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1.
Nucleic Acids Res ; 51(17): 9214-9226, 2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37572349

RESUMEN

Bacteriophages and bacteria are engaged in a constant arms race, continually evolving new molecular tools to survive one another. To protect their genomic DNA from restriction enzymes, the most common bacterial defence systems, double-stranded DNA phages have evolved complex modifications that affect all four bases. This study focuses on modifications at position 7 of guanines. Eight derivatives of 7-deazaguanines were identified, including four previously unknown ones: 2'-deoxy-7-(methylamino)methyl-7-deazaguanine (mdPreQ1), 2'-deoxy-7-(formylamino)methyl-7-deazaguanine (fdPreQ1), 2'-deoxy-7-deazaguanine (dDG) and 2'-deoxy-7-carboxy-7-deazaguanine (dCDG). These modifications are inserted in DNA by a guanine transglycosylase named DpdA. Three subfamilies of DpdA had been previously characterized: bDpdA, DpdA1, and DpdA2. Two additional subfamilies were identified in this work: DpdA3, which allows for complete replacement of the guanines, and DpdA4, which is specific to archaeal viruses. Transglycosylases have now been identified in all phages and viruses carrying 7-deazaguanine modifications, indicating that the insertion of these modifications is a post-replication event. Three enzymes were predicted to be involved in the biosynthesis of these newly identified DNA modifications: 7-carboxy-7-deazaguanine decarboxylase (DpdL), dPreQ1 formyltransferase (DpdN) and dPreQ1 methyltransferase (DpdM), which was experimentally validated and harbors a unique fold not previously observed for nucleic acid methylases.


Asunto(s)
Bacteriófagos , Guanina , Bacterias/genética , Bacteriófagos/genética , ADN/genética , Guanina/análogos & derivados
2.
J Membr Biol ; 257(1-2): 79-89, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38436710

RESUMEN

The gastric H+,K+-ATPase is an integral membrane protein which derives energy from the hydrolysis of ATP to transport H+ ions from the parietal cells of the gastric mucosa into the stomach in exchange for K+ ions. It is responsible for the acidic environment of the stomach, which is essential for digestion. Acid secretion is regulated by the recruitment of the H+,K+-ATPase from intracellular stores into the plasma membrane on the ingestion of food. The similar amino acid sequences of the lysine-rich N-termini α-subunits of the H+,K+- and Na+,K+-ATPases, suggests similar acute regulation mechanisms, specifically, an electrostatic switch mechanism involving an interaction of the N-terminal tail with the surface of the surrounding membrane and a modulation of the interaction via regulatory phosphorylation by protein kinases. From a consideration of sequence alignment of the H+,K+-ATPase and an analysis of its coevolution with protein kinase C and kinases of the Src family, the evidence points towards a phosphorylation of tyrosine-7 of the N-terminus by either Lck or Yes in all vertebrates except cartilaginous fish. The results obtained will guide and focus future experimental research.


Asunto(s)
ATPasa Intercambiadora de Sodio-Potasio , Estómago , Animales , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Transporte Biológico , ATPasa Intercambiadora de Hidrógeno-Potásio/química , Iones/metabolismo
3.
Chemistry ; 30(15): e202303458, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38221142

RESUMEN

The recent discovery of blue fluorophores with high quantum yields based on pyridone structures inspired the development of new low-molecular-weight fluorophores with bright emissions at tunable wavelengths, which are highly attractive for various applications. In this study, we propose a rational design strategy for 2-pyridone-based fluorophores with bright emissions at long wavelengths. With a detailed understanding of the positional substitution effects on each carbon atom of the 2-pyridone core, we developed a bright blue fluorophore (λabs =377 nm; λem =433 nm; ϵ=13,200 M-1 cm-1 ; ϕF =88 %) through C3 -aryl and C4 -ester substitutions followed by cyclization. Furthermore, by applying the intramolecular charge transfer (ICT) principle, we invented a bright green fluorophore through C3 - and C4 -diester and C6 -aryl substitutions. The ICT fluorophore based on the pyridone structure shows large molar absorptivity (ϵ=20,100 M-1 cm-1 ), longer emission wavelength (λem =539 nm), high emission quantum yield (ϕF =74 %), and large Stokes shift (Δv=5720 cm-1 ), which are comparable to those of practical fluorescent probes.

