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1.
Opt Express ; 30(20): 36813-36825, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36258603

RESUMO

We developed a mid-infrared spectroscopy system with high spectral resolution and a high signal-to-noise ratio using an extremely high-order germanium immersion grating. The spectroscopic system covers wavelengths from 3 to 5 µm and has a spectral resolution of 1 GHz with a single-shot bandwidth of 2 THz. We proposed a method of improving the signal-to-noise ratio and achieved a ratio of over 3000 with a data acquisition rate of 125 Hz in the presence of fluctuations in the light source and environment. A signal-to-noise ratio of 10,000 was achieved with 0.1-s integration for 100-µW mid-infrared light.

2.
Neuropathol Appl Neurobiol ; 48(3): e12787, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34927285

RESUMO

AIMS: Oculopharyngodistal myopathy (OPDM) is caused by the expansion of CGG repeats in NOTCH2NLC (OPDM_NOTCH2NLC) GIPC1 (OPDM_GIPC1), or LRP12 (OPDM_LRP12). Neuronal intranuclear inclusion disease (NIID) is clinically distinct from OPDM but is also caused by the expansion of CGG repeats in NOTCH2NLC, which may be an indicator of intranuclear inclusion in skin biopsy. We investigated the presence of intranuclear inclusions in skin biopsies from patients with OPDM and muscle diseases with a similar pathology to evaluate whether they will have similar diagnostic findings on skin biopsy. METHODS: We analysed the frequency of p62-positive intranuclear inclusions in sweat gland cells, adipocytes and fibroblasts in skin biopsy samples from patients with OPDM (OPDM_NOTCH2NLC [n = 2], OPDM_GIPC1 [n = 6] and OPDM_LRP12 [n = 3]), NIID (n = 1), OPMD (n = 1), IBM (n = 4) and GNE myopathy (n = 2). RESULTS: The p62-postive intranuclear inclusions were observed in all three cell types in both patients with OPDM_NOTCH2NLC and a patient with NIID, in at least one cell type in all six patients with OPDM_GIPC1, and all in three cell types in one of the three patients with OPDM_LRP12. These findings were not observed in patients with OPMD, IBM or GNE myopathy. CONCLUSION: Intranuclear inclusions in skin biopsy samples are not specific to NIID and are found in all three types of genetically confirmed OPDM, suggesting that the underlying mechanism of OPDM may be similar to NIID, regardless of causative genes.


Assuntos
Corpos de Inclusão Intranuclear , Distrofias Musculares , Biópsia , Humanos , Corpos de Inclusão Intranuclear/patologia , Distrofias Musculares/genética , Doenças Neurodegenerativas
3.
Am J Hum Genet ; 106(6): 793-804, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32413282

RESUMO

Oculopharyngodistal myopathy (OPDM) is an adult-onset inherited neuromuscular disorder characterized by progressive ptosis, external ophthalmoplegia, and weakness of the masseter, facial, pharyngeal, and distal limb muscles. The myopathological features are presence of rimmed vacuoles (RVs) in the muscle fibers and myopathic changes of differing severity. Inheritance is variable, with either putative autosomal-dominant or autosomal-recessive pattern. Here, using a comprehensive strategy combining whole-genome sequencing (WGS), long-read whole-genome sequencing (LRS), linkage analysis, repeat-primed polymerase chain reaction (RP-PCR), and fluorescence amplicon length analysis polymerase chain reaction (AL-PCR), we identified an abnormal GGC repeat expansion in the 5' UTR of GIPC1 in one out of four families and three sporadic case subjects from a Chinese OPDM cohort. Expanded GGC repeats were further confirmed as the cause of OPDM in an additional 2 out of 4 families and 6 out of 13 sporadic Chinese individuals with OPDM, as well as 7 out of 194 unrelated Japanese individuals with OPDM. Methylation, qRT-PCR, and western blot analysis indicated that GIPC1 mRNA levels were increased while protein levels were unaltered in OPDM-affected individuals. RNA sequencing indicated p53 signaling, vascular smooth muscle contraction, ubiquitin-mediated proteolysis, and ribosome pathways were involved in the pathogenic mechanisms of OPDM-affected individuals with GGC repeat expansion in GIPC1. This study provides further evidence that OPDM is associated with GGC repeat expansions in distinct genes and highly suggests that expanded GGC repeat units are essential in the pathogenesis of OPDM, regardless of the genes in which the expanded repeats are located.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Distrofias Musculares/genética , Adolescente , Adulto , Povo Asiático/genética , Cromossomos Humanos Par 19/genética , Metilação de DNA , Feminino , Humanos , Escore Lod , Masculino , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/patologia , Distrofias Musculares/patologia , Distrofias Musculares/fisiopatologia , Linhagem , RNA-Seq , Expansão das Repetições de Trinucleotídeos/genética , Proteína Supressora de Tumor p53/metabolismo , Adulto Jovem
4.
Biochem Biophys Res Commun ; 512(3): 584-590, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30914202

