45 research outputs found
Duplication and Remolding of tRNA Genes in the Mitochondrial Genome of \u3cem\u3eReduvius tenebrosus\u3c/em\u3e (Hemiptera: Reduviidae)
Most assassin bugs are predators that act as important natural enemies of insect pests. Mitochondrial (mt) genomes of these insects are double-strand circular DNAs that encode 37 genes. In the present study, we explore the duplication and rearrangement of tRNA genes in the mt genome of Reduvius tenebrosus, the first mt genome from the subfamily Reduviinae. The gene order rearranges from CR (control region)-trnI-trnQ-trnM-ND2 to CR-trnQ-trnI2-trnI1-trnM-ND2. We identified 23 tRNA genes, including 22 tRNAs commonly found in insects and an additional trnI (trnI2), which has high sequence similarity to trnM. We found several pseudo genes, such as pseudo-trnI, pseudo-CR, and pseudo-ND2, in the hotspot region of gene rearrangement (between the control region and ND2). These features provided evidence that this novel gene order could be explained by the tandem duplication/random loss (TDRL) model. The tRNA duplication/anticodon mutation mechanism further explains the presence of trnI2, which is remolded from a duplicated trnM in the TDRL process (through an anticodon mutation of CAT to GAT). Our study also raises new questions as to whether the two events proceed simultaneously and if the remolded tRNA gene is fully functional. Significantly, the duplicated tRNA gene in the mitochondrial genome has evolved independently at least two times within assassin bugs
Limited Regeneration Potential with Minimal Epicardial Progenitor Conversions in the Neonatal Mouse Heart after Injury
The regeneration capacity of neonatal mouse heart is controversial. In addition, whether epicardial cells provide a progenitor pool for de novo heart regeneration is incompletely defined. Following apical resection of the neonatal mouse heart, we observed limited regeneration potential. Fate-mapping of Tbx18MerCreMer mice revealed that newly formed coronary vessels and a limited number of cardiomyocytes were derived from the T-box transcription factor 18 (Tbx18) lineage. However, further lineage tracing with SM-MHCCreERT2 and Nfactc1Cre mice revealed that the new smooth muscle and endothelial cells are in fact derivatives of pre-existing coronary vessels. Our data show that neonatal mouse heart can regenerate but that its potential is limited. Moreover, although epicardial cells are multipotent during embryogenesis, their contribution to heart repair through "stem" or "progenitor" cell conversion is minimal after birth. These observations suggest that early embryonic heart development and postnatal heart regeneration are distinct biological processes. Multipotency of epicardial cells is significantly decreased after birth
Cloud-Magnetic Resonance Imaging System: In the Era of 6G and Artificial Intelligence
Magnetic Resonance Imaging (MRI) plays an important role in medical
diagnosis, generating petabytes of image data annually in large hospitals. This
voluminous data stream requires a significant amount of network bandwidth and
extensive storage infrastructure. Additionally, local data processing demands
substantial manpower and hardware investments. Data isolation across different
healthcare institutions hinders cross-institutional collaboration in clinics
and research. In this work, we anticipate an innovative MRI system and its four
generations that integrate emerging distributed cloud computing, 6G bandwidth,
edge computing, federated learning, and blockchain technology. This system is
called Cloud-MRI, aiming at solving the problems of MRI data storage security,
transmission speed, AI algorithm maintenance, hardware upgrading, and
collaborative work. The workflow commences with the transformation of k-space
raw data into the standardized Imaging Society for Magnetic Resonance in
Medicine Raw Data (ISMRMRD) format. Then, the data are uploaded to the cloud or
edge nodes for fast image reconstruction, neural network training, and
automatic analysis. Then, the outcomes are seamlessly transmitted to clinics or
research institutes for diagnosis and other services. The Cloud-MRI system will
save the raw imaging data, reduce the risk of data loss, facilitate
inter-institutional medical collaboration, and finally improve diagnostic
accuracy and work efficiency.Comment: 4pages, 5figures, letter
Cardiac Sca-1+ cells are not intrinsic stem cells for myocardial development, renewal and repair
Background:
For over a decade, Sca-1+ cells within the mouse heart have been widely recognized as a stem cell population with multipotency that can give rise to cardiomyocytes, endothelial cells and smooth muscle cells in vitro and after cardiac grafting. However, the developmental origin and authentic nature of these cells remain elusive.
Methods:
Here, we used a series of high-fidelity genetic mouse models to characterize the identity and regenerative potential of cardiac resident Sca-1+ cells.
Results:
With these novel genetic mouse models, we found that Sca-1 does not label cardiac precursor cells during early embryonic heart formation. Postnatal cardiac resident Sca-1+ cells are in fact a pure endothelial cell population. They retain endothelial properties and exhibit minimal cardiomyogenic potential during development, normal aging and upon ischemic injury.