4.
Brain Behav Immun ; 120: 413-429, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38925413

RESUMEN

Huntington's disease (HD) is a hereditary neurodegenerative disorder characterized by involuntary movements, cognitive deficits, and psychiatric symptoms. Currently, there is no cure, and only limited treatments are available to manage the symptoms and to slow down the disease's progression. The molecular and cellular mechanisms of HD's pathogenesis are complex, involving immune cell activation, altered protein turnover, and disturbance in brain energy homeostasis. Microglia have been known to play a dual role in HD, contributing to neurodegeneration through inflammation but also enacting neuroprotective effects by clearing mHTT aggregates. However, little is known about the contribution of microglial metabolism to HD progression. This study explores the impact of a microglial metabolite transporter, equilibrative nucleoside transporter 3 (ENT3), in HD. Known as a lysosomal membrane transporter protein, ENT3 is highly enriched in microglia, with its expression correlated with HD severity. Using the R6/2 ENT3-/- mouse model, we found that the deletion of ENT3 increases microglia numbers yet worsens HD progression, leading to mHTT accumulation, cell death, and disturbed energy metabolism. These results suggest that the delicate balance between microglial metabolism and function is crucial for maintaining brain homeostasis and that ENT3 has a protective role in ameliorating neurodegenerative processes.

5.
Transfusion ; 64(6): 1083-1096, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38644556

RESUMEN

BACKGROUND: Blood typing is essential for safe transfusions and is performed serologically or genetically. Genotyping predominantly focuses on coding regions, but non-coding variants may affect gene regulation, as demonstrated in the ABO, FY and XG systems. To uncover regulatory loci, we expanded a recently developed bioinformatics pipeline for discovery of non-coding variants by including additional epigenetic datasets. METHODS: Multiple datasets including ChIP-seq with erythroid transcription factors (TFs), histone modifications (H3K27ac, H3K4me1), and chromatin accessibility (ATAC-seq) were analyzed. Candidate regulatory regions were investigated for activity (luciferase assays) and TF binding (electrophoretic mobility shift assay, EMSA, and mass spectrometry, MS). RESULTS: In total, 814 potential regulatory sites in 47 blood-group-related genes were identified where one or more erythroid TFs bound. Enhancer candidates in CR1, EMP3, ABCB6, and ABCC4 indicated by ATAC-seq, histone markers, and co-occupancy of 4 TFs (GATA1/KLF1/RUNX1/NFE2) were investigated but only CR1 and ABCC4 showed increased transcription. Co-occupancy of GATA1 and KLF1 was observed in the KEL promoter, previously reported to contain GATA1 and Sp1 sites. TF binding energy scores decreased when three naturally occurring variants were introduced into GATA1 and KLF1 motifs. Two of three GATA1 sites and the KLF1 site were confirmed functionally. EMSA and MS demonstrated increased GATA1 and KLF1 binding to the wild-type compared to variant motifs. DISCUSSION: This combined bioinformatics and experimental approach revealed multiple candidate regulatory regions and predicted TF co-occupancy sites. The KEL promoter was characterized in detail, indicating that two adjacent GATA1 and KLF1 motifs are most crucial for transcription.


Asunto(s)
Antígenos de Grupos Sanguíneos , Epigénesis Genética , Humanos , Antígenos de Grupos Sanguíneos/genética , Factor de Transcripción GATA1/genética , Factores de Transcripción de Tipo Kruppel/genética , Secuencias Reguladoras de Ácidos Nucleicos/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
6.
Analyst ; 149(4): 1202-1211, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38214351

RESUMEN

In this study, the carboxy silane 4-(triethoxysilyl)butanoic acid (TESBA) was used to modify titanium dioxide (TiO2) to create a self-assembled monolayer (SAM) and then directionally immobilize a capture antibody using protein A. We selected the amino silane (3-aminopropyl)triethoxysilane (APTES) to perform a comparative analysis with TESBA, and employed glutaraldehyde (GA) as the control. The modification and detection effects and the limit of detection (LOD) were evaluated by detecting human immunoglobulin G (IgG). The average normalized sensitivity of the dual-grating coupler waveguide biosensor was 49.63 ± 0.27 RIU-1 and the optimum resolution was 1.30 × 10-6 RIU. When the SAM was prepared using TESBA and APTES followed by GA, the LOD was 4.59 × 10-7 g mL-1 and 5.29 × 10-7 g mL-1, respectively. We analyzed the modification and detection effects by the t-test and concluded that the differences in the modification effects using TESBA and APTES followed by GA were significant and the differences in the detection effects using TESBA and APTES followed by GA were insignificant. The use of TESBA as the SAM led to the modification effect being superior to that obtained using APTES followed by GA. The detection effect using TESBA was as outstanding as that using APTES followed by GA. Our findings demonstrate the feasibility and effectiveness of using TESBA as the SAM to carboxylate the surface of TiO2, thereby enabling immobilization of biomolecules for human IgG detection.