RESUMO

Glycosylphosphatidylinositol (GPI) is a glycolipid that anchors some proteins to the plasma membrane. This anchoring is catalyzed by a transamidase complex (TAC) composed of five subunits: PIG-K, GAA1, PIG-U, PIG-T, and PIG-S (Fig. 1A). PIG-K and GAA1 are predicted to catalyze the first and second steps during attachment of proproteins of GPI-anchored proteins (GPI-APs) to GPI. GPI may be delivered by PIG-U, and PIG-T is required for stability of all TAC subunits when overexpressed in cultured cells. However, protein stability of TAC has not been analyzed using loss-of-function mutants for each subunit. Herein, we analyzed the stability of TAC in knockout and/or knockdown mutants for each subunit. PIG-T and PIG-U, or PIG-T and GAA1, were mutually required for stability, and all three subunits were stable without PIG-S or PIG-K. However, these three subunits were essential for the stability of both PIG-S and PIG-K. By contrast, loss of PIG-S reduced the stability of PIG-K and left the other subunits unaffected. Reduction of PIG-K did not impact any of the other subunits. Thus, PIG-T, PIG-U, and GAA1 may form a core complex associated by PIG-S, and these four subunits may stabilize PIG-K, triggering GPI anchoring reactions. Instability of PIG-K in the absence of the other four subunits may ensure that GPI anchoring is catalyzed only by the completely assembled complex.


Assuntos
Aminoaciltransferases/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas Ligadas por GPI/metabolismo , Aminoaciltransferases/genética , Animais , Sistemas CRISPR-Cas , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Estabilidade Enzimática , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo
5.
J Oleo Sci ; 62(1): 39-44, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23357816

RESUMO

Rapid synthesis of Gemini surfactants (C(12)-C(2)-C(12) and C(14)-C(6)-C(14)) by microwave heating is investigated. The yield of the synthesis of C(12)-C(2)-C(12) surfactant using 2.45-GHz microwaves was twice the yield obtained by the oil bath method. Moreover, the value of dielectric loss and microwave penetration depth for the sample solution suggest that the microwave frequency of 915 MHz (0.915 GHz) is preferable over the conventional frequency (2.45 GHz). A novel 915-MHz microwave organic synthesis apparatus with a closed reactor is proposed. The synthesis yields of C(12)-C(2)-C(12) obtained using the 915-MHz equipment were three to four times higher than those obtained using the conventional heating method.


Assuntos
Técnicas de Química Sintética/métodos , Micro-Ondas , Tensoativos/síntese química , Técnicas de Química Sintética/instrumentação , Fatores de Tempo
6.
Gan To Kagaku Ryoho ; 38(9): 1521-4, 2011 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-21918354

RESUMO

A 63-year-old man was found to have an upper abdominal mass, and was referred to our hospital. Endoscopic examination and abdominal CT showed gastric cancer with liver metastasis. A large metastatic tumor of the liver invaded the hepatic hilus, making curative resection impossible. We started chemotherapy using S-1(120 mg/body/day), orally administered for three weeks followed by 2-week rest period, and cisplatin(100mg/body), administered intravenously on day 8 as 1 course. After 5 courses of chemotherapy, the liver tumor reduced markedly and the gastric cancer pathologically disappeared, enabling partial gastrectomy and left hepatectomy. Histological examination showed a well-differentiated adenocarcinoma in the mucosal layer of the resected stomach. A resected specimen of the liver showed a moderately-differentiated adenocarcinoma with signet-ring cells, compatible to liver metastasis from gastric cancer. Bile leakage the remaining liver occurred, but he recovered soon. Gastrointestinal examination revealed another early gastric cancer after seeing him for 2 years on an outpatient basis. We conducted subtotal gastrectomy, and the patient remains alive 30 months after the first operation. This case suggests that S-1/CDDP chemotherapy may reduce the stage of unresectable liver metastasis from gastric cancer and make a curative operation possible.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/uso terapêutico , Gastrectomia , Hepatectomia , Neoplasias Hepáticas/tratamento farmacológico , Ácido Oxônico/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Tegafur/uso terapêutico , Cisplatino/administração & dosagem , Combinação de Medicamentos , Humanos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Ácido Oxônico/administração & dosagem , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Tegafur/administração & dosagem , Tomografia Computadorizada por Raios X
7.
Photochem Photobiol Sci ; 10(7): 1239-48, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21523270

