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1.
Neuro Oncol ; 26(2): 236-250, 2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-37847405

RESUMO

BACKGROUND: Glioblastoma (GBM) has poor prognosis due to ineffective agents and poor delivery methods. MicroRNAs (miRs) have been explored as novel therapeutics for GBM, but the optimal miRs and the ideal delivery strategy remain unresolved. In this study, we sought to identify the most effective pan-subtype anti-GBM miRs and to develop an improved delivery system for these miRs. METHODS: We conducted an unbiased screen of over 600 miRs against 7 glioma stem cell (GSC) lines representing all GBM subtypes to identify a set of pan-subtype-specific anti-GBM miRs and then used available TCGA GBM patient outcomes and miR expression data to hone in on miRs that were most likely to be clinically effective. To enhance delivery and expression of the miRs, we generated a polycistronic plasmid encoding 3 miRs (pPolymiR) and used HEK293T cells as biofactories to package pPolymiR into engineered exosomes (eExos) that incorporate viral proteins (Gag/VSVg) in their structure (eExos+pPolymiR) to enhance function. RESULTS: Our stepwise screen identified miR-124-2, miR-135a-2, and let-7i as the most effective miRs across all GBM subtypes with clinical relevance. Delivery of eExos+pPolymiR resulted in high expression of all 3 miRs in GSCs, and significantly decreased GSC proliferation in vitro. eExos+pPolymiR prolonged survival of GSC-bearing mice in vivo when compared with eExos carrying each of the miRs individually or as a cocktail. CONCLUSION: eExos+pPolymiR, which includes a pan-subtype anti-glioma-specific miR combination encoded in a polycistronic plasmid and a novel exosome delivery platform, represents a new and potentially powerful anti-GBM therapeutic.


Assuntos
Neoplasias Encefálicas , Exossomos , Glioblastoma , Glioma , MicroRNAs , Humanos , Animais , Camundongos , MicroRNAs/genética , Glioblastoma/genética , Glioblastoma/terapia , Glioblastoma/metabolismo , Exossomos/genética , Exossomos/metabolismo , Células HEK293 , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Glioma/genética , Regulação Neoplásica da Expressão Gênica
3.
Surg Neurol Int ; 14: 228, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37404491

RESUMO

Background: Cerebrospinal fluid (CSF) rhinorrhea with meningoencephalocele (MEC) associated with Sternberg's canal is rare. We treated two such cases. Case Description: A 41-year-old man and a 35-year-old woman presented with CSF rhinorrhea and mild headache worsening with standing posture. Head computed tomography showed a defect close to the foramen rotundum in the lateral wall of the left sphenoid sinus in both cases. Head magnetic resonance (MR) imaging and MR cisternography revealed that brain parenchyma had herniated into the lateral sphenoid sinus through the defect of the middle cranial fossa. The intradural and extradural spaces and bone defect were sealed with fascia and fat through both intradural and extradural approaches. The MEC was cut away to prevent infection. CSF rhinorrhea completely stopped after the surgery. Conclusion: Our cases were characterized by empty sella, thinning of the dorsum sellae, and large arteriovenous malformations that suggest chronic intracranial hypertension. The possibility of Sternberg's canal in patients with CSF rhinorrhea with chronic intracranial hypertension should be considered. The cranial approach has the advantages of lower infection risk and the ability to close the defect with multilayer plasty under direct vision. The transcranial approach is still safe if performed by a skillful neurosurgeon.

4.
NPJ Microgravity ; 9(1): 33, 2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37120425

RESUMO

We conducted a charge-charge clustering experiment of positively and negatively charged colloidal particles in aqueous media under a microgravity environment at the International Space Station. A special setup was used to mix the colloid particles in microgravity and then these structures were immobilized in gel cured using ultraviolet (UV) light. The samples returned to the ground were observed by optical microscopy. The space sample of polystyrene particles with a specific gravity ρ (=1.05) close to the medium had an average association number of ~50% larger than the ground control and better structural symmetry. The effect of electrostatic interactions on the clustering was also confirmed for titania particles (ρ ~ 3), whose association structures were only possible in the microgravity environment without any sedimentation they generally suffer on the ground. This study suggests that even slight sedimentation and convection on the ground significantly affect the structure formation of colloids. Knowledge from this study will help us to develop a model which will be used to design photonic materials and better drugs.

5.
Science ; 371(6526): 260-264, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33446551

RESUMO

The surface of neutron-rich heavy nuclei, with a neutron skin created by excess neutrons, provides an important terrestrial model system to study dilute neutron-rich matter. By using quasi-free α cluster-knockout reactions, we obtained direct experimental evidence for the formation of α clusters at the surface of neutron-rich tin isotopes. The observed monotonous decrease of the reaction cross sections with increasing mass number, in excellent agreement with the theoretical prediction, implies a tight interplay between α-cluster formation and the neutron skin. This result, in turn, calls for a revision of the correlation between the neutron-skin thickness and the density dependence of the symmetry energy, which is essential for understanding neutron stars. Our result also provides a natural explanation for the origin of α particles in α decay.

6.
Biologicals ; 58: 73-75, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30660437

RESUMO

A simple method for the determination of low levels of residual formaldehyde in an inactivated Zika vaccine formulated with aluminum hydroxide gel was developed for the assessment of drug product quality. Formaldehyde was reacted with 2,4-dinitrophenylhydrazine (DNPH) and the derivatized product was detected by HPLC with an UV detector at 360 nm. The derivatization reaction could be carried out in a 2-mL HPLC vial and the sample was analyzed directly. The method was fully validated according to the International Conference on Harmonization Q2 guidelines. Aluminum hydroxide gel up to 1.0 mg/mL (aluminum concentration) did not interfere with the determination of formaldehyde in drug product. Formaldehyde concentrations of 0.05 µg/mL (quantitation limit) to 1.00 µg/mL in the Zika vaccine could be precisely determined. Hence, this method proved to be suitable for quality control of the Zika vaccine.


Assuntos
Adjuvantes Imunológicos/química , Hidróxido de Alumínio/química , Formaldeído/análise , Vacinas Virais/química , Zika virus , Humanos
7.
Cancer Genomics Proteomics ; 15(4): 343-348, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29976640

RESUMO

BACKGROUND: Fusion genes driving tumourigenesis have drawn the attention of researchers and oncologists. Despite the importance of such molecular alterations, there are no comprehensive reproducible methods for detecting fusion genes. MATERIALS AND METHODS: Nineteen paediatric brain tumours of five types, namely pilocytic astrocytoma, oligodendroglioma, anaplastic astrocytoma, glioblastoma and, ganglioglioma, were examined to detect fusion genes using a pyrosequencing-based method following RNA isolation, cDNA synthesis and real-time polymerase chain reaction. RESULTS: Our method successfully detected KIAA1549-v-raf murine sarcoma viral oncogene homolog B1 (BRAF) fusion in 14 out of 19 patients suffering from five types of paediatric brain tumours providing information on fusion breakpoints within 2 h. CONCLUSION: A comprehensive method for detecting fusion genes in paediatric brain tumours was evaluated. This method identified KIAA1549-BRAF fusion variants quickly. Our results may help researchers interested in the role of fusion genes in tumourigenesis.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Proteínas de Fusão Oncogênica/genética , Análise de Sequência de DNA/métodos , Adolescente , Biomarcadores Tumorais/genética , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino
8.
Surg Neurol Int ; 9: 69, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29721348

RESUMO

BACKGROUND: Hemangiopericytomas are a rare entity commonly presenting as subdural tumors. CASE DESCRIPTION: A 57-year-old man presented with a progressive visual disturbance over a period of 3 weeks. Cranial computed tomography scans revealed an isodense mass at the tip of the left middle fossa, extending into the orbital apex, and accompanying bony erosions in the sphenoid ridge. On magnetic resonance imaging, the lesion appeared isointense both on T1- and T2-weighted sequences, and intensely enhanced on contrast examinations. A frontotemporal craniotomy revealed a dura-based, capsulized tumor located entirely in the epidural space. A gross total resection was achieved for the tumor and histologically verified as hemangiopericytoma. CONCLUSION: Hemangiopericytoma should be assumed in a differential diagnosis when encountering epidural tumors, and total resection should be attempted when possible.

9.
J Alzheimers Dis ; 63(3): 989-1002, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29710721

RESUMO

BACKGROUND: Alzheimer's disease (AD) pathology in idiopathic normal pressure hydrocephalus (iNPH) contributes to poor shunt responses. Amyloid-ß 1- 42 (Aß42) toxic conformer was recently identified with features of rapid oligomerization, strong neurotoxicity and synaptotoxicity. OBJECTIVE: This observational study points to Aß42 toxic conformer as a biomarker for AD pathology and for poor postoperative prognosis in patients with iNPH. METHODS: The first cohort consisted of patients with AD (n = 17) and iNPH (n = 17), and cognitively normal individuals (CN, n = 12). The second cohort, consisted of 51 patients with iNPH, was divided into two groups according to phosphorylated Tau (pTau) level (low- and high-pTau groups); the low-pTau group was further subdivided according to one-year postoperative change in Aß42 toxic conformer ratio (%) [Aß42 toxic conformer/Aß42×100] (decreased- and increased-conformer subgroups). Enzyme-linked immunosorbent assay was used to measure pTau, Aß42, and Aß42 toxic conformer in cerebrospinal fluid. Outcomes were evaluated using neuropsychological tests one- and two-years postoperatively. RESULTS: In the first cohort, Aß42 toxic conformer ratio in the iNPH group (10.8%) was significantly higher than that in the CN group (6.3%) and significantly lower than that in the AD group (17.2%). In the second cohort, the high-pTau group showed cognitive decline two-years postoperatively compared to baseline. However, the low-pTau group showed favorable outcomes one-year postoperatively; furthermore, the increased-conformer subgroup showed cognitive decline two-years postoperatively while the decreased-conformer subgroup maintained the improvement. CONCLUSIONS: Change in Aß42 toxic conformer ratio predicts long-term cognitive outcome in iNPH, even in the low-pTau group.


Assuntos
Doença de Alzheimer/complicações , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Transtornos Cognitivos/líquido cefalorraquidiano , Transtornos Cognitivos/etiologia , Hidrocefalia de Pressão Normal/complicações , Fragmentos de Peptídeos/líquido cefalorraquidiano , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Estatísticas não Paramétricas , Substância Branca/patologia , Proteínas tau/líquido cefalorraquidiano
10.
Radiol Case Rep ; 13(3): 693-696, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29682141

RESUMO

A 26-year-old woman with familial neurofibromatosis type 1 sustained headache that worsened for 1 month. Neuroimaging revealed a mild ventriculomegaly and nonenhancing lesion in the pons. In spite of repeated cerebrospinal fluid examinations and magnetic resonance imaging, the etiology was not determined. The affected pons markedly enlarged in the following 2 months, with extensive leptomeningeal dissemination. Biopsy through hemilaminectomy of the T9 was diagnosed as glioblastoma multiforme. Prompt histologic examination should be performed when patients with familial neurofibromatosis type 1 manifest communicating hydrocephalus coexistent with a nonenhancing tumor.

11.
PLoS One ; 11(9): e0162538, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27611433

RESUMO

BACKGROUND: Chest auscultation is commonly performed during respiratory physical therapy (RPT). However, the changes in breath sounds in children with atelectasis have not been previously reported. The aim of this study was to clarify the characteristics of breath sounds in children with atelectasis using acoustic measurements. METHOD: The subjects of this study were 13 children with right middle lobe atelectasis (3-7 years) and 14 healthy children (3-7 years). Lung sounds at the bilateral fifth intercostal spaces on the midclavicular line were recorded. The right-to-left ratio (R/L ratio) and the expiration to inspiration ratio (E/I ratio) of the breath sound sound pressure were calculated separately for three octave bands (100-200 Hz, 200-400 Hz, and 400-800 Hz). These data were then compared between the atelectasis and control groups. In addition, the same measurements were repeated after treatment, including RPT, in the atelectasis group. RESULT: Before treatment, the inspiratory R/L ratios for all the frequency bands were significantly lower in the atelectasis group than in the control group, and the E/I ratios for all the frequency bands were significantly higher in the atelectasis group than in the control group. After treatment, the inspiratory R/L ratios of the atelectasis group did not increase significantly, but the E/I ratios decreased for all the frequency bands and became similar to those of the control group. CONCLUSION: Breath sound attenuation in the atelectatic area remained unchanged even after radiographical resolution, suggesting a continued decrease in local ventilation. On the other hand, the elevated E/I ratio for the atelectatic area was normalized after treatment. Therefore, the differences between inspiratory and expiration sound intensities may be an important marker of atelectatic improvement in children.


Assuntos
Pulmão/fisiologia , Atelectasia Pulmonar/fisiopatologia , Atelectasia Pulmonar/terapia , Sons Respiratórios/fisiologia , Auscultação/métodos , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Modalidades de Fisioterapia
12.
J Vet Med Sci ; 78(11): 1737-1740, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27498996

RESUMO

One Holstein cow housed with 21 other cows exhibited clinical signs of pyrexia, anorexia and diarrhea along with severe hemoglobinuria. Hematological and biochemical analyses conducted before and after antibiotic therapy indicated severe hemolytic anemia and disruption of hepatic function. A general improvement in conditions was observed after an 11-day program of treatment comprising a regular dose of antibiotics and prescribed supportive therapies. A tentative diagnosis of bacillary hemoglobinuria was made based on the clinical and clinico-pathologic features on day 7. A molecular diagnosis was made by a PCR amplification of the flagellin gene of Clostridium haemolyticum using DNA extracted from the whole blood. The cow was diagnosed with the first recorded occurrence of bacillary hemoglobinuria of Holstein cattle in Japan.


Assuntos
Antibacterianos/uso terapêutico , Doenças dos Bovinos/microbiologia , Infecções por Clostridium/veterinária , Clostridium/isolamento & purificação , Hemoglobinúria/veterinária , Anemia Hemolítica/microbiologia , Anemia Hemolítica/veterinária , Animais , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/urina , Infecções por Clostridium/tratamento farmacológico , Infecções por Clostridium/microbiologia , Infecções por Clostridium/urina , Feminino , Hemoglobinúria/tratamento farmacológico , Hemoglobinúria/microbiologia , Japão
13.
J Vet Med Sci ; 76(10): 1403-5, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24976585

RESUMO

The influences of glucose supplementation on early development of bovine embryos in BSA-free synthetic oviduct fluid were examined. Among the groups supplemented with 1.5, 2.0, 4.0 or 5.6 mM glucose either at 0, 72 or 144 hr after fertilization, blastocysts yield significantly increased in the group supplemented with 4.0 mM glucose 144 hr after fertilization compared to the controls without glucose supplementation. The results suggest that appropriate amounts of glucose supplemented to the medium at the specific stage of embryo culture may be useful for the production of bovine blastocysts.


Assuntos
Bovinos/embriologia , Técnicas de Cultura Embrionária/veterinária , Desenvolvimento Embrionário/efeitos dos fármacos , Fertilização in vitro/veterinária , Glucose/farmacologia , Zigoto/efeitos dos fármacos , Animais , Zigoto/crescimento & desenvolvimento
14.
Org Lett ; 16(2): 358-61, 2014 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-24364475

RESUMO

Isopropyl carbamates derived from benzylamines provide isoindolinones by treatment with phosphorus pentoxide at room temperature. Utility of this Bischler-Napieralski-type cyclization and a new mechanism involving a carbamoyl cation for rationalization of this smooth conversion are discussed.


Assuntos
Benzilaminas/química , Carbamatos/química , Indóis/síntese química , 2-Propanol/química , Ciclização , Ésteres , Indóis/química , Estrutura Molecular , Compostos de Fósforo/química , Temperatura
15.
Artigo em Inglês | MEDLINE | ID: mdl-24109915

RESUMO

The e-Textile is the key technology for continuous ambient health monitoring to increase quality of life of patients with chronic diseases. The authors introduce techniques of Japanese historical textile, NISHIJIN, which illustrate almost any pattern from one continuous yarn within the machine weaving process, which is suitable for mixed flow production. Thus, NISHIJIN is suitable for e-Textile production, which requires rapid prototyping and mass production of very complicated patterns. The authors prototyped and evaluated a few vests to take twelve-lead electrocardiogram. The result tells that the prototypes obtains electrocardiogram, which is good enough for diagnosis.


Assuntos
Vestuário , Eletrocardiografia/instrumentação , Monitorização Ambulatorial/instrumentação , Têxteis , Condutividade Elétrica , Eletrocardiografia/métodos , Desenho de Equipamento , Humanos , Monitorização Ambulatorial/métodos , Cloreto de Polivinila/química
16.
Artigo em Inglês | MEDLINE | ID: mdl-23848762

