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1.
Nucleic Acids Res ; 52(1): 141-153, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-37985205

RESUMEN

Genetic modification of specific genes is emerging as a useful tool to enhance the functions of antitumor T cells in adoptive immunotherapy. Current advances in CRISPR/Cas9 technology enable gene knockout during in vitro preparation of infused T-cell products through transient transfection of a Cas9-guide RNA (gRNA) ribonucleoprotein complex. However, selecting optimal gRNAs remains a major challenge for efficient gene ablation. Although multiple in silico tools to predict the targeting efficiency have been developed, their performance has not been validated in cultured human T cells. Here, we explored a strategy to select optimal gRNAs using our pooled data on CRISPR/Cas9-mediated gene knockout in human T cells. The currently available prediction tools alone were insufficient to accurately predict the indel percentage in T cells. We used data on the epigenetic profiles of cultured T cells obtained from transposase-accessible chromatin with high-throughput sequencing (ATAC-seq). Combining the epigenetic information with sequence-based prediction tools significantly improved the gene-editing efficiency. We further demonstrate that epigenetically closed regions can be targeted by designing two gRNAs in adjacent regions. Finally, we demonstrate that the gene-editing efficiency of unstimulated T cells can be enhanced through pretreatment with IL-7. These findings enable more efficient gene editing in human T cells.


Asunto(s)
Sistemas CRISPR-Cas , Técnicas de Inactivación de Genes , Linfocitos T , Humanos , Sistemas CRISPR-Cas/genética , Edición Génica , Linfocitos T/metabolismo
2.
Int Immunol ; 36(7): 353-364, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38517027

RESUMEN

The efficient generation of chimeric antigen receptor (CAR) T cells is highly influenced by the quality of apheresed T cells. Healthy donor-derived T cells usually proliferate better than patients-derived T cells and are precious resources to generate off-the-shelf CAR-T cells. However, relatively little is known about the determinants that affect the efficient generation of CAR-T cells from healthy donor-derived peripheral blood mononuclear cells (PBMCs) compared with those from the patients' own PBMCs. We here examined the efficiency of CAR-T cell generation from multiple healthy donor samples and analyzed its association with the phenotypic features of the starting peripheral blood T cells. We found that CD62L expression levels within CD8+ T cells were significantly correlated with CAR-T cell expansion. Moreover, high CD62L expression within naïve T cells was associated with the efficient expansion of T cells with a stem cell-like memory phenotype, an indicator of high-quality infusion products. Intriguingly, genetic disruption of CD62L significantly impaired CAR-T cell proliferation and cytokine production upon antigen stimulation. Conversely, ectopic expression of a shedding-resistant CD62L mutant augmented CAR-T cell effector functions compared to unmodified CAR-T cells, resulting in improved antitumor activity in vivo. Collectively, we identified the surface expression of CD62L as a concise indicator of potent T-cell proliferation. CD62L expression is also associated with the functional properties of CAR-T cells. These findings are potentially applicable to selecting optimal donors to massively generate CAR-T cell products.


Asunto(s)
Inmunoterapia Adoptiva , Selectina L , Receptores Quiméricos de Antígenos , Selectina L/metabolismo , Selectina L/inmunología , Humanos , Receptores Quiméricos de Antígenos/inmunología , Receptores Quiméricos de Antígenos/genética , Receptores Quiméricos de Antígenos/metabolismo , Animales , Ratones , Inmunoterapia Adoptiva/métodos , Proliferación Celular
3.
Biochem Biophys Res Commun ; 728: 150345, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38971001

