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1.
Photochem Photobiol Sci ; 23(6): 1041-1050, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38714585

RESUMEN

Near-infrared two-photon absorption and excited state dynamics of a fluorescent diarylethene (fDAE) derivative were investigated by time-resolved absorption and fluorescence spectroscopies. Prescreening with quantum chemical calculation predicted that a derivative with methylthienyl groups (mt-fDAE) in the closed-ring isomer has a two-photon absorption cross-section larger than 1000 GM, which was experimentally verified by Z-scan measurements and excitation power dependence in transient absorption. Comparison of transient absorption spectra under one-photon and simultaneous two-photon excitation conditions revealed that the closed-ring isomer of mt-fDAE populated into higher excited states deactivates following three pathways on a timescale of ca. 200 fs: (i) the cycloreversion reaction more efficient than that by the one-photon process, (ii) internal conversion into the S1 state, and (iii) relaxation into a lower state (S1' state) different from the S1 state. Time-resolved fluorescence measurements demonstrated that this S1' state is relaxed to the S1 state with the large emission probability. These findings obtained in the present work contribute to extension of the ON-OFF switching capability of fDAE to the biological window and application to super-resolution fluorescence imaging in a two-photon manner.

3.
Int J Hematol ; 117(4): 598-606, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36515795

RESUMEN

Mutations in the MECOM encoding EVI1 are observed in infants who have radioulnar synostosis with amegakaryocytic thrombocytopenia. MECOM-associated syndrome was proposed based on clinical heterogeneity. Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative treatment for progressive bone marrow failure. However, data regarding allogeneic HSCT for this rare disease are limited. We retrospectively assessed overall survival, conditioning regimen, regimen-related toxicities and long-term sequelae in six patients treated with allogeneic HSCT. All patients received a reduced-intensity conditioning (RIC) regimen consisting of fludarabine, cyclophosphamide or melphalan, and rabbit anti-thymocyte globulin and/or low-dose total body/thoracic-abdominal/total lymphoid irradiation, followed by allogeneic bone marrow or cord blood transplantation from unrelated donors between 4 and 18 months of age. All patients survived and achieved stable engraftment and complete chimerization with the donor type. Moreover, no patient experienced severe regimen-related toxicities, and only lower grades of acute graft-versus-host disease were observed. Three patients treated with low-dose irradiation had relatively short stature compared to three patients not treated with irradiation. Therefore, allogeneic HSCT with RIC is an effective and feasible treatment for infants with MECOM-associated syndrome. Future studies are needed to evaluate the use of low-dose irradiation to avoid risks of other long-term sequelae.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Humanos , Estudios Retrospectivos , Trasplante Homólogo , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Médula Ósea , Factores de Transcripción , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/prevención & control , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Donante no Emparentado , Acondicionamiento Pretrasplante , Vidarabina/uso terapéutico , Proteína del Locus del Complejo MDS1 y EV11
4.
Chemistry ; 29(13): e202203651, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36524776

RESUMEN

Green-to-blue triplet-triplet annihilation photon upconversion with the well-studied upconversion pair 9,10-diphenylanthracene (DPA)/platinum octaethylporphyrin (PtOEP) was used to reversibly drive the photoisomerization of diarylethene (DAE) photoswitches by using visible light. By carefully selecting the kinetic and spectral properties of the molecular system as well as the experimental geometry, a single green light source can be used to selectively trigger both the ring-opening and the ring-closing reactions, whilst also inducing fluorescence from the colored closed isomer that can be used as a readout to monitor the isomerization process in situ. The upconversion solution and the DAE solution are kept physically separated, allowing them to be characterized both concomitantly and individually without further separation processes. The ring-closing reaction using upconverted photons was quantified and compared to the efficiency of direct isomerization with ultraviolet light.

