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1.
BMC Med Imaging ; 23(1): 17, 2023 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-36710344

RESUMEN

BACKGROUND: Slot-scan digital radiography (SSDR) is equipped with detachable scatter grids and a variable copper filter. In this study, this function was used to obtain parameters for low-dose imaging for whole-spine imaging. METHODS: With the scatter grid removed and the beam-hardening (BH) filters (0.0, 0.1, 0.2, or 0.3 mm) inserted, the tube voltage (80, 90, 100, 110, or 120 kV) and the exposure time were adjusted to 20 different parameters that produce equivalent image quality. Slot-scan radiographs of an acrylic phantom were acquired with the set parameters, and the optimal parameters (four types) for each filter were determined using the figure of merit. For the four types of parameters obtained in the previous section, SSDR was performed on whole-spine phantoms by varying the tube current, and the parameter with the lowest radiation dose was determined by visual evaluation. RESULTS: The parameters for each filter according to the FOM results were 90 kV, 400 mA, and 2.8 ms for 0.0 mm thickness; 100 kV, 400 mA, and 2.0 ms for 0.1 mm thickness; 100 kV, 400 mA, and 2.8 ms for 0.2 mm thickness; and 110 kV, 400 mA, and 2.2 ms for 0.3 mm thickness. Visual evaluation of the varying tube currents was performed using these four parameters when the BH filter thicknesses were 0.0, 0.1, 0.2, and 0.3 mm. The entrance surface dose was 59.44 µGy at 90 kV, 125 mA, and 2.8 ms; 57.39 µGy at 100 kV, 250 mA, and 2.0 ms; 46.89 µGy at 100 kV, 250 mA, and 2.8 ms; and 39.48 µGy at 110 kV, 250 mA, and 2.2 ms, indicating that the 0.3-mm BH filter was associated with the minimum dose. CONCLUSION: Whole-spine SSDR could reduce the dose by 79% while maintaining the image quality.


Asunto(s)
Intensificación de Imagen Radiográfica , Humanos , Intensificación de Imagen Radiográfica/métodos , Dosis de Radiación , Fantasmas de Imagen , Cintigrafía
2.
JMIR Res Protoc ; 12: e42032, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36716091

RESUMEN

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder, with its currently approved drugs, including riluzole and edaravone, showing limited therapeutic effects. Therefore, safe and effective drugs are urgently necessary. EPI-589 is an orally available, small-molecule, novel redox-active agent characterized by highly potent protective effects against oxidative stress with high blood-brain barrier permeability. Given the apparent oxidative stress and mitochondrial dysfunction involvement in the pathogenesis of ALS, EPI-589 may hold promise as a therapeutic agent. OBJECTIVE: This protocol aims to describe the design and rationale for the EPI-589 Early Phase 2 Investigator-Initiated Clinical Trial for ALS (EPIC-ALS). METHODS: EPIC-ALS is an explorative, open-labeled, single-arm trial that evaluates the safety and tolerability of EPI-589 in patients with ALS. This trial consists of 12-week run-in, 24-week treatment, and 4-week follow-up periods. Patients will receive 500 mg of EPI-589 3 times daily over the 24-week treatment period. Clinical assessments include the mean monthly change of Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised total score. The biomarkers are selected to analyze the effect on oxidative stress and neuronal damage. The plasma biomarkers are 8-hydroxy-2'-deoxyguanosine (8-OHdG), 3-nitrotyrosine (3-NT), neurofilament light chain (NfL), phosphorylated neurofilament heavy chain (pNfH), homocysteine, and creatinine. The cerebrospinal fluid biomarkers are 8-OHdG, 3-NT, NfL, pNfH, and ornithine. The magnetic resonance biomarkers are fractional anisotropy in the corticospinal tract and N-acetylaspartate in the primary motor area. RESULTS: This trial began data collection in September 2021 and is expected to be completed in October 2023. CONCLUSIONS: This study can provide useful data to understand the characteristics of EPI-589. TRIAL REGISTRATION: Japan Primary Registries Network jRCT2061210031; tinyurl.com/2p84emu6. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/42032.