RESUMEN

The transfer of nitrogen fixation (nif) genes from diazotrophs to non-diazotrophic hosts is of increasing interest for engineering biological nitrogen fixation. A recombinant Escherichia coli strain expressing Azotobacter vinelandii 18 nif genes (nifHDKBUSVQENXYWZMF, nifiscA, and nafU) were previously constructed and showed nitrogenase activity. In the present study, we constructed several E. coli strain derivatives in which all or some of the 18 nif genes were additionally integrated into the fliK locus of the chromosome in various combinations. E. coli derivatives with the chromosomal integration of nifiscA, nifU, and nifS, which are involved in the biosynthesis of the [4Fe-4S] cluster of dinitrogenase reductase, exhibited enhanced nitrogenase activity. We also revealed that overexpression of E. coli fldA and ydbK, which encode flavodoxin and flavodoxin-reducing enzyme, respectively, enhanced nitrogenase activity, likely by facilitating electron transfer to dinitrogenase reductase. The additional expression of nifM, putatively involved in maturation of dinitrogenase reductase, further enhanced nitrogenase activity and the amount of soluble NifH. By combining these factors, we successfully improved nitrogenase activity 10-fold.

4.
Opt Lett ; 49(9): 2321-2324, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38691709

RESUMEN

In this Letter, we propose a crackless high-aspect-ratio processing method based on a temporally shaped ultrafast laser. The laser pulse is temporally split into two sub pulses: one with smaller energy is used to excite electrons but without ablation so that the applied pressure to the sample is weak, and the other one is used to heat the electrons and achieve material removal after it is temporally stretched by a chirped volume Bragg grating (CVBG). Compared with the conventional ultrafast laser processing, the crack generation is almost suppressed by using this proposed method. The hole depth increases more than 3.3 times, and the aspect ratio is improved at least 2.2 times. Moreover, processing dynamics and parameter dependence are further experimentally studied. It shows that the processing highly depends on the density of electrons excited by the first pulse (P1) and the energy of the second pulse (P2). This novel, to the best of our knowledge, method provides a new route for the precise processing of wide-bandgap materials.

5.
J Nat Prod ; 87(5): 1358-1367, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38656153

RESUMEN

cis-12-oxo-Phytodieneoic acid-α-monoglyceride (1) was isolated from Arabidopsis thaliana. The chemical structure of 1 was elucidated based on exhaustive 1D and 2D NMR spectroscopic measurements and supported by FDMS and HRFDMS data. The absolute configuration of the cis-OPDA moiety in 1 was determined by comparison of 1H NMR spectra and ECD measurements. With respect to the absolute configuration of the ß-position of the glycerol backbone, the 2:3 ratio of (S) to (R) was determined by making ester-bonded derivatives with (R)-(+)-α-methoxy-α-trifluoromethylphenylacetyl chloride and comparing 1H NMR spectra. Wounding stress did not increase endogenous levels of 1, and it was revealed 1 had an inhibitory effect of A. thaliana post germination growth. Notably, the endogenous amount of 1 was higher than the amounts of (+)-7-iso-jasmonic acid and (+)-cis-OPDA in intact plants. 1 also showed antimicrobial activity against Gram-positive bacteria, but jasmonic acid did not. It was also found that α-linolenic acid-α-monoglyceride was converted into 1 in the A. thaliana plant, which implied α-linolenic acid-α-monoglyceride was a biosynthetic intermediate of 1.


Asunto(s)
Arabidopsis , Estructura Molecular , Monoglicéridos/farmacología , Monoglicéridos/química , Ciclopentanos/farmacología , Ciclopentanos/química , Oxilipinas/química , Oxilipinas/farmacología , Ácidos Grasos Insaturados/química , Ácidos Grasos Insaturados/farmacología , Ácidos Grasos Insaturados/aislamiento & purificación , Germinación/efectos de los fármacos
6.
Eur Spine J ; 33(2): 379-385, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38227214

