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1.
Immunity ; 54(9): 1976-1988.e7, 2021 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-34525338

RESUMEN

Mutations in the adenosine-to-inosine RNA-editing enzyme ADAR1 p150, including point mutations in the Z-RNA recognition domain Zα, are associated with Aicardi-Goutières syndrome (AGS). Here, we examined the in vivo relevance of ADAR1 binding of Z-RNA. Mutation of W197 in Zα, which abolished Z-RNA binding, reduced RNA editing. Adar1W197A/W197A mice displayed severe growth retardation after birth, broad expression of interferon-stimulated genes (ISGs), and abnormal development of multiple organs. Notably, malformation of the brain was accompanied by white matter vacuolation and gliosis, reminiscent of AGS-associated encephalopathy. Concurrent deletion of the double-stranded RNA sensor MDA5 ameliorated these abnormalities. ADAR1 (W197A) expression increased in a feedback manner downstream of type I interferons, resulting in increased RNA editing at a subset of, but not all, ADAR1 target sites. This increased expression did not ameliorate inflammation in Adar1W197A/W197A mice. Thus, editing of select endogenous RNAs by ADAR1 is essential for preventing inappropriate MDA5-mediated inflammation, with relevance to the pathogenesis of AGS.


Asunto(s)
Adenosina Desaminasa/genética , Enfermedades Autoinmunes del Sistema Nervioso/genética , Malformaciones del Sistema Nervioso/genética , Edición de ARN/genética , ARN Bicatenario/genética , Adenosina Desaminasa/metabolismo , Animales , Enfermedades Autoinmunes del Sistema Nervioso/fisiopatología , Modelos Animales de Enfermedad , Helicasa Inducida por Interferón IFIH1/metabolismo , Ratones , Mutación , Malformaciones del Sistema Nervioso/fisiopatología , ARN Bicatenario/metabolismo
2.
J Biol Chem ; 299(7): 104840, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37209819

RESUMEN

Adenosine-to-inosine RNA editing is catalyzed by nuclear adenosine deaminase acting on RNA 1 (ADAR1) p110 and ADAR2, and cytoplasmic ADAR1 p150 in mammals, all of which recognize dsRNAs as targets. RNA editing occurs in some coding regions, which alters protein functions by exchanging amino acid sequences, and is therefore physiologically significant. In general, such coding sites are edited by ADAR1 p110 and ADAR2 before splicing, given that the corresponding exon forms a dsRNA structure with an adjacent intron. We previously found that RNA editing at two coding sites of antizyme inhibitor 1 (AZIN1) is sustained in Adar1 p110/Aadr2 double KO mice. However, the molecular mechanisms underlying RNA editing of AZIN1 remain unknown. Here, we showed that Azin1 editing levels were increased upon type I interferon treatment, which activated Adar1 p150 transcription, in mouse Raw 264.7 cells. Azin1 RNA editing was observed in mature mRNA but not precursor mRNA. Furthermore, we revealed that the two coding sites were editable only by ADAR1 p150 in both mouse Raw 264.7 and human embryonic kidney 293T cells. This unique editing was achieved by forming a dsRNA structure with a downstream exon after splicing, and the intervening intron suppressed RNA editing. Therefore, deletion of a nuclear export signal from ADAR1 p150, shifting its localization to the nucleus, decreased Azin1 editing levels. Finally, we demonstrated that Azin1 RNA editing was completely absent in Adar1 p150 KO mice. Thus, these findings indicate that RNA editing of AZIN1 coding sites is exceptionally catalyzed by ADAR1 p150 after splicing.


Asunto(s)
Adenosina Desaminasa , Proteínas Portadoras , Edición de ARN , Animales , Humanos , Ratones , Adenosina Desaminasa/metabolismo , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Catálisis , Edición de ARN/efectos de los fármacos , Edición de ARN/genética , ARN Bicatenario/genética , ARN Mensajero/metabolismo , Células HEK293 , Ratones Noqueados , Células RAW 264.7 , Interferones/farmacología , Transporte de Proteínas
3.
Brief Bioinform ; 23(1)2022 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-34601552

RESUMEN

RNA structural elements called pseudoknots are involved in various biological phenomena including ribosomal frameshifts. Because it is infeasible to construct an efficiently computable secondary structure model including pseudoknots, secondary structure prediction methods considering pseudoknots are not yet widely available. We developed IPknot, which uses heuristics to speed up computations, but it has remained difficult to apply it to long sequences, such as messenger RNA and viral RNA, because it requires cubic computational time with respect to sequence length and has threshold parameters that need to be manually adjusted. Here, we propose an improvement of IPknot that enables calculation in linear time by employing the LinearPartition model and automatically selects the optimal threshold parameters based on the pseudo-expected accuracy. In addition, IPknot showed favorable prediction accuracy across a wide range of conditions in our exhaustive benchmarking, not only for single sequences but also for multiple alignments.


