host, thus ensuring a highly efficient and specific phage-host adhesion process as a prelude to DNA injection.


Asunto(s)
Lactococcus lactis/virología , Siphoviridae/genética , Siphoviridae/metabolismo , Proteínas de la Cola de los Virus/genética , Virión/genética , Carbohidratos/química , Modelos Moleculares , Unión Proteica , Conformación Proteica
18.
Environ Microbiol ; 21(4): 1331-1343, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30680877

RESUMEN

Domestication of dogs from wolves is the oldest known example of ongoing animal selection, responsible for generating more than 300 dog breeds worldwide. In order to investigate the taxonomic and functional evolution of the canine gut microbiota, a multi-omics approach was applied to six wild wolves and 169 dog faecal samples, the latter encompassing 51 breeds, which fully covers currently known canine genetic biodiversity. Specifically, 16S rRNA gene and bifidobacterial Internally Transcribed Spacer (ITS) profiling were employed to reconstruct and then compare the canine core gut microbiota to those of wolves and humans, revealing that artificial selection and subsequent cohabitation of dogs with their owners influenced the microbial population of canine gut through loss and acquisition of specific bacterial taxa. Moreover, comparative analysis of the intestinal bacterial population of dogs fed on Bones and Raw Food (BARF) or commercial food (CF) diet, coupled with shotgun metagenomics, highlighted that both bacterial composition and metabolic repertoire of the canine gut microbiota have evolved to adapt to high-protein or high-carbohydrates intake. Altogether, these data indicate that artificial selection and domestication not only affected the canine genome, but also shaped extensively the bacterial population harboured by the canine gut.


Asunto(s)
Bacterias/clasificación , Bacterias/genética , Biodiversidad , Perros/microbiología , Microbioma Gastrointestinal/genética , Metagenoma/genética , Fenómenos Fisiológicos de la Nutrición , Animales , Bifidobacterium/genética , Heces/microbiología , Metagenómica , ARN Ribosómico 16S/genética , Lobos/microbiología
19.
Nucleic Acids Res ; 45(2): 902-914, 2017 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-27591253

RESUMEN

Alternative splicing of terminal exons increases transcript and protein diversity. How physiological and pathological stimuli regulate the choice between alternative terminal exons is, however, largely unknown. Here, we show that Brahma (BRM), the ATPase subunit of the hSWI/SNF chromatin-remodeling complex interacts with BRCA1/BARD1, which ubiquitinates the 50 kDa subunit of the 3' end processing factor CstF. This results in the inhibition of transcript cleavage at the proximal poly(A) site and a shift towards inclusion of the distal terminal exon. Upon oxidative stress, BRM is depleted, cleavage inhibition is released, and inclusion of the proximal last exon is favoored. Our findings elucidate a novel regulatory mechanism, distinct from the modulation of transcription elongation by BRM that controls alternative splicing of internal exons.


Asunto(s)
Empalme Alternativo , Proteína BRCA1/metabolismo , Factor de Estimulación del Desdoblamiento/metabolismo , Exones , Estrés Oxidativo , Transducción de Señal , Factores de Transcripción/metabolismo , Adenosina Trifosfatasas/metabolismo , Línea Celular Tumoral , Regulación de la Expresión Génica , Humanos , Complejos Multiproteicos , Estrés Oxidativo/genética , Poli A , Unión Proteica , Factores de Transcripción/genética , Ubiquitinación
20.
J Enzyme Inhib Med Chem ; 34(1): 197-203, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30482059

RESUMEN

A series of nineteen benzothiazin-4-ones from N-(3-aminopropyl) piperidine, 4-(2-aminoethyl)morpholine or 1-(2-aminoethyl)piperidine, aliphatic or aromatic aldehyde and thiosalicylic acid, were synthesized in good yields by multicomponent one-pot reactions. The solvent was toluene and this efficient procedure afforded the desired heterocycles in 5 h. Identification and characterization were achieved by NMR and GC-MS techniques. In vitro AChE activities of all compounds were evaluated in cerebral cortex and hippocampus of rats and in general, the results in cortex were more promising than hippocampus. The benzothiazinone 5Bd showed the best AChE inhibition activity IC50 8.48 µM (cortex) and IC50 39.80 µM (hippocampus). The cytotoxicity of seven compounds in MCR-5 human fibroblast cell by SRB test in 24 h were evaluated and 5Bd suggest preliminary safety, showing no cytotoxicity at 100 µM. Finally, these important findings could be a starting point for the development of new AChE inhibitors agents and will provide the basis for new studies.


Asunto(s)
Acetilcolinesterasa/metabolismo , Benzotiadiazinas/farmacología , Inhibidores de la Colinesterasa/farmacología , Animales , Benzotiadiazinas/síntesis química , Benzotiadiazinas/química , Células Cultivadas , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/química , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Fibroblastos/efectos de los fármacos , Humanos , Masculino , Estructura Molecular , Ratas , Ratas Wistar , Relación Estructura-Actividad
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