RESUMEN

PURPOSE: This study aimed to investigate the impact of the severity of cervical ossification of the posterior longitudinal ligament (OPLL) on the incidence of arteriosclerosis in the carotid artery. METHODS: Patients with OPLL-induced cervical myelopathy were prospectively enrolled. The study involved analyzing patient characteristics, blood samples, computed tomography scans of the spine, and intima-media thickness (IMT) measurements of the common carotid artery. Patients were divided into two groups based on the size of the cervical OPLL to compare demographic data, comorbidities, and the presence of thickening of the carotid intima-media (max IMT ≥ 1.1 mm). RESULTS: The study included 96 patients (mean age: 63.5 years; mean body mass index: 26.9 kg/m2; 71.8% male; 35.4% with diabetes mellitus). The mean maximum anteroposterior (AP) diameter of the OPLL was 4.9 mm, with a mean occupancy ratio of 43%. The mean maximum IMT was 1.23 mm. Arteriosclerosis of the carotid artery was diagnosed in 62.5% of the patients. On comparing the two groups based on OPLL size, the group with larger OPLL (≥ 5 mm) had a higher BMI and a greater prevalence of carotid intima-media thickening. This significant difference in the prevalence of carotid intima-media thickening persisted even after adjusting for patient backgrounds using propensity score matching. CONCLUSIONS: Patients with a larger cervical OPLL showed a higher frequency of intima-media thickening in the carotid artery.


Asunto(s)
Arteriosclerosis , Osificación del Ligamento Longitudinal Posterior , Humanos , Masculino , Persona de Mediana Edad , Femenino , Ligamentos Longitudinales , Grosor Intima-Media Carotídeo , Incidencia , Osteogénesis , Arteria Carótida Común , Osificación del Ligamento Longitudinal Posterior/diagnóstico por imagen , Osificación del Ligamento Longitudinal Posterior/epidemiología
7.
Int J Urol ; 31(6): 678-684, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38402449

RESUMEN

OBJECTIVE: In December 2021, enfortumab vedotin (EV), an antibody-drug conjugate directed against nectin-4, was approved in Japan as a new treatment after platinum-containing chemotherapy and PD-1/PD-L1 inhibitors. This study evaluated, using real-world data, the efficacy and safety of EV therapy in patients with metastatic urothelial carcinoma (mUC). MATERIALS AND METHODS: Fifty-five patients with mUC who discontinued pembrolizumab therapy due to disease progression between June 2018 and April 2023 at Yokohama City University Hospital were evaluated retrospectively. Of the 55 patients, 25 received EV therapy (EV group) and 30 did not (non-EV group). All patients who underwent EV therapy were diagnosed with disease progression after the approval of EV in Japan. RESULTS: The median (range) follow-up period after pembrolizumab discontinuation was 6.3 (0.7-31.1) months. There were eight (32.0%) deaths due to cancer in the EV group and 27 (90.0%) in the non-EV group. The overall survival (OS) after pembrolizumab discontinuation was not reached in the EV group versus 2.6 months in the non-EV group (p < 0.001). A multivariate analysis revealed that EV therapy (EV vs. non-EV group; hazard ratio 0.26; 95% confidence interval 0.16-0.41; p < 0.001) was an independent prognostic factor for OS. CONCLUSION: EV prolonged OS in mUC following pembrolizumab therapy in real-world data.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Antineoplásicos Inmunológicos , Carcinoma de Células Transicionales , Humanos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Masculino , Femenino , Anciano , Estudios Retrospectivos , Persona de Mediana Edad , Carcinoma de Células Transicionales/tratamiento farmacológico , Carcinoma de Células Transicionales/mortalidad , Carcinoma de Células Transicionales/secundario , Anciano de 80 o más Años , Antineoplásicos Inmunológicos/uso terapéutico , Antineoplásicos Inmunológicos/efectos adversos , Japón/epidemiología , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/mortalidad , Neoplasias de la Vejiga Urinaria/patología , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales/efectos adversos , Neoplasias Urológicas/tratamiento farmacológico , Neoplasias Urológicas/mortalidad , Neoplasias Urológicas/patología , Progresión de la Enfermedad , Tasa de Supervivencia , Inmunoconjugados/uso terapéutico , Inmunoconjugados/efectos adversos
8.
Blood ; 138(24): 2555-2569, 2021 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-34587247