3.
JAMA Neurol ; 79(6): 575-583, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35532908

RESUMEN

Importance: The effectiveness of currently approved drugs for amyotrophic lateral sclerosis (ALS) is restricted; there is a need to develop further treatments. Initial studies have shown ultrahigh-dose methylcobalamin to be a promising agent. Objective: To validate the efficacy and safety of ultrahigh-dose methylcobalamin for patients with ALS enrolled within 1 year of onset. Design, Setting, and Participants: This was a multicenter, placebo-controlled, double-blind, randomized phase 3 clinical trial with a 12-week observation and 16-week randomized period, conducted from October 17, 2017, to September 30, 2019. Patients were recruited from 25 neurology centers in Japan; those with ALS diagnosed within 1 year of onset by the updated Awaji criteria were initially enrolled. Of those, patients fulfilling the following criteria after 12-week observation were eligible for randomization: 1- or 2-point decrease in the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) total score, a percent forced vital capacity greater than 60%, no history of noninvasive respiratory support and tracheostomy, and being ambulatory. The target participant number was 64 in both the methylcobalamin and placebo groups. Patients were randomly assigned through an electronic web-response system to methylcobalamin or placebo. Interventions: Intramuscular injection of methylcobalamin (50-mg dose) or placebo twice weekly for 16 weeks. Main Outcomes and Measures: The primary end point was change in ALSFRS-R total score from baseline to week 16 in the full analysis set. Results: A total of 130 patients (mean [SD] age, 61.0 [11.7] years; 74 men [56.9%]) were randomly assigned to methylcobalamin or placebo (65 each). A total of 129 patients were eligible for the full analysis set, and 126 completed the double-blind stage. Of these, 124 patients proceeded to the open-label extended period. The least square means difference in ALSFRS-R total score at week 16 of the randomized period was 1.97 points greater with methylcobalamin than placebo (-2.66 vs -4.63; 95% CI, 0.44-3.50; P = .01). The incidence of adverse events was similar between the 2 groups. Conclusions and Relevance: Results of this randomized clinical trial showed that ultrahigh-dose methylcobalamin was efficacious in slowing functional decline in patients with early-stage ALS and with moderate progression rate and was safe to use during the 16-week treatment period. Trial Registration: ClinicalTrials.gov Identifier: NCT03548311.


Asunto(s)
Esclerosis Amiotrófica Lateral , Esclerosis Amiotrófica Lateral/diagnóstico , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Método Doble Ciego , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Capacidad Vital , Vitamina B 12/análogos & derivados , Vitamina B 12/uso terapéutico
4.
Educ Inf Technol (Dordr) ; 27(7): 10371-10386, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35464114

RESUMEN

Owing to the coronavirus disease 2019 (COVID-19) pandemic, understanding how to hold future online academic conferences effectively is imperative. We assessed the impact of COVID-19 on academic conferences, including facilities and settings for attendance, participation status, cost burden, and preferences for future styles of holding conferences, through a web-based questionnaire survey of 2,739 Japanese medical professionals, from December 2020 to February 2021. Of the participants, 28% preferred web conferences, 60% preferred a mix of web and on-site conferences, and 12% preferred on-site conferences. Additionally, 27% of the presenters stopped presenting new findings at web conferences. The proportion of participants who audio-recorded or filmed the sessions, despite prohibition, was six times higher at web than face-to-face conferences. Since the COVID-19 outbreak, the percentage of participants attending general presentations decreased from 91 to 51%. While web conferencing offers advantages, these are offset by a decrease in presentations pertaining to novel findings and data. Supplementary Information: The online version contains supplementary material available at 10.1007/s10639-022-11032-5.

5.
Biol Pharm Bull ; 45(3): 374-377, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35228403

RESUMEN

In April 2018, the Clinical Trials Act pertaining to investigator-initiated clinical trials was passed in Japan. The purpose of this study was to investigate activity in investigator-initiated clinical studies before and after enforcement of the new Clinical Trials Act. This was done by analysing the records of the Ethics Committee of Tokushima University Hospital, which reviews studies based on the Japanese government's Ethical Guidelines for Medical and Health Research Involving Human Subjects prior to the Clinical Trials Act, and records of the Certified Review Board established at Tokushima University under the Clinical Trials Act in 2018. The number of new applications to these two review boards during fiscal years 2015-2017 (pre-Act) and fiscal years 2018 and 2019 (post-Act) were used as an indicator of activity in investigator-initiated clinical studies. The number of new applications to the Ethics Committee was 303, 261, 316, 303, and 249 in 2015, 2016, 2017, 2018, and 2019, respectively. The data show that the total number of new interventional studies decreased from 50.3 in average in 2015-2017 (pre-Act) to 42 in 2018 and 40 in 2019 (post-Act), respectively. These results suggest that fewer interventional studies were started following enforcement of the new Clinical Trials Act. To confirm this trend and identify contributing factors, further studies are required. In addition, possible way, such as broader contribution of clinical research coordinators, to promote clinical studies in the new Clinical Trials Act era should be examined.


