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Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a central role in cholesterol homeostasis in humans as a major regulator of LDLR levels. PCSK9 is an intriguing protease in that it does not act by proteolysis but by preventing LDLR recirculation from endosomes to the plasma membrane. This, and the inexistence of any other proteolytic substrate but itself could suggest that PCSK9 is an exquisite example of evolutionary fine-tuning. However, the gene has been lost in several mammalian species, and null alleles are present (albeit at low frequencies) in some human populations without apparently deleterious health effects, raising the possibility that the PCSK9 may have become dispensable in the mammalian lineage. To address this issue, we systematically recovered, assembled, corrected, annotated and analysed publicly available PCSK9 sequences for 420 eutherian species to determine the distribution, frequencies, mechanisms and timing of PCSK9 pseudogenization events, as well as the evolutionary pressures underlying the preservation or loss of the gene. We found a dramatic difference in the patterns of PCSK9 retention and loss between Euarchontoglires-where there is strong pressure for gene preservation-and Laurasiatheria, where multiple independent events have led to PCSK9 loss in most species. These results suggest that there is a fundamental difference in the regulation of cholesterol metabolism between Euarchontoglires and Laurasiatheria, which in turn has important implications for the use of Laurasiatheria species (e.g. pigs) as animal models of human cholesterol-related diseases.
As a late mediator of sepsis, the role of high mobility group box 1 (HMGB1) has been recognized as important, and suppression of HMGB1 release and restoration of vascular barrier integrity are regarded as potentially promising therapeutic strategies for sepsis. For repositioning of previously FDA-approved drugs to develop new therapies for human diseases, screening of chemical compound libraries, biological active, is an efficient method. Our study illustrates an example of drug repositioning of Biapenem (BIPM), a carbapenem antibiotic, for the modulation of HMGB1-induced septic responses.
We tested our hypothesis that BIPM inhibits HMGB1-induced vascular hyperpermeability and thereby increases the survival of septic mouse model from suppression of HMGB1 release upon lipopolysaccharide (LPS)-stimulation. In LPS-activated human umbilical vein endothelial cells (HUVECs) and a cecal ligation and puncture (CLP)-induced sepsis mouse model, antiseptic activity of BIPM was investigated from suppression of vascular permeability, pro-inflammatory proteins, and markers for tissue injury.
BIPM significantly suppressed release of HMGB1 both in LPS-activated HUVECs (upto 60%) and the CLP-induced sepsis mouse model (upto 54%). BIPM inhibited hyperpermeability (upto 59%) and reduced HMGB1-mediated vascular disruptions (upto 62%), mortality (upto 50%), and also tissue injury including lung, liver, and kidney in mice.
Reduction of HMGB1 release and septic mortality by BIPM (in vitro, from 5 to 15μM for 6h; in vivo, from 0.37 to 1.1mg/kg, 24h) indicate a possibility of successful repositioning of BIPM for the treatment of sepsis.
Reduction of HMGB1 release and septic mortality by BIPM (in vitro, from 5 to 15 μM for 6 h; in vivo, from 0.37 to 1.1 mg/kg, 24 h) indicate a possibility of successful repositioning of BIPM for the treatment of sepsis.A 25-year-old man was initially diagnosed with a giant mediastinal nonseminomatous germ cell tumor. Chemotherapy was administered and the tumor markers were normalized; however, the tumor grew in size (20 cm), invading the left brachiocephalic vein (BCV) and the superior vena cava (SVC). Bilateral transmanubrial approach with median sternotomy and bilateral clamshell thoracotomy was required for the complete resection of the giant tumor with the SVC reconstruction. Bilateral TMA provided the surgical field of view around the bilateral phrenic nerves and bilateral BCVs. click here Given the final pathological diagnosis of the mature teratoma, this was considered growing teratoma syndrome where surgery is the only treatment option.
To investigate whether blood-brain barrier (BBB) served a key role in the edema-relief effect of bloodletting puncture at hand twelve Jing-well points (HTWP) in traumatic brain injury (TBI) and the potential molecular signaling pathways.
Adult male Sprague-Dawley rats were assigned to the sham-operated (sham), TBI, and bloodletting puncture (bloodletting) groups (n=24 per group) using a randomized number table. The TBI model rats were induced by cortical contusion and then bloodletting puncture were performed at HTWP twice a day for 2 days. The neurological function and cerebral edema were evaluated by modified neurological severity score (mNSS), cerebral water content, magnetic resonance imaging and hematoxylin and eosin staining. Cerebral blood flow was measured by laser speckles. The protein levels of aquaporin 4 (AQP4), matrix metalloproteinases 9 (MMP9) and mitogen-activated protein kinase pathway (MAPK) signaling were detected by immunofluorescence staining and Western blot.
Compared with TBI groupromising therapeutic strategy for TBI-induced cerebral edema.
To explore the antitumor effects of ethanol extract from Ventilago leiocarpa Benth (EEVLB) on sarcoma 180 (S180) tumor-bearing mice and the potential mechanism.
Sixty mice were randomly assigned to 6 groups according to a random number table normal group, model group, 5-fluorouracil (5-FU) group (0.02 g·kg
), and high-, medium-, low-dose EEVLB groups (100, 84, and 56 g of raw material·kg
body weight, respectively), with 10 mice each group. All treatments were given once daily for 10 consecutive days. Effects of EEVLB on inhibiting tumor growth and immune function in mice were evaluated among all groups after the treatments by detecting tumor inhibition rate, organ index, serum levels of interleukin (IL)-2, -6, -10, CD3
CD4
T lymphocytes, CD4
/CD8
ratio, caspase-3 and Bcl-2.
EEVLB with different concentrations achieved inhibition of tumor growth in vivo, wherein the high-dose group showed the most significant reduction in tumor weight and increased apoptosis of tumor cells (P<0.05). In addition, both net weight gain and spleen index of mice showed uptrend in EEVLB treatment groups (P<0.