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1.
Chemistry ; 30(18): e202304238, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38270276

RESUMEN

Saxitoxin (STX, 1) is a representative compound of paralytic shellfish toxins (PSTs) that are produced by marine dinoflagellates and freshwater cyanobacteria. Although several pathways have been proposed for the biosynthesis of STX, the order of ring and side chain hydroxylation, and formation of the tricyclic skeleton have not been well established. In this study, 12,12-dideoxy-decarbamoyloxySTX (dd-doSTX, 2), the most reduced STX analogue having the tricyclic skeleton, and its analogues, 12ß-deoxy-doSTX (12ß-d-doSTX, 3), 12α-deoxy-doSTX (12α-d-doSTX, 4), and doSTX (5), were synthesized, and these compounds were screened in the toxic microalgae using high-resolution LCMSMS. dd-doSTX (2) and 12ß-d-doSTX (3) were identified in the PSTs-producing dinoflagellates (Alexandrium catenella, A. pacificum, and/or Gymnodinium catenatum) and in the cyanobacterium Dolichospermum circinale (TA04). doSTX (5), previously isolated from the dinoflagellate G. catenatum, was also identified in D. circinale (TA04). Furthermore, the conversion of 2 to 3, and 4 to 5, by SxtT with VanB, a reported Rieske oxygenase and its redox partner in STX biosynthesis, was confirmed. These results support that 2 is a possible biosynthetic precursor of STX, and that ring and side-chain hydroxylations proceed after cyclization.


Asunto(s)
Dinoflagelados , Microalgas , Saxitoxina/análogos & derivados , Saxitoxina/química , Oxigenasas
2.
Pediatr Nephrol ; 39(3): 905-909, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37572117

RESUMEN

BACKGROUND  : Nephropathy in Denys-Drash syndrome (DDS) develops within a few months of birth, often progressing to kidney failure. Wilms tumors also develop at an early age with a high rate of incidence. When a patient does not have Wilms tumor but develops kidney failure, prophylactic bilateral nephrectomy, and kidney transplantation (KTX) is an optimal approach owing to the high risk of Wilms tumor development. In the case presented here, prophylactic bilateral nephrectomy and KTX were performed in a patient who had not developed Wilms tumor or kidney failure. However, the treatment option is controversial as it involves the removal of a tumor-free kidney and performing KTX in the absence of kidney failure. CASE DIAGNOSIS/TREATMENT: We present the case of a 7-year-old boy, born at 38 weeks gestation. Examinations at the age of 1 year revealed severe proteinuria and abnormal internal and external genitalia. Genetic testing identified a missense mutation in exon 9 of the WT1 gene, leading to the diagnosis of DDS. At the age of 6 years, he had not yet developed Wilms tumor and had grown to a size that allowed him to safely undergo a KTX. His kidney function was slowly deteriorating (chronic kidney disease (CKD) stage 3), but he had not yet developed kidney failure. Two treatment options were considered for this patient: observation until the development of kidney failure or prophylactic bilateral nephrectomy with KTX to avoid Wilms tumor development. After a detailed explanation of options to the patient and family, they decided to proceed with prophylactic bilateral nephrectomy and KTX. At the latest follow-up 4 months after KTX, the patient's kidney functioned well without proteinuria. CONCLUSION: We performed prophylactic bilateral nephrectomy with KTX on a DDS patient who had not developed kidney failure or Wilms tumor by the age of 7 years. Although the risk of development of Wilms tumor in such a patient is unclear, this treatment may be an optimal approach for patients who are physically able to undergo KTX, considering the potentially lethal nature of Wilms tumor in CKD patients.


Asunto(s)
Síndrome de Denys-Drash , Neoplasias Renales , Trasplante de Riñón , Insuficiencia Renal Crónica , Insuficiencia Renal , Tumor de Wilms , Masculino , Humanos , Niño , Síndrome de Denys-Drash/complicaciones , Síndrome de Denys-Drash/genética , Síndrome de Denys-Drash/cirugía , Trasplante de Riñón/efectos adversos , Tumor de Wilms/complicaciones , Tumor de Wilms/cirugía , Tumor de Wilms/genética , Genes del Tumor de Wilms , Insuficiencia Renal/genética , Nefrectomía/efectos adversos , Neoplasias Renales/complicaciones , Neoplasias Renales/cirugía , Neoplasias Renales/genética , Insuficiencia Renal Crónica/genética , Proteinuria/genética , Proteínas WT1/genética
3.
Biosci Biotechnol Biochem ; 88(9): 999-1006, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-38886126