Asunto(s)
Ensayos Clínicos como Asunto , Hospitales Universitarios , Ensayos Clínicos como Asunto/legislación & jurisprudencia , Humanos , Japón
6.
J Med Invest ; 68(1.2): 71-75, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33994483

RESUMEN

Background : Enforcement of the 2018 Clinical Trials Act (CTA) in Japan resulted in strict and complicated regulations surrounding intervention studies. Few Japan-specific measures have been developed to promote intervention studies in Japan despite concerns about CTA's negative influence on such studies. Therefore, this study examined the changes in academic investigators' interest in conducting clinical studies before and after enforcement of the CTA to determine measures to promote specified clinical trials. Methods : We conducted a questionnaire survey with investigators belonging to the Institute of Biomedical Sciences, Tokushima University Graduate School, before and after enforcement of the CTA. Results : Investigators had lesser interest in intervention studies in the post-questionnaire survey (post) group than in the pre-questionnaire survey (pre) group. Their desire for "project management" was significantly higher in the post-group than in the pre-group. Their desire for "support for preparing documents when conducting specified clinical trials" was significantly higher in the group interested in conducting specified clinical trials than that in the not-interested group. Conclusion : We revealed that investigators were highly interested in "project management" and "support for preparing documents when conducting specified clinical trials" after enforcement of the CTA. Measures for these desires may promote specified clinical trials. J. Med. Invest. 68 : 71-75, February, 2021.


Asunto(s)
Universidades , Ensayos Clínicos como Asunto , Humanos , Japón , Encuestas y Cuestionarios
7.
J Med Internet Res ; 22(11): e22302, 2020 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-33112758

RESUMEN

BACKGROUND: With the global proliferation of the novel COVID-19 disease, conventionally conducting institutional review board (IRB) meetings has become a difficult task. Amid concerns about the suspension of drug development due to delays within IRBs, it has been suggested that IRB meetings should be temporarily conducted via the internet. OBJECTIVE: This study aimed to elucidate the current status of IRB meetings conducted through web conference systems. METHODS: A survey on conducting IRB meetings through web conference systems was administered to Japanese national university hospitals. Respondents were in charge of operating IRB offices at different universities. This study was not a randomized controlled trial. RESULTS: The survey was performed at 42 facilities between the end of May and early June, 2020, immediately after the state of emergency was lifted in Japan. The survey yielded a response rate of 74% (31/42). Additionally, while 68% (21/31) of facilities introduced web conference systems for IRB meetings, 13% (4/31) of the surveyed facilities postponed IRB meetings. Therefore, we conducted a further survey of 21 facilities that implemented web conference systems for IRB meetings. According to 71% (15/21) of the respondents, there was no financial burden for implementing these systems, as they were free of charge. In 90% (19/21) of the facilities, IRB meetings through web conference systems were already being conducted with personal electronic devices. Furthermore, in 48% (10/21) of facilities, a web conference system was used in conjunction with face-to-face meetings. CONCLUSIONS: Due to the COVID-19 pandemic, the number of reviews in clinical trial core hospitals has decreased. This suggests that the development of pharmaceuticals has stagnated because of COVID-19. According to 71% (15/21) of the respondents who conducted IRB meetings through web conference systems, the cost of introducing such meetings was US $0, showing a negligible financial burden. Moreover, it was shown that online deliberations could be carried out in the same manner as face-to-face meetings, as 86% (18/21) of facilities stated that the number of comments made by board members did not change. To improve the quality of IRB meetings conducted through web conference systems, it is necessary to further examine camera use and the content displayed on members' screens during meetings. Further examination of all members who use web conference systems is required. Our measures for addressing the requests and problems identified in our study could potentially be considered protocols for future IRB meetings, when the COVID-19 pandemic has passed and face-to-face meetings are possible again. This study also highlights the importance of developing web conference systems for IRB meetings to respond to future unforeseen pandemics.


