Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Nat Commun ; 12(1): 4498, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301931

RESUMO

In animal germlines, PIWI proteins and the associated PIWI-interacting RNAs (piRNAs) protect genome integrity by silencing transposons. Here we report the extensive sequence and quantitative correlations between 2',3'-cyclic phosphate-containing RNAs (cP-RNAs), identified using cP-RNA-seq, and piRNAs in the Bombyx germ cell line and mouse testes. The cP-RNAs containing 5'-phosphate (P-cP-RNAs) identified by P-cP-RNA-seq harbor highly consistent 5'-end positions as the piRNAs and are loaded onto PIWI protein, suggesting their direct utilization as piRNA precursors. We identified Bombyx RNase Kappa (BmRNase κ) as a mitochondria-associated endoribonuclease which produces cP-RNAs during piRNA biogenesis. BmRNase κ-depletion elevated transposon levels and disrupted a piRNA-mediated sex determination in Bombyx embryos, indicating the crucial roles of BmRNase κ in piRNA biogenesis and embryonic development. Our results reveal a BmRNase κ-engaged piRNA biogenesis pathway, in which the generation of cP-RNAs promotes robust piRNA production.


Assuntos
Endorribonucleases/genética , Perfilação da Expressão Gênica/métodos , Proteínas de Insetos/genética , RNA Interferente Pequeno/genética , RNA/genética , Animais , Sequência de Bases , Bombyx , Linhagem Celular , Endorribonucleases/metabolismo , Feminino , Proteínas de Insetos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Mutação , Ácidos Fosfatídicos/química , RNA/química , RNA/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , RNA-Seq/métodos , Testículo/metabolismo
3.
Methods ; 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33962012

RESUMO

RNA cleavages by many ribonucleases generate RNA molecules that contain a 2',3'-cyclic phosphate (cP) at their 3'-termini, and many cP-containing RNAs (cP-RNAs) are expressed as functional molecules in cells and tissues. 5'-tRNA half molecules are representative examples of functional cP-RNAs, playing important roles in various biological processes. We here show in vitro production of cP-containing 5'-tRNA half molecules that is able to prepare abundant synthetic cP-RNAs enough for functional analyses. Furthermore, we report a multiplex TaqMan RT-qPCR method which can simultaneously quantify multiple cP-containing 5'-tRNA half species. The method enabled us to efficiently quantify 5'-tRNA halves using samples with limited amounts, such as human plasma samples, revealing drastic enhancement of 5'-tRNA half levels at approximately 1,000-fold in patients infected with Mycobacterium tuberculosis. These in vitro production and multiplex quantification methods can be applied to any cP-RNAs, and they provide cost-effective, in-house techniques to accelerate expressional and functional characterizations of 5'-tRNA halves and other cP-RNAs.

5.
Sci Rep ; 11(1): 1186, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441894

RESUMO

We aimed to investigate the effects of maternal tadalafil therapy on fetal programming of metabolic function in a mouse model of fetal growth restriction (FGR). Pregnant C57BL6 mice were divided into the control, L-NG-nitroarginine methyl ester (L-NAME), and tadalafil + L-NAME groups. Six weeks after birth, the male pups in each group were given a high-fat diet. A glucose tolerance test (GTT) was performed at 15 weeks and the pups were euthanized at 20 weeks. We then assessed the histological changes in the liver and adipose tissue, and the adipocytokine production. We found that the non-alcoholic fatty liver disease activity score was higher in the L-NAME group than in the control group (p < 0.05). Although the M1 macrophage numbers were significantly higher in the L-NAME/high-fat diet group (p < 0.001), maternal tadalafil administration prevented this change. Moreover, the epididymal adipocyte size was significantly larger in the L-NAME group than in the control group. This was also improved by maternal tadalafil administration (p < 0.05). Further, we found that resistin levels were significantly lower in the L-NAME group compared to the control group (p < 0.05). The combination of exposure to maternal L-NAME and a high-fat diet induced glucose impairment and non-alcoholic fatty liver disease. However, maternal tadalafil administration prevented these complications. Thus, deleterious fetal programming caused by FGR might be modified by in utero intervention with tadalafil.