RESUMEN

Neutrophils play an essential role in innate immune responses to bacterial and fungal infections, and loss of neutrophil function can increase the risk of acquiring lethal infections in clinical settings. Here, we show that engineered neutrophil-primed progenitors derived from human induced pluripotent stem cells can produce functional neutrophil-like cells at a clinically applicable scale that can act rapidly in vivo against lethal bacterial infections. Using 5 different mouse models, we systematically demonstrated that these neutrophil-like cells migrate to sites of inflammation and infection and increase survival against bacterial infection. In addition, we found that these human neutrophil-like cells can recruit murine immune cells. This system potentially provides a straight-forward solution for patients with neutrophil deficiency: an off-the-shelf neutrophil transfusion. This platform should facilitate the administration of human neutrophils for a broad spectrum of physiological and pathological conditions.


Asunto(s)
Infecciones Bacterianas/terapia , Células Madre Pluripotentes Inducidas/citología , Neutrófilos/trasplante , Animales , Infecciones Bacterianas/inmunología , Técnicas de Cultivo de Célula , Proliferación Celular , Células Cultivadas , Modelos Animales de Enfermedad , Humanos , Inmunidad Innata , Células Madre Pluripotentes Inducidas/inmunología , Inflamación/inmunología , Inflamación/terapia , Ratones Endogámicos BALB C , Neutrófilos/citología , Neutrófilos/inmunología
9.
Opt Express ; 31(23): 38191-38204, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-38017931

RESUMEN

Femtosecond laser processing has been widely applied in glass processing owing to its ability to fabricate microscale components. To improve processing efficiency, a transient and selective laser (TSL) processing technique was previously developed, in which electron excitation was induced inside a transparent medium by a single pulse of femtosecond (fs) laser, and a single pulse of microsecond (µs) laser can be selectively absorbed in this excited region to heat and remove the material. However, because of its high speed removal process, the unclear mechanism and inefficient evaluation of its processing performance limit its further application. This study analyzes the transient spatiotemporal evolution of the induced plasma and the related material removal mechanism of the TSL processing using a side high-speed monitoring method. To achieve a rapid performance evaluation, a quantitative analysis of the optical plasma signals (on a microsecond timescale) generated in TSL processing was performed by employing a developed coaxial high-speed monitoring method using a photodetector. The variations in the shapes, intensity distribution, and dimensions of the plasma were quantitatively investigated. In addition, the relation between the plasma signal and drilling performance under different laser parameters, including hole depth, hole types, and cracks, was explored and quantitatively analyzed. The revealed mechanism is expected to contribute to the broadening of the application of TSL processing in microfabrication. Furthermore, the developed high-speed and precision monitoring technology can be utilized for high-speed evaluation and precision control of machining quality in real time during ultrahigh-speed laser machining, without time-consuming camera observations.

10.
Crit Care ; 27(1): 442, 2023 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-37968720

RESUMEN

BACKGROUND: Extracorporeal cardiopulmonary resuscitation (ECPR) has been proposed as a rescue therapy for patients with refractory cardiac arrest. This study aimed to evaluate the association between ECPR and clinical outcomes among patients with out-of-hospital cardiac arrest (OHCA) using risk-set matching with a time-dependent propensity score. METHODS: This was a secondary analysis of the JAAM-OHCA registry data, a nationwide multicenter prospective study of patients with OHCA, from June 2014 and December 2019, that included adults (≥ 18 years) with OHCA. Initial cardiac rhythm was classified as shockable and non-shockable. Patients who received ECPR were sequentially matched with the control, within the same time (minutes) based on time-dependent propensity scores calculated from potential confounders. The odds ratios with 95% confidence intervals (CI) for 30-day survival and 30-day favorable neurological outcomes were estimated for ECPR cases using a conditional logistic model. RESULTS: Of 57,754 patients in the JAAM-OHCA registry, we selected 1826 patients with an initial shockable rhythm (treated with ECPR, n = 913 and control, n = 913) and a cohort of 740 patients with an initial non-shockable rhythm (treated with ECPR, n = 370 and control, n = 370). In these matched cohorts, the odds ratio for 30-day survival in the ECPR group was 1.76 [95%CI 1.38-2.25] for shockable rhythm and 5.37 [95%CI 2.53-11.43] for non-shockable rhythm, compared to controls. For favorable neurological outcomes, the odds ratio in the ECPR group was 1.11 [95%CI 0.82-1.49] for shockable rhythm and 4.25 [95%CI 1.43-12.63] for non-shockable rhythm, compared to controls. CONCLUSION: ECPR was associated with increased 30-day survival in patients with OHCA with initial shockable and even non-shockable rhythms. Further research is warranted to investigate the reproducibility of the results and who is the best candidate for ECPR.