Asunto(s)
Inmunoglobulina G , Titanio , Humanos , Ácido Butírico , Glutaral
7.
Org Biomol Chem ; 22(8): 1646-1653, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38305467

RESUMEN

GaCl3-mediated one-pot cyclocondensation of o-allylbenzaldehydes and 1,3-dicarbonyls generates benzofused 8-oxabicyclo[3.3.1]nonanes in moderate to good yields in refluxing MeNO2 under easy-operational conditions. A plausible mechanism is proposed and discussed here. In the overall reaction process, various metal chloride-promoted conditions were investigated for one-pot cyclocondensation.

8.
Cereb Cortex ; 33(3): 676-690, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-35253866

RESUMEN

The amygdala is known to modulate hippocampal synaptic plasticity. One role could be an immediate effect of basolateral amygdala (BLA) in priming synaptic plasticity in the hippocampus. Another role could be through associative synaptic co-operation and competition that triggers events involved in the maintenance of synaptic potentiation. We present evidence that the timing and activity level of BLA stimulation are important factors for the induction and maintenance of long-term potentiation (LTP) in ventral hippocampal area CA1. A 100 Hz BLA co-stimulation facilitated the induction of LTP, whereas 200 Hz co-stimulation attenuated induction. A 100 Hz BLA co-stimulation also caused enhanced persistence, sufficient to prevent synaptic competition. This maintenance effect is likely through translational mechanisms, as mRNA expression of primary response genes was unaffected, whereas protein level of plasticity-related products was increased. Further understanding of the neural mechanisms of amygdala modulation on hippocampus could provide insights into the mechanisms of emotional disorders.


Asunto(s)
Complejo Nuclear Basolateral , Plasticidad Neuronal , Plasticidad Neuronal/fisiología , Hipocampo/fisiología , Potenciación a Largo Plazo/fisiología , Amígdala del Cerebelo/fisiología , Estimulación Eléctrica
9.
Am J Emerg Med ; 80: 87-90, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38520802

RESUMEN

OBJECTIVE: To describe the epidemiology and patterns of gymnastics-related Head & Neck trauma injuries using the NEISS database from 2001 to 2020. STUDY DESIGN AND SETTING: Cross-sectional analysis of a national database. METHODS: Gymnastics-related ED visits between 2001 and 2020 were queried from the NEISS database. Bivariate chi-squared analyses were used to compare injury demographics, location, type, and disposition. Fracture location was identified using the narrative description of each case and were divided into subtypes for further analysis. RESULTS: 1455 gymnastics-related head and neck traumatic injuries were identified. The majority were in females (65.8%). The most common presenting age group was pediatric (≤18 years) (92.7%), and the largest racial group was Caucasian (51.5%). Of all location subtypes, facial injuries were the most common presenting injury type overall (45.2%). Regarding injury types, lacerations were most common (36.8%), followed by dental injury (30.7%) and fractures (21.2%). The most common location of head and neck fractures was the nose (45.8%), followed by cervical spine (16.7%) and orbit (13.3%). The majority (95.7%) of gymnastics-related head and neck traumatic injuries presenting to the ED were treated and discharged. CONCLUSION: This study characterizes gymnastics-related head and neck injuries which is a topic that is under-studied. The findings from this study are helpful for gymnasts and those who care for them including providers, coaches and guardians, and this data may help inform future guidelines for treatment and injury prevention.