Assuntos
Adipócitos/efeitos dos fármacos , Retardo do Crescimento Fetal/tratamento farmacológico , Hipertrofia/prevenção & controle , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Tadalafila/farmacologia , Animais , Dieta Hiperlipídica/efeitos adversos , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Teste de Tolerância a Glucose/métodos , Hipertensão/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NG-Nitroarginina Metil Éster/farmacologia , Gravidez
6.
Carbohydr Polym ; 251: 116993, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142564

RESUMO

Sake, a traditional Japanese rice wine, contains various oligosaccharides (Sake oligosaccharides; SAOs) derived from rice starch. We previously found that SAOs reach a high degree of polymerization (DP). In this study, we developed a hydrophilic interaction liquid chromatography-time-of-flight/mass spectrometry (HILIC-TOF/MS) based analytical method to separate isomeric SAOs. Isomers of SAOs with DP = 6, 7, and 8, which were named DP6-1, DP7-1, DP8-1 and DP8-2, respectively, were purified from sake and their structures were determined by two-dimensional NMR spectroscopy. These were novel oligosaccharides containing two α-1, 6 bonded branches on an α-1, 4-linked glucose main chain. Interestingly, adjacent double α-1, 6 branches that have not been identified in starch, were found in DP6-1, DP7-1, and DP8-1, suggesting the presence of the branching pattern in starch. DP6-1 was poorly digested by fungal glucoamylase, and this may be attributed to its adjacent double branches at the non-reducing end.


Assuntos
Oligossacarídeos/química , Vinho/análise , Configuração de Carboidratos , Sequência de Carboidratos , Fermentação , Proteínas Fúngicas/metabolismo , Glucana 1,4-alfa-Glucosidase/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Isomerismo , Japão , Espectrometria de Massas , Ressonância Magnética Nuclear Biomolecular , Oryza/química , Amido/química
7.
Nat Chem Biol ; 15(12): 1148-1155, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31740832

RESUMO

Archaeosine (G+), 7-formamidino-7-deazaguanosine, is an archaea-specific modified nucleoside found at the 15th position of tRNAs. In Euryarchaeota, 7-cyano-7-deazaguanine (preQ0)-containing tRNA (q0N-tRNA), synthesized by archaeal tRNA-guanine transglycosylase (ArcTGT), has been believed to be converted to G+-containing tRNA (G+-tRNA) by the paralog of ArcTGT, ArcS. However, we found that several euryarchaeal ArcSs have lysine transfer activity to q0N-tRNA to form q0kN-tRNA, which has a preQ0 lysine adduct as a base. Through comparative genomics and biochemical experiments, we found that ArcS forms a robust complex with a radical S-adenosylmethionine (SAM) enzyme named RaSEA. The ArcS-RaSEA complex anaerobically converted q0N-tRNA to G+-tRNA in the presence of SAM and lysine via q0kN-tRNA. We propose that ArcS and RaSEA should be considered an archaeosine synthase α-subunit (lysine transferase) and ß-subunit (q0kN-tRNA lyase), respectively.


Assuntos
Enzimas/metabolismo , Guanosina/análogos & derivados , S-Adenosilmetionina/metabolismo , Bases de Dados Genéticas , Enzimas/genética , Perfilação da Expressão Gênica , Guanosina/biossíntese , Lisina/metabolismo , Especificidade por Substrato
8.
PLoS Genet ; 15(11): e1008469, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31721758