Asunto(s)
Reanimación Cardiopulmonar , Paro Cardíaco Extrahospitalario , Adulto , Humanos , Paro Cardíaco Extrahospitalario/terapia , Puntaje de Propensión , Estudios Prospectivos , Japón/epidemiología , Reproducibilidad de los Resultados , Reanimación Cardiopulmonar/métodos , Hospitales , Sistema de Registros , Estudios Retrospectivos
11.
J Pediatr Hematol Oncol ; 45(1): 21-24, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-35972935

RESUMEN

Although infection is common in patients with cancer, the distribution of causative agents and the proportion of resistant bacteria in patients with urinary tract infection remain unknown. The aim of this study was to describe the incidence, the causative agents, and the proportion of antimicrobial resistance in bacteria cultured from urine of hospitalized children with cancer. A single-center retrospective chart review of patients with cancer admitted between 2012 and 2020 was performed to identify patients with positive urine culture. Overall, 61 (0.9%) of 7107 patients were identified to have positive urine cultures. Among them, 25 patients (41%) had symptomatic bacteriuria. The most common pathogenic bacterium among all patients was Escherichia coli ( E. coli ) (n=15, 25%), followed by Enterococcus sp. (n=14, 23%), Klebsiella sp. (n=12, 20%), and Pseudomonas aeruginosa ( P. aeruginosa ) (n=12, 20%). Extended spectrum ß-lactamases-producing E. coli and Extended spectrum ß-lactamases-producing Klebsiella pneumoniae were detected in 1 patient (2%) and 4 patients (7%), respectively. No multidrug-resistant P. aeruginosa and vancomycin-resistant Enterococcus were detected. The incidence of bacteriuria was found to be low in children with cancer. The distribution of causative agents of bacteriuria in children with solid tumors and hematologic diseases may be different from that in previously healthy children.


Asunto(s)
Bacteriuria , Neoplasias , Infecciones Urinarias , Humanos , Niño , Bacteriuria/epidemiología , Bacteriuria/tratamiento farmacológico , Bacteriuria/microbiología , Escherichia coli , Incidencia , Estudios Retrospectivos , Infecciones Urinarias/etiología , Bacterias , beta-Lactamasas , Neoplasias/complicaciones , Neoplasias/epidemiología , Neoplasias/tratamiento farmacológico , Antibacterianos/uso terapéutico , Pruebas de Sensibilidad Microbiana
12.
Int J Urol ; 30(12): 1096-1102, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37592739