Asunto(s)
Algoritmos , ARN , Conformación de Ácido Nucleico , Estructura Secundaria de Proteína , ARN/química , ARN/genética , Análisis de Secuencia de ARN/métodos
4.
PLoS Genet ; 17(5): e1009516, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33983932

RESUMEN

Adenosine deaminase acting on RNA 1 (ADAR1), an enzyme responsible for adenosine-to-inosine RNA editing, is composed of two isoforms: nuclear p110 and cytoplasmic p150. Deletion of Adar1 or Adar1 p150 genes in mice results in embryonic lethality with overexpression of interferon-stimulating genes (ISGs), caused by the aberrant recognition of unedited endogenous transcripts by melanoma differentiation-associated protein 5 (MDA5). However, among numerous RNA editing sites, how many RNA sites require editing, especially by ADAR1 p150, to avoid MDA5 activation and whether ADAR1 p110 contributes to this function remains elusive. In particular, ADAR1 p110 is abundant in the mouse brain where a subtle amount of ADAR1 p150 is expressed, whereas ADAR1 mutations cause Aicardi-Goutières syndrome, in which the brain is one of the most affected organs accompanied by the elevated expression of ISGs. Therefore, understanding RNA editing-mediated prevention of MDA5 activation in the brain is especially important. Here, we established Adar1 p110-specific knockout mice, in which the upregulated expression of ISGs was not observed. This result suggests that ADAR1 p150-mediated RNA editing is enough to suppress MDA5 activation. Therefore, we further created Adar1 p110/Adar2 double knockout mice to identify ADAR1 p150-mediated editing sites. This analysis demonstrated that although the elevated expression of ISGs was not observed, only less than 2% of editing sites were preserved in the brains of Adar1 p110/Adar2 double knockout mice. Of note, we found that some sites were highly edited, which was comparable to those found in wild-type mice, indicating the presence of ADAR1 p150-specific sites. These data suggest that RNA editing at a very limited sites, which is mediated by a subtle amount of ADAR1 p150, is sufficient to prevents MDA5 activation, at least in the mouse brain.


Asunto(s)
Adenosina Desaminasa/metabolismo , Encéfalo/metabolismo , Helicasa Inducida por Interferón IFIH1/metabolismo , Edición de ARN , Regiones no Traducidas 3'/genética , Adenosina Desaminasa/deficiencia , Adenosina Desaminasa/genética , Animales , Animales Recién Nacidos , Femenino , Intrones/genética , Isoenzimas/metabolismo , Ratones , Ratones Noqueados , Mutación , Especificidad de Órganos , Proteínas de Unión al ARN/genética , Tasa de Supervivencia
5.
Int J Urol ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38634354

RESUMEN

OBJECTIVES: We report the first prospective trial of prostatic urethral lift for the treatment of lower urinary tract symptoms associated with benign prostatic hyperplasia in Japan. METHODS: This prospective study was conducted at a single institution and included patients with benign prostatic hyperplasia who underwent prostatic urethral lift based on the Japanese surgical indication. The primary efficacy endpoint was reduced international prostatic symptoms score in the early postoperative period after prostatic urethral lift. To assess efficacy, international prostatic symptoms score, quality of life, sexual health inventory for men, and uroflowmetry were evaluated 2 weeks before, 2 weeks after, and 6 weeks after surgery. RESULTS: We enrolled 120 elderly men. The patients experienced significantly reduced international prostatic symptoms scores from 15 at the baseline to 13 at 2 weeks, and to 10 at 6 weeks, respectively. The peak flow rates did not change significantly at any time point. Three patients had serious adverse events of grade 3a in the Clavien-Dindo classification. Four patients were evaluated for sexual function, and none had ejaculatory dysfunction. CONCLUSION: In the Japanese population, prostatic urethral lift is reliably performed under local anesthesia and rapidly improves symptoms.

6.
J UOEH ; 46(2): 227-239, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38839291

RESUMEN

The need for improved nutrition in older adults requiring care has been acknowledged, but, to the best of our knowledge, there is a lack of systematic review and integration of nutritional care studies with older adults in nursing homes. This scoping review aimed to examine the scope and nature of nutritional care research for older adults in nursing homes and to identify research gaps, following the guidelines of the Joanna Briggs Institute. We found varied nutritional care for older adults living in nursing homes, including individualized sessions, such as nutrition counseling, the addition of foods and preparations for increased nutritional intake, and the maintenance of an eating environment, such as feeding assistance and calling. The nutritional care identified in this scoping review also included studies that have improved the nutritional status of older adults in nursing homes by implementing educational programs for care staff. For future research on effective nutritional care for older adults in nursing homes, we suggest evaluating both short- and long-term intervention effects with an adequate sample size.