RESUMO

RNA molecules generated by ribonuclease cleavage sometimes harbor a 2',3'-cyclic phosphate (cP) at their 3'-ends. Those cP-containing RNAs (cP-RNAs) form a hidden layer of transcriptome because standard RNA-seq cannot capture them as a result of cP's prevention of an adapter ligation reaction. Here we provide genome-wide analyses of short cP-RNA transcriptome across multiple mouse tissues. Using cP-RNA-seq that can exclusively sequence cP-RNAs, we identified numerous novel cP-RNA species which are mainly derived from cytoplasmic tRNAs, mRNAs, and rRNAs. Determination of the processing sites of substrate RNAs for cP-RNA generation revealed highly-specific RNA cleavage events between cytidine and adenosine in cP-RNA biogenesis. cP-RNAs were not evenly derived from the overall region of substrate RNAs but rather from specific sites, implying that cP-RNAs are not from random degradation but are produced through a regulated biogenesis pathway. The identified cP-RNAs were abundantly accumulated in mouse tissues, and the expression levels of cP-RNAs showed age-dependent reduction. These analyses of cP-RNA transcriptome unravel a novel, abundant class of non-coding RNAs whose expression could have physiological roles.


Assuntos
Envelhecimento/genética , Sequência de Bases/genética , RNA/genética , Transcriptoma/genética , Envelhecimento/patologia , Animais , Regulação da Expressão Gênica/genética , Genômica , Humanos , Camundongos , Fosfatos/química , Fosfatos/metabolismo , RNA/química , Clivagem do RNA/genética , RNA Ribossômico/genética , RNA Nucleolar Pequeno/genética , RNA de Transferência/genética , RNA não Traduzido/genética , Análise de Sequência de RNA
9.
Sci Rep ; 9(1): 13136, 2019 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511549

RESUMO

Carotenoid production in some non-phototropic bacteria occurs in a light-dependent manner to protect cells from photo-oxidants. Knowledge regarding the transcriptional regulator involved in the light-dependent production of carotenoids of non-phototrophic bacteria has been mainly confined to coenzyme B12-based photo-sensitive regulator CarH/LitR family proteins belonging to a MerR family transcriptional regulator. In this study, we found that bacteria belonging to Micrococcales and Corynebacteriales exhibit light-dependent carotenoid-like pigment production including an amino acid-producer Corynebacterium glutamicum AJ1511. CrtR is a putative MarR family transcriptional regulator located in the divergent region of a carotenoid biosynthesis gene cluster in the genome of those bacteria. A null mutant for crtR of C. glutamicum AJ1511 exhibited constitutive production of carotenoids independent of light. A complemented strain of the crtR mutant produced carotenoids in a light-dependent manner. Transcriptional analysis revealed that the expression of carotenoid biosynthesis genes is regulated in a light-dependent manner in the wild type, while the transcription was upregulated in the crtR mutant irrespective of light. In vitro experiments demonstrated that a recombinant CrtR protein binds to the specific sequences within the intergenic region of crtR and crtE, which corresponds to -58 to -7 for crtE, and +26 to -28 for crtR with respect to the transcriptional start site, and serves as a repressor for crtE transcription directed by RNA polymerase containing SigA. Taken together, the results indicate that CrtR light-dependently controls the expression of the carotenoid gene cluster in C. glutamicum and probably closely related Actinobacteria.


Assuntos
Proteínas de Bactérias/genética , Carotenoides/metabolismo , Corynebacterium glutamicum/genética , Regulação Bacteriana da Expressão Gênica/efeitos da radiação , Luz , Transcrição Genética/efeitos da radiação , Sequência de Aminoácidos , Proteínas de Bactérias/metabolismo , Sequência de Bases , Corynebacterium glutamicum/metabolismo , Família Multigênica/genética , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sítio de Iniciação de Transcrição
10.
Medicine (Baltimore) ; 97(49): e13563, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30544475

