95 research outputs found
Chromosomal Dynamics at the Shh Locus: Limb Bud-Specific Differential Regulation of Competence and Active Transcription
The expression of Sonic hedgehog (Shh) in mouse limb buds is regulated by a long-range enhancer 1 Mb upstream of the Shh promoter. We used 3D-FISH and chromosome conformation capture assays to track changes at the Shh locus and found that long-range promoter-enhancer interactions are specific to limb bud tissues competent to express Shh. However, the Shh locus loops out from its chromosome territory only in the posterior limb bud (zone of polarizing activity or ZPA), where Shh expression is active. Notably, while Shh mRNA is detected throughout the ZPA, enhancer-promoter interactions and looping out were only observed in small fractions of ZPA cells. In situ detection of nascent Shh transcripts and unstable EGFP reporters revealed that active Shh transcription is likewise only seen in a small fraction of ZPA cells. These results suggest that chromosome conformation dynamics at the Shh locus allow transient pulses of Shh transcription
HCO3--independent rescue from apoptosis by stilbene derivatives in rat cardiomyocytes
AbstractApoptosis of rat cardiomyocytes induced by staurosporine is prevented by a stilbene derivative (DIDS), which is a known blocker of both Cl-/HCO3- exchangers and Cl− channels. To clarify its target, staurosporine-induced activation of caspase-3, DNA laddering and cell death were examined in cultured rat cardiomyocytes. Removal of ambient HCO3-, which minimizes the function of Cl-/HCO3- exchangers, failed to affect the preventive effect of DIDS on apoptosis. A carboxylate analog Cl− channel blocker, which does not block Cl-/HCO3- exchangers, also inhibited apoptotic events. Thus, rescue by DIDS of cardiomyocytes from apoptosis is mediated by blockage of Cl− channels
Chromosomal Dynamics at the Shh Locus: Limb Bud-Specific Differential Regulation of Competence and Active Transcription
SummaryThe expression of Sonic hedgehog (Shh) in mouse limb buds is regulated by a long-range enhancer 1 Mb upstream of the Shh promoter. We used 3D-FISH and chromosome conformation capture assays to track changes at the Shh locus and found that long-range promoter-enhancer interactions are specific to limb bud tissues competent to express Shh. However, the Shh locus loops out from its chromosome territory only in the posterior limb bud (zone of polarizing activity or ZPA), where Shh expression is active. Notably, while Shh mRNA is detected throughout the ZPA, enhancer-promoter interactions and looping out were only observed in small fractions of ZPA cells. In situ detection of nascent Shh transcripts and unstable EGFP reporters revealed that active Shh transcription is likewise only seen in a small fraction of ZPA cells. These results suggest that chromosome conformation dynamics at the Shh locus allow transient pulses of Shh transcription
Higher enhanced computed tomography attenuation value of the aorta is a predictor of massive transfusion in blunt trauma patients
Objective Several scoring systems have been developed to identify patients who require massive transfusion (MT) after major trauma to improve survival. The primary goal of this study was to investigate the usefulness of enhanced computed tomography attenuation values (CTAVs) of major vessels to determine the need for MT in patients with major blunt trauma. Methods This single-center retrospective cohort study evaluated patients aged 16 years or older who underwent contrast-enhanced computed tomography scan of the torso after major blunt trauma. The CTAVs of six major vessel points in both the arterial and portal venous phases at initial computed tomography examination were assessed and compared between the MT and the no MT group. The capability of enhanced CTAVs to predict the necessity for MT was estimated based on the area under the receiver operating characteristic curve. Results Of the 254 eligible patients, 36 (14%) were in the MT group. Patients in the MT group had significantly higher CTAVs at all sites except the inferior vena cava in both the arterial and portal venous phases than that in the no MT group. The descending aorta in the arterial phase had the highest accuracy for predicting MT, with an AUROC of 0.901 (95% confidence interval, 0.855 to 0.947; P<0.001). Conclusion Initial elevation of enhanced CTAV of the aorta is a predictor for the need for MT. A higher CTAV of the aorta should alert the trauma surgeon or emergency physician to activate their MT protocol
The role of melatonin as an antioxidant in the follicle
