Rapid detection of abnormal biological values using point-of-care (POC) testing allows clinicians to promptly initiate therapy; however, there are concerns regarding the reliability of POC ...measurements. We investigated the agreement between the latest generation blood gas analyzer and central laboratory measurements of electrolytes, bicarbonate, hemoglobin, hematocrit, and glucose.
314 paired samples were collected prospectively from 51 critically ill patients. All samples were drawn simultaneously in the morning from an arterial line. BD Vacutainer tubes were analyzed in the central laboratory using Beckman Coulter analyzers (AU 5800 and DxH 800). BD Preset 3 ml heparinized-syringes were analyzed immediately in the ICU using the POC Siemens RAPIDPoint 500 blood gas system. We used CLIA proficiency testing criteria to define acceptable analytical performance and interchangeability.
Biases, limits of agreement (±1.96 SD) and coefficients of correlation were respectively: 1.3 (-2.2 to 4.8 mmol/L, r = 0.936) for sodium; 0.2 (-0.2 to 0.6 mmol/L, r = 0.944) for potassium; -0.9 (-3.7 to 2 mmol/L, r = 0.967) for chloride; 0.8 (-1.9 to 3.4 mmol/L, r = 0.968) for bicarbonate; -11 (-30 to 9 mg/dL, r = 0.972) for glucose; -0.8 (-1.4 to -0.2 g/dL, r = 0.985) for hemoglobin; and -1.1 (-2.9 to 0.7%, r = 0.981) for hematocrit. All differences were below CLIA cut-off values, except for hemoglobin.
Compared to central Laboratory analyzers, the POC Siemens RAPIDPoint 500 blood gas system satisfied the CLIA criteria of interchangeability for all tested parameters, except for hemoglobin. These results are warranted for our own procedures and devices. Bearing these restrictions, we recommend clinicians to initiate an appropriate therapy based on POC testing without awaiting a control measurement.
Natural killer cells, as a major source of interferon-γ, contribute to the amplification of the inflammatory response as well as to mortality during severe sepsis in animal models.
We studied the ...phenotype and functions of circulating NK cells in critically-ill septic patients.
Blood samples were taken <48 hours after admission from 42 ICU patients with severe sepsis (n = 15) or septic shock (n = 14) (Sepsis group), non-septic SIRS (n = 13) (SIRS group), as well as 21 healthy controls. The immuno-phenotype and functions of NK cells were studied by flow cytometry.
The absolute number of peripheral blood CD3-CD56(+) NK cells was similarly reduced in all groups of ICU patients, but with a normal percentage of NK cells. When NK cell cytotoxicity was evaluated with degranulation assays (CD107 expression), no difference was observed between Sepsis patients and healthy controls. Under antibody-dependent cell cytotoxicity (ADCC) conditions, SIRS patients exhibited increased CD107 surface expression on NK cells (62.961.3-70%) compared to healthy controls (43.532.1-53.1%) or Sepsis patients (49.237.3-62.9%) (p = 0.002). Compared to healthy (10.26.3-13.1%), reduced interferon-γ production by NK cells (K562 stimulation) was observed in Sepsis group (6.22.2-9.9%, p<0.01), and especially in patients with septic shock. Conversely, SIRS patients exhibited increased interferon-γ production (42.930.1-54.7%) compared to Sepsis patients (18.411.7-35.7%, p<0.01) or healthy controls (26.819.3-44.9%, p = 0.09) in ADCC condition.
Extensive monitoring of the NK-cell phenotype and function in critically-ill septic patients revealed early decreased NK-cell function with impaired interferon-γ production. These results may aid future NK-based immuno-interventions.
NTC00699868.
Background
Nosocomial infections occurring during extracorporeal membrane oxygenation (ECMO) support have already been reported, but few studied infections directly related to ECMO devices. This ...study aims to evaluate the rate of both colonisations and infections related to ECMO devices at the time of ECMO removal.
Results
We included all consecutive adult patients treated with venovenous ECMO (VV-ECMO) for at least 48 h during a 34-month study. At the time of ECMO removal, blood cultures, swab cultures on insertion cannula site and intravascular cannula extremity cultures were systematically performed. Each ECMO device was classified according to the infectious status into three groups: (1) uninfected/uncolonised ECMO device, (2) ECMO device colonisation and (3) ECMO device infection. Ninety-nine patients underwent 103 VV-ECMO, representing 1472 ECMO days. The ECMO device infection rate was 9.7% (10 events), including 7 ECMO device-related bloodstream infections (6.8%). The ECMO device colonisation rate was 32% (33 events). No difference was observed between the three groups, regarding days of mechanical ventilation, ICU length of stay, ICU mortality and in-hospital mortality. We observed a longer ECMO duration in the ECMO device colonisation group as compared to the uninfected/uncolonised ECMO device group 12 (9–20 days) vs. 5 days (5–16 days), respectively,
p
< 0.05.
Conclusions
At the time of ECMO removal, systematic blood culture and intravascular extremity cannula culture may help to diagnose ECMO device-related infection. We reported a quite low infection rate related to ECMO device. Further studies are needed to evaluate the benefits of systematic strategies of cannula culture at the time of ECMO removal.
Cardiac involvement during systemic lupus erythematosus (SLE) may include the pericardium, myocardium, valvular tissue, and coronary arteries. The aim of this study was to describe the clinical, ...biological, and radiological presentation of lupus myocarditis (LM) as well as the treatment response and longterm outcomes.
We conducted a multicentric retrospective study of LM from January 2000 to May 2014.
Twenty-nine patients (3 men and 26 women) fulfilled the inclusion criteria (median age at the diagnosis of SLE: 30 yrs, range 16-57). Myocarditis was the first sign of SLE in 17/29 cases (58.6%). Troponin was elevated in 20/25 cases. Electrocardiogram results were abnormal in 25/28 cases. Echocardiography revealed low (≤ 45%) left ventricular ejection fraction (LVEF; 19/29, 66%) and pericardium effusion (20/29, 69%). Cardiac magnetic resonance imaging revealed delayed gadolinium enhancement in 9/13 patients (69%). Patients were treated with corticosteroids (n = 28), cyclophosphamide (CYC; n = 16), intravenous immunoglobulins (n = 8), and/or mycophenolate mofetil (n = 2). The median followup was 37 months. One month after the beginning of the treatment, 10/23 patients (43%) who had undergone echocardiography had an LVEF ≥ 55%. At the end of followup, 21/26 patients (81%) exhibited an LVEF ≥ 55%. Three patients died during followup, and 2 died from LM.
LM is a severe manifestation of SLE. It can be the first manifestation of the disease or it can occur during followup, in particular in untreated patients. However, the longterm prognosis is typically positive. Patients with less severe disease exhibited good LVEF recovery without CYC.
The Role of Natural Killer Cells in Sepsis Chiche, Laurent; Forel, Jean-Marie; Thomas, Guillemette ...
BioMed research international,
01/2011, Letnik:
2011, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Severe sepsis and septic shock are still deadly conditions urging to develop novel therapies. A better understanding of the complex modifications of the immune system of septic patients is needed for ...the development of innovative immunointerventions. Natural killer (NK) cells are characterized as CD3−NKp46+CD56+ cells that can be cytotoxic and/or produce high amounts of cytokines such as IFN-γ. NK cells are also engaged in crosstalks with other immune cells, such as dendritic cells, macrophages, and neutrophils. During the early stage of septic shock, NK cells may play a key role in the promotion of the systemic inflammation, as suggested in mice models. Alternatively, at a later stage, NK cells-acquired dysfunction could favor nosocomial infections and mortality. Standardized biological tools defining patients' NK cell status during the different stages of sepsis are mandatory to guide potential immuno-interventions. Herein, we review the potential role of NK cells during severe sepsis and septic shock.
Background Health care–associated infections (HAIs) are a major cause of morbidity and mortality in intensive care unit (ICU) patients. Our objective was to evaluate the impact of daily bathing with ...chlorhexidine gluconate (CHG) on the incidence rates of HAIs, with a focus on their causative bacteria, in a French ICU. Methods From March 2012-May 2013, we enrolled 325 patients with at least 1 episode of suspected sepsis in the ICU, during two 6-month periods. The intervention group was subjected daily to skin cleansing with 2% CHG–impregnated cloths, whereas the control group was bathed daily with soap and water. HAI included bloodstream infections, ventilator-associated pneumonia, and urinary tract infections. Incidence rates corresponded to the number of infections per 1,000 patient days. Results Incidence of HAI was significantly decreased in the intervention group (29 vs 56; P = .01). After adjustment for baseline patient characteristics, the increased risk of HAI in the water and soap group was significant (odds ratio = 1.993; 95% confidence interval CI, 1.132-3.508; P = .017). The incidence rate of clinical cultures positive for gram-negative bacteria, including Enterobacteriaceae and nonfermenting bacilli, decreased in the intervention group (risk ratio = 0.588; 95% CI, 0.346-0.978; P = .04). Conclusions CHG daily cleansing reduced the incidence rate of HAI caused by gram-negative bacteria, highlighting the role of the transient gram-negative bacteria skin colonization in the pathogenesis of HAI.
MCC/eisosomes are membrane microdomains that have been proposed to participate in the plasma membrane function in particular by regulating the homeostasis of lipids, promoting the recruitment of ...specific proteins and acting as provider of membrane reservoirs.
Here we showed that several potential MCC/eisosomal protein encoding genes in the necrotrophic fungus A. brassicicola were overexpressed when germinated spores were exposed to antimicrobial defence compounds, osmotic and hydric stresses, which are major constraints encountered by the fungus during the plant colonization process. Mutants deficient for key MCC/eisosome components did not exhibit any enhanced susceptibility to phytoalexins and to applied stress conditions compared to the reference strain, except for a slight hypersensitivity of the ∆∆abpil1a-abpil1b strain to 2 M sorbitol. Depending on the considered mutants, we showed that the leaf and silique colonization processes were impaired by comparison to the wild-type, and assumed that these defects in aggressiveness were probably caused by a reduced appressorium formation rate.
This is the first study on the role of MCC/eisosomes in the pathogenic process of a plant pathogenic fungus. A link between these membrane domains and the fungus ability to form functional penetration structures was shown, providing new potential directions for plant disease control strategies.
Filamentous fungi such as Aspergillus niger have a high capacity secretory system and are therefore widely exploited for the industrial production of native and heterologous proteins. However, in ...most cases the yields of non-fungal proteins are significantly lower than those obtained for fungal proteins. One well-studied bottleneck appears to be the result of mis-folding of heterologous proteins in the ER during early stages of secretion, with related stress responses in the host, including the unfolded protein response (UPR). This study aims at uncovering transcriptional and translational responses occurring in A. niger exposed to secretion stress.
A genome-wide transcriptional analysis of protein secretion-related stress responses was determined using Affymetrix DNA GeneChips and independent verification for selected genes. Endoplasmic reticulum (ER)-associated stress was induced either by chemical treatment of the wild-type cells with dithiothreitol (DTT) or tunicamycin, or by expressing a human protein, tissue plasminogen activator (t-PA). All of these treatments triggered the UPR, as shown by the expression levels of several well-known UPR target genes. The predicted proteins encoded by most of the up-regulated genes function as part of the secretory system including chaperones, foldases, glycosylation enzymes, vesicle transport proteins, and ER-associated degradation proteins. Several genes were down-regulated under stress conditions and these included several genes that encode secreted enzymes. Moreover, translational regulation under ER stress was investigated by polysomal fractionation. This analysis confirmed the post-transcriptional control of hacA expression and highlighted that differential translation also occurs during ER stress, in particular for some genes encoding secreted proteins or proteins involved in ribosomal biogenesis and assembly.
This is first genome-wide analysis of both transcriptional and translational events following protein secretion stress. Insight has been gained into the molecular basis of protein secretion and secretion-related stress in an effective protein-secreting fungus, and provides an opportunity to identify target genes for manipulation in strain improvement strategies.
Background
Grey mould caused by
Botrytis cinerea
Pers. (teleomorph
Botryotinia fuckeliana
(de Bary) Whetzel) is one of the most destructive fungal diseases of Mediterranean crops. In Algeria, few ...studies have been made on the economic impact of this disease. Nevertheless, it is practically present in all tomato and strawberry greenhouses, as well as in prospected vineyards in the north and south of the country. The complexity of chemical control of this disease has led to search for
Trichoderma
strains that are effective in biological control.
Results
Fifteen isolates of
Trichoderma
spp. were obtained from vigorous and healthy plants (tomatoes, strawberries, and vines) rhizosphere, and from a commercial bio-compost (Bio-composte®), then identified as
T. afroharzianum
(four isolates),
T. gamsii
(four isolates),
T. longibrachiatum
(three isolates),
T. atroviride
(one isolate),
T. brevicompactum
(one isolate),
T. breve
(one isolate), and
T. lixii
(one isolate) on the basis of DNA sequence analysis of four genes (ITS,
tef1
,
rpb2
, and
acl1
). In vitro biocontrol tests revealed that four Algerian isolates of
Trichoderma
spp. (TAtC11, TGS7, TGS10, and TBS1) had a high antagonistic activity against
B. cinerea
, the mycelial growth has been reduced by 62 to 65% in dual-culture technique, by 62.31 to 64.49% in volatile compounds test, and a high inhibition of germling growth was recorded by TBS1 isolate with 90.68% in Culture filtrates test. Biocontrol tests carried out on tomato plants with
T. brevicompactum
(TBS1),
T. atroviride
(TAtC11), and
T. lixii
(TLiC8) against
B. cinerea
(BCT04) showed that TBS1 inoculation significantly reduced the incidence of disease by 64.43 and 51.35% in preventive and curative treatment, respectively.
Conclusion
The present study revealed the first report of
T. brevicompactum
,
T. breve
, and
T. lixii
in Algeria, and it also contributes to the promotion of the use of native strains of
Trichoderma
in biological control leading to a better preservation of soil microbial diversity.
Glutathione transferases (GSTs) represent an extended family of multifunctional proteins involved in detoxification processes and tolerance to oxidative stress. We thus anticipated that some GSTs ...could play an essential role in the protection of fungal necrotrophs against plant-derived toxic metabolites and reactive oxygen species that accumulate at the host-pathogen interface during infection.
Mining the genome of the necrotrophic Brassica pathogen Alternaria brassicicola for glutathione transferase revealed 23 sequences, 17 of which could be clustered into the main classes previously defined for fungal GSTs and six were 'orphans'. Five isothiocyanate-inducible GSTs from five different classes were more thoroughly investigated. Analysis of their catalytic properties revealed that two GSTs, belonging to the GSTFuA and GTT1 classes, exhibited GSH transferase activity with isothiocyanates (ITC) and peroxidase activity with cumene hydroperoxide, respectively. Mutant deficient for these two GSTs were however neither more susceptible to ITC nor less aggressive than the wild-type parental strain. By contrast mutants deficient for two other GSTs, belonging to the Ure2pB and GSTO classes, were distinguished by their hyper-susceptibility to ITC and low aggressiveness against Brassica oleracea. In particular AbGSTO1 could participate in cell tolerance to ITC due to its glutathione-dependent thioltransferase activity. The fifth ITC-inducible GST belonged to the MAPEG class and although it was not possible to produce the soluble active form of this protein in a bacterial expression system, the corresponding deficient mutant failed to develop normal symptoms on host plant tissues.
Among the five ITC-inducible GSTs analyzed in this study, three were found essential for full aggressiveness of A. brassicicola on host plant. This, to our knowledge is the first evidence that GSTs might be essential virulence factors for fungal necrotrophs.
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