6.
J Phys Chem Lett ; 13(32): 7429-7436, 2022 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-35929722

RESUMEN

Photoswitching molecules that reversibly switch upon visible-light irradiation are some of the most attractive targets for biological and imaging applications. In this study, we found a diarylethene (DAE) derivative having a covalently attached perylenebisimide (PBI) unit (DAE-PBI dyad) underwent an unexpected cyclization reaction upon irradiation with green (500-550 nm) light, where the DAE unit has no absorbance. The photoreactivity was enhanced in solvents containing heavy atoms and in the presence of oxygen. As inferred from the solvent dependence and the calculated excited-state energies of DAE and PBI units, it was suggested that the probable mechanism for this unique visible-light-induced cyclization reaction is multiplicity conversion based on intramolecular energy transfer from the excited singlet state of the PBI unit to the triplet state of DAE units (i.e., DAE-1[PBI]* → 3[DAE]*-PBI). Such a unique photoreaction mechanism with the assistance of oxygen will pave the way for new molecular design for the development of visible-light switching molecules.


Asunto(s)
Luz , Oxígeno , Ciclización , Transferencia de Energía , Solventes
7.
Case Rep Oncol ; 15(2): 541-546, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35813702

RESUMEN

A 7-year-6-month-old female was diagnosed with a pelvic malignant peripheral nerve sheath tumor and lymph node metastases. Tumorectomy was performed after four cycles of chemotherapy. A 33-mm cystic lesion was observed around the left iliac muscle after three cycles of postoperative chemotherapy, and proton beam therapy (PBT) was recommended. She was referred for absorbable spacer (AS) placement. The left ovarian appendage (OA) was resected due to the direct tumor infiltration. The right OA was fixed to the uterosacral ligament. The AS was fixed to the lateral pelvis. The PBT (70.3 Gy relative biological effectiveness) was performed successfully with the AS, and she also had the reproducing possibility due to prevention of severe irradiation damage of the right OA. AS eliminated the surgical removal of spacers and enabled us high-dose PBT for residual tumor without severe irradiation damage including infertility.

8.
Chem Commun (Camb) ; 58(30): 4715-4718, 2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35377375

RESUMEN

This paper presents a strategy for improving the all-visible-light switching response of turn-on mode fluorescent diarylethene derivatives. Introduction of neopentyl or isobutyl substituents at the reactive carbons (2- and 2'-positions) of an oxidized bis(benzothienyl)perfluorocyclopentene derivative, which undergoes both cyclization and cycloreversion reactions upon irradiation with visible light, was effective in increasing the cycloreversion quantum yield by one or two orders of magnitude in comparison with the yield of an ethyl-substituted derivative. Any significant influence on the cyclization and fluorescence quantum yields was not observed by the introduction of neopentyl or isobutyl substituents.

11.
Cancer Rep (Hoboken) ; 5(8): e1579, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34725963

RESUMEN

BACKGROUND: Better therapeutic options other than conventional chemotherapy for pediatric patients with refractory Langerhans cell histiocytosis (LCH) remain undetermined. CASE: We successfully treated two patients with refractory and risk organ negative LCH with clofarabine (CLO) monotherapy after recurrence. We administered total 23 courses of CLO monotherapy in patient 1 and 4 courses in patient 2. Both patients had distinct clinical manifestations but achieved a durable complete response with acceptable adverse effects of transient myelosuppression. CLO monotherapy was still effective when he had the second recurrent lesion after first completion of CLO in patient 1. We could discontinue prednisolone to control his refractory inflammation of LCH after completing CLO chemotherapy in patient 2. CONCLUSION: Although large-scale studies are warranted, CLO monotherapy could be a therapeutic option for high efficacy and feasibility besides other intensive combination chemotherapies or allogeneic hematopoietic stem cell transplantation for refractory LCH without risk organ involvement in children.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Histiocitosis de Células de Langerhans , Niño , Clofarabina/uso terapéutico , Histiocitosis de Células de Langerhans/diagnóstico , Histiocitosis de Células de Langerhans/tratamiento farmacológico , Humanos , Masculino , Inducción de Remisión
12.
Proc Natl Acad Sci U S A ; 118(43)2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34663725