RESUMEN

Dinophysistoxin 1 (DTX1, 1) and okadaic acid (OA, 2), produced by the dinoflagellates Dinophysis spp. and Prorocentrum spp., are primary diarrhetic shellfish toxins (DSTs), which may cause gastric illness in people consuming such as bivalves. Both compounds convert to dinophysistoxin 3 (DTX3, 3; generic name for 1 and 2 with fatty acids conjugated at 7-OH) in bivalves. The enzyme okadaic acid O-acyl transferase (OOAT) is a membrane protein found in the microsomes of the digestive glands of bivalves. In this study, we established an in vitro enzymatic conversion reaction using 4-nitro-2,1,3-benzoxadiazole (NBD)-OA (4), an OA derivative conjugated with (R)-(-)-4-nitro-7-(3-aminopyrrolidin-1-yl)-2,1,3-benzoxadiazole (NBD-APy) on 1-CO2H, as a substrate. We detected the enzymatically produced 3, NBD-7-O-palmitoyl-OA (NBD-Pal-OA), using high-performance liquid chromatography-fluorescence detection. We believe that an OOAT assay using 4 will facilitate the fractionation and isolation of OOAT in the future.


Asunto(s)
Aciltransferasas , Ácido Ocadaico , Cromatografía Líquida de Alta Presión/métodos , Aciltransferasas/metabolismo , Aciltransferasas/química , Animales , Oxadiazoles/química , Pruebas de Enzimas/métodos
4.
Haematologica ; 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37881854

RESUMEN

Non-tuberculous mycobacterial infection (NTM) is rare in healthy children, with lymphadenitis being the most common presentation. Immunocompromised populations are known to be at high risk, but the clinical picture of NTM infection in pediatric hematology/oncology patients is unclear. In this nationwide retrospective analysis of patients under the age of 40 treated in Japanese pediatric hematology/oncology departments who developed NTM infection between January 2010 and December 2020, 36 patients (21 patients with hematopoietic stem cell transplantation (HSCT) and 15 nontransplant patients) were identified. Post-transplant patients were infected with NTM at 24 sites, including the lungs (n = 12), skin and soft tissues (n = 6), bloodstream (n = 4), and others (n = 2). Nine of twelve patients with pulmonary NTM infection had a history of pulmonary graft-versus-host disease (GVHD), and rapid-growing mycobacteria (RGM) were isolated from five of them. In nontransplant patients, the primary diseases were acute lymphoblastic leukemia (ALL; n = 5), inborn errors of immunity (IEI; n = 6), and others (n = 4). All cases of ALL had bloodstream infections with RGM, whereas all cases of IEI were infected with slow-growing mycobacteria (SGM). In summary, three typical clinical scenarios for pediatric hematology/oncology patients have been established: RGM-induced pulmonary disease in patients with pulmonary GVHD, RGM bloodstream infection in patients with ALL, and SGM infection in patients with IEI. Our findings suggest that NTM must be regarded as a pathogen for infections in these high-risk patients, especially those with pulmonary GVHD, who may require active screening for NTM.

5.
Chem Res Toxicol ; 35(11): 1950-1961, 2022 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-36315108

RESUMEN

Voltage-gated sodium channels (Nav) are closely associated with epilepsy, cardiac and skeletal muscle diseases, and neuropathic pain. Several toxic compounds have been isolated from the marine sponge Halichondria okadai; however, toxic substances that modulate Nav are yet to be identified. This study aimed to identify Nav inhibitors from two snake venoms and H. okadai using mouse neuroblastoma Neuro-2A cells (N2A), which primarily express the specific Nav subtype Nav1.7, using whole-cell patch-clamp recordings. We successfully isolated arachidonic acid (AA, 1) from the hexane extract of H. okadai, and then the fatty acid-mediated modulation of Nav in N2A was investigated in detail for the first time. Octanoic acid (2), palmitic acid (3), and oleic acid (4) showed no inhibitory activity at 100 µM, whereas AA (1), dihomo-γ-linolenic acid (DGLA, 5), and eicosapentaenoic acid (EPA, 6) showed IC50 values of 6.1 ± 2.0, 58 ± 19, and 25 ± 4.0 µM, respectively (N = 4, mean ± SEM). Structure and activity relationships were investigated for the first time using two ω-3 polyunsaturated fatty acids (PUFAs), EPA (6) and eicosatetraenoic acid (ETA, 7), and two ω-6 PUFAs, AA (1) and DGLA (5), to determine their effects on a resting state, activated state, and inactivated state. Steady-state analysis showed that the half inactivation potential was largely hyperpolarized by 10 µM AA (1), while 50 µM DGLA (5), 50 µM EPA (6), and 10 µM ETA (7) led to a slight change. The percentages of the resting state block were 24 ± 1, 22 ± 1, 34 ± 4, and 38 ± 9% in the presence of AA (1), DGLA (5), EPA (6), and ETA (7), respectively, with EPA (6) and ETA (7) exhibiting a greater inhibition than both AA (1) and DGLA (5), and their inhibitions did not increase in the following depolarization pulses. None of the compounds exhibited the use-dependent block. The half recovery times from the inactivated state for the control, AA (1), DGLA (5), EPA (6), and ETA (7) were 7.67 ± 0.33, 34.3 ± 1.10, 15.5 ± 1.10, 10.7 ± 0.31, and 3.59 ± 0.18 ms, respectively, with AA (1) exhibiting a distinctively large effect. Overall, distributed binding to the resting and the inactivated states of Nav would be significant for the inhibition of Nav, which presumably depends on the active structure of each PUFA.


