The objective of this study was to assess the association between previous antibiotic use, particularly long-term prophylaxis, and the occurrence of subsequent resistant infections in children with ...index infections due to extended-spectrum-cephalosporin-resistant
We also investigated the concordance of the index and subsequent isolates. Extended-spectrum-cephalosporin-resistant
and
spp. isolated from normally sterile sites of patients aged <22 years were collected along with associated clinical data from four freestanding pediatric centers. Subsequent isolates were categorized as concordant if the species, resistance determinants, and
(
) or
(
) type were identical to those of the index isolate. In total, 323 patients had 396 resistant isolates; 45 (14%) patients had ≥1 subsequent resistant infection, totaling 73 subsequent resistant isolates. The median time between the index and first subsequent infections was 123 (interquartile range, 43 to 225) days. In multivariable Cox proportional hazards analyses, patients were 2.07 times as likely to have a subsequent resistant infection (95% confidence interval, 1.11 to 3.87) if they received prophylaxis in the 30 days prior to the index infection. In 26 (58%) patients, all subsequent isolates were concordant with their index isolate, and 7 (16%) additional patients had at least 1 concordant subsequent isolate. In 12 of 17 (71%) patients with
sequence type 131 (ST131)-associated type 40-30, all subsequent isolates were concordant. Subsequent extended-spectrum-cephalosporin-resistant infections are relatively frequent and are most commonly due to bacterial strains concordant with the index isolate. Further study is needed to assess the role prophylaxis plays in these resistant infections.
To investigate the relation between
Helicobacter pylori infection and the clinical features of idiopathic thrombocytopenic purpura (ITP), and to examine the effects of
H. pylori eradication on ...platelet counts.
A
13C urea breath test for
H. pylori infection was performed in a cohort of 137 consecutive patients with ITP. Patients who tested positive received standard eradication therapy if their platelet count was <50 × 10
9/L or if they had symptoms of dyspepsia.
H. pylori infection was detected in 64 patients (47%), and was not associated with dyspepsia or other clinical or laboratory features. Eradication therapy was successfully administered to 52 patients. Platelet responses were observed in 17 (33%) of these patients, which lasted for more than 1 year in 11 patients. Duration of ITP was shorter among responders than nonresponders. Only one response was observed among patients with severe thrombocytopenia (platelet count <30 × 10
9/L).
The prevalence of
H. pylori infection in patients with ITP is similar to that found in the general population. Infection is not associated with distinctive features of the disease.
H. pylori eradication may improve the platelet counts in adults in whom the ITP is of recent onset and in those with less severe degrees of thrombocytopenia, but was not effective in patients with chronic severe ITP.
Honey bees, Apis mellifera, are a globally significant pollinator species and are currently in decline, with losses attributed to an array of interacting environmental stressors. Extremely low ...frequency electromagnetic fields (ELF EMFs) are a lesser-known abiotic environmental factor that are emitted from a variety of anthropogenic sources, including power lines, and have recently been shown to have a significant impact on the cognitive abilities and behaviour of honey bees. Here we have investigated the effects of field-realistic levels of ELF EMFs on aversive learning and aggression levels, which are critical factors for bees to maintain colony strength. Bees were exposed for 17 h to 100 μT or 1000 μT ELF EMFs, or a sham control. A sting extension response (SER) assay was conducted to determine the effects of ELF EMFs on aversive learning, while an intruder assay was conducted to determine the effects of ELF EMFs on aggression levels. Exposure to both 100 μT and 1000 μT ELF EMF reduced aversive learning performance by over 20%. Exposure to 100 μT ELF EMFs also increased aggression scores by 60%, in response to intruder bees from foreign hives. These results indicate that short-term exposure to ELF EMFs, at levels that could be encountered in bee hives placed under power lines, reduced aversive learning and increased aggression levels. These behavioural changes could have wider ecological implications in terms of the ability of bees to interact with, and respond appropriately to, threats and negative environmental stimuli.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Quantitation of apoptotic cell death in vivo has become an important issue for patients with acute leukemia. We describe herein a new analytical method, based on infrared (IR) spectroscopy, to ...estimate the percentage of apoptotic leukemic cells in two different cell lines (CEM and K562), induced with etoposide (VP-16). As the percentage of apoptosis increases, the protein structure shifts from dominantly beta-sheet to unordered (random coil), the overall lipid content increases and the amount of detectable DNA decreases. These changes can be directly related to the percentage of apoptosis as determined by two standard reference methods: flow cytometry and DNA ladder formation. The correlation between the significant IR spectral changes and the percentage of apoptotic leukemia cells in the two cell lines was optimal up to 24 h following etoposide treatment (r = 0.99 for CEM cells and r = 0.96 for K562 cells). Furthermore, IR spectroscopy is able to detect apoptotic changes in these cells already after 4 h treatment with VP-16, compared to flow cytometry which needs 6 h to observe significant changes. Our study suggests that IR spectroscopy may have potential clinical utility for the early, fast and reagent free assessment of chemotherapeutic efficacy in patients with leukemia.
The p53- and Bcl-2-negative leukemic K562 cell line showed resistant to DNA damage-induced Bax activation and apoptosis. The constitutive balanced ratio of Bax/Bcl-XL in K562 mitochondria allowed the ...formation of active Bax and cytochrome c release from mitochondria in the presence of a BH3-only protein, tBid, in a cell-free system. Bax transfection led to Bax undergoing a conformational change, translocation to mitochondria and homo-oligomerization but not apoptosis in the K562 cell line. After treatment with UV light, while Bcl-XL but not Bax translocated to mitochondria in K562, both Bax and Bcl-XL translocated to mitochondria in the Bax stable transfectant K/Bax cells. The increased ratio of Bax/Bcl-XL in K/Bