Publications by authors named "Fei Da"

Many estuaries experience eutrophication, deoxygenation and warming, with potential impacts on greenhouse gas emissions. However, the response of NO production to these changes is poorly constrained. Here we applied nitrogen isotope tracer incubations to measure NO production under experimentally manipulated changes in oxygen and temperature in the Chesapeake Bay-the largest estuary in the United States.

View Article and Find Full Text PDF

Background: Ionizing radiation-induced lung injury is caused by the initial inflammatory reaction and leads to advanced fibrosis of lung tissue. Adipose-derived stem cells (ASCs) are a type of mesenchymal stem cell that can differentiate into various functional cell types with broad application prospects in the treatment of tissue damage. The purpose of this study was to explore the protective effect of ASCs against radiation-induced lung injury and to provide a novel basis for prevention and treatment of radiation-induced lung injury.

View Article and Find Full Text PDF

The prognostic factors for elderly patients with cervical cancer differ from those of younger patients. Competitive risk events could cause biases in the Cox proportional hazards (PH) model. This study aimed to construct a competitive risk model (CRM) nomogram for patients aged > 65 years with nonmetastatic cervical cancer.

View Article and Find Full Text PDF

Purpose: Intestinal injury commonly occurs in radiation therapy, but its pathogenesis is not well understood. The relationship between irradiation-induced intestinal injury and bile acids (BAs) metabolism remains elusive. This study intends to clarify the role of BAs metabolism in irradiation-induced intestinal injury and the potential for supplementation with BAs to alleviate this injury.

View Article and Find Full Text PDF

Metformin, a first-line oral drug for type II diabetes mellitus, not only reduces blood glucose levels, but also has many other biological effects. Recent studies have been conducted to determine the protective effect of metformin in irradiation injuries. However, the results are controversial and mainly focus on the time of metformin administration.

View Article and Find Full Text PDF

Staphylococcal enterotoxin B (SEB), which is produced by the major human pathogen, Staphylococcus aureus, represents a powerful superantigenic toxin and is considered a bioweapon. However, the contribution of SEB to S. aureus pathogenesis has never been directly demonstrated with genetically defined mutants in clinically relevant strains.

View Article and Find Full Text PDF

Estuaries play an uncertain but potentially important role in the global carbon cycle via CO outgassing. The uncertainty mainly stems from the paucity of studies that document the full spatial and temporal variability of estuarine surface water partial pressure of carbon dioxide ( CO). Here, we explore the potential of utilizing the abundance of pH data from historical water quality monitoring programs to fill the data void via a case study of the mainstem Chesapeake Bay (eastern United States).

View Article and Find Full Text PDF

Background/aims: The synthesis and degradation processes involved in bone remodeling are critically regulated by osteoblasts and osteoclasts. The GLP-1 receptor agonist Exendin-4 is beneficial for osteoblast differentiation and increases the number of osteoblasts.

Methods: We constructed an ovariectomized model to evaluate the impact of Exendin-4 on bone formation in osteoporosis.

View Article and Find Full Text PDF

Coagulase-negative staphylococci (CoNS) are important nosocomial pathogens and the leading cause of sepsis. The second most frequently implicated species, after , is . However, we have a significant lack of knowledge about what causes virulence of , as virulence factors of this pathogen have remained virtually unexplored.

View Article and Find Full Text PDF

Bacterial sepsis is a major killer in hospitalized patients. Coagulase-negative staphylococci (CNS) with the leading species Staphylococcus epidermidis are the most frequent causes of nosocomial sepsis, with most infectious isolates being methicillin-resistant. However, which bacterial factors underlie the pathogenesis of CNS sepsis is unknown.

View Article and Find Full Text PDF

QseC is a membrane-bound histidine sensor kinase found in Gram-negative pathogens and is involved in the regulation of bacterial virulence. LED209, a QseC-specific inhibitor, significantly inhibits the virulence of several pathogens and partially protects infected mice from death by blocking QseC. However, the mechanism of its antibacterial effects remains unclear.

View Article and Find Full Text PDF

Staphylococcus aureus is associated with serious invasive infections and high mortality rates due to a large number of toxins released. The persistent increasing resistance of S. aureus has driven the need for new anti-infection agents and innovative therapeutic strategies.

View Article and Find Full Text PDF

Methicillin-resistant Staphylococcus aureus (MRSA) infections are becoming increasingly difficult to treat, owing to acquired antibiotic resistance. The emergence and spread of MRSA limit therapeutic options and require new therapeutic strategies, including novel MRSA-active antibiotics. Filamentous temperature-sensitive protein Z (FtsZ) is a highly conserved bacterial tubulin homologue that is essential for controlling the bacterial cell division process in different species of S.

View Article and Find Full Text PDF

Methicillin-resistant Staphylococci (MRS), methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus epidermidis (MRSE) have become a challenging problem in nosocomial infections and are connected with high morbidity and mortality rates. This is due to the increasing incidence of resistance to virtually all β-lactams and a wide variety of antimicrobials. The spread of MRS severely limits therapeutic options and generates the need for novel antibiotics that are able to combat MRS infections.

View Article and Find Full Text PDF

Background: Brain-derived neurotrophic factor (BDNF) and neurotrophin-4 (NT4) regulate the survival of gustatory neurons, axon growth and branching, and innervation of taste buds during development. These actions are largely, but not completely, mediated through the tyrosine kinase receptor, TrkB. Here, we investigated the role of p75, the other major receptor for BDNF and NT4, in the development of the taste system.

View Article and Find Full Text PDF

Brain-derived neurotrophic factor (BDNF) and neurotrophin-4 (NT-4) are two neurotrophins that play distinct roles in geniculate (taste) neuron survival, target innervation, and taste bud formation. These two neurotrophins both activate the tropomyosin-related kinase B (TrkB) receptor and the pan-neurotrophin receptor p75. Although the roles of these neurotrophins have been well studied, the degree to which BDNF and NT-4 act via TrkB to regulate taste development in vivo remains unclear.

View Article and Find Full Text PDF

Staphylococcus epidermidis is one of the most frequent causes of device-associated infections, because it is known to cause biofilms that grow on catheters or other surgical implants. The persistent increasing resistance of S. epidermidis and other coagulase-negative staphylococci (CoNS) has driven the need for newer antibacterial agents with innovative therapeutic strategies.

View Article and Find Full Text PDF
Article Synopsis
  • The treatment of antibiotic-resistant septicemia is challenging due to the induction of bacterial resistance by traditional antibiotics, highlighting the need for new antibiotic drugs.
  • Amino-terminated Poly(amidoamine) dendrimers (PAMAM-NH(2)), specifically generation 2 (G2.0), show significant antibacterial effects against both antibiotic-sensitive and resistant strains while exhibiting low toxicity to human cells and not promoting resistance in bacteria.
  • In animal studies, G2.0 PAMAM-NH(2) drastically improved survival rates in mice infected with resistant bacteria, indicating its potential as a safe and effective broad-spectrum antibiotic.
View Article and Find Full Text PDF

In consideration of high production costs of new antimicrobial drugs, a more convenient and economical method for time-kill study is urgently required. In the present experiment, we attempted to demonstrate the feasibility of microplate method as an alternative measure of macrodilution method for time-kill study. Three conventional antibiotics (ciprofloxacin, ceftazidime, and levofloxacin) and two antimicrobial peptides [A-thanatin and K(4)-S4(1-16)a] were used to determine time-kill curves against Escherichia coli ATCC 25922 and Staphylococcus epidermidis ATCC 14990.

View Article and Find Full Text PDF

Menthol is a widely-used cooling and flavoring agent derived from mint leaves. In the peripheral nervous system, menthol regulates sensory transduction by activating TRPM8 channels residing specifically in primary sensory neurons. Although behavioral studies have implicated menthol actions in the brain, no direct central target of menthol has been identified.

View Article and Find Full Text PDF

Functional glycine receptors (GlyRs) are enriched in the hippocampus, but their role in hippocampal function remains unclear. Since the concentration of ambient glycine is determined by the presence of powerful glycine transporter (GlyT), we blocked the reuptake of glycine in hippocampal slices to examine the role of GlyRs. Antagonists of GlyT type 1 (GlyT1) but not that of GlyT type 2 (GlyT2) induced excitatory postsynaptic potential (EPSP)-spike depression, which was reversed by the specific GlyR antagonist strychnine.

View Article and Find Full Text PDF