Asunto(s)
Neuroblastoma , Poríferos , Canales de Sodio Activados por Voltaje , Animales , Ratones , Ácido Araquidónico/farmacología , Ácidos Araquidónicos , Neuroblastoma/tratamiento farmacológico
6.
J Nat Prod ; 85(9): 2199-2206, 2022 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-35994072

RESUMEN

Tetrodotoxin (TTX, 1) is a potent voltage-gated sodium channel blocker detected in certain marine and terrestrial organisms. We report here a new TTX analogue, 9-epiTTX (2), and a TTX-related compound, Tb-242B (4), isolated from the pufferfish Takifugu flavipterus and Dichotomyctere ocellatus, respectively. NMR analysis suggested that 2 exists as a mixture of hemilactal and 10,8-lactone forms, whereas other reported TTX analogues are commonly present as an equilibrium mixture of hemilactal and 10,7-lactone forms. Compound 2 and TTX were confirmed not to convert to each other by incubation under neutral and acidic conditions at 37 °C for 24 h. Compound 4 was identified as the 9-epimer of Tb-242A (3), previously reported as a possible biosynthetic precursor of TTX. Compound 4 was partially converted to 3 by incubation in a neutral buffer at 37 °C for 7 days, whereas 3 was not converted to 4 under this condition. Compound 2 was detected in several TTX-containing marine animals and a newt. Mice injected with 600 ng of 2 by intraperitoneal injection did not show any adverse symptoms, suggesting that the C-9 configuration in TTX is critical for its biological activity. Based on the structures, 2 and 4 were predicted to be shunt products for TTX biosynthesis.


Asunto(s)
Takifugu , Tetraodontiformes , Tetrodotoxina , Bloqueadores del Canal de Sodio Activado por Voltaje , Animales , Lactonas/química , Lactonas/aislamiento & purificación , Ratones , Tetrodotoxina/química , Tetrodotoxina/aislamiento & purificación , Tetrodotoxina/farmacología , Bloqueadores del Canal de Sodio Activado por Voltaje/química , Bloqueadores del Canal de Sodio Activado por Voltaje/aislamiento & purificación , Bloqueadores del Canal de Sodio Activado por Voltaje/farmacología
7.
BMC Ophthalmol ; 22(1): 160, 2022 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-35392846

RESUMEN

BACKGROUND: Chronic myeloid leukemia (CML) is known to cause leukemic retinopathy due to leukemia cell invasion into the choroid; however, details of the circulatory dynamics and morphological changes in the choroid are unknown. The aim of this study was to present a case of leukemic retinopathy and examine choroidal circulatory and structural analyses using laser speckle flowgraphy (LSFG) and optical coherence tomography with a binarization method, respectively. CASE PRESENTATION: A 15-year-old male diagnosed with CML complained of blurred vision in his right eye. He was ophthalmologically diagnosed with leukemic retinopathy due to retinal hemorrhage in both eyes. Tyrosine kinase inhibitors achieved complete cytogenetic remission and resolution of retinal hemorrhages at 6 months after treatment. After the treatment, the best-corrected visual acuity had recovered from 0.1 to 1.2 oculus dexter (OD) and remained at 1.5 oculus sinister (OS). The rate of change in macular blood flow assessed by the mean blur rate on LSFG was 18.3% increase OD and 25.2% decrease OS 19 months after treatment. The central choroidal thickness showed 0.4 and 3.1% reductions OD and OS, respectively. The binarization technique demonstrated that the rate of luminal areas in choroidal areas exhibited 3.2% increase OD but 4.8% decrease OS. CONCLUSION: Choroidal blood flow improved OD after treatment for CML, while it deteriorated OS, together with choroidal thinning due to reduction of luminal areas. The degrees of leukemia cell invasion into the choroidal tissue and tissue destruction might be different between the eyes in this case.