Asunto(s)
Casas de Salud , Estado Nutricional , Humanos , Anciano , Terapia Nutricional
7.
J Toxicol Pathol ; 37(3): 127-131, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38962258

RESUMEN

Duplicate testes lined in series were observed in the right scrotum of a 6-week-old Sprague-Dawley rat in a single-dose toxicity study. Of the two right testicles, one was spherical and less than half the size of a normal testis. The other was oval-shaped, slightly smaller than a normal testis, and possessed clear, tortuous blood vessels similar to those of a normal testis. Each right testis was grossly separated but faced the intertesticular adipose tissue and was sparsely joined by thin cord-like structures. Only one epididymis covered or encompassed the two right testes. The caput epididymis was attached to the smaller spherical testis, whereas the cauda epididymis was attached to the oval testis. Histopathological examination revealed that the smaller spherical testis on the right side and the testis on the left side were normal. The oval-shaped testis on the right exhibited markedly dilated degenerative seminiferous tubules with one to two layers of Sertoli or germ cells, and almost no spermatogenesis was observed. Multinucleated germ cells were observed in the lumen of the degenerated seminiferous tubules. The right epididymis was morphologically normal and contained few sperm in the epididymal duct of the tail. The cord-like structures between duplicate testes comprised fibrous and adipose tissues. Single efferent ductules, ectopic cartilage, and skeletal muscle tissues were buried in the adipose tissue. To our knowledge, this is the first report of spontaneous polyorchidism in a rodent.

8.
J Med Virol ; 95(1): e28110, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36042577

RESUMEN

Although urine and bladder washing samples are commonly used for the cytological evaluation of the bladder mucosa, it has been unknown whether these samples are likely suitable to investigate human papillomavirus (HPV) prevalence in the urinary bladder. The present study aimed to elucidate the appropriateness of spontaneously voided urine or bladder washing in screening HPV infection in the urinary bladder. Urine and bladder washing samples were obtained from 201 patients who underwent transurethral bladder tumor resection. After extracting DNA from both samples, HPV-DNA was examined using a nested polymerase chain reaction with GP5+/6+ and MY09/11 primers. HPV genotyping was performed in the HPV-positive samples. In situ hybridization (ISH) was performed to observe the HPV-DNA localization in urothelial cells among cytological samples and paraffin-embedded tumor tissues in HPV-positive washing samples. HPV prevalence in urine and washing samples were 9.5% and 7.0%, respectively. High-risk HPV prevalence in urine and washing samples was 7.5% and 4.0%, respectively. The most common HPV type was HPV 16, followed by HPV 52 and HPV 18 in both samples. HPV type distribution in both samples was not in agreement (κ = -0.431). The ISH analysis revealed that HPV-DNA signal was observed in urothelial cells of five (55.7%) of nine detectable HPV-positive cytological samples. Six (66.7%) of nine HPV-positive cases had HPV-DNA signals in tumor tissue. The use of washing samples was likely applicable for investigating HPV prevalence in the urinary bladder. HPV-DNA detected in washing samples might be frequently derived from the urinary bladder.


Asunto(s)
Infecciones por Papillomavirus , Neoplasias de la Vejiga Urinaria , Humanos , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/patología , Virus del Papiloma Humano , Vejiga Urinaria/química , Vejiga Urinaria/patología , Prevalencia , Papillomaviridae/genética , ADN Viral/genética , ADN Viral/análisis , Neoplasias de la Vejiga Urinaria/patología
9.
Eur Radiol ; 33(12): 8488-8500, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37432405