RESUMO

We study statistics of entanglement generated by quantum chaotic dynamics. Using an ensemble of the very large number (>/~10(7)) of quantum states obtained from the temporally evolving coupled kicked tops, we verify that the estimated one-body distribution of the squared Schmidt eigenvalues for the quantum chaotic dynamics can agree surprisingly well with the analytical one for the universality class of the random matrices described by the fixed trace ensemble (FTE). In order to quantify this agreement, we introduce the L(1) norm of the difference between the one-body distributions for the quantum chaos and FTE and use it as an indicator of the dynamical randomness. As we increase the scaled coupling constant, the L(1) difference decreases. When the effective Planck constant is not small enough, the decrease saturates, which implies quantum suppression of dynamical randomness. On the other hand, when the effective Planck constant is small enough, the decrease of the L(1) difference continues until it is masked by statistical fluctuation due to finiteness of the ensemble. Furthermore, we carry out two statistical analyses, the χ(2) goodness of fit test and an autocorrelation analysis, on the difference between the distributions to seek for dynamical remnants buried under the statistical fluctuation. We observe that almost all fluctuating deviations are statistical. However, even for well-developed quantum chaos, unexpectedly, we find a slight nonstatistical deviation near the largest Schmidt eigenvalue. In this way, the statistics of Schmidt eigenvalues enables us to measure dynamical randomness of quantum chaos with reference to the random matrix theory of FTE.

18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 84(5 Pt 1): 051605, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22181428

RESUMO

Ice crystal growth experiments in heavy water were carried out under microgravity to investigate the morphological transition from a disk crystal to a dendrite. Surprisingly, however, no transition was observed, namely, the disk crystal or dendrite maintained its shape throughout the experiments, unlike the results obtained on the ground. Therefore, we introduce a growth model to understand disk growth. The Gibbs-Thomson effect is taken into account as a stabilization mechanism. The model is numerically solved by varying both an interfacial tension of the prism plane and supercooling so that the final sizes of the crystals can become almost the same to determine the interfacial tension. The results are compared with the typical experimental ones and thus the interfacial tension is estimated to be 20 mJ/m(2). Next, the model is solved under two supercooling conditions by using the estimated interfacial tension to understand stable growth. Comparisons between the numerical and experimental results show that our model explains well the microgravity experiments. It is also found that the experimental setup has the capability of controlling temperature on the order of 1/100 K.

19.
J Org Chem ; 75(16): 5573-9, 2010 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-20704431

RESUMO

The lactonamycin model aglycon 4 was synthesized from the trihalogenated benzene derivative 10. Ethynyltetraol 6 was prepared from 10 via carbon elongations, oxidative demethylation, a cycloaddition reaction with the diene derived from homophthalic anhydride, and dihydroxylation. Final E- and F-ring constructions from 6 were realized via a palladium-catalyzed cyclization-methoxycarbonylation, a stereoselective methanol addition, and lactonization, leading to the production of 4.


Assuntos
Ciclização , Indóis/síntese química , Indóis/química , Estrutura Molecular , Naftoquinonas/síntese química , Naftoquinonas/química , Estereoisomerismo
20.
Cell Struct Funct ; 35(1): 3-13, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20190463

RESUMO

Tumor progression is a complex process that involves the interaction of cancer cells with the cancer-surrounding stromal cells. The cancer stroma influences the cancer cell growth and metastatic potential. The EGF family growth factor HB-EGF is synthesized in cancer cells and plays pivotal roles in oncogenic transformation and tumor progression, but the contribution of HB-EGF expressed in tumor stromal cells to tumor growth remains unclear. In the present study, we found that HB-EGF was expressed in host-derived cancer stromal cells in xenograft and allograft mouse tumor models. CRM197 is a specific inhibitor of human HB-EGF that has no effect on mouse HB-EGF. To elucidate whether host-derived stromal HB-EGF contributes to tumor growth, we generated knock-in mice expressing a CRM197-inhibitable humanized mutant form of HB-EGF. Administration of CRM197 to humanized knock-in mice that were bearing tumors derived from human or mouse cancer cells revealed that inhibition of host-derived stromal HB-EGF by CRM197 significantly reduced tumor growth. These results suggest that HB-EGF in the cancer-associated stroma plays a significant role for tumor growth, and that the HB-EGF derived from the stroma, as well as that expressed by cancer cells, is a potential target for cancer therapy. The present results also suggest that the humanized HB-EGF knock-in mice could be utilized for pathophysiological studies of HB-EGF as well as the development of therapeutic strategies targeting HB-EGF.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/genética , Neoplasias/etiologia , Animais , Proteínas de Bactérias/uso terapêutico , Linhagem Celular Tumoral , Modelos Animais de Doenças , Progressão da Doença , Técnicas de Introdução de Genes , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Células Estromais/metabolismo , Transplante Heterólogo , Transplante Homólogo
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