Asunto(s)
Leucemia Mielógena Crónica BCR-ABL Positiva , Enfermedades de la Retina , Adolescente , Coroides/irrigación sanguínea , Angiografía con Fluoresceína , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/complicaciones , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Masculino , Enfermedades de la Retina/diagnóstico , Tomografía de Coherencia Óptica/métodos
8.
Mar Drugs ; 20(3)2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-35323466

RESUMEN

Saxitoxin and its analogues, paralytic shellfish toxins (PSTs), are potent and specific voltage-gated sodium channel blockers. These toxins are produced by some species of freshwater cyanobacteria and marine dinoflagellates. We previously identified several biosynthetic intermediates of PSTs, as well as new analogues, from such organisms and proposed the biosynthetic and metabolic pathways of PSTs. In this study, 12ß-deoxygonyautoxin 5 (12α-gonyautoxinol 5 = gonyautoxin 5-12(R)-ol) was identified in the freshwater cyanobacterium, Dolichospermum circinale (TA04), and 12ß-deoxysaxitoxin (12α-saxitoxinol = saxitoxin-12(R)-ol) was identified in the same cyanobacterium and in the marine dinoflagellate Alexandrium pacificum (Group IV) (120518KureAC) for the first time from natural sources. The authentic standards of these compounds and 12α-deoxygonyautoxin 5 (12ß-gonyautoxinol 5 = gonyautoxin 5-12(S)-ol) were prepared by chemical derivatization from the major PSTs, C1/C2, produced in D. circinale (TA04). These standards were used to identify the deoxy analogues by comparing the retention times and MS/MS spectra using high-resolution LC-MS/MS. Biosynthetic or metabolic pathways for these analogues have also been proposed based on their structures. The identification of these compounds supports the α-oriented stereoselective oxidation at C12 in the biosynthetic pathway towards PSTs.


Asunto(s)
Cianobacterias/química , Dinoflagelados/química , Saxitoxina/análogos & derivados , Cianobacterias/metabolismo , Dinoflagelados/metabolismo , Estructura Molecular , Saxitoxina/química , Saxitoxina/aislamiento & purificación , Saxitoxina/metabolismo
9.
Oncology ; 99(1): 23-31, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32906115

RESUMEN

OBJECTIVE: Most types of intracranial germ cell tumors (IGCTs) are sensitive to chemoradiation. However, biopsy specimens are usually small and thus cannot be used for obtaining an accurate pathological diagnosis. Recently, the cerebrospinal fluid (CSF) placental alkaline phosphatase (PLAP) value has been considered a new biomarker of IGCTs. The present study aimed to evaluate the discriminatory characteristics of the CSF-PLAP value upon diagnosis and at the time of recurrence in patients with IGCTs. METHODS: Between 2015 and 2019, this study included 37 patients with tumors located in the intraventricular and/or periventricular region. The CSF-PLAP level was assessed before the patients received any treatment. The PLAP level was evaluated during and after first-line chemoradiotherapy in 7 patients with IGCTs. The CSF-PLAP values were compared according to histological diagnosis, and the correlation between these values and radiographical features was assessed. The CSF-PLAP values of 6 patients with IGCTs with suspected recurrence were evaluated based on neuroimaging findings. RESULTS: The CSF-PLAP values were significantly higher in patients with IGCTs than in those with other types of brain tumor (n = 19 vs. 18; median: 359.0 vs. <8.0 pg/mL). The specificity and sensitivity were 88 and 95%, respectively, with a cutoff value of 8.0 pg/mL. In patients with IGCT, the CSF-PLAP value was higher in patients with germinoma than in those with nongerminomatous germ cell tumors (n = 12 vs. 7; median: 415.0 vs. 359.0 pg/mL). Regarding the time course, the CSF-PLAP value decreased to below the detection limit after the reception of first-line chemoradiotherapy in all 7 patients. A significant correlation was observed between the initial CSF-PLAP value and the tumor reduction volume after receiving first-line chemoradiotherapy (p < 0.0003, R2 = 0.6165, logY = 1.202logX - 1.727). Among the patients with suspected IGCT recurrence (n = 6), the CSF-PLAP value was high in patients with recurrence (n = 3; median: 259.0 pg/mL), and that in patients (n = 3) without recurrence was below the lower detection limit. CONCLUSIONS: The CSF-PLAP level is a useful biomarker during the initial diagnosis of IGCTs and at the time of recurrence. It may be associated with the volume of germinomatous components of tumors.