RESUMEN

Early identification of atypical infant movement behaviors consistent with underlying neuromotor pathologies can expedite timely enrollment in therapeutic interventions that exploit inherent neuroplasticity to promote recovery. Traditional neuromotor assessments rely on qualitative evaluations performed by specially trained personnel, mostly available in tertiary medical centers or specialized facilities. Such approaches are high in cost, require geographic proximity to advanced healthcare resources, and yield mostly qualitative insight. This paper introduces a simple, low-cost alternative in the form of a technology customized for quantitatively capturing continuous, full-body kinematics of infants during free living conditions at home or in clinical settings while simultaneously recording essential vital signs data. The system consists of a wireless network of small, flexible inertial sensors placed at strategic locations across the body and operated in a wide-bandwidth and time-synchronized fashion. The data serve as the basis for reconstructing three-dimensional motions in avatar form without the need for video recordings and associated privacy concerns, for remote visual assessments by experts. These quantitative measurements can also be presented in graphical format and analyzed with machine-learning techniques, with potential to automate and systematize traditional motor assessments. Clinical implementations with infants at low and at elevated risks for atypical neuromotor development illustrates application of this system in quantitative and semiquantitative assessments of patterns of gross motor skills, along with body temperature, heart rate, and respiratory rate, from long-term and follow-up measurements over a 3-mo period following birth. The engineering aspects are compatible for scaled deployment, with the potential to improve health outcomes for children worldwide via early, pragmatic detection methods.


Asunto(s)
Conducta del Lactante/fisiología , Monitoreo Fisiológico/instrumentación , Movimiento/fisiología , Signos Vitales/fisiología , Tecnología Inalámbrica/instrumentación , Sesgo , Niño , Diseño de Equipo , Frecuencia Cardíaca , Humanos , Imagenología Tridimensional , Lactante , Miniaturización , Monitoreo Fisiológico/estadística & datos numéricos , Frecuencia Respiratoria , Piel , Grabación en Video , Tecnología Inalámbrica/estadística & datos numéricos
13.
Adv Healthc Mater ; 10(17): e2100383, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33938638

RESUMEN

Indwelling arterial lines, the clinical gold standard for continuous blood pressure (BP) monitoring in the pediatric intensive care unit (PICU), have significant drawbacks due to their invasive nature, ischemic risk, and impediment to natural body movement. A noninvasive, wireless, and accurate alternative would greatly improve the quality of patient care. Recently introduced classes of wireless, skin-interfaced devices offer capabilities in continuous, precise monitoring of physiologic waveforms and vital signs in pediatric and neonatal patients, but have not yet been employed for continuous tracking of systolic and diastolic BP-critical for guiding clinical decision-making in the PICU. The results presented here focus on materials and mechanics that optimize the system-level properties of these devices to enhance their reliable use in this context, achieving full compatibility with the range of body sizes, skin types, and sterilization schemes typically encountered in the PICU. Systematic analysis of the data from these devices on 23 pediatric patients, yields derived, noninvasive BP values that can be quantitatively validated against direct recordings from arterial lines. The results from this diverse cohort, including those under pharmacological protocols, suggest that wireless, skin-interfaced devices can, in certain circumstances of practical utility, accurately and continuously monitor BP in the PICU patient population.


Asunto(s)
Cuidados Críticos , Signos Vitales , Presión Sanguínea , Niño , Humanos , Recién Nacido , Monitoreo Fisiológico , Piel
14.
Proc Natl Acad Sci U S A ; 118(14)2021 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-33782137

RESUMEN

The use of photoswitchable fluorescent diarylethenes (fDAEs) as protein labels in fluorescence microscopy and nanoscopy has been limited by labeling inhomogeneity and the need for ultraviolet light for fluorescence activation (on-switching). To overcome these drawbacks, we prepared "turn-on mode" fDAEs featuring thienyl substituents, multiple polar residues, and a reactive maleimide group in the core structure. Conjugates with antibodies and nanobodies displayed complete on-switching and excitation with violet (405 nm) and yellow-green (<565 nm) light, respectively. Besides, they afforded high signal-to-noise ratios and low unspecific labeling in fluorescence imaging. Irradiation with visible light at 532 nm or 561 nm led to transient on-off switching ("blinking") of the fDAEs of double-labeled nanobodies so that nanoscale superresolution images were readily attained through switching and localization of individual fluorophores.