RESUMEN

OBJECTIVES: To evaluate the effect of super-resolution deep-learning-based reconstruction (SR-DLR) on the image quality of coronary CT angiography (CCTA). METHODS: Forty-one patients who underwent CCTA using a 320-row scanner were retrospectively included. Images were reconstructed with hybrid (HIR), model-based iterative reconstruction (MBIR), normal-resolution deep-learning-based reconstruction (NR-DLR), and SR-DLR algorithms. For each image series, image noise, and contrast-to-noise ratio (CNR) at the left main trunk, right coronary artery, left anterior descending artery, and left circumflex artery were quantified. Blooming artifacts from calcified plaques were measured. Image sharpness, noise magnitude, noise texture, edge smoothness, overall quality, and delineation of the coronary wall, calcified and noncalcified plaques, cardiac muscle, and valves were subjectively ranked on a 4-point scale (1, worst; 4, best). The quantitative parameters and subjective scores were compared among the four reconstructions. Task-based image quality was assessed with a physical evaluation phantom. The detectability index for the objects simulating the coronary lumen, calcified plaques, and noncalcified plaques was calculated from the noise power spectrum (NPS) and task-based transfer function (TTF). RESULTS: SR-DLR yielded significantly lower image noise and blooming artifacts with higher CNR than HIR, MBIR, and NR-DLR (all p < 0.001). The best subjective scores for all the evaluation criteria were attained with SR-DLR, with significant differences from all other reconstructions (p < 0.001). In the phantom study, SR-DLR provided the highest NPS average frequency, TTF50%, and detectability for all task objects. CONCLUSION: SR-DLR considerably improved the subjective and objective image qualities and object detectability of CCTA relative to HIR, MBIR, and NR-DLR algorithms. CLINICAL RELEVANCE STATEMENT: The novel SR-DLR algorithm has the potential to facilitate accurate assessment of coronary artery disease on CCTA by providing excellent image quality in terms of spatial resolution, noise characteristics, and object detectability. KEY POINTS: • SR-DLR designed for CCTA improved image sharpness, noise property, and delineation of cardiac structures with reduced blooming artifacts from calcified plaques relative to HIR, MBIR, and NR-DLR. • In the task-based image-quality assessments, SR-DLR yielded better spatial resolution, noise property, and detectability for objects simulating the coronary lumen, coronary calcifications, and noncalcified plaques than other reconstruction techniques. • The image reconstruction times of SR-DLR were shorter than those of MBIR, potentially serving as a novel standard-of-care reconstruction technique for CCTA performed on a 320-row CT scanner.


Asunto(s)
Aprendizaje Profundo , Placa Aterosclerótica , Humanos , Angiografía por Tomografía Computarizada , Estudios Retrospectivos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Dosis de Radiación , Tomografía Computarizada por Rayos X/métodos , Angiografía Coronaria , Algoritmos
10.
Eur Radiol ; 33(5): 3253-3265, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36973431

RESUMEN

OBJECTIVES: To evaluate the image quality of deep learning-based reconstruction (DLR), model-based (MBIR), and hybrid iterative reconstruction (HIR) algorithms for lower-dose (LD) unenhanced head CT and compare it with those of standard-dose (STD) HIR images. METHODS: This retrospective study included 114 patients who underwent unenhanced head CT using the STD (n = 57) or LD (n = 57) protocol on a 320-row CT. STD images were reconstructed with HIR; LD images were reconstructed with HIR (LD-HIR), MBIR (LD-MBIR), and DLR (LD-DLR). The image noise, gray and white matter (GM-WM) contrast, and contrast-to-noise ratio (CNR) at the basal ganglia and posterior fossa levels were quantified. The noise magnitude, noise texture, GM-WM contrast, image sharpness, streak artifact, and subjective acceptability were independently scored by three radiologists (1 = worst, 5 = best). The lesion conspicuity of LD-HIR, LD-MBIR, and LD-DLR was ranked through side-by-side assessments (1 = worst, 3 = best). Reconstruction times of three algorithms were measured. RESULTS: The effective dose of LD was 25% lower than that of STD. Lower image noise, higher GM-WM contrast, and higher CNR were observed in LD-DLR and LD-MBIR than those in STD (all, p ≤ 0.035). Compared with STD, the noise texture, image sharpness, and subjective acceptability were inferior for LD-MBIR and superior for LD-DLR (all, p < 0.001). The lesion conspicuity of LD-DLR (2.9 ± 0.2) was higher than that of HIR (1.2 ± 0.3) and MBIR (1.8 ± 0.4) (all, p < 0.001). Reconstruction times of HIR, MBIR, and DLR were 11 ± 1, 319 ± 17, and 24 ± 1 s, respectively. CONCLUSION: DLR can enhance the image quality of head CT while preserving low radiation dose level and short reconstruction time. KEY POINTS: • For unenhanced head CT, DLR reduced the image noise and improved the GM-WM contrast and lesion delineation without sacrificing the natural noise texture and image sharpness relative to HIR. • The subjective and objective image quality of DLR was better than that of HIR even at 25% reduced dose without considerably increasing the image reconstruction times (24 s vs. 11 s). • Despite the strong noise reduction and improved GM-WM contrast performance, MBIR degraded the noise texture, sharpness, and subjective acceptance with prolonged reconstruction times relative to HIR, potentially hampering its feasibility.