Asunto(s)
Traumatismos Craneocerebrales , Gimnasia , Traumatismos del Cuello , Humanos , Femenino , Masculino , Estudios Transversales , Niño , Traumatismos del Cuello/epidemiología , Adolescente , Adulto , Gimnasia/lesiones , Adulto Joven , Traumatismos Craneocerebrales/epidemiología , Estados Unidos/epidemiología , Bases de Datos Factuales , Servicio de Urgencia en Hospital/estadística & datos numéricos , Traumatismos en Atletas/epidemiología , Preescolar , Persona de Mediana Edad , Traumatismos Faciales/epidemiología , Traumatismos de los Dientes/epidemiología , Laceraciones/epidemiología
10.
Nucleic Acids Res ; 50(6): 3001-3017, 2022 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-34522950

RESUMEN

The DNAs of bacterial viruses are known to contain diverse, chemically complex modifications to thymidine that protect them from the endonuclease-based defenses of their cellular hosts, but whose biosynthetic origins are enigmatic. Up to half of thymidines in the Pseudomonas phage M6, the Salmonella phage ViI, and others, contain exotic chemical moieties synthesized through the post-replicative modification of 5-hydroxymethyluridine (5-hmdU). We have determined that these thymidine hypermodifications are derived from free amino acids enzymatically installed on 5-hmdU. These appended amino acids are further sculpted by various enzyme classes such as radical SAM isomerases, PLP-dependent decarboxylases, flavin-dependent lyases and acetyltransferases. The combinatorial permutations of thymidine hypermodification genes found in viral metagenomes from geographically widespread sources suggests an untapped reservoir of chemical diversity in DNA hypermodifications.


Asunto(s)
Bacteriófagos , Liasas , Aminoácidos/metabolismo , Bacteriófagos/genética , ADN/metabolismo , Timidina/metabolismo
11.
Proc Natl Acad Sci U S A ; 118(26)2021 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-34155108

RESUMEN

TET/JBP (ten-eleven translocation/base J binding protein) enzymes are iron(II)- and 2-oxo-glutarate-dependent dioxygenases that are found in all kingdoms of life and oxidize 5-methylpyrimidines on the polynucleotide level. Despite their prevalence, few examples have been biochemically characterized. Among those studied are the metazoan TET enzymes that oxidize 5-methylcytosine in DNA to hydroxy, formyl, and carboxy forms and the euglenozoa JBP dioxygenases that oxidize thymine in the first step of base J biosynthesis. Both enzymes have roles in epigenetic regulation. It has been hypothesized that all TET/JBPs have their ancestral origins in bacteriophages, but only eukaryotic orthologs have been described. Here we demonstrate the 5mC-dioxygenase activity of several phage TETs encoded within viral metagenomes. The clustering of these TETs in a phylogenetic tree correlates with the sequence specificity of their genomically cooccurring cytosine C5-methyltransferases, which install the methyl groups upon which TETs operate. The phage TETs favor Gp5mC dinucleotides over the 5mCpG sites targeted by the eukaryotic TETs and are found within gene clusters specifying complex cytosine modifications that may be important for DNA packaging and evasion of host restriction.


Asunto(s)
5-Metilcitosina/metabolismo , Bacteriófagos/metabolismo , ADN/metabolismo , Secuencia de Aminoácidos , Metilación de ADN , Dioxigenasas , Hidroxilación , Metagenómica , Motivos de Nucleótidos/genética , Oxidación-Reducción , Filogenia
12.
J Craniofac Surg ; 35(4): 1129-1133, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38688025

RESUMEN

Understanding rhinoplasty characteristics important to patients, physicians, and society is essential for evaluating outcomes and designing optimal treatment plans. The authors aimed to elucidate specific rhinoplasty-related outcomes that are most important to patients, surgeons, and the general population. A cross-sectional survey comprising 11 rhinoplasty-specific characteristics, was distributed to patients, facial plastic surgeons, and the general population. Adult patients presenting for rhinoplasty consideration or follow-up after undergoing rhinoplasty were recruited. Characteristics rankings were compared between the 3 respondent groups using Spearman's rank correlation coefficient (ρ). Responses from 150 surgeons, 111 patients, and 102 lay individuals from the general population were included for analysis. When ranking rhinoplasty-specific characteristics in order of importance, patients and the general population ranked "ability to breathe through nose while awake" first and "overall appearance of nose" as second. Surgeons ranked "overall appearance of nose" first and "ability to breathe through nose while awake" second. There were strong correlations between patients' and surgeons' rankings (Spearman's ρ=0.836, P =0.002), between patients' and the general population's rankings (Spearman's ρ=0.773, P =0.007), and between surgeons' and the general population's rankings (Spearman's ρ=0.782, P =0.006). Our results highlight a significant correlation between characteristics of the "ideal" nose as determined by patients, surgeons, and the general population.


Asunto(s)
Rinoplastia , Humanos , Femenino , Masculino , Estudios Transversales , Adulto , Persona de Mediana Edad , Cirujanos/estadística & datos numéricos , Encuestas y Cuestionarios , Resultado del Tratamiento , Satisfacción del Paciente , Estética
13.
Int J Cancer ; 153(4): 756-764, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37183319

RESUMEN

Our study investigated how adverse cardiovascular outcomes are impacted by cardiovascular comorbidities in patients with prostate cancer treated by androgen deprivation therapy (ADT). Using prospective, population-based data, all Hong Kong patients with prostate cancer who received ADT during 1 January 1993 to 3 March 2021 were identified and followed up for the endpoint of cardiovascular hospitalization/mortality until 31 September 2021, whichever earlier. Multivariable competing risk regression was used to compare the endpoint's cumulative incidence between different combinations of major cardiovascular comorbidities (heart failure [HF], myocardial infarction [MI], stroke and/or arrhythmia), with noncardiovascular death as competing event. Altogether, 13 537 patients were included (median age 75.9 [interquartile range 70.0-81.5] years old; median follow-up 3.3 [1.5-6.7] years). Compared to those with none of prior HF/MI/stroke/arrhythmia, the incidence of the endpoint was not different in those with only stroke (subhazard ratio [SHR] 1.06 [95% confidence interval (CI): 0.92-1.23], P = .391), but was higher in those with only HF (SHR 1.67 [1.37-2.02], P < .001), arrhythmia (SHR 1.63 [1.35-1.98], P < .001) or MI (SHR 1.43 [1.14-1.79], P = .002). Those with ≥2 of HF/MI/stroke/arrhythmia had the highest incidence of the endpoint (SHR 1.94 [1.62-2.33], P < .001), among whom different major cardiovascular comorbidities had similar prognostic impacts, with the number of comorbidities present being significantly prognostic instead. In conclusion, in patients with prostate cancer receiving ADT, the sole presence of HF, MI or arrhythmia, but not stroke, may be associated with elevated cardiovascular risks. In those with ≥2 of HF/MI/stroke/arrhythmia, the number of major cardiovascular comorbidities may be prognostically more important than the type of comorbidities.


Asunto(s)
Neoplasias de la Próstata , Masculino , Humanos , Anciano , Anciano de 80 o más Años , Neoplasias de la Próstata/complicaciones , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/epidemiología , Antagonistas de Andrógenos/efectos adversos , Andrógenos , Pronóstico , Estudios Prospectivos , Factores de Riesgo , Medición de Riesgo
14.
Prostate ; 83(1): 119-127, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36178848

RESUMEN

BACKGROUND: This study aims to examine the associations between metformin use concurrent with androgen deprivation therapy (ADT) and mortality risks in Asian, diabetic patients with prostate cancer (PCa). METHODS: This study identified diabetic adults with PCa receiving any ADT attending public hospitals in Hong Kong between December 1999 and March 2021 retrospectively, with follow-up until September 2021. Patients with <6 months of medical castration without subsequent bilateral orchidectomy, <6 months of concurrent metformin use and ADT, or missing baseline HbA1c were excluded. Metformin users had ≥180 days of concurrent metformin use and ADT, while non-users had no concurrent metformin use and ADT or never used metformin. The primary outcome was PCa-related mortality. The secondary outcome was all-cause mortality. The study used inverse probability treatment weighting to balance covariates. RESULTS: The analyzed cohort consisted of 1971 patients (1284 metformin users and 687 non-users; mean age 76.2 ± 7.8 years). Over a mean follow-up of 4.1 ± 3.2 years, metformin users had significantly lower risks of PCa-related mortality (weighted hazard ratio [wHR]: 0.49 [95% confidence interval, CI:  0.39-0.61], p < 0.001) and all-cause mortality (wHR 0.53 [0.46-0.61], p < 0.001), independent of diabetic control or status of chronic kidney disease. Such effects appeared stronger in patients with less advanced PCa, which is reflected by the absence of androgen receptor antagonist or chemotherapy use (p value for interaction: 0.017 for PCa-related mortality; 0.048 for all-cause mortality). CONCLUSIONS: Metformin use concurrent with ADT was associated with lower risks of mortality in Asian, diabetic patients with PCa.