RESUMEN

OBJECTIVES: To investigate the predictive factors for pentafecta achievement of robot-assisted partial nephrectomy (RAPN) for intermediate highly complex renal tumors (RENAL score ≥ 7). METHODS: We retrospectively analyzed the data of 247 patients with renal tumors with a RENAL score ≥ 7 who underwent RAPN. Baseline characteristics and perioperative outcomes were compared between the pentafecta achieved group and the unachieved group. A multivariable logistic regression model was used to identify the predictive factors for pentafecta achievement for cT1 renal tumors with a RENAL score ≥ 7. RESULTS: Of the 247 patients, 75 (30.3%) patients were in the achieved group and 172 (69.7%) patients were in the unachieved group. The median warm ischemia time and total operation time were 18 min versus 23 min (p < 0.001) and 179 min versus 201 min (p < 0.001) in the achieved and unachieved groups, respectively. In the unachieved group, six patients (3.4%) had major perioperative complications (Clavien-Dindo classification system ≥3). The median preservation rates of estimated GFR at the 1-year postoperative period were 96.5% versus 83.0% (p < 0.001) in the achieved and unachieved groups. Multivariable logistic regression models revealed that age and tumor size were independent predictive factors for pentafecta achievement for cT1 renal tumors with a RENAL score ≥ 7. There were no significant differences in cancer-free survival between the two groups (p = 0.456). CONCLUSION: Age and tumor size were independent predictive factors for pentafecta achievement, although there was no difference in oncological outcomes between the pentafecta achieved group and the unachieved group in RAPN for cT1 renal tumors with a RENAL score ≥ 7.


Asunto(s)
Neoplasias Renales , Procedimientos Quirúrgicos Robotizados , Robótica , Humanos , Estudios Retrospectivos , Resultado del Tratamiento , Neoplasias Renales/cirugía , Neoplasias Renales/patología , Nefrectomía/efectos adversos , Procedimientos Quirúrgicos Robotizados/efectos adversos
13.
Cancer Sci ; 113(11): 3664-3671, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36000807

RESUMEN

Recent advancements in cancer immunotherapy, such as chimeric antigen receptor (CAR)-engineered T cell therapy and immune checkpoint therapy, have significantly improved the clinical outcomes of patients with several types of cancer. To broaden its applicability further and induce durable therapeutic efficacy, it is imperative to understand how antitumor T cells elicit cytotoxic functions, survive as memory T cells, or are impaired in their effector functions (exhausted) at the molecular level. T cell properties are regulated by their gene expression profiles, which are further controlled by epigenetic architectures, such as DNA methylation and histone modifications. Multiple studies have elucidated specific epigenetic genes associated with T-cell phenotypic changes. Conversely, exogenous modification of these key epigenetic factors can significantly alter T cell functions by extensively altering the transcription network, which can be applied in cancer immunotherapy by improving T cell persistence or augmenting effector functions. As CAR-T cell therapy involves a genetic engineering step during the preparation of the infusion products, it would be a feasible strategy to additionally modulate specific epigenetic genes in CAR-T cells to improve their quality. Here, we review recent studies investigating how individual epigenetic factors play a crucial role in T-cell biology. We further discuss future directions to integrate these findings for optimal cancer immunotherapy.


Asunto(s)
Neoplasias , Receptores Quiméricos de Antígenos , Humanos , Inmunoterapia Adoptiva/efectos adversos , Neoplasias/genética , Neoplasias/terapia , Tratamiento Basado en Trasplante de Células y Tejidos , Epigénesis Genética , Receptores de Antígenos de Linfocitos T
14.
Opt Express ; 30(4): 4954-4964, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35209467

RESUMEN

The evolution mechanism of femtosecond laser-induced filaments has been widely investigated owing to its application prospects in microprocessing. However, the material dependence of the excitation, stability, and decay of filaments is not well understood despite the importance of their precise utilization. In this study, the spatiotemporal evolution of filaments induced by a single femtosecond laser pulse in sapphire and silica glass was investigated using time-resolved pump-probe shadowgraphy on femtosecond and picosecond timescales. The results revealed that the evolution was significantly different in the two typically transparent dielectrics in terms of the electronic plasma dynamics and filament lifetimes. This difference can be attributed to the self-trapped excitons (STEs) in silica glass. Furthermore, the filament dependence on pump energy and focal position was experimentally analyzed. Divergent filaments were observed when the focal position was near the surface because of the effect of the excited plasma on beam propagation. Moreover, the evolution of filament length in the two materials was discussed. This study contributes to the applications of filaments in precise processing.