Asunto(s)
Colorantes Fluorescentes/síntesis química , Procesos Fotoquímicos , Anticuerpos/química , Línea Celular Tumoral , Colorantes Fluorescentes/efectos de la radiación , Humanos , Maleimidas/química , Microscopía Fluorescente/métodos , Compuestos de Sulfhidrilo/química , Rayos Ultravioleta
15.
Polymers (Basel) ; 13(2)2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33467478

RESUMEN

Depositing minute light emitters into a regular array is a basic but essential technique in display technology. However, conventional lithographic methodologies involve multistep and energy-consuming processes. Here, we develop a facile method in which organic and polymeric fluorescent dyes spontaneously aggregate to form a patterned microarray. We find that a thin film of fluorescent π-conjugated polymer transforms into micrometer-sized aggregates when exposed to binary organic vapor at ambient temperature. The arrayed microaggregates can be formed over the whole substrate surface when using a quartz substrate that is prepatterned with regular hydrophilic boxes and hydrophobic grids. The resultant microarray is applicable to optical memories and displays when photoswitchable fluorophores are doped into the polymer matrix.

16.
BME Front ; 2021: 8653218, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-37849909

RESUMEN

Objective and Impact Statement. Real-time monitoring of the temperatures of regional tissue microenvironments can serve as the diagnostic basis for treating various health conditions and diseases. Introduction. Traditional thermal sensors allow measurements at surfaces or at near-surface regions of the skin or of certain body cavities. Evaluations at depth require implanted devices connected to external readout electronics via physical interfaces that lead to risks for infection and movement constraints for the patient. Also, surgical extraction procedures after a period of need can introduce additional risks and costs. Methods. Here, we report a wireless, bioresorbable class of temperature sensor that exploits multilayer photonic cavities, for continuous optical measurements of regional, deep-tissue microenvironments over a timeframe of interest followed by complete clearance via natural body processes. Results. The designs decouple the influence of detection angle from temperature on the reflection spectra, to enable high accuracy in sensing, as supported by in vitro experiments and optical simulations. Studies with devices implanted into subcutaneous tissues of both awake, freely moving and asleep animal models illustrate the applicability of this technology for in vivo measurements. Conclusion. The results demonstrate the use of bioresorbable materials in advanced photonic structures with unique capabilities in tracking of thermal signatures of tissue microenvironments, with potential relevance to human healthcare.

17.
Chemphyschem ; 21(14): 1485, 2020 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-32672424

RESUMEN

The front cover artwork is provided by the groups of Prof. Hiroshi Miyasaka (Osaka University, Japan), Prof. Masahiro Irie (Rikkyo University, Japan), Prof. Seiya Kobatake (Osaka City University, Japan) and Prof. Akira Sakamoto (Aoyama Gakuin University, Japan). The image shows the coherently vibrating closed form of a photochromic diarylethene derivative in the excited state, and subsequent structural evolution into the open form in the cycloreversion reaction. Read the full text of the Article at 10.1002/cphc.202000315.

18.
Chemphyschem ; 21(14): 1524-1530, 2020 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-32489017

RESUMEN

The geometrical evolution of the reactant and formation of the photoproduct in the cycloreversion reaction of a diarylethene derivative were probed using time-resolved absorption spectroscopies in the visible to near-infrared and mid-infrared regions. The time-domain vibrational data in the visible region show that the initially formed Franck-Condon state is geometrically relaxed into the minimum in the excited state potential energy surface, concomitantly with the low-frequency coherent vibrations. Theoretical calculations indicate that the nuclear displacement in this coherent vibration is nearly parallel to that in the geometrical relaxation. Time-resolved mid-infrared spectroscopy directly detected the formation of the open-ring isomer with the same time constant as the decrease of the closed-ring isomer in the excited state minimum. This observation reveals that no detectable intermediate, in which the population is accumulated, is present between the excited closed-ring isomer and the open-ring isomer in the ground state.