Asunto(s)
Interpretación de Imagen Radiográfica Asistida por Computador , Tomografía Computarizada por Rayos X , Humanos , Algoritmos , Aprendizaje Profundo , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Cabeza/diagnóstico por imagen
11.
J Immunol ; 207(12): 3016-3027, 2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-34772697

RESUMEN

Aicardi-Goutières syndrome (AGS) is a congenital inflammatory disorder accompanied by overactivated type I IFN signaling and encephalopathy with leukodystrophy and intracranial calcification. To date, none of the mouse models carrying an AGS-causative mutation has mimicked such brain pathology. Here, we established a mutant mouse model carrying a K948N point mutation, corresponding to an AGS-causative K999N mutation, located in a deaminase domain of the Adar1 gene that encodes an RNA editing enzyme. Adar1K948N/K948N mice displayed postnatal growth retardation. Hyperplasia of splenic white pulps with germinal centers and hepatic focal inflammation were observed from 2 mo of age. Inflammation developed in the lungs and heart with lymphocyte infiltration in an age-dependent manner. Furthermore, white matter abnormalities with astrocytosis and microgliosis were detected at 1 y of age. The increased expression of IFN-stimulated genes was detected in multiple organs, including the brain, from birth. In addition, single-nucleus RNA sequencing revealed that this elevated expression of IFN-stimulated genes was commonly observed in all neuronal subtypes, including neurons, oligodendrocytes, and astrocytes. We further showed that a K948N point mutation reduced the RNA editing activity of ADAR1 in vivo. The pathological abnormalities found in Adar1K948N/K948N mice were ameliorated by either the concurrent deletion of MDA5, a cytosolic sensor of unedited transcripts, or the sole expression of active ADAR1 p150, an isoform of ADAR1. Collectively, such data suggest that although the degree is mild, Adar1K948N/K948N mice mimic multiple AGS phenotypes, including encephalopathy, which is caused by reduced RNA editing activity of the ADAR1 p150 isoform.


Asunto(s)
Adenosina Desaminasa , Encefalopatías , Adenosina Desaminasa/genética , Adenosina Desaminasa/metabolismo , Animales , Enfermedades Autoinmunes del Sistema Nervioso , Inflamación/genética , Inflamación/metabolismo , Ratones , Mutación , Malformaciones del Sistema Nervioso , Mutación Puntual , Isoformas de Proteínas/genética , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo
12.
Macromol Rapid Commun ; 44(21): e2300323, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37668077

RESUMEN

The development of peptidomimetics to modulate the conformational profile of peptides has been extensively studied in the fields of biological and medicinal chemistry. However, large-scale synthesis of peptidomimetics with both an ordered sequence and a controlled secondary structure is highly challenging. In this paper, the framework of peptidomimetics has been designed to be alternating an achiral α,α-disubstituted α-amino acid unit and a chiral α-methylphenylalanine unit. The polymers are synthesized via invented Ugi reaction-based polycondensation technique. The chiral higher-order structures of the alternating peptides are evaluated mainly through circular dichroism (CD) spectroscopy. The UV-Vis and CD spectra of the polymers in three solvents are systematically measured at various temperatures. The anisotropic factors of CD (gCD ) values are calculated to know the chiroptical response. The results indicate the characteristic conformational behaviors. In a polar solvent, the hydrogen bonds between the N-H group of MePhe unit and the C=O of α,α-diphenylglycine unit outweigh the intraresidue hydrogen bonds in α,α-diphenylglycine unit, leading to the formation of a prevailing preferred-handed 310 -helical conformation. On the other hand, in a less polar solvent, the intrachain hydrogen bonds switch to intraresidue hydrogen bonds in α,α-diphenylglycine unit, which make the polymer adopting a prevailing extended planar C5 -conformation.


Asunto(s)
Peptidomiméticos , Péptidos/química , Aminoácidos/química , Estructura Secundaria de Proteína , Solventes/química , Polímeros , Dicroismo Circular
13.
Nature ; 543(7643): 131-135, 2017 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-28219079