15.
Opt Express ; 30(21): 37394-37406, 2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-36258328

RESUMEN

Femtosecond lasers have been applied to machining of zirconia (ZrO2) ceramics because of their ultrashort pulse duration and high peak power. However, an unclear understanding of the ultrafast laser-material interaction mechanisms limits the achievement of precision processing. In this study, a pump-probe imaging method comprising a focusing probe beam integrated with a high-speed camera was developed to directly observe and quantitatively evaluate the multi-timescale transient processing phenomena, including electron excitation, shockwave propagation, plasma evolution, and hole formation, occurring on the picosecond to second timescales, inside a ZrO2 sample. The variation mechanism in the shapes, lifetimes, and dimensions of these phenomena and their impacts on the drilling performance under different laser parameters were explored. The clear imaging and investigation of the above phenomena contribute to revealing the ultrafast laser-material interaction mechanisms and precision processing in the laser-drilling of zirconia ceramics.

16.
Opt Express ; 30(18): 32280-32291, 2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36242293

RESUMEN

Microgroove processing of glass is important in many fields, however, it is difficult to achieve the processing with a high speed. In this study, we developed a novel method for the high-speed microgroove processing of glass using two types of lasers, namely a femtosecond laser and a near-infrared continuous-wave (CW) laser. A single femtosecond laser pulse was initially focused on the surface of the material, enabling the area to absorb the CW laser, which is otherwise not absorbed by the glass. The CW laser was then scanned along the material surface, expanding the machined hole to form a groove. The resulting grooves, with a width of approximately 10 µm and depths of up to 350 µm, can be machined with a scanning speed of up to 200 mm/s, 25 times faster than conventional methods. This method exhibits the potential to improve the industrial application of fast laser microprocessing of glass.

17.
Appl Opt ; 61(2): 352-361, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35200869

RESUMEN

We have developed an active alignment of receiving beam (AARB) function for coaxial optics in wind sensing coherent Doppler lidar using feedback control based on the heterodyne-detected signal processing of backscattered light from the aerosols. The proposed method needs only the simple alignment components and contributes to the robustness for the coherent lidars with the high-power laser transmitter under the risky condition of misalignment, for example, in the airborne application. The concept, design, and evaluation results of the alignment precision are shown. The effect of the AARB is demonstrated for both cases of the hard target and soft target (i.e., wind sensing). To the best of our knowledge, this is the first demonstration of the AARB concept for the wind sensing coherent lidar.

18.
J Infect Chemother ; 28(6): 806-809, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35078720

RESUMEN

The widespread adoption of pneumococcal conjugate vaccines has reduced the incidence of Streptococcus pneumoniae infections, but has also led to the emergence of infections due to non-vaccine serotypes. A 15-month-old girl was referred to our hospital with suspected meningitis. S. pneumoniae was isolated from her cerebrospinal fluid. She was initially treated with a combination of cefotaxime and vancomycin, followed by ampicillin and vancomycin. After 7 days, the patient's condition improved and she was transferred to the general ward; however, her mother noted signs of hearing difficulties. On the 16th day of admission, we performed an auditory brainstem response test, which suggested severe bilateral hearing impairment. This was confirmed using an auditory steady-state response test after consulting with otolaryngologists. Magnetic resonance imaging revealed fibrosis of both cochleae with labyrinthitis. The patient underwent emergency cochlear implantation at a different hospital. The S. pneumoniae isolate was later identified to be serotype 10A with a PBP2x mutation, which is not covered by the conjugate vaccine and has reduced cephalosporin susceptibility. This case was characterized by highly rapid cochlear destruction, and an earlier otolaryngologist consultation may have provided a more well-organized surgery plan. Pediatricians are urged to promptly consult with otolaryngologists for patients with similar indications.