RESUMO

RATIONALE: An association between inflammatory myopathy and malignancy has been recognized particularly in patients positive for anti-transcription intermediary factor 1γ (TIF1γ) antibody. We report a case of anti-TIF1γ antibody positive dermatomyositis (DM) associated with thymic carcinoma which radiographically mimicked benign tumor. PATIENT CONCERNS: A 72-year-old man presented typical characteristic cutaneous manifestations and proximal muscle weakness with elevated levels of myogenic enzymes. An anterior mediastinal tumor was detected by computed tomography (CT) scan and radiographically assessed to be benign with distinct borders and little enhancement. DIAGNOSES: DM with anti-TIF1γ antibody and thymic carcinoma. INTERVENTIONS: Thymic carcinoma was completely resected by surgery. DM was induced into remission with glucocorticoid treatment. OUTCOMES: The serum level of myogenic enzyme remained within normal range under low-dose glucocorticoid maintenance. No evidence of carcinoma recurrence with CT scan was observed at 1-year follow up. LESSONS: The present case indicated that anti-TIF1γ antibody would play a role as the "autoimmune tumor marker" in patients with inflammatory myopathy.


Assuntos
Autoanticorpos/sangue , Dermatomiosite/sangue , Timoma/sangue , Neoplasias do Timo/sangue , Fatores de Transcrição/imunologia , Idoso , Biomarcadores/sangue , Dermatomiosite/complicações , Dermatomiosite/diagnóstico , Dermatomiosite/tratamento farmacológico , Diagnóstico Diferencial , Humanos , Masculino , Timoma/complicações , Timoma/diagnóstico por imagem , Timoma/cirurgia , Neoplasias do Timo/complicações , Neoplasias do Timo/diagnóstico por imagem , Neoplasias do Timo/cirurgia
11.
Front Genet ; 9: 562, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30538719

RESUMO

Cellular RNA molecules contain phosphate or hydroxyl ends. A 2',3'-cyclic phosphate (cP) is one of the 3'-terminal forms of RNAs mainly generated from RNA cleavage by ribonucleases. Although transcriptome profiling using RNA-seq has become a ubiquitous tool in biological and medical research, cP-containing RNAs (cP-RNAs) form a hidden transcriptome layer, which is infrequently recognized and characterized, because standard RNA-seq is unable to capture them. Despite cP-RNAs' invisibility in RNA-seq data, increasing evidence indicates that they are not accumulated simply as non-functional degradation products; rather, they have physiological roles in various biological processes, designating them as noteworthy functional molecules. This review summarizes our current knowledge of cP-RNA biogenesis pathways and their catalytic enzymatic activities, discusses how the cP-RNA generation affects biological processes, and explores future directions to further investigate cP-RNA biology.

12.
Microorganisms ; 6(4)2018 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-30347855

RESUMO

To date, numerous modified nucleosides in tRNA as well as tRNA modification enzymes have been identified not only in thermophiles but also in mesophiles. Because most modified nucleosides in tRNA from thermophiles are common to those in tRNA from mesophiles, they are considered to work essentially in steps of protein synthesis at high temperatures. At high temperatures, the structure of unmodified tRNA will be disrupted. Therefore, thermophiles must possess strategies to stabilize tRNA structures. To this end, several thermophile-specific modified nucleosides in tRNA have been identified. Other factors such as RNA-binding proteins and polyamines contribute to the stability of tRNA at high temperatures. Thermus thermophilus, which is an extreme-thermophilic eubacterium, can adapt its protein synthesis system in response to temperature changes via the network of modified nucleosides in tRNA and tRNA modification enzymes. Notably, tRNA modification enzymes from thermophiles are very stable. Therefore, they have been utilized for biochemical and structural studies. In the future, thermostable tRNA modification enzymes may be useful as biotechnology tools and may be utilized for medical science.

13.
Anal Chem ; 89(20): 10783-10789, 2017 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-28972746

RESUMO

Claudins (CLs) are membrane proteins found in tight junctions and play a major role in establishing the intercellular barrier. However, some CLs are abnormally overexpressed on tumor cells and are valid clinical biomarkers for cancer diagnosis. Here, we constructed antibody Fab fragment-based Quenchbodies (Q-bodies) as effective and reliable fluorescent sensors for detecting and visualizing CLs on live tumor cells. The variable region genes for anti-CL1 and anti-CL4 antibodies were used to express recombinant Fab fragments, and clones recognizing CL4 with high affinity were selected for making Q-bodies. When two fluorescent dyes were conjugated to the N-terminal tags attached to the Fab, the fluorescent signal was significantly increased after adding nanomolar-levels of purified CL4. Moreover, addition of the Q-body to CL4-expressing cells including CL4-positive cancer cells led to a clear fluorescence signal with low background, even without washing steps. Our findings suggested that such Q-bodies would serve as a potent tool for specifically illuminating membrane targets expressed on cancer cells, both in vitro and in vivo.