RESUMEN

Photosystem II (PSII) is a huge membrane-protein complex consisting of 20 different subunits with a total molecular mass of 350 kDa for a monomer. It catalyses light-driven water oxidation at its catalytic centre, the oxygen-evolving complex (OEC). The structure of PSII has been analysed at 1.9 Å resolution by synchrotron radiation X-rays, which revealed that the OEC is a Mn4CaO5 cluster organized in an asymmetric, 'distorted-chair' form. This structure was further analysed with femtosecond X-ray free electron lasers (XFEL), providing the 'radiation damage-free' structure. The mechanism of O=O bond formation, however, remains obscure owing to the lack of intermediate-state structures. Here we describe the structural changes in PSII induced by two-flash illumination at room temperature at a resolution of 2.35 Å using time-resolved serial femtosecond crystallography with an XFEL provided by the SPring-8 ångström compact free-electron laser. An isomorphous difference Fourier map between the two-flash and dark-adapted states revealed two areas of apparent changes: around the QB/non-haem iron and the Mn4CaO5 cluster. The changes around the QB/non-haem iron region reflected the electron and proton transfers induced by the two-flash illumination. In the region around the OEC, a water molecule located 3.5 Å from the Mn4CaO5 cluster disappeared from the map upon two-flash illumination. This reduced the distance between another water molecule and the oxygen atom O4, suggesting that proton transfer also occurred. Importantly, the two-flash-minus-dark isomorphous difference Fourier map showed an apparent positive peak around O5, a unique µ4-oxo-bridge located in the quasi-centre of Mn1 and Mn4 (refs 4,5). This suggests the insertion of a new oxygen atom (O6) close to O5, providing an O=O distance of 1.5 Å between these two oxygen atoms. This provides a mechanism for the O=O bond formation consistent with that proposed previously.


Asunto(s)
Cristalografía/métodos , Electrones , Rayos Láser , Luz , Oxígeno/química , Oxígeno/efectos de la radiación , Complejo de Proteína del Fotosistema II/química , Complejo de Proteína del Fotosistema II/efectos de la radiación , Biocatálisis/efectos de la radiación , Cianobacterias/química , Transporte de Electrón/efectos de la radiación , Análisis de Fourier , Manganeso/química , Manganeso/metabolismo , Modelos Moleculares , Proteínas de Hierro no Heme/química , Proteínas de Hierro no Heme/metabolismo , Proteínas de Hierro no Heme/efectos de la radiación , Oxígeno/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Protones , Temperatura , Factores de Tiempo , Agua/química , Agua/metabolismo
14.
Support Care Cancer ; 31(2): 123, 2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36653680

RESUMEN

PURPOSE: Previous research suggests that the preoperative rehabilitation of colorectal cancer patients can reduce postoperative ileus. However, the evidence is insufficient and further research is warranted. This study aimed to investigate whether short-term preoperative rehabilitation, both on an outpatient and inpatient basis, can reduce the incidence of postoperative ileus after colorectal cancer surgery. METHODS: This was a retrospective cohort study that drew on data from multicenter electronic medical records. Patients with stage 1-3 colorectal cancer who underwent surgery and postoperative rehabilitation were included. The incidence of postoperative ileus was compared between patients who received short-term preoperative rehabilitation and those who did not. Propensity score adjustment using inverse probability weighting and subgroup analysis by type of surgery was performed. RESULTS: Four thousand seventy-six eligible patients (43.4% female; mean age 75.1 ± 10.9 years) were included; 1914 (47.0%) received short-term preoperative rehabilitation. The preoperative rehabilitation group had a significantly lower incidence of postoperative ileus than the no preoperative rehabilitation group (pre-adjustment: 5.5% vs. 9.9%, p < 0.001; post-adjustment: 5.2% vs. 9.0%, p < 0.001). Therefore, preoperative rehabilitation was significantly associated with a lower incidence of postoperative ileus (OR: 0.554, 95% CI: 0.415-0.739, p < 0.001). In an adjusted analysis of surgery type subgroups, the incidence of postoperative ileus was significantly lower in the preoperative rehabilitation group for all types of surgery. CONCLUSION: Our study showed that short-term preoperative rehabilitation for patients with stage 1-3 colorectal cancer, both with inpatients and outpatients, significantly reduces the incidence of postoperative ileus.


Asunto(s)
Neoplasias Colorrectales , Procedimientos Quirúrgicos del Sistema Digestivo , Ileus , Humanos , Femenino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Masculino , Estudios Retrospectivos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Ileus/epidemiología , Ileus/etiología , Ileus/prevención & control , Neoplasias Colorrectales/cirugía , Neoplasias Colorrectales/complicaciones
15.
Int J Mol Sci ; 24(5)2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36901788