Asunto(s)
Diabetes Mellitus , Metformina , Neoplasias de la Próstata , Masculino , Humanos , Anciano , Anciano de 80 o más Años , Metformina/uso terapéutico , Antagonistas de Andrógenos/efectos adversos , Andrógenos , Neoplasias de la Próstata/tratamiento farmacológico , Estudios Retrospectivos , Diabetes Mellitus/tratamiento farmacológico , Diabetes Mellitus/epidemiología
15.
Br J Cancer ; 128(12): 2253-2260, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37076564

RESUMEN

BACKGROUND: Although androgen deprivation therapy (ADT) is associated with cardiovascular risks, the extent and temporal trends of cardiovascular burden amongst patients with prostate cancer receiving ADT are unclear. METHODS: This retrospective cohort study analyzed adults with PCa receiving ADT between 1993-2021 in Hong Kong, with follow-up until 31/9/2021 for the primary outcome of major adverse cardiovascular events (MACE; composite of cardiovascular mortality, myocardial infarction, stroke, and heart failure), and the secondary outcome of mortality. Patients were stratified into four groups by the year of ADT initiation for comparisons. RESULTS: Altogether, 13,537 patients were included (mean age 75.5 ± 8.5 years old; mean follow-up 4.7 ± 4.3 years). More recent recipients of ADT had more cardiovascular risk factors and used more cardiovascular or antidiabetic medications. More recent recipients of ADT had higher risk of MACE (most recent (2015-2021) vs least recent (1993-2000) group: hazard ratio 1.33 [1.11, 1.59], P = 0.002; Ptrend < 0.001), but lower risk of mortality (hazard ratio 0.76 [0.70, 0.83], P < 0.001; Ptrend < 0.001). The 5-year risk of MACE and mortality for the most recent group were 22.5% [20.9%, 24.2%] and 52.9% [51.3%, 54.6%], respectively. CONCLUSIONS: Cardiovascular risk factors were increasingly prevalent amongst patients with prostate cancer receiving ADT, with increasing risk of MACE despite decreasing mortality.


Asunto(s)
Neoplasias de la Próstata , Masculino , Adulto , Humanos , Anciano , Anciano de 80 o más Años , Antagonistas de Andrógenos/efectos adversos , Andrógenos , Estudios de Cohortes , Estudios Retrospectivos
16.
Appl Environ Microbiol ; 89(9): e0062323, 2023 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-37668405

RESUMEN

Bacteriophages (phages) outnumber bacteria ten-to-one and cause infections at a rate of 1025 per second. The ability of phages to reduce bacterial populations makes them attractive alternative antibacterials for use in combating the rise in antimicrobial resistance. This effort may be hindered due to bacterial defenses such as Bacteriophage Exclusion (BREX) that have arisen from the constant evolutionary battle between bacteria and phages. For phages to be widely accepted as therapeutics in Western medicine, more must be understood about bacteria-phage interactions and the outcomes of bacterial phage defense. Here, we present the annotated genomes of 12 novel bacteriophage species isolated from water sources in Durham, UK, during undergraduate practical classes. The collection includes diverse species from across known phylogenetic groups. Comparative analyses of two novel phages from the collection suggest they may be founding members of a new genus. Using this Durham phage collection, we determined that particular BREX defense systems were likely to confer a varied degree of resistance against an invading phage. We concluded that the number of BREX target motifs encoded in the phage genome was not proportional to the degree of susceptibility. IMPORTANCE Bacteriophages have long been the source of tools for biotechnology that are in everyday use in molecular biology research laboratories worldwide. Phages make attractive new targets for the development of novel antimicrobials. While the number of phage genome depositions has increased in recent years, the expected bacteriophage diversity remains underrepresented. Here we demonstrate how undergraduates can contribute to the identification of novel phages and that a single City in England can provide ample phage diversity and the opportunity to find novel technologies. Moreover, we demonstrate that the interactions and intricacies of the interplay between bacterial phage defense systems such as Bacteriophage Exclusion (BREX) and phages are more complex than originally thought. Further work will be required in the field before the dynamic interactions between phages and bacterial defense systems are fully understood and integrated with novel phage therapies.