Asunto(s)
Meningitis Neumocócica , Infecciones Neumocócicas , Femenino , Humanos , Lactante , Meningitis Neumocócica/complicaciones , Meningitis Neumocócica/diagnóstico , Meningitis Neumocócica/tratamiento farmacológico , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas , Serogrupo , Serotipificación , Streptococcus pneumoniae/genética , Vacunas Conjugadas/uso terapéutico , Vancomicina/uso terapéutico
19.
J Theor Biol ; 509: 110493, 2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-32956668

RESUMEN

Chimeric simian and human immunodeficiency viruses (SHIVs) are appropriate animal models for the human immunodeficiency virus (HIV) because HIV has quite a narrow host range. Additionally, SHIVs that encode the HIV-1 Env protein and are infectious to macaques have many strains that show different pathogenesis, such as the highly pathogenic SHIV-KS661 and the less pathogenic SHIV-#64. Therefore, we used SHIVs to understand different aspects of AIDS pathogenesis. In a previous study, we established a mathematical model of in vivo early SHIV infection dynamics, which revealed the expected uninfected and infected dynamics in Rhesus macaques. In concrete, the number of uninfected CD4+ T cells in SHIV-KS661-infected Rhesus macaques decreased more significantly and rapidly than that of SHIV-#64 Rhesus macaques, and these Rhesus macaques did not any induce host immune response. In contrast, the number of uninfected CD4+ T cells in SHIV-#64-infected Rhesus macaques is maintained, and host immune response developed. Although we considered that the peak viral load might determine whether systemic CD4+ T cell depletion occurs or host immune responses develop, we could not investigate this because our model quantified only SHIV infection prior to the development of the pathogenicity or host immune responses. Therefore, we developed a new mathematical model to investigate why SHIV-#64 and SHIV-KS661 showed different long-term viral dynamics. We fitted our new model considering antibody responses to our experimental datasets that included antibody titers, CD4+ T cells, and viral load data. We performed a maximum likelihood estimation using a non-linear mixed effect model. From the results, we derived the basic reproduction numbers of SHIV-#64 and SHIV-KS661 from intravenous infection (IV) and SHIV-KS661 from intrarectal infection (IR), as well as the antiviral effects of antibodies against SHIV-#64(IV) and SHIV-KS661(IR). We found significant differences between the basic reproduction number of SHIV-#64(IV) or -KS661(IR) and that of SHIV-KS661(IV). We found no clear difference between the antiviral effects of SHIV-#64(IV) and SHIV-KS661(IR), and revealed that an antiviral effect more than 90% of that of maximum antibody responses was induced from initial antibody responses (i.e., antibody response just after its inducement). In conclusion, we found that the basic reproduction number, rather than SHIV strains determines whether systemic CD4+ T cell depletion develops, and the subsequent antibody responses occurs.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Animales , Antivirales , Humanos , Inmunidad , Macaca mulatta , Carga Viral
20.
Bioorg Med Chem Lett ; 49: 128284, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34311085

RESUMEN

Jasmonic acid (JA) is a plant hormone involved in the defense response against insects and fungi. JA is synthesized from α-linolenic acid (LA) by the octadecanoid pathway in plants. 12-oxo-Phytodienoic acid (OPDA) is one of the biosynthetic intermediates in this pathway. The reported stereo selective total synthesis of cis-(+)-OPDA is not very efficient due to the many steps involved in the reaction as well as the use of water sensitive reactions. Therefore, we developed an enzymatic method for the synthesis of OPDA using acetone powder of flax seed and allene oxide cyclase (PpAOC2) from Physcomitrella patens. From this method, natural cis-(+)-OPDA can be synthesized in the high yield of approximately 40%. In this study, we investigated the substrate specificity of the enzymatic synthesis of other OPDA analogs with successions to afford OPDA amino acid conjugates, dinor-OPDA (dn-OPDA), and OPDA monoglyceride, and it was suggested that the biosynthetic pathway of arabidopsides could occur via MGDG.


Asunto(s)
Ácidos Grasos Insaturados/síntesis química , Oxidorreductasas Intramoleculares/química , Proteínas de Plantas/química , Bryopsida/enzimología , Lino/enzimología , Semillas/enzimología , Estereoisomerismo
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