Assuntos
Claudinas/análise , Fragmentos Fab das Imunoglobulinas/imunologia , Microscopia Confocal , Biomarcadores Tumorais/análise , Linhagem Celular Tumoral , Claudinas/imunologia , Corantes Fluorescentes/química , Humanos , Fragmentos Fab das Imunoglobulinas/genética , Fragmentos Fab das Imunoglobulinas/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Espectrometria de Fluorescência , Junções Íntimas/metabolismo
14.
Nucleic Acids Res ; 45(15): 9108-9120, 2017 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-28645172

RESUMO

Transfer RNAs (tRNAs) function in translational machinery and further serves as a source of short non-coding RNAs (ncRNAs). tRNA-derived ncRNAs show differential expression profiles and play roles in many biological processes beyond translation. Molecular mechanisms that shape and regulate their expression profiles are largely unknown. Here, we report the mechanism of biogenesis for tRNA-derived Piwi-interacting RNAs (td-piRNAs) expressed in Bombyx BmN4 cells. In the cells, two cytoplasmic tRNA species, tRNAAspGUC and tRNAHisGUG, served as major sources for td-piRNAs, which were derived from the 5'-part of the respective tRNAs. cP-RNA-seq identified the two tRNAs as major substrates for the 5'-tRNA halves as well, suggesting a previously uncharacterized link between 5'-tRNA halves and td-piRNAs. An increase in levels of the 5'-tRNA halves, induced by BmNSun2 knockdown, enhanced the td-piRNA expression levels without quantitative change in mature tRNAs, indicating that 5'-tRNA halves, not mature tRNAs, are the direct precursors for td-piRNAs. For the generation of tRNAHisGUG-derived piRNAs, BmThg1l-mediated nucleotide addition to -1 position of tRNAHisGUG was required, revealing an important function of BmThg1l in piRNA biogenesis. Our study advances the understanding of biogenesis mechanisms and the genesis of specific expression profiles for tRNA-derived ncRNAs.


Assuntos
Proteínas Argonauta/genética , Bombyx/genética , Proteínas de Insetos/genética , RNA Interferente Pequeno/genética , RNA de Transferência de Ácido Aspártico/genética , RNA de Transferência de Histidina/genética , Animais , Proteínas Argonauta/metabolismo , Sequência de Bases , Bombyx/crescimento & desenvolvimento , Bombyx/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Células Germinativas/crescimento & desenvolvimento , Células Germinativas/metabolismo , Proteínas de Insetos/metabolismo , Conformação de Ácido Nucleico , RNA Interferente Pequeno/metabolismo , RNA de Transferência de Ácido Aspártico/metabolismo , RNA de Transferência de Histidina/metabolismo
15.
Sci Rep ; 7(1): 4110, 2017 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-28646211

RESUMO

Piwi proteins and their bound Piwi-interacting RNAs (piRNAs) are predominantly expressed in the germline and play crucial roles in germline development by silencing transposons and other targets. Bombyx mori BmN4 cells are culturable germ cells that equip the piRNA pathway. Because of the scarcity of piRNA-expressing culturable cells, BmN4 cells are being utilized for the analyses of piRNA biogenesis. We here report that the piRNA biogenesis in BmN4 cells is regulated by cell density. As cell density increased, the abundance of Piwi proteins and piRNA biogenesis factors was commonly upregulated, resulting in an increased number of perinuclear nuage-like granules where Piwi proteins localize. Along with these phenomena, the abundance of mature piRNAs also globally increased, whereas levels of long piRNA precursor and transposons decreased, suggesting that increasing cell density promotes piRNA biogenesis pathway and that the resultant accumulation of mature piRNAs is functionally significant for transposon silencing. Our study reveals a previously uncharacterized link between cell density and piRNA biogenesis, designates cell density as a critical variable in piRNA studies using BmN4 cell system, and suggests the alteration of cell density as a useful tool to monitor piRNA biogenesis and function.