Asunto(s)
Bacteriófagos , Bacteriófagos/fisiología , Filogenia , Evolución Biológica , Bacterias , Inglaterra
17.
Foodborne Pathog Dis ; 20(8): 343-350, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37410536

RESUMEN

Uropathogenic Escherichia coli (UPEC) is known to cause 65-75% of human urinary tract infection (UTI) cases. Poultry meat is a reservoir of UPEC, which is suspected to cause foodborne UTIs. In the present study, we aimed to determine the growth potential of UPEC in ready-to-eat chicken breasts prepared by sous-vide processing. Four reference strains isolated from the urine of UTI patients (Bioresource Collection and Research Center [BCRC] 10,675, 15,480, 15,483, and 17,383) were tested by polymerase chain reaction assay for related genes to identify their phylogenetic type and UPEC specificity. A cocktail of these UPEC strains was inoculated into sous-vide cooked chicken breast at 103-4 colony-forming unit (CFU)/g and stored at 4°C, 10°C, 15°C, 20°C, 30°C, and 40°C. Changes in the populations of UPEC during storage were analyzed by a one-step kinetic analysis method using the U.S. Department of Agriculture [USDA] Integrated Pathogen Modeling Program-Global Fit [IPMP-Global Fit]. The results showed that the combination of the no lag phase primary model and the Huang square-root secondary model fitted well with the growth curves to obtain the appropriate kinetic parameters. This combination for predicting UPEC growth kinetics was further validated using it to study additional growth curves at 25°C and 37°C, which showed that the root mean square error, bias factor, and accuracy factor were 0.49-0.59 (log CFU/g), 0.941-0.984, and 1.056-1.063, respectively. In conclusion, the models developed in this study are acceptable and can be used to predict the growth of UPEC in sous-vide chicken breast.


Asunto(s)
Pollos , Comida Rápida , Almacenamiento de Alimentos , Carne , Escherichia coli Uropatógena , Pollos/microbiología , Comida Rápida/microbiología , Cinética , Carne/microbiología , Modelos Biológicos , Temperatura , Escherichia coli Uropatógena/clasificación , Escherichia coli Uropatógena/crecimiento & desarrollo , Animales
18.
Ophthalmic Plast Reconstr Surg ; 39(4): 316-327, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36692957

RESUMEN

PURPOSE: To present the clinical course of a patient with recurrent NK/T-cell lymphoma (NKTL) involving the orbit and to review the literature on patients with NKTL involving the orbit. METHODS: The PubMed database was searched for all cases of NKTL involving orbital, intraocular, or adnexal ocular structures. RESULTS: Ninety-six patients were included in the final analysis. The mean age of diagnosis was 48.1 ± 16.8 years. The patients were 53/96 (55.2%) male and 43/96 (44.8%) female. Tumor location varied and included the orbit in 80/96 (83.3%), nasosinus in 56/96 (58.3%), uvea in 11/96 (11.5%), lacrimal gland in 9/96 (9.4%), lacrimal drainage system in 11/96 (11.5%), and conjunctiva in 7/96 (7.3%) cases. Management included surgical debulking in 29/96 (30.2%) cases, radiotherapy in 52/96 (54.2%) cases, and chemotherapy in 82/96 (85.4%) cases. Median survival was 6 months (95% CI: 5-9). Chemotherapy (hazard ratio = 0.80, 95% CI: 0.67-0.95, p = 0.013), radiotherapy (hazard ratio = 0.75, 95% CI: 0.64-0.87, p < 0.001), and orbital involvement being a recurrence of disease (hazard ratio = 0.79, 95% CI: 0.67-0.95, p = 0.009) were associated with improved survival. Advanced Ann Arbor stage (III-IV) at diagnosis (hazard ratio = 1.22, 95% CI: 1.08-1.38, p = 0.001), vision loss (hazard ratio = 1.18, 95% CI: 1.04-1.34, p = 0.009), proptosis (hazard ratio = 1.15, 95% CI: 1.01-1.30, p = 0.035) and periorbital swelling (hazard ratio = 1.15, 95% CI: 1.00-1.33, p = 0.048) were associated with poor survival. CONCLUSIONS: NK/T-cell lymphoma involving the orbit, globe, or ocular adnexa heralds a poor prognosis where early diagnosis and therapy are critical. The use of radiotherapy and chemotherapy is associated with improved survival.