Asunto(s)
Fosfatasa Alcalina/líquido cefalorraquídeo , Biomarcadores de Tumor/líquido cefalorraquídeo , Neoplasias Encefálicas/líquido cefalorraquídeo , Isoenzimas/líquido cefalorraquídeo , Neoplasias de Células Germinales y Embrionarias/líquido cefalorraquídeo , Adolescente , Adulto , Neoplasias Encefálicas/enzimología , Neoplasias Encefálicas/patología , Niño , Preescolar , Proteínas Ligadas a GPI/líquido cefalorraquídeo , Germinoma/líquido cefalorraquídeo , Germinoma/patología , Humanos , Masculino , Recurrencia Local de Neoplasia/líquido cefalorraquídeo , Recurrencia Local de Neoplasia/patología , Neoplasias de Células Germinales y Embrionarias/enzimología , Neoplasias de Células Germinales y Embrionarias/patología , Adulto Joven
10.
Org Biomol Chem ; 19(36): 7894-7902, 2021 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-34549233

RESUMEN

Domoic acid (1, DA), a member of the natural kainoid family, is a potent agonist of ionotropic glutamate receptors in the central nervous system. The chemical synthesis of DA and its derivatives requires considerable effort to establish a pyrrolidine ring containing three contiguous stereocenters. Recently, a biosynthetic cyclase for DA, DabC, was identified. This enzyme cyclizes the linear precursor of isodomoic acid A (IA) to IA, a bioactive DA analogue. In this study, we developed a bioconversion system to obtain DA analogues from linear substrates prepared by simple chemical synthesis using DabC expressed in Escherichia coli, in vivo. Three IA analogues with various substitutions at the C7'-geranyl terminus were prepared using this system: two minor natural analogues, 7'-methyl-IA (5) and 7'-hydroxy-IA (6), and one new unnatural analogue, 7'-amide-IA (7). In addition, the toxicity of these DA analogues in mice was examined by intracerebroventricular injection. Most of the mice injected with 5 (3 nmol) and 6 (3 nmol) did not show any adverse symptoms, whereas the mice injected with 7 (3 nmol) showed typical symptoms induced by DA (1, 0.7 nmol) and IA (2, 3 nmol). These results suggest that the 7'-carbonyl group in the side chain of IA (2) is crucial for its toxicity. The docking studies of DA, IA (2), 5, 6, and 7 to GluK1 supported these results.


Asunto(s)
Ácido Kaínico/análogos & derivados
11.
Pathol Int ; 71(5): 348-354, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33713516

RESUMEN

A 5-year-old girl presented with headache and vomiting. Head computed tomography and magnetic resonance imaging showed a right frontal lobe tumor with marked calcification. The patient underwent resection surgery with suspicion of anaplastic ependymoma, and the tumor was gross totally removed. Pathological examination revealed areas of dense tumor cells with a high nucleocytoplasmic ratio and myxoid areas consisting of tumor cells with a round-shaped nucleus and eosinophilic cytoplasm. Perivascular pseudorosette, necrosis, circumscribed growth, and microcalcification were also observed. Immunohistochemistry demonstrated negative staining for glial fibrillary protein and epithelial membrane antigen. Diagnosis of a high-grade neuroepithelial tumor (HGNET) with BCL6 corepressor (BCOR) alteration was made based on pathological findings and internal tandem duplication in the exon 15 of BCOR. Although calcification on radiological and pathological examination is not typical, it would be essential to recognize that calcification could appear in HGNET-BCOR.


Asunto(s)
Neoplasias Encefálicas , Calcinosis , Neoplasias Neuroepiteliales , Proteínas Proto-Oncogénicas , Proteínas Represoras , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Preescolar , Proteínas Co-Represoras/análisis , Proteínas Co-Represoras/genética , Femenino , Duplicación de Gen , Humanos , Inmunohistoquímica , Imagen por Resonancia Magnética , Neoplasias Neuroepiteliales/genética , Neoplasias Neuroepiteliales/patología , Proteínas Proto-Oncogénicas/análisis , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-bcl-6/metabolismo , Radiología , Proteínas Represoras/análisis , Proteínas Represoras/genética
12.
Biol Blood Marrow Transplant ; 26(5): 902-910, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31790827