19.
J Med Invest ; 67(1.2): 174-181, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32378603

RESUMEN

Background : High blood pressure (BP) is a healthcare problem in young persons. There are racial differences in anthropometrics, dietary habit and lifestyle relating to BP. Therefore, this study investigated the relationship between anthropometrics, lifestyle and BP obtained in the Japanese university students. Materials and Methods : Participants were recruited in annual health screening including questionnaire, measurements of BP and anthropometrics calculating body mass index (BMI). Totally, 14,280 students (10,273 males and 4,007 females) were eligible. Multiple regression analyses were applied to predict contributors to high BP. Results : BMI was the most powerful contributor to high BP in many subgroups divided by gender and graduation (p < 0.001). In lifestyle, contribution of lack of exercise to high BPs was observed in the undergraduates. Smoking, drinking and breakfast skipping had no significant impact on high BP. However, smoking and drinking permeated and exercise habit declined after graduation. Prevalence of obesity (BMI ≥ 25 kg / m2) and hypertension ( ≥ 140 / 90 mmHg) increased in subgroups with advanced age (p < 0.001). Conclusion: BMI was found to be the most powerful contributor to high BPs. Health literacy to modify lifestyle is important to prevent hypertension for university students who are exposed to social trends of unhealthy lifestyle. J. Med. Invest. 67 : 174-181, February, 2020.


Asunto(s)
Presión Sanguínea , Índice de Masa Corporal , Estilo de Vida , Adulto , Factores de Edad , Estudios Transversales , Femenino , Humanos , Hipertensión/etiología , Masculino , Caracteres Sexuales , Estudiantes , Universidades
20.
Int J Hematol ; 112(2): 258-262, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32180118

RESUMEN

Signal transducer and activator of transcription 1 gain-of-function (STAT1 GOF) mutations are the most common cause of chronic mucocutaneous candidiasis (CMC). We report the effect of oral ruxolitinib, an inhibitor of Janus kinase (JAK) family tyrosine kinases, on the clinical and immune status of a 3-year-old male with steroid-dependent severe autoimmunity due to a STAT1 GOF T385M mutation. The patient's susceptibility to infection improved with antimicrobial prophylaxis and immunoglobulin replacement therapy, but he continued to exhibit severely disabling symptoms of autoimmunity. More than one-third of patients with STAT1 GOF mutations present with autoimmune manifestations, and this patient's mutation was reported to cause CMC with autoimmunity. We analyzed the interleukin (IL)-17A and IFN-γ levels and immunophenotype by flow cytometry before and during treatment with ruxolitinib. The peripheral IL-17A level did not increase, but the IFN-γ level decreased after 4 months of therapy. The STAT1 phosphorylation level decreased significantly upon stimulation of patient cells with IFN-γ. Clinically, cytomegalovirus reactivation occurred, but was controlled. No other adverse effect was noted. We report the potential of JAK1/2 inhibition with ruxolitinib for both CMC and steroid-dependent autoimmunity. However, long-term administration is necessary, as the effect is not sustained after treatment is discontinued.


Asunto(s)
Candidiasis Mucocutánea Crónica/tratamiento farmacológico , Candidiasis Mucocutánea Crónica/inmunología , Mutación con Ganancia de Función/genética , Inhibidores de Proteínas Quinasas/administración & dosificación , Pirazoles/administración & dosificación , Factor de Transcripción STAT1/genética , Autoinmunidad , Candidiasis Mucocutánea Crónica/genética , Citocinas/metabolismo , Humanos , Lactante , Janus Quinasa 1/antagonistas & inhibidores , Masculino , Nitrilos , Fosforilación , Pirimidinas , Factor de Transcripción STAT1/metabolismo , Índice de Severidad de la Enfermedad
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