Asunto(s)
Aparato Lagrimal , Linfoma de Células T , Neoplasias Orbitales , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Neoplasias Orbitales/diagnóstico , Neoplasias Orbitales/terapia , Estudios Retrospectivos , Recurrencia Local de Neoplasia , Linfoma de Células T/diagnóstico , Linfoma de Células T/terapia , Aparato Lagrimal/patología
19.
Int J Mol Sci ; 24(7)2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-37047769

RESUMEN

Parkinson's disease (PD) is a neurodegenerative disease characterized by motor deficits and marked neuroinflammation in various brain regions. The pathophysiology of PD is complex and mounting evidence has suggested an association with the dysregulation of microRNAs (miRNAs) and gut dysbiosis. Using a rotenone-induced PD mouse model, we observed that administration of Lactobacillus plantarum PS128 (PS128) significantly improved motor deficits in PD-like mice, accompanied by an increased level of dopamine, reduced dopaminergic neuron loss, reduced microglial activation, reduced levels of inflammatory factors, and enhanced expression of neurotrophic factor in the brain. Notably, the inflammation-related expression of miR-155-5p was significantly upregulated in the proximal colon, midbrain, and striatum of PD-like mice. PS128 reduced the level of miR-155-5p, whereas it increased the expression of suppressor of cytokine signaling 1 (SOCS1), a direct target of miR-155-5p and a critical inhibitor of the inflammatory response in the brain. Alteration of the fecal microbiota in PD-like mice was partially restored by PS128 administration. Among them, Bifidobacterium, Ruminiclostridium_6, Bacteroides, and Alistipes were statistically correlated with the improvement of rotenone-induced motor deficits and the expression of miR-155-5p and SOCS1. Our findings suggested that PS128 ameliorates motor deficits and exerts neuroprotective effects by regulating the gut microbiota and miR-155-5p/SOCS1 pathway in rotenone-induced PD-like mice.


Asunto(s)
Microbioma Gastrointestinal , Lactobacillus plantarum , MicroARNs , Enfermedades Neurodegenerativas , Fármacos Neuroprotectores , Enfermedad de Parkinson , Ratones , Animales , Enfermedad de Parkinson/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Lactobacillus plantarum/metabolismo , Rotenona , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL
20.
Prostate ; 82(15): 1477-1480, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35915869

RESUMEN

BACKGROUND: Although androgen deprivation therapy has known cardiovascular risks, it is unclear if its duration is related to cardiovascular risks. This study thus aimed to investigate the associations between gonadotrophin-releasing hormone (GnRH) agonist use duration and cardiovascular risks. METHODS: This retrospective cohort study included adult patients with prostate cancer receiving GnRH agonists in Hong Kong during 1999-2021. Patients who switched to GnRH antagonists, underwent bilateral orchidectomy, had <6 months of GnRH agonist, prior myocardial infarction (MI), or prior stroke was excluded. All patients were followed up until September 2021 for a composite endpoint of MI and stroke. Multivariable competing-risk regression using the Fine-Gray subdistribution model was used, with mortality from any cause as the competing event. RESULTS: In total, 4038 patients were analyzed (median age 74.9 years old, interquartile range (IQR) 68.7-80.8 years old). Over a median follow-up of 4.1 years (IQR 2.1-7.5 years), longer GnRH agonists use was associated with higher risk of the endpoint (sub-hazard ratio per year 1.04 [1.01-1.06], p = 0.001), with those using GnRH agonists for ≥2 years having an estimated 23% increase in the sub-hazard of the endpoint (sub-hazard ratio 1.23 [1.04-1.46], p = 0.017). CONCLUSION: Longer GnRH agonist use may be associated with greater cardiovascular risks.


Asunto(s)
Neoplasias de la Próstata , Accidente Cerebrovascular , Adulto , Anciano , Anciano de 80 o más Años , Antagonistas de Andrógenos , Andrógenos , Hormona Liberadora de Gonadotropina , Humanos , Masculino , Estudios Retrospectivos , Medición de Riesgo , Accidente Cerebrovascular/inducido químicamente , Accidente Cerebrovascular/epidemiología
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