Melatonin (N-acetyl-5-methoxytryptamine) is secreted during the dark hours at night by pineal gland, and it regulates a variety of important central and peripheral actions related to circadian rhythms and reproduction. It has been believed that melatonin regulates ovarian function by the regulation of gonadotropin release in the hypothalamus-pituitary gland axis via its specific receptors. In addition to the receptor mediated action, the discovery of melatonin as a direct free radical scavenger has greatly broadened the understanding of melatonin's mechanisms which benefit reproductive physiology. Higher concentrations of melatonin have been found in human preovulatory follicular fluid compared to serum, and there is growing evidence of the direct effects of melatonin on ovarian function especially oocyte maturation and embryo development. Many scientists have focused on the direct role of melatonin on oocyte maturation and embryo development as an anti-oxidant to reduce oxidative stress induced by reactive oxygen species, which are produced during ovulation process. The beneficial effects of melatonin administration on oocyte maturation and embryo development have been confirmed by in vitro and in vivo experiments in animals. This review also discusses the first application of melatonin to the clinical treatment of infertile women and confirms that melatonin administration reduces intrafollicular oxidative damage and increase fertilization rates. This review summarizes our recent works and new findings related to the reported beneficial effects of melatonin on reproductive physiology in its role as a reducer of oxidative stress, especially on oocyte maturation and embryo development
Lineage-specific positive selection at the merozoite surface protein 1 (msp1) locus of Plasmodium vivax and related simian malaria parasites
<p>Abstract</p> <p>Background</p> <p>The 200 kDa merozoite surface protein 1 (MSP-1) of malaria parasites, a strong vaccine candidate, plays a key role during erythrocyte invasion and is a target of host protective immune response. <it>Plasmodium vivax</it>, the most widespread human malaria parasite, is closely related to parasites that infect Asian Old World monkeys, and has been considered to have become a parasite of man by host switch from a macaque malaria parasite. Several Asian monkey parasites have a range of natural hosts. The same parasite species shows different disease manifestations among host species. This suggests that host immune responses to <it>P. vivax</it>-related malaria parasites greatly differ among host species (albeit other factors). It is thus tempting to invoke that a major immune target parasite protein such as MSP-1 underwent unique evolution, depending on parasite species that exhibit difference in host range and host specificity.</p> <p>Results</p> <p>We performed comparative phylogenetic and population genetic analyses of the gene encoding MSP-1 (<it>msp1</it>) from <it>P. vivax </it>and nine <it>P. vivax</it>-related simian malaria parasites. The inferred phylogenetic tree of <it>msp1 </it>significantly differed from that of the mitochondrial genome, with a striking displacement of <it>P. vivax </it>from a position close to <it>P. cynomolgi </it>in the mitochondrial genome tree to an outlier of Asian monkey parasites. Importantly, positive selection was inferred for two ancestral branches, one leading to <it>P. inui </it>and <it>P. hylobati </it>and the other leading to <it>P. vivax</it>, <it>P. fieldi </it>and <it>P. cynomolgi</it>. This ancestral positive selection was estimated to have occurred three to six million years ago, coinciding with the period of radiation of Asian macaques. Comparisons of <it>msp1 </it>polymorphisms between <it>P. vivax</it>, <it>P. inui </it>and <it>P. cynomolgi </it>revealed that while some positively selected amino acid sites or regions are shared by these parasites, amino acid changes greatly differ, suggesting that diversifying selection is acting species-specifically on <it>msp1</it>.</p> <p>Conclusions</p> <p>The present results indicate that the <it>msp1 </it>locus of <it>P. vivax </it>and related parasite species has lineage-specific unique evolutionary history with positive selection. <it>P. vivax </it>and related simian malaria parasites offer an interesting system toward understanding host species-dependent adaptive evolution of immune-target surface antigen genes such as <it>msp1</it>.</p
Development and validation of a new scoring system for prognostic prediction of community-acquired pneumonia in older adults
The discriminative power of CURB-65 for mortality in community-acquired pneumonia (CAP) is suspected to decrease with age. However, a useful prognostic prediction model for older patients with CAP has not been established. This study aimed to develop and validate a new scoring system for predicting mortality in older patients with CAP. We recruited two prospective cohorts including patients aged ≥ 65 years and hospitalized with CAP. In the derivation (n = 872) and validation cohorts (n = 1, 158), the average age was 82.0 and 80.6 years and the 30-day mortality rate was 7.6% (n = 66) and 7.4% (n = 86), respectively. A new scoring system was developed based on factors associated with 30-day mortality, identified by multivariate analysis in the derivation cohort. This scoring system named CHUBA comprised five variables: confusion, hypoxemia (SpO2 ≤ 90% or PaO2 ≤ 60 mmHg), blood urea nitrogen ≥ 30 mg/dL, bedridden state, and serum albumin level ≤ 3.0 g/dL. With regard to 30-day mortality, the area under the receiver operating characteristic curve for CURB-65 and CHUBA was 0.672 (95% confidence interval, 0.607–0.732) and 0.809 (95% confidence interval, 0.751–0.856; P < 0.001), respectively. The effectiveness of CHUBA was statistically confirmed in the external validation cohort. In conclusion, a simpler novel scoring system, CHUBA, was established for predicting mortality in older patients with CAP