Assuntos
Bombyx/genética , Células Germinativas/metabolismo , RNA Interferente Pequeno/genética , Animais , Contagem de Células , Linhagem Celular , Células Cultivadas , Biologia Computacional , Grânulos Citoplasmáticos/metabolismo , Elementos de DNA Transponíveis , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo
16.
J Obstet Gynaecol Res ; 43(4): 705-709, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28127819

RESUMO

AIM: Cervical cancer onset initially occurs during youth. Papanicolaou tests performed in early pregnancy can detect cervical cancer; however, Papanicolaou tests during pregnancy have been noted to be inaccurate, reflecting changes associated with pregnancy. Therefore, we assessed the effect of pregnancy on Papanicolaou test results. METHODS: Of 1351 pregnant women who delivered at Ise Red Cross Hospital between January 2010 and December 2014, 1213 underwent Papanicolaou tests at early pregnancy and post-partum. We compared the Papanicolaou test results. RESULTS: The results of the Papanicolaou test were different in 32 patients. Of the 1191 patients negative for intraepithelial lesions or malignancy in early pregnancy, 16 had other cytological abnormalities post-partum. We performed therapeutic conization post-partum in four patients. The Papanicolaou test results in early pregnancy of the four patients were negative for intraepithelial lesions or malignancy in one patient, atypical squamous cells of undetermined significance in one and high-grade squamous intraepithelial lesion in two. CONCLUSION: The results of the Papanicolaou test during pregnancy may not be accurate because of the influence of hormones associated with pregnancy. Taking advantage of the one-month post-partum screening visit can lead to early detection and treatment of cervical cancer in young people.


Assuntos
Teste de Papanicolaou/normas , Complicações Neoplásicas na Gravidez/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Esfregaço Vaginal/normas , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Transtornos Puerperais/diagnóstico , Sensibilidade e Especificidade , Adulto Jovem
17.
J Matern Fetal Neonatal Med ; 29(23): 3812-4, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26820698

RESUMO

OBJECTIVE: We assessed the utility of the pulse oximeter perfusion index (PI) in maternal monitoring immediately after delivery. METHODS: We examined 30 pregnant women without any complications using the Rad7 device at delivery. The correlations between heart rate (HR), systolic blood pressure (BP), oxygen saturation SpO2, PI, Pleth variability index (PVI), shock index and blood loss were assessed. RESULTS: Blood loss at 20-min postpartum was not correlated with the difference in heart rate, systolic BP, SpO2, shock index or PVI taken immediately after delivery and at 20-min postpartum, but showed a strong negative correlation with the difference in the PI taken immediately after delivery and at 20-min postpartum (r = -0.70). CONCLUSION: PI changes were correlated with post-delivery blood loss and can be used for maternal monitoring at delivery.


Assuntos
Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Oximetria/métodos , Oxigênio/sangue , Hemorragia Pós-Parto/diagnóstico , Adulto , Parto Obstétrico , Feminino , Humanos , Cuidado Pós-Natal , Gravidez
18.
Nucleic Acids Res ; 44(4): 1894-908, 2016 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-26721388

RESUMO

Archaeosine (G(+)), which is found only at position 15 in many archaeal tRNA, is formed by two steps, the replacement of the guanine base with preQ0 by archaeosine tRNA-guanine transglycosylase (ArcTGT) and the subsequent modification of preQ0 to G(+) by archaeosine synthase. However, tRNA(Leu) from Thermoplasma acidophilum, a thermo-acidophilic archaeon, exceptionally has two G(+)13 and G(+)15 modifications. In this study, we focused on the biosynthesis mechanism of G(+)13 and G(+)15 modifications in this tRNA(Leu). Purified ArcTGT from Pyrococcus horikoshii, for which the tRNA recognition mechanism and structure were previously characterized, exchanged only the G15 base in a tRNA(Leu) transcript with (14)C-guanine. In contrast, T. acidophilum cell extract exchanged both G13 and G15 bases. Because T. acidophilum ArcTGT could not be expressed as a soluble protein in Escherichia coli, we employed an expression system using another thermophilic archaeon, Thermococcus kodakarensis. The arcTGT gene in T. kodakarensis was disrupted, complemented with the T. acidophilum arcTGT gene, and tRNA(Leu) variants were expressed. Mass spectrometry analysis of purified tRNA(Leu) variants revealed the modifications of G(+)13 and G(+)15 in the wild-type tRNA(Leu). Thus, T. acidophilum ArcTGT has a multisite specificity and is responsible for the formation of both G(+)13 and G(+)15 modifications.


Assuntos
Glicosídeo Hidrolases/genética , Complexos Multienzimáticos/genética , RNA de Transferência/genética , Thermoplasma/enzimologia , Transferases/genética , Regulação Enzimológica da Expressão Gênica , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/metabolismo , Complexos Multienzimáticos/química , Complexos Multienzimáticos/metabolismo , Pyrococcus horikoshii/enzimologia , Thermoplasma/genética , Transferases/química , Transferases/metabolismo
19.
Int Med Case Rep J ; 9: 1-4, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26719729

RESUMO

Uterine rupture rarely occurs during pregnancy, but it is a critical situation if so. It is already known that a history of uterine surgeries, such as cesarean section or myomectomy, is a risk factor for uterine rupture. Currently, the laparoscopic adenomyomectomy is a widely performed procedure, but associated risks have not been defined. We observed a case of spontaneous uterine rupture in a patient during the 35th week of gestation, after a laparoscopic adenomyomectomy. A 42-year-old, gravida 2, para 0 woman became pregnant after a laparoscopic adenomyomectomy and her pregnancy was conventional. At a scheduled date in the 35th week of gestation, after combined spinal epidural anesthesia and frequent uterine contractions, a weak pain suddenly ensued. After 13 minutes of uterine contractions, vaginal bleeding was evident. A cesarean section was performed, and the uterine rupture was found in the scar. After a laparoscopic adenomyomectomy, a pregnant uterus can easily rupture by rather weak and short uterine contractions, and is characterized by vaginal bleeding. When uterine bleeding is observed in pregnant women that have a history of adenomyomectomy, one should consider uterine rupture.

20.
Intern Med ; 54(17): 2219-23, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26328650

RESUMO

A 45-year-old woman under home parenteral nutrition was admitted with recurrent fever and a worsening renal function. A diagnosis of central venous catheter-related blood stream infection (CVCRBSI) was made according to the identification of coagulase-negative Staphylococcus from both the peripheral blood and the removed CV catheter, along with an improvement of the symptoms following the removal of the catheter. Renal impairment with hypocomplementemia was thought to be secondary to the immune complex formation and deposition in the kidneys in response to prolonged bacteremia. This was confirmed by the pathological findings. Clinicians should therefore be aware that glomerulonephritis may be induced by long-term CVCRBSI.


Assuntos
Bacteriemia/complicações , Bacteriemia/etiologia , Infecções Relacionadas a Cateter/complicações , Cateteres de Demora/microbiologia , Glomerulonefrite/etiologia , Nutrição Parenteral no Domicílio/efeitos adversos , Infecções Estafilocócicas/complicações , Bacteriemia/diagnóstico , Bacteriemia/microbiologia , Infecções Relacionadas a Cateter/microbiologia , Cateterismo Venoso Central/efeitos adversos , Cateteres de Demora/efeitos adversos , Feminino , Glomerulonefrite/microbiologia , Glomerulonefrite/patologia , Humanos , Pessoa de Meia-Idade , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...