Asunto(s)
Infecciones por Coronavirus , Comités de Ética en Investigación/estadística & datos numéricos , Hospitales Universitarios , Internet , Pandemias , Neumonía Viral , Encuestas y Cuestionarios , Comunicación por Videoconferencia/estadística & datos numéricos , COVID-19 , Infecciones por Coronavirus/epidemiología , Comités de Ética en Investigación/organización & administración , Humanos , Japón/epidemiología , Neumonía Viral/epidemiología , Comunicación por Videoconferencia/organización & administración
8.
JMIR Res Protoc ; 7(12): e12046, 2018 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-30578206

RESUMEN

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that affects the upper and lower motor neurons. Currently, only riluzole and edaravone are approved as drugs to treat ALS and new agents with larger effect sizes are warranted. Exploratory analyses in our previous study (study ID #E0302-J081-761) have suggested that high-dose methylcobalamin (E0302) prolonged the overall survival of ALS patients and suppressed ALS progression in patients with a disease duration of less than 12 months. OBJECTIVE: This clinical trial aims to evaluate the efficacy and safety of E0302 for treatment of ALS patients within one year of onset. METHODS: The Japanese early-stage trial of high-dose methylcobalamin for ALS (JETALS) is a prospective, multicenter, placebo-controlled, double-blind, randomized phase III study conducted at 24 tertiary neurology centers and is funded by the Japan Agency for Medical Research and Development. A total of 128 ALS patients within one year of onset were randomized at a 1:1 ratio to receive intramuscular injection with E0302 50 mg or placebo twice a week for 16 weeks. The primary endpoint is changes in the ALS Functional Rating Scale-Revised (ALSFRS-R) total score at 16 weeks. If patients wish to receive E0302 50 mg after the double-blind administration period, E0302 will be provided to them until March 2020 during the continuous administration period. RESULTS: This study began in October 2017 and is being conducted at 24 participating institutions in Japan. The study is in progress and the patient enrollment period is scheduled to end in August 2019, with follow-up scheduled to end in March 2020. CONCLUSIONS: This study is being performed to revalidate the efficacy and safety of E0302 in patients with early-stage ALS in the first year of symptom onset. If positive results are obtained, the aim is to apply for E0302 approval as a new drug for the treatment of ALS. TRIAL REGISTRATION: ClinicalTrials.gov NCT03548311; https://clinicaltrials.gov/ct2/show/NCT03548311 (Archived by WebCite at http://www.webcitation.org/74Fw3rDzb). INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/12046.

9.
Eur J Haematol ; 82(5): 398-403, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19220419

RESUMEN

We report a follicular lymphoma (FL) case presenting the coexistence of two tumor cell subpopulations in lymph node (LN) and bone marrow (BM), which exhibited an inverse pattern of immunoglobulin light (IgL) chain gene rearrangement and expression: Igkappa-lambda+ in LN and Igkappa+lambda- in BM. These tumor clones shared an identical BCL2-IgH recombination, accompanying t(14;18)(q32;q21) translocation, and an identical variable, diversity and joining segments joining with clone-specific VH somatic hypermutations on the untranslocated IgH allele. Our study provides further evidence that FL clones, originating from common progenitor cells, can be developed independently at different sites and with different IgL expression after immune selection.


Asunto(s)
Médula Ósea/patología , Linfoma Folicular/patología , Linaje de la Célula , Células Clonales/patología , Femenino , Genes de las Cadenas Ligeras de las Inmunoglobulinas , Humanos , Persona de Mediana Edad
10.
Plant Physiol ; 149(2): 708-18, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19098091

RESUMEN

Nicotine is a major alkaloid accumulating in the vacuole of tobacco (Nicotiana tabacum), but the transporters involved in the vacuolar sequestration are not known. We here report that tobacco genes (NtMATE1 and NtMATE2) encoding transporters of the multidrug and toxic compound extrusion (MATE) family are coordinately regulated with structural genes for nicotine biosynthesis in the root, with respect to spatial expression patterns, regulation by NIC regulatory loci, and induction by methyl jasmonate. Subcellular fractionation, immunogold electron microscopy, and expression of a green fluorescent protein fusion protein all suggested that these transporters are localized to the vacuolar membrane. Reduced expression of the transporters rendered tobacco plants more sensitive to the application of nicotine. In contrast, overexpression of NtMATE1 in cultured tobacco cells induced strong acidification of the cytoplasm after jasmonate elicitation or after the addition of nicotine under nonelicited conditions. Expression of NtMATE1 in yeast (Saccharomyces cerevisiae) cells compromised the accumulation of exogenously supplied nicotine into the yeast cells. The results imply that these MATE-type proteins transport tobacco alkaloids from the cytosol into the vacuole in exchange for protons in alkaloid-synthesizing root cells.