RESUMEN

Hematopoietic stem cell transplantation (HSCT) is the only curative treatment for juvenile myelomonocytic leukemia (JMML), but few large studies of HSCT for JMML exist. Using data from the Japan Society for Hematopoietic Cell Transplantation registry, we analyzed the outcomes of 129 children with JMML who underwent HSCT between 2000 and 2011. The 5-year overall survival (OS) rate and cumulative incidence of relapse were 64% and 34%, respectively. A regimen of busulfan/fludarabine/melphalan was the most commonly used (59 patients) and provided the best outcomes; the 5-year OS rate reached 73%, and the cumulative incidences of relapse and transplantation-related mortality were 26% and 9%, respectively. In contrast, the use of the irradiation-based myeloablative regimen was the most significant risk factor for OS (hazard ratio [HR], 2.92; P = .004) in the multivariate model. In addition, chronic graft-versus-host disease (GVHD) was strongly associated with lower relapse (HR, 0.37; P = .029) and favorable survival (HR, 0.22; P = .006). The current study has shown that a significant proportion of children with JMML can be cured with HSCT, especially those receiving the busulfan/fludarabine/melphalan regimen. Based on the lower relapse and better survival observed in patients with chronic GVHD, additional treatment strategies that focus on enhancing graft-versus-leukemia effects may further improve survival.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Leucemia Mielomonocítica Juvenil , Busulfano/uso terapéutico , Niño , Enfermedad Injerto contra Huésped/etiología , Humanos , Japón , Leucemia Mielomonocítica Juvenil/terapia , Estudios Retrospectivos , Acondicionamiento Pretrasplante , Vidarabina
13.
J Pediatr Hematol Oncol ; 42(8): e791-e794, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32049768

RESUMEN

We report an 18-year-old female individual with septic arthritis due to Mycobacterium kansasii. Three years and 6 months before arthritis, the patient underwent bone marrow transplantation and developed severe chronic graft-versus-host disease. The arthritis was refractory to medication, and she underwent joint lavage of the right foot, hip joint, and elbow joint. After surgery, her joint symptoms were relieved, and chronic graft-versus-host disease remitted more easily. It is important that we maintain a high index of suspicion for mycobacterial arthritis and diagnose it early when immunosuppressed patients experience chronic pain and joint swelling.


Asunto(s)
Artritis Infecciosa/epidemiología , Trasplante de Médula Ósea/efectos adversos , Enfermedad Injerto contra Huésped/etiología , Infecciones por Mycobacterium no Tuberculosas/complicaciones , Mycobacterium kansasii/patogenicidad , Leucemia-Linfoma Linfoblástico de Células T Precursoras/terapia , Adolescente , Antibacterianos/uso terapéutico , Artritis Infecciosa/tratamiento farmacológico , Artritis Infecciosa/microbiología , Femenino , Enfermedad Injerto contra Huésped/patología , Humanos , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Infecciones por Mycobacterium no Tuberculosas/microbiología , Mycobacterium kansasii/efectos de los fármacos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patología , Pronóstico
15.
Pediatr Blood Cancer ; 66(12): e27977, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31489974

RESUMEN

BACKGROUND: Corticosteroids, especially dexamethasone, play a critical role in chemotherapy for pediatric hematological malignancies. We previously observed that patients with complaints of headache or photophobia during corticosteroid administration had high intraocular pressure (IOP). PROCEDURE: We measured IOP during corticosteroid administration in 15 patients with acute leukemia or lymphoma undergoing treatment at our institution from January 2016 to December 2018. IOP was measured by an ophthalmologist within seven days of the initiation of standard dose of corticosteroid, which was defined as 60 mg/m2 /day for prednisolone and 10 mg/m2 /day for dexamethasone. RESULTS: Fifteen patients received 52 courses of chemotherapy containing corticosteroids. IOP exceeded 21 mmHg among 13 patients in 28 courses. Twelve of the 13 patients were administered topical treatment, and six of the 12 patients needed additional diuretic agents. IOP during the chemotherapy courses containing dexamethasone was significantly higher compared with IOP during the chemotherapy courses containing prednisolone. Only two patients complained of symptoms, such as headache and photophobia, and one of the two patients underwent trabeculotomy. Funduscopic findings were normal in all patients. There was a dose-associated decrease in IOP with reduction of dexamethasone dose. CONCLUSIONS: IOP should be measured during administration of substantial corticosteroid doses even in patients with no symptoms. Further investigations regarding the level of IOP for intervention need to be conducted.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Glaucoma/inducido químicamente , Neoplasias Hematológicas/tratamiento farmacológico , Presión Intraocular/efectos de los fármacos , Agudeza Visual/efectos de los fármacos , Adolescente , Corticoesteroides/administración & dosificación , Niño , Preescolar , Dexametasona/administración & dosificación , Femenino , Estudios de Seguimiento , Glaucoma/epidemiología , Neoplasias Hematológicas/patología , Humanos , Masculino , Prednisolona/administración & dosificación , Pronóstico , Estudios Retrospectivos
16.
J Nat Prod ; 82(6): 1627-1633, 2019 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-31117523

RESUMEN

Four kainic acid (KA, 1)-related compounds, 4-hydroxykainic acid (2), allo-4-hydroxykainic acid (3), N-dimethylallyl-l-glutamic acid (4), and N-dimethylallyl- threo-3-hydroxyglutamic acid (5), were isolated from the red alga Digenea simplex. The structures of these compounds were elucidated using spectroscopic methods. Compounds 2 and 3 are possible oxidative metabolites of KA and allo-KA (6), respectively. Compound 4 was recently reported as the biosynthetic precursor of KA, but the absolute configuration of 4 has not been previously determined. Herein, we determined the absolute configuration of 4 as 2( S) using advanced Marfey's method. Compound 5 is similar to N-geranyl-3( R)-hydroxy-l-glutamic acid (8), which was previously identified in a domoic acid (DA)-containing red alga. Compounds 5 and 8 are predicted to be biosynthetic byproducts of the radical-mediated cyclization reaction to form the pyrrolidine rings of KA and DA, respectively. Furthermore, the toxicities of 1-5 in mice were examined by intracerebroventricular injection. The toxicity of 2 was less than that of KA; however, the mice injected with 2 showed symptoms similar to those induced by KA, while 3-5 did not induce typical symptoms of KA in mice.


Asunto(s)
Glutamatos/química , Ácido Glutámico/química , Ácido Kaínico/análogos & derivados , Ácido Kaínico/metabolismo , Pirrolidinas/química , Rhodophyta/química , Animales , Vías Biosintéticas , Ácido Kaínico/química , Ácido Kaínico/toxicidad , Ratones , Estructura Molecular
17.
Mar Drugs ; 17(12)2019 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-31766477

RESUMEN

Paralytic shellfish toxins (PSTs) are the major neurotoxic contaminants of edible bivalves in Japan. Tetrodotoxin (TTX) was recently detected in bivalve shellfish around the world, drawing widespread attention. In Japan, high levels of TTX were reported in the digestive gland of the scallop, Patinopecten yessoensis, in 1993; however, no new data have emerged since then. In this study, we simultaneously analyzed PSTs and TTX in scallops cultured in a bay of east Japan using hydrophilic interaction chromatography (HILIC)-MS/MS. These scallops were temporally collected from April to December 2017. The highest concentration of PSTs (182 µmol/kg, total congeners) in the hepatopancreas was detected in samples collected on May 23, lined to the cell density of the dinoflagellate, Alexandrium tamarense, in seawater around the scallops, whereas the highest concentration of TTX (421 nmol/kg) was detected in samples collected on August 22. Contrary to the previous report, temporal variation of the PSTs and TTX concentrations did not coincide. The highest concentration of TTX in the entire edible tissues was 7.3 µg/kg (23 nmol/kg) in samples obtained on August 22, which was lower than the European Food Safety Authority (EFSA)-proposed threshold, 44 µg TTX equivalents/kg shellfish meat. In addition, 12ß-deoxygonyautoxin 3 was firstly identified in scallops.


Asunto(s)
Dinoflagelados/química , Pectinidae/química , Saxitoxina/análogos & derivados , Alimentos Marinos/análisis , Tetrodotoxina/análisis , Animales , Acuicultura , Bahías , Cromatografía Líquida de Alta Presión , Japón , Saxitoxina/análisis , Saxitoxina/toxicidad , Estaciones del Año , Agua de Mar/microbiología , Intoxicación por Mariscos/etiología , Intoxicación por Mariscos/prevención & control , Espectrometría de Masas en Tándem , Tetrodotoxina/toxicidad , Factores de Tiempo
18.
Pediatr Int ; 61(3): 230-234, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30570800

RESUMEN

BACKGROUND: Central venous (CV) catheters are required for chemotherapy but they may become a source of life-threatening infections of the bloodstream. The most effective way to disinfect the port of a CV catheter has not been established. METHODS: We report the data obtained between April 2008 and March 2010 using 83% ethanol (period I) and between April 2010 and March 2014 using 10% povidone-iodine (period II) to sterilize the access port. The participants received chemotherapy or autologous/allogeneic stem cell transplantation at the present institution. RESULTS: No significant difference was observed in patient characteristics between the two periods, such as disease, median age, or the period of neutropenia. The incidence of positive blood culture during periods I and II was 18.5% (31/168) and 11.4% (40/350; P = 0.041), respectively. The incidence of catheter-associated bloodstream infection on blood culture during periods I and II was 11.9% (20/168) and 6.3% (22/350; P = 0.043), respectively. Bacillus cereus infection was not detected during period II. CONCLUSION: The incidence of infection caused by CV catheters was significantly reduced using povidone-iodine; therefore, we recommend this procedure as part of the routine in chemotherapy.


Asunto(s)
Antiinfecciosos Locales/administración & dosificación , Bacteriemia/epidemiología , Infecciones Relacionadas con Catéteres/prevención & control , Cateterismo Venoso Central/efectos adversos , Povidona Yodada/administración & dosificación , Adolescente , Adulto , Bacteriemia/etiología , Bacteriemia/prevención & control , Cultivo de Sangre/métodos , Infecciones Relacionadas con Catéteres/epidemiología , Infecciones Relacionadas con Catéteres/microbiología , Niño , Preescolar , Etanol/administración & dosificación , Neutropenia Febril , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Esterilización/métodos , Adulto Joven
19.
Pediatr Int ; 61(11): 1103-1108, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31519067

RESUMEN

BACKGROUND: Ploidy is a highly significant prognostic factor for pediatric acute lymphoblastic leukemia (ALL). Children with hypodiploid ALL have poor outcomes despite current intensive chemotherapy. Little has been investigated with regard to hypodiploid ALL in Japanese children. METHODS: We retrospectively collected clinical data on hypodiploid ALL cases from the registries of prospective multicenter trials conducted by the four independent clinical study groups in Japan between 1997 and 2012. RESULTS: A total of 117 ALL patients with hypodiploidy were analyzed in this study. There were 101, eight, and eight patients with 45, 44, and fewer than 44 chromosomes, respectively. The 5 year overall survival rates differed significantly: 86.0%, 87.5%, and 62.5% for patients with 45, 44, and fewer than 44 chromosomes, respectively (P = 0.037). Of the eight patients with 44 chromosomes, seven were alive, including five patients who maintained complete remission without undergoing hematopoietic stem cell transplantation (HSCT). Of the eight patients with fewer than 44 chromosomes, six were good responders to prednisolone and none had induction failure, but the relapse rate was high (5/8). No patients had central nervous system relapse. Four patients underwent HSCT after relapse, but only one survived. CONCLUSIONS: Outcomes of Japanese ALL patients with fewer than 44 chromosomes were poor, as previously reported in other countries. Although the sample size was small, patients with 44 chromosomes had better prognoses than those previously reported. Further studies including international collaboration are needed to improve outcomes for pediatric ALL patients with fewer than 44 chromosomes.


Asunto(s)
Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiología , Sistema de Registros , Encuestas y Cuestionarios , Adolescente , Niño , Preescolar , Terapia Combinada , Femenino , Trasplante de Células Madre Hematopoyéticas , Humanos , Incidencia , Lactante , Japón/epidemiología , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Pronóstico , Estudios Prospectivos , Inducción de Remisión/métodos , Tasa de Supervivencia/tendencias
20.
Chemistry ; 24(28): 7250-7258, 2018 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-29504641

RESUMEN

Tetrodotoxin (TTX, 1) is a potent neurotoxin that is widely found in both terrestrial and marine animals; however, the biosynthetic pathway and genes for TTX have not yet been elucidated. Previously, we proposed that TTX originated from a monoterpene; this hypothesis was based on the structures of cyclic guanidino compounds that are commonly found in toxic newts. However, these compounds have not been detected in marine organisms. Instead, a series of deoxy analogues of TTX were found in toxic marine animals; thus, we further screened for TTX-related compounds in marine animals. Herein, we report seven novel spiro bicyclic guanidino compounds 2-8 that were isolated from the pufferfish Tetraodon biocellatus. In compounds 2-5 and 7-8, a six-membered cyclic guanidino amide is spiro-fused with 2,4-dimethyl cyclohexane, whereas in compound 6, the same cyclic guanidino amide is spiro-fused with 2,3,5-trimethylcyclopentane. Compounds 2-5 and 7-8 have the same carbon skeleton and relative configuration as TTX. Thus, we proposed that compounds 2-8 are biosynthetic intermediates of TTX in marine environments. TTX could be biosynthetically derived from compound 7 via intermediates 2-5 through several oxidations, amide hydrolysis, and formation of the hemiaminal and lactone found in 5,6,11-trideoxyTTX, the major TTX analogue, whereas compounds 6 and 8 might be shunt products. LC-MS analysis confirmed the wide distribution of compounds 2, 3, or both in TTX-containing marine animals, namely pufferfish, crab, octopus, and flatworm, but compounds 2-8 were not detected in newts.


Asunto(s)
Guanidinas/química , Compuestos de Espiro/química , Tetrodotoxina/química , Animales , Carbono , Cromatografía Liquida , Oxidación-Reducción , Espectrometría de Masas en Tándem , Tetraodontiformes
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