Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
Add more filters










Database
Language
Publication year range
1.
Acute Med Surg ; 11(1): e970, 2024.
Article in English | MEDLINE | ID: mdl-38948425

ABSTRACT

Aim: When treating burn patients, some patients die in the chronic phase, even if they overcome the acute phase of the burn. To elucidate the timing of death and its underlying causes among burn patients. Methods: Patients evaluated were admitted to our burn center between January 2015, and December 2019. Patient information, time, and cause of death were retrospectively collected from their medical records. Results: Among 342 admitted patients, 49 died. The time of death was as follows: within 24 h (n = 9), within 3 days (n = 7), within 1 week (n = 5), within 2 weeks (n = 4), within 3 weeks (n = 3), within 30 days (n = 6), within 60 days (n = 5), and after 60 days (n = 9). The causes of death within 3 days were hypoxic encephalopathy, extensive burns (>80%), severe heat stroke, and acute coronary syndrome. The causes of death after 3 days were sepsis, pneumonia, intestinal ischemia, pancreatitis, and worsening of chronic diseases. The mortality rate was similar for patients ≥65 years of age and those with a burn area of ≥20%, with both groups showing a particularly poor prognosis. Conclusions: The timing of death in hospitalized burn patients showed a bimodal distribution as approximately 40% of patients who survived the resuscitation period died after 30 days. Elderly patients were at particularly high risk for mortality. In burn care, treatment planning should consider not only the short-term but also the long-term prognosis.

2.
mSphere ; 4(2)2019 04 24.
Article in English | MEDLINE | ID: mdl-31019000

ABSTRACT

Bordetella pertussis, B. parapertussis, and B. bronchiseptica cause respiratory infections, many of which are characterized by coughing of the infected hosts. The pathogenesis of the coughing remains to be analyzed, mainly because there were no convenient infection models of small animals that replicate coughing after Bordetella infection. Here, we present a coughing model of rats infected with B. bronchiseptica Rats, which are one of natural hosts of B. bronchiseptica, were readily infected with the organisms and showed frequent coughing. B. pertussis also caused coughing in rats, which is consistent with previous reports, but the cough response was less apparent than the B. bronchiseptica-induced cough. By using the rat model, we demonstrated that adenylate cyclase toxin, dermonecrotic toxin, and the type III secretion system are not involved in cough production, but BspR/BtrA (different names for the same protein), an anti-σ factor, regulates the production of unknown factor(s) to cause coughing. Rat coughing was observed by inoculation of not only the living bacteria but also the bacterial lysates. Infection with bspR (btrA)-deficient strains caused significantly less frequent coughing than the wild type; however, intranasal inoculation of the lysates from a bspR (btrA)-deficient strain caused coughing similarly to the wild type, suggesting that BspR/BtrA regulates the production of the cough factor(s) only when the bacteria colonize host bodies. Moreover, the cough factor(s) was found to be heat labile and produced by B. bronchiseptica in the Bvg+ phase. We consider that our rat model provides insight into the pathogenesis of cough induced by the Bordetella infection.IMPORTANCE Whooping cough is a contagious respiratory disease caused by Bordetella pertussis This disease is characterized by severe paroxysmal coughing, which becomes a heavy burden for patients and occasionally results in death; however, its pathogenesis remains largely unknown. The major obstacle to analyzing Bordetella-induced coughing is the lack of conventional animal models that replicate coughing. As Bordetella pertussis is highly adapted to humans, infection models in experimental animals are not considered to be well established. In the present study, we examined coughing in rats infected with B. bronchiseptica, which shares many virulence factors with B. pertussis Using this rat model, we demonstrated that some of the major virulence factors of Bordetella are not involved in cough production, but an anti-σ factor, BspR/BtrA, of B. bronchiseptica regulates the production of unknown cough-causing bacterial factor(s). Our results provide important clues to understand the mechanism by which Bordetella induces cough.


Subject(s)
Bacterial Proteins/genetics , Bordetella bronchiseptica/genetics , Cough/etiology , Gene Expression Regulation, Bacterial , Sigma Factor/antagonists & inhibitors , Virulence Factors/genetics , Animals , Bordetella bronchiseptica/pathogenicity , Cough/microbiology , Disease Models, Animal , Female , Lung/microbiology , Rats , Rats, Wistar , Type III Secretion Systems/genetics
3.
Microbiol Immunol ; 55(3): 154-9, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21204952

ABSTRACT

Bordetella dermonecrotic toxin (DNT) affects the biological function of host cells by activating intracellular Rho GTPases. The toxin binds to unidentified receptor(s) via 54 N-terminal amino acids, undergoes intramolecular cleavage on the C-terminal side of Arg(44) by furin or furin-like protease, and eventually enters the cytoplasm where the Rho GTPases reside. The binding to the receptor(s) and intramolecular cleavage are essential for DNT to intoxicate cells, and the 54 amino-acid binding domain encompasses the cleavage site, however, it is unclear whether these two events are related. In this study, we could narrow down the cell-binding domain to the N-terminal amino acids 2-30. The region does not contain the furin-recognition site, indicating that the cell binding and the intramolecular cleavage are independent events.


Subject(s)
Amino Acids/metabolism , Bordetella/metabolism , Peptides/metabolism , Transglutaminases/metabolism , Virulence Factors, Bordetella/metabolism , Amino Acid Sequence , Amino Acids/chemistry , Animals , Binding Sites , Bordetella/genetics , COS Cells , Cell Line , Chlorocebus aethiops , Genes, Reporter/genetics , Humans , Immunoglobulin G/genetics , Immunoglobulin G/metabolism , Luciferases/metabolism , Mice , Molecular Sequence Data , Peptides/chemistry , Protein Binding , Protein Structure, Secondary , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Transglutaminases/chemistry , Transglutaminases/genetics , Virulence Factors, Bordetella/chemistry , Virulence Factors, Bordetella/genetics , rho GTP-Binding Proteins/metabolism
4.
J Food Sci ; 74(8): M461-6, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19799674

ABSTRACT

To reduce the amounts of verocytotoxin (VT) produced by Escherichia coli O157:H7, various spices were screened for their ability to suppress VT production. Extracts of these spices were prepared with 70% ethyl alcohol. When E. coli O157:H7 cells were grown to the stationary phase at 37 degrees C in Luria-Bertani medium supplemented with 0.02% allspice extract, the production of both VT1 and VT2 was significantly reduced. Neither growth inhibition nor a delay in the lag phase was observed when the cells were cultured in the presence of 0.02% allspice extract. An active component of the allspice extract was purified by HPLC and was identified as eugenol. When we examined the suppressive effect of eugenol on VT production by E. coli O157:H7, the amounts of both intracellular and extracellular VTs were found to decrease with an increase in eugenol concentration. Our results suggest that eugenol is useful for reducing the virulence of E. coli O157:H7.


Subject(s)
Anti-Infective Agents/pharmacology , Escherichia coli O157/drug effects , Eugenol/pharmacology , Food Additives/pharmacology , Plant Extracts/pharmacology , Shiga Toxins/biosynthesis , Spices , Anti-Infective Agents/analysis , Anti-Infective Agents/chemistry , Anti-Infective Agents/isolation & purification , Colony Count, Microbial , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical , Escherichia coli O157/growth & development , Escherichia coli O157/isolation & purification , Escherichia coli O157/metabolism , Eugenol/analysis , Eugenol/isolation & purification , Feces/microbiology , Food Additives/analysis , Food Additives/isolation & purification , Humans , Latex Fixation Tests , Pimenta/chemistry , Plant Extracts/chemistry , Shiga Toxin 1/antagonists & inhibitors , Shiga Toxin 1/biosynthesis , Shiga Toxin 2/antagonists & inhibitors , Shiga Toxin 2/biosynthesis , Shiga Toxins/antagonists & inhibitors
SELECTION OF CITATIONS
SEARCH DETAIL
...