A complex rearrangement between APC and TP63 associated with familial adenomatous polyposis identified by multimodal genomic analysis: a case report
Genetic testing of the APC gene by sequencing analysis and MLPA is available across commercial laboratories for the definitive genetic diagnosis of familial adenomatous polyposis (FAP). However, some genetic alterations are difficult to detect using conventional analyses. Here, we report a case of a complex genomic APC-TP63 rearrangement, which was identified in a patient with FAP by a series of genomic analyses, including multigene panel testing, chromosomal analyses, and long-read sequencing. A woman in her thirties was diagnosed with FAP due to multiple polyps in her colon and underwent total colectomy. Subsequent examination revealed fundic gland polyposis. No family history suggesting FAP was noted except for a first-degree relative with desmoid fibromatosis. The conventional APC gene testing was performed by her former doctor, but no pathogenic variant was detected, except for 2 variants of unknown significance. The patient was referred to our hospital for further genetic analysis. After obtaining informed consent in genetic counseling, we conducted a multigene panel analysis. As insertion of a part of the TP63 sequence was detected within exon16 of APC, further analyses, including chromosomal analysis and long-read sequencing, were performed and a complex translocation between chromosomes 3 and 5 containing several breakpoints in TP63 and APC was identified. No phenotype associated with TP63 pathogenic variants, such as split-hand/foot malformation (SHFM) or ectrodactyly, ectodermal dysplasia, or cleft lip/palate syndrome (EEC) was identified in the patient or her relatives. Multimodal genomic analyses should be considered in cases where no pathogenic germline variants are detected by conventional genetic testing despite an evident medical or family history of hereditary cancer syndromes
Pneumonia Caused by Severe Acute Respiratory Syndrome Coronavirus 2 and Influenza Virus: A Multicenter Comparative Study
Background: Detailed differences in clinical information between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia (CP), which is the main phenotype of SARS-CoV-2 disease, and influenza pneumonia (IP) are still unclear. Methods: A prospective, multicenter cohort study was conducted by including patients with CP who were hospitalized between January and June 2020 and a retrospective cohort of patients with IP hospitalized from 2009 to 2020. We compared the clinical presentations and studied the prognostic factors of CP and IP. Results: Compared with the IP group (n = 66), in the multivariate analysis, the CP group (n = 362) had a lower percentage of patients with underlying asthma or chronic obstructive pulmonary disease (P < .01), lower neutrophil-to-lymphocyte ratio (P < .01), lower systolic blood pressure (P < .01), higher diastolic blood pressure (P < .01), lower aspartate aminotransferase level (P < .05), higher serum sodium level (P < .05), and more frequent multilobar infiltrates (P < .05). The diagnostic scoring system based on these findings showed excellent differentiation between CP and IP (area under the receiver operating characteristic curve, 0.889). Moreover, the prognostic predictors were different between CP and IP. Conclusions: Comprehensive differences between CP and IP were revealed, highlighting the need for early differentiation between these 2 pneumonias in clinical settings
Development of mirror-polishing process technology for difficult-to-polish materials
Mirror-polishing processes have recently been required to add high quality, high-precision precision and multi-functionality to industrial products. However, this requires skilled manual work, making it difficult to improve productivity. Automatic polishing of these products is also very difficult. Furthermore, mirror-polishing process of stainless steel, titanium and glass, which are often used in high-value-added medical products, is also difficult. Therefore, in this study, a technology for high-precision, automatic mirror polishing of three difficult-to-polish materials - stainless steel, titanium and glass - was developed and evaluated. First, the difficult-to-polish properties of different materials were considered, and then tools were developed to improve these properties and enable suitable mirror-polishing processes. Next, a polishing slurry was developed to improve the surface roughness (Rz = 0.1 μm or less). Finally, the optimum polishing conditions for the proposed mirror-polishing process were determined by design of experiment and then evaluated. It was concluded that; (1) In order to perform mirror-polishing processes of three types of workpieces, stainless steel (SUS304), titanium (pure titanium) and glass (quartz glass), new polishing tool and slurries corresponding to each material were developed and the optimum polishing processing conditions were clarified, (2) Using (1), mirror-polishing processes of each material with a surface roughness of Rz = 0.1 μm has been achieved
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