RESUMEN

Curli fimbriae are amyloids-found in bacteria (Escherichia coli)-that are involved in solid-surface adhesion and bacterial aggregation during biofilm formation. The curli protein CsgA is coded by a csgBAC operon gene, and the transcription factor CsgD is essential to induce its curli protein expression. However, the complete mechanism underlying curli fimbriae formation requires elucidation. Herein, we noted that curli fimbriae formation was inhibited by yccT-i.e., a gene that encodes a periplasmic protein of unknown function regulated by CsgD. Furthermore, curli fimbriae formation was strongly repressed by CsgD overexpression caused by a multicopy plasmid in BW25113-the non-cellulose-producing strain. YccT deficiency prevented these CsgD effects. YccT overexpression led to intracellular YccT accumulation and reduced CsgA expression. These effects were addressed by deleting the N-terminal signal peptide of YccT. Localization, gene expression, and phenotypic analyses revealed that YccT-dependent inhibition of curli fimbriae formation and curli protein expression was mediated by the two-component regulatory system EnvZ/OmpR. Purified YccT inhibited CsgA polymerization; however, no intracytoplasmic interaction between YccT and CsgA was detected. Thus, YccT-renamed CsgI (curli synthesis inhibitor)-is a novel inhibitor of curli fimbriae formation and has a dual role as an OmpR phosphorylation modulator and CsgA polymerization inhibitor.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas Bacterianas/metabolismo , Biopelículas , Adhesión Bacteriana/genética , Polimerizacion , Transactivadores/metabolismo , Expresión Génica , Regulación Bacteriana de la Expresión Génica
16.
J Anesth ; 37(3): 474-481, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37120585

RESUMEN

Chlorhexidine is a common cause of perioperative anaphylaxis, and global regulatory authorities have issued warnings about anaphylaxis due to chlorhexidine-containing central venous catheters (CVC) and its mucosal absorption. We present a case of life-threatening anaphylaxis after CVC insertion caused by chlorhexidine used for skin preparation. The onset of anaphylaxis was rapid and very severe, resulting in pulseless electrical activity. The patient was successfully resuscitated by emergency veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Our case suggests that even skin preparation before chlorhexidine-free CVC insertion can cause life-threatening anaphylaxis. We reviewed the literature on chlorhexidine anaphylaxis cases and categorized all potential routes of chlorhexidine exposure to assess the risk following skin preparation. Our results showed that skin preparation before CVC insertion was the third most common cause of chlorhexidine anaphylaxis after transurethral exposure and chlorhexidine-containing CVCs. However, skin preparation with chlorhexidine before CVC insertion was sometimes overlooked as a cause of chlorhexidine anaphylaxis, and its risk might be underestimated. Further, no previous reports have described life-threatening anaphylaxis solely due to chlorhexidine skin preparation before CVC insertion. CVC insertion might cause the chlorhexidine used for skin preparation to reach the vascular system and should be recognized as a potential cause of life-threatening chlorhexidine anaphylaxis.


Asunto(s)
Anafilaxia , Infecciones Relacionadas con Catéteres , Cateterismo Venoso Central , Catéteres Venosos Centrales , Humanos , Clorhexidina/efectos adversos , Catéteres Venosos Centrales/efectos adversos , Anafilaxia/inducido químicamente , Cateterismo Venoso Central/efectos adversos
17.
RNA ; 26(4): 454-469, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31941663

RESUMEN

Adenosine-to-inosine RNA editing is an essential post-transcriptional modification catalyzed by adenosine deaminase acting on RNA (ADAR)1 and ADAR2 in mammals. For numerous sites in coding sequences (CDS) and microRNAs, editing is highly conserved and has significant biological consequences, for example, by altering amino acid residues and target recognition. However, no comprehensive and quantitative studies have been undertaken to determine how specific ADARs contribute to conserved sites in vivo. Here, we amplified each RNA region with editing site(s) separately and combined these for deep sequencing. Then, we compared the editing ratios of all sites that were conserved in CDS and microRNAs in the cerebral cortex and spleen of wild-type mice, Adar1E861A/E861AIfih-/- mice expressing inactive ADAR1 (Adar1 KI) and Adar2-/-Gria2R/R (Adar2 KO) mice. We found that most of the sites showed a preference for one ADAR. In contrast, some sites, such as miR-3099-3p, showed no ADAR preference. In addition, we found that the editing ratio for several sites, such as DACT3 R/G, was up-regulated in either Adar mutant mouse strain, whereas a coordinated interplay between ADAR1 and ADAR2 was required for the efficient editing of specific sites, such as the 5-HT2CR B site. We further created double mutant Adar1 KI Adar2 KO mice and observed viable and fertile animals with the complete absence of editing, demonstrating that ADAR1 and ADAR2 are the sole enzymes responsible for all editing sites in vivo. Collectively, these findings indicate that editing is regulated in a site-specific manner by the different interplay between ADAR1 and ADAR2.