Conclusions:
Our study provides definitive insights into the nature of cardiac resident Sca-1+ cells. The observations challenge the current dogma that cardiac resident Sca-1+ cells are intrinsic stem cells for myocardial development, renewal and repair and suggest that the mechanisms of transplanted Sca-1+ cells in heart repair need to be reassessed
Henricohahnia Breddin 1900
Henricohahnia Breddin, 1900 Henricohahnia Breddin, 1900: 184; Distant, 1904: 387; Miller, 1954: 447; Hsiao & Ren, 1981: 484; Putshkov & Putshkov 1985: 46; Maldonado-Capriles 1990: 215; Putshkov & Putshkov 1996: 240. Forestus Distant, 1903: 251. Parasclomina Miller, 1948: 472. Type species. Henricohahnia wahnschaffei Breddin, 1900. Distribution. Oriental and Australian regions.Published as part of Zhao, Ping, Wang, Jianyun & Cai, Wanzhi, 2014, Description of a new species of the genus Henricohahnia Breddin (Hemiptera: Heteroptera: Reduviidae: Harpactorinae) from China, with a key to Chinese species, pp. 367-373 in Zootaxa 3811 (3) on page 368, DOI: 10.11646/zootaxa.3811.3.7, http://zenodo.org/record/22757
Renicoris robustus, a new genus and species of the subfamily Harpactorinae (Hemiptera, Reduviidae) from China
Renicoris gen. nov. and its type species Renicoris robustus sp. nov. (Hemiptera: Heteroptera: Reduviidae: Harpactorinae) from Yunnan, China, are described and illustrated. A key to separate the new genus and its closely related genera is provided
Ocelliemesina sinica, the second ocelli-bearing genus and species of thread-legged bugs (Hemiptera: Reduviidae: Emesinae)
Wang, Jianyun, Wang, Baohai, Cao, Liangming, Cai, Wanzhi (2015): Ocelliemesina sinica, the second ocelli-bearing genus and species of thread-legged bugs (Hemiptera: Reduviidae: Emesinae). Zootaxa 3936 (3): 429-434, DOI: 10.11646/zootaxa.3936.3.
Myocardial Tbx20 regulates early atrioventricular canal formation and endocardial epithelial-mesenchymal transition via Bmp2
During early embryogenesis, the formation of the cardiac atrioventricular canal (AVC) facilitates the transition of the heart from a linear tube into a chambered organ. However, the genetic pathways underlying this developmental process are poorly understood. The T-box transcription factor Tbx20 is expressed predominantly in the AVC of early heart tube. It was shown that Tbx20 activates Nmyc1 and suppresses Tbx2 expression to promote proliferation and specification of the atrial and ventricular chambers, yet it is not known if Tbx20 is involved in early AVC development. Here, we report that mice lacking Tbx20 in the AVC myocardium fail to form the AVC constriction, and the endocardial epithelial-mesenchymal transition (EMT) is severely perturbed. Tbx20 maintains expression of a variety of genes, including Bmp2, Tbx3 and Hand1 in the AVC myocardium. Intriguingly, we found Bmp2 downstream genes involved in the EMT initiation are also downregulated. In addition, re-expression of Bmp2 in the AVC myocardium substantially rescues the EMT defects resulting from the lack of Tbx20, suggesting Bmp2 is one of the key downstream targets of Tbx20 in AVC development. Our data support a complex signaling network with Tbx20 suppressing Tbx2 in the AVC myocardium but also indirectly promoting Tbx2 expression through Bmp2. The spatiotemporal expression of Tbx2 in the AVC appears to be balanced between these two opposing signals. Overall, our study provides genetic evidence that Tbx20 has essential roles in regulating AVC development that coordinate early cardiac chamber formatio
Duplication and Remolding of tRNA Genes in the Mitochondrial Genome of Reduvius tenebrosus (Hemiptera: Reduviidae)
Most assassin bugs are predators that act as important natural enemies of insect pests. Mitochondrial (mt) genomes of these insects are double-strand circular DNAs that encode 37 genes. In the present study, we explore the duplication and rearrangement of tRNA genes in the mt genome of Reduvius tenebrosus, the first mt genome from the subfamily Reduviinae. The gene order rearranges from CR (control region)-trnI-trnQ-trnM-ND2 to CR-trnQ-trnI2-trnI1-trnM-ND2. We identified 23 tRNA genes, including 22 tRNAs commonly found in insects and an additional trnI (trnI2), which has high sequence similarity to trnM. We found several pseudo genes, such as pseudo-trnI, pseudo-CR, and pseudo-ND2, in the hotspot region of gene rearrangement (between the control region and ND2). These features provided evidence that this novel gene order could be explained by the tandem duplication/random loss (TDRL) model. The tRNA duplication/anticodon mutation mechanism further explains the presence of trnI2, which is remolded from a duplicated trnM in the TDRL process (through an anticodon mutation of CAT to GAT). Our study also raises new questions as to whether the two events proceed simultaneously and if the remolded tRNA gene is fully functional. Significantly, the duplicated tRNA gene in the mitochondrial genome has evolved independently at least two times within assassin bugs
Clinical efficacy of alprostadil combined with α-lipoic acid in the treatment of elderly patients with diabetic nephropathy
To evaluate the effect and toxicity of alprostadil combined with thioctic acid injection in the treatment of patients with diabetic nephropathy (DN)