Asunto(s)
Resistencia a Múltiples Medicamentos/genética , Nicotiana/genética , Nicotiana/fisiología , Nicotina/metabolismo , Nicotina/toxicidad , Proteínas de Transporte de Catión Orgánico/metabolismo , Raíces de Plantas/fisiología , Vacuolas/fisiología , Alcaloides/metabolismo , Alcaloides/toxicidad , Clonación Molecular , Ciclopentanos/metabolismo , ADN Complementario/genética , ADN de Plantas/genética , Genes Reporteros , Proteínas Fluorescentes Verdes/genética , Datos de Secuencia Molecular , Proteínas de Transporte de Catión Orgánico/genética , Oxilipinas/metabolismo , Raíces de Plantas/efectos de los fármacos , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Nicotiana/efectos de los fármacos , Transfección , Vacuolas/efectos de los fármacos
11.
Rinsho Ketsueki ; 48(8): 642-6, 2007 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-17867301

RESUMEN

A 60-year-old man was admitted with muscle weakness and numbness in the extremities. Based on the existence of monoclonal gammopathy of the IgG-lamda type, a slight increase of plasma cells in the bone marrow, and an elevated level of serum vascular endothelial growth factor (VEGF), the diagnosis of POEMS syndrome was made. After peripheral blood stem cell collection by etoposide and G-CSF, the patient received high dose melphalan (200 mg/m2) therapy supported by autologous peripheral blood stem cell transplantation (autoPBSCT). After high-dose chemotherapy with autoPBSCT, the serum VEGF level normalized and the monoclonal IgG-lamda, disappeared. The patient gradually recovered from a bedridden state and at the time of writing has no impairment in his activities of daily life. After the autoPBSCT, monoclonal IgG-kappa, protein was detected transiently in serum. The new monoclonal immunoglobulin was considered to be due to normal immune reconstitution after myeloablation rather than alteration of the abnormal plasma cell clone, similarly as oligoclonal immunoglobulins occur in multiple myeloma after autoPBSCT. AutoPBSCT with high-dose chemotherapy should be considered among the treatments of choice for POEMS syndrome.


Asunto(s)
Síndrome POEMS/inmunología , Síndrome POEMS/terapia , Trasplante de Células Madre de Sangre Periférica , Humanos , Inmunoglobulina G/sangre , Cadenas kappa de Inmunoglobulina/sangre , Masculino , Persona de Mediana Edad , Trasplante Autólogo
12.
Rinsho Ketsueki ; 46(7): 536-8, 2005 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-16440749

RESUMEN

A 61-year-old man with primary macroglobulinemia (PMG) had been followed without any treatment as he had no apparent manifestations. After 1 year and 3 months, he was admitted to our hospital with a fever. No signs or symptoms of infection and no progressive increase of serum IgM levels was observed. Non-Hodgkin's lymphoma was not additionally found. Fever without infection, elevated serum LDH level and further enlargement of the spleen compelled us to diagnose his condition as deterioration of the PMG. An immediate fall in his temperature and serum IgM levels was observed after CHOP therapy. Effective therapy must be discussed in the deterioration of this type of disease.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Inmunoglobulina M/sangre , Macroglobulinemia de Waldenström/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Biomarcadores/sangre , Ciclofosfamida/administración & dosificación , Progresión de la Enfermedad , Doxorrubicina/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Prednisolona/administración & dosificación , Resultado del Tratamiento , Vincristina/administración & dosificación , Macroglobulinemia de Waldenström/diagnóstico
13.
Rinsho Ketsueki ; 46(6): 458-62, 2005 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-16447728

RESUMEN

A 62-year-old woman was admitted to our hospital because of gastric mucosal bleeding. Gastroendoscopy revealed a gastric tumor which was diagnosed from the biopsied specimen as diffuse large B-cell lymphoma (DLBCL). Lymphoma cells had infiltrated the bone marrow showed morphological features resembling Burkitt lymphoma (BL). Nearly 100% of the cells in the bone marrow were positive for MIB-1 immunostaining. The chromosomal study was normal. Surface marker analysis disclosed that the cells were positive for CD10, CD19, CD20 and CD25. As lymphoma cells had infiltrated the central nervous system, combined chemotherapy was performed accompanied with intrathecal administration of anticancer drugs. Although transient improvement was observed, the patient died of the advanced disease three months after admission. As we have shown here, there are some cases of DLBCL with immunohistochemical features resembling BL. Further consideration about the appropriate chemotherapy program for this type of disease might be necessary.


Asunto(s)
Antígeno Ki-67/análisis , Linfoma de Células B/diagnóstico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores/análisis , Linfoma de Burkitt , Terapia Combinada , Diagnóstico Diferencial , Progresión de la Enfermedad , Resultado Fatal , Femenino , Humanos , Linfoma de Células B/patología , Linfoma de Células B/terapia , Linfoma de Células B Grandes Difuso , Persona de Mediana Edad
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