RESUMO

A novel mercury-free Dewar-like (double-walled structure) microwave discharge thermally-insulated electrodeless lamp (MDTIEL) was fabricated and its performance evaluated using the photo-isomerization of trans-urocanic acid (trans-UA) in aqueous media as a test process driven by the emitted UV light when ignited with microwave radiation. The photo-isomerization processes trans-UA → cis-UA and cis-UA → trans-UA were re-visited using light emitted from a conventional high-pressure Hg light source and examined for the influence of UV light irradiance and solution temperature; the temperature dependence of the trans → cis process displayed a negative activation energy, E(a) = -1.3 cal mol(-1). To control the photo-isomerization of urocanic acid from the heat usually dissipated by a microwave discharge electrodeless lamp (single-walled MDEL), it was necessary to suppress the microwave-initiated heat. For comparison, the gas-fill in the MDEL lamp, which typically consists of a mixture of Hg and Ar, was changed to the more eco-friendly N(2) gas in the novel MDTIEL device. The dynamics of the photo-isomerization of urocanic acid driven by the UV wavelengths of the N(2)-MDTIEL light source were compared to those from the more conventional single-walled N(2)-MDEL and Hg/Ar-MDEL light sources, and with those from the Hg lamp used to irradiate, via a fiber optic, the photoreactor located in the wave-guide of the microwave apparatus. The heating efficiency of a solution with the double-walled N(2)-MDTIEL was compared to the efficiency from the single-walled N(2)-MDEL device. Advantages of N(2)-MDTIEL are described from a comparison of the dynamics of the trans-UA → cis-UA process on the basis of unit surface area of the lamp and unit power consumption. The considerably lower temperature on the external surface of the N(2)-MDTIEL light source should make it attractive in carrying out photochemical reactions that may be heat-sensitive such as the photothermochromic urocanic acid system.


Assuntos
Micro-Ondas , Raios Ultravioleta , Ácido Urocânico/química , Concentração de Íons de Hidrogênio , Isomerismo , Temperatura , Água/química
8.
Plant Physiol ; 130(1): 504-13, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12226529

RESUMO

Cytochrome P450 enzymes of the closely related CYP90 and CYP85 families catalyze essential oxidative reactions in the biosynthesis of brassinosteroid (BR) hormones. Arabidopsis CYP90B1/DWF4 and CYP90A1/CPD are responsible for respective C-22 and C-23 hydroxylation of the steroid side chain and CYP85A1 catalyzes C-6 oxidation of 6-deoxo intermediates, whereas the functions of CYP90C1/ROT3, CYP90D1, and CYP85A2 are still unknown. Semiquantitative reverse transcriptase-polymerase chain reaction analyses show that transcript levels of CYP85 and CYP90 genes are down-regulated by brassinolide, the end product of the BR biosynthesis pathway. Feedback control of the CYP90C1, CYP90D1, and CYP85A2 genes by brassinolide suggests that the corresponding enzymes might also participate in BR synthesis. CYP85 and CYP90 mRNAs show strong and transient accumulation during the 1st week of seedling development, as well as characteristic organ-specific distribution. Transcripts of CYP90A1 and CYP85A2 are preferentially represented in shoots and CYP90C1, CYP90D1, and CYP85A1 mRNAs are more abundant in roots, whereas CYP90B1 is ubiquitously expressed. Remarkably, the spatial pattern of CYP90A1 expression is maintained in the BR-insensitive cbb2 mutant, indicating the independence of organ-specific and BR-dependent regulation. Quantitative gas chromatography-mass spectrometry analysis of endogenous BRs in shoots and roots of Arabidopsis, pea (Pisum sativum), and tomato (Lycopersicon esculentum) reveal similar partitioning patterns of BR intermediates in these species. Inverse correlation between CYP90A1/CPD transcript levels and the amounts of the CYP90A1 substrate 6-deoxocathasterone in shoots and roots suggests that transcriptional regulation plays an important role in controlling BR biosynthesis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis/genética , Colestanóis/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Esteroides Heterocíclicos/metabolismo , Arabidopsis/enzimologia , Arabidopsis/crescimento & desenvolvimento , Brassinosteroides , Colestanóis/química , Sistema Enzimático do Citocromo P-450/metabolismo , Evolução Molecular , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Germinação/genética , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Pisum sativum/genética , Pisum sativum/metabolismo , Filogenia , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/genética , Brotos de Planta/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Esteroide Hidroxilases/genética , Esteroide Hidroxilases/metabolismo , Esteroides Heterocíclicos/química , Transcrição Gênica
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