Asunto(s)
Adenosina Desaminasa/metabolismo , MicroARNs/metabolismo , Edición de ARN , Proteínas de Unión al ARN/metabolismo , Adenosina Desaminasa/genética , Animales , Femenino , Masculino , Ratones , MicroARNs/genética , Mutación , Motivos de Nucleótidos , Proteínas de Unión al ARN/genética
18.
Photosynth Res ; 152(2): 135-151, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34985636

RESUMEN

Photosystem II (PSII) performs oxidation of water and reduction of plastoquinone through light-induced electron transfer. Electron transfer reactions at individual redox cofactors are controlled by their redox potentials, and the forward and backward electron flows in PSII are regulated by tuning them. It is, thus, crucial to accurately estimate the redox potentials of the cofactors and their shifts by environmental changes to understand the regulatory mechanisms in PSII. Fourier-transform infrared (FTIR) spectroelectrochemistry combined with a light-induced difference technique is a powerful method to investigate the mechanisms of the redox reactions in PSII. In this review, we introduce the methodology and the application of this method in the studies of the iron-quinone complex, which consists of two plastoquinone molecules, QA and QB, and the non-heme iron, on the electron-acceptor side of PSII. It is shown that FTIR spectroelectrochemistry is a useful method not only for estimating the redox potentials but also for detecting the reactions of nearby amino-acid residues coupled with the redox reactions.


Asunto(s)
Complejo de Proteína del Fotosistema II , Plastoquinona , Transporte de Electrón , Electrones , Hierro , Oxidación-Reducción , Quinonas , Espectroscopía Infrarroja por Transformada de Fourier
19.
Aging Male ; 25(1): 249-254, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36190764

RESUMEN

Aim: This study investigated the relationship between erectile dysfunction (ED) and adiponectin levels in hypogonadal men.Methods: In this study, 218 patients with hypogonadism (mean age: 65.1 ± 8.3 years) were enrolled. All patients underwent physical examinations, with measurement of body mass index, body fat ratio, and waist circumference. The erectile function was assessed using the sexual health inventory for men (SHIM) scoring system. Blood biochemical profiles such as free testosterone, fasting blood glucose, and lipid profile including adiponectin levels were measured. All patients were divided into two groups based on their SHIM score: normal to moderate ED (SHIM score ≥ 12) and severe ED (SHIM score < 12), and the factors associated with severe ED were determined. Patients with severe ED were divided into two groups based on adiponectin levels (cutoff value of 7.0 µg/mL), and their basic characteristics were compared between these two groups.Results: The severe ED group was older and had higher adiponectin levels. In patients with severe ED, various metabolic parameters were significantly worse in the low adiponectin groups than in the non-low adiponectin group.Conclusions: The risk of developing cardiovascular diseases is extremely high in hypogonadal men with severe ED who had lower serum adiponectin levels.


Asunto(s)
Disfunción Eréctil , Hipogonadismo , Adiponectina , Anciano , Glucemia/metabolismo , Humanos , Hipogonadismo/complicaciones , Lípidos , Masculino , Testosterona
20.
J Immunol ; 204(8): 2156-2168, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-32169840

RESUMEN

ADAR1 is an RNA-editing enzyme that is abundant in the thymus. We have previously reported that ADAR1 is required for establishing central tolerance during the late stage of thymocyte development by preventing MDA5 sensing of endogenous dsRNA as nonself. However, the role of ADAR1 during the early developmental stage remains unknown. In this study, we demonstrate that early thymocyte-specific deletion of ADAR1 in mice caused severe thymic atrophy with excessive apoptosis and impaired transition to a late stage of development accompanied by the loss of TCR expression. Concurrent MDA5 deletion ameliorated apoptosis but did not restore impaired transition and TCR expression. In addition, forced TCR expression was insufficient to restore the transition. However, simultaneous TCR expression and MDA5 deletion efficiently ameliorated the impaired transition of ADAR1-deficient thymocytes to the late stage. These findings indicate that RNA-editing-dependent and -independent functions of ADAR1 synergistically regulate early thymocyte development.


Asunto(s)
Adenosina Desaminasa/metabolismo , Helicasa Inducida por Interferón IFIH1/metabolismo , Timocitos/inmunología , Adenosina Desaminasa/deficiencia , Adenosina Desaminasa/genética , Animales , Apoptosis/genética , Apoptosis/inmunología , Helicasa Inducida por Interferón IFIH1/deficiencia , Helicasa Inducida por Interferón IFIH1/genética , Ratones , Ratones Noqueados , Ratones Mutantes , Edición de ARN/genética , Edición de ARN/inmunología , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/inmunología
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