23 research outputs found

    Parental legacy and regulatory novelty in Brachypodium diurnal transcriptomes accompanying their polyploidy

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    Polyploidy is a widespread phenomenon in eukaryotes that can lead to phenotypic novelty and has important implications for evolution and diversification. The modification of phenotypes in polyploids relative to their diploid progenitors may be associated with altered gene expression. However, it is largely unknown how interactions between duplicated genes affect their diurnal expression in allopolyploid species. In this study, we explored parental legacy and hybrid novelty in the transcriptomes of an allopolyploid species and its diploid progenitors. We compared the diurnal transcriptomes of representative Brachypodium cytotypes, including the allotetraploid Brachypodium hybridum and its diploid progenitors Brachypodium distachyon and Brachypodium stacei. We also artificially induced an autotetraploid B. distachyon. We identified patterns of homoeolog expression bias (HEB) across Brachypodium cytotypes and time-dependent gain and loss of HEB in B. hybridum. Furthermore, we established that many genes with diurnal expression experienced HEB, while their expression patterns and peak times were correlated between homoeologs in B. hybridum relative to B. distachyon and B. stacei, suggesting diurnal synchronization of homoeolog expression in B. hybridum. Our findings provide insight into the parental legacy and hybrid novelty associated with polyploidy in Brachypodium, and highlight the evolutionary consequences of diurnal transcriptional regulation that accompanied allopolyploidy

    Nr5a1 suppression during the murine fetal period optimizes ovarian development by fine-tuning Notch signaling

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    The nuclear receptor NR5A1 is equally expressed and required for development of the gonadal primordia of both sexes, but, after sex determination, it is upregulated in XY testes and downregulated in XX ovaries. We have recently demonstrated, in mice, that this downregulation is mediated by forkhead box L2 (FOXL2) and hypothesized that adequate suppression of Nr5a1 is essential for normal ovarian development. Further, analysis of human patients with disorders/differences of sex development suggests that overexpression of NR5A1 can result in XX (ovo)testicular development. Here, we tested the role of Nr5a1 by overexpression in fetal gonads using a Wt1-BAC (bacterial artificial chromosome) transgene system. Enforced Nr5a1 expression compromised ovarian development in 46,XX mice, resulting in late-onset infertility, but did not induce (ovo)testis differentiation. The phenotype was similar to that of XX mice lacking Notch signaling. The expression level of Notch2 was significantly reduced in Nr5a1 transgenic mice, and the ovarian phenotype was almost completely rescued by in utero treatment with a NOTCH2 agonist. We conclude that suppression of Nr5a1 during the fetal period optimizes ovarian development by finetuning Notch signaling

    Physiological and Ultrastructural Studies on the Origin of Activator Calcium in Body Wall Muscles of Spoon Worms

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    To examine the origin of activator Ca and its translocation during contraction in body wall muscles (BWM) of spoon worms, Urechis unicinctus , physiological and ultrastructural studies, including cytochemistry, were performed. The potassium (K-) contracture tension was significantly reduced by the removal of external Ca, and by the application of Mn, La and verapamil. On the other hand, caffeine induced a prolonged contraction. The removal of Ca and Mg from the external solution, and the rapid cooling caused an irregular or oscillatory contraction. These results suggested that, in BWM fibers, the activator Ca is supplied partially from both external solution and intracellular Ca-accumulating structures. Ultrastructural observations revealed that the muscle fibers contain a relatively large amount of sarcoplasmic reticulum (SR). The fractional volume of the SR relative to the fiber volume was 2~5% in all fibers of three muscle layers. To demonstrate the Ca localization, the muscle fibers were fixed by pyroantimonate (PA) methods at resting and contracting states. In the resting fibers, the PA precipitates were exclusively localized in the SR and the inner surface of plasma membrane. On the other hand, in the contracting fibers, they were diffusely distributed in the central regions of myoplasm, and had disappeared from the SR and plasma membrane. X-ray microanalysis revealed that the PA precipitates contain Ca. With the results of physiological experiments, these results indicate that the activator Ca originates not only from the external solution, but also from the intracellular Ca-accumulating structures, the SR and the inner surface of plasma membrane.Full-Length Pape

    A case of left frontal high-grade glioma diagnosed during pregnancy

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    Abstract Background As pregnancy accelerates glioma growth, therapeutic abortion has been recommended prior to tumor resection. Additionally, it has also been suggested that the extent of glioma resection is closely correlated with patient survival. Case presentation A 162-cm, 61.4-kg, 30-year-old, right-handed primigravida was referred to our institution at 21 weeks gestation to obtain a second opinion. At 18 weeks gestation, the patient developed new-onset generalized convulsive seizures (GCSs), which were poorly controlled by anticonvulsant polytherapy, early in the second trimester. A 6-cm lesion located in her left frontal supplementary motor area (SMA) was suspected as a grade III glioma, classified according to the World Health Organization (WHO) guidelines. Due to the limited evidence on the use of adjuvant therapy during pregnancy, tumors causing neurological symptoms and seizures must be treated, in order to stabilize the maternal condition and enable a safe birth. In the case of pregnant patients, awake craniotomy using intraoperative magnetic resonance imaging (iMRI) is considered advantageous, achieving gross total resection with a reduction of direct cortical stimulation, which may induce seizure, and so reducing fetal exposure to anesthetics. The “Asleep-Awake-Asleep” technique was performed at 27 weeks and 2 days gestation. As use of propofol in pregnant patients is prohibited, general anesthesia was maintained through administration of sevoflurane and remifentanil until the first scan of iMRI, and was subsequently re-induced with dexmedetomidine when tumor removal had been accomplished. A supraglottic airway (SGA) was used until the patient’s cranium was opened. There were no complications during either the procedure or the post-operative period. At 35 weeks gestation, the patient delivered a healthy baby of 2317 g. Pathological examination of the patient, revealed an anaplastic astrocytoma, thus radiotherapy and chemotherapy began 2 months post-delivery. There is no evidence of tumor recurrence in the patient and the child did not show any medical or developmental concerns at the point of the 17-month follow-up. Conclusions Since evidence on the use of adjuvant therapy during pregnancy is limited, extensive resection with functional monitoring is recommended if a brain tumor is presumed to be malignant. Awake craniotomy is considered advantageous to pregnant patients because subjective movement preserves the patient’s motor function and reduces fetal exposure to anesthetics. Therefore, providing multidisciplinary discussion takes place within the decision-making process, as well as careful perioperative preparation, awake craniotomy should be considered, even in the case of pregnant patients

    A case of chronic hepatitis B merged with acute fatty liver of pregnancy with severe coagulopathy

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    Abstract Background Acute fatty liver of pregnancy (AFLP) is a life-threatening disorder, and its relevance to viral hepatitis B (HB) remains unknown. This case presents an initial experience of treating a patient with HB progressing to AFLP throughout pregnancy; anesthesiologists should also recognize its clinical feature for perioperative management. Case presentation A 28-year-old parturient was diagnosed as chronic HB (CHB) at 21 weeks gestation. Liver and kidney dysfunction appeared rapidly at 34 weeks gestation, suspected as acute exacerbation of either CHB or AFLP. Emergency cesarean section was carried out, after which maternal disseminated intravascular coagulation and hypothermia persisted. With multidisciplinary management, the patient and infant were discharged on postpartum days 64 and 12, respectively. Conclusions Active CHB develops into AFLP. Antiviral therapy should be considered for parturient patients with CHB, particularly for those with high viral load. The most favorable outcome is prompt and accurate diagnosis to establish suitable termination method

    Obstructive Fecalomas in an Infant Treated with Successful Endoscopic Disimpaction

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    A fecaloma is a mass of accumulated feces with a consistency much harder than that of a fecal impaction. It is most frequently observed in the rectum and sigmoid area, and associated complications include colonic obstruction, ulceration, bleeding, and perforation. A one-year-old, previously healthy boy with no history of chronic constipation was admitted because of vomiting and abdominal distension. An abdominal computed tomography scan showed small and large bowel distension due to multiple obstructive fecalomas in the transverse colon. As the fecalomas could not be resolved by laxatives, enemas, or colonic lavage, endoscopic disimpaction under general anesthesia was attempted. Repeatedly shaving the fecalomas with biopsy forceps finally resulted in gradual fragmentation with subsequent passage. Gastrointestinal food allergy was later suggested as the cause because eosinophilic infiltration was found in a biopsy specimen of the colon wall. Endoscopic disimpaction is an effective treatment approach for addressing fecalomas to avoid more invasive surgical intervention

    Inhibitors of CLK Protein Kinases Suppress Cell Growth and Induce Apoptosis by Modulating Pre-mRNA Splicing

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    <div><p>Accumulating evidence has demonstrated the importance of alternative splicing in various physiological processes, including the development of different diseases. CDC-like kinases (CLKs) and serine-arginine protein kinases (SRPKs) are components of the splicing machinery that are crucial for exon selection. The discovery of small molecule inhibitors against these kinases is of significant value, not only to delineate the molecular mechanisms of splicing, but also to identify potential therapeutic opportunities. Here we describe a series of small molecules that inhibit CLKs and SRPKs and thereby modulate pre-mRNA splicing. Treatment with these small molecules (Cpd-1, Cpd-2, or Cpd-3) significantly reduced the levels of endogenous phosphorylated SR proteins and caused enlargement of nuclear speckles in MDA-MB-468 cells. Additionally, the compounds resulted in splicing alterations of <i>RPS6KB1</i> (<i>S6K</i>), and subsequent depletion of S6K protein. Interestingly, the activity of compounds selective for CLKs was well correlated with the activity for modulating <i>S6K</i> splicing as well as growth inhibition of cancer cells. A comprehensive mRNA sequencing approach revealed that the inhibitors induced splicing alterations and protein depletion for multiple genes, including those involved in growth and survival pathways such as S6K, EGFR, EIF3D, and PARP. Fluorescence pulse-chase labeling analyses demonstrated that isoforms with premature termination codons generated after treatment with the CLK inhibitors were degraded much faster than canonical mRNAs. Taken together, these results suggest that CLK inhibitors exhibit growth suppression and apoptosis induction through splicing alterations in genes involved in growth and survival. These small molecule inhibitors may be valuable tools for elucidating the molecular machinery of splicing and for the potential development of a novel class of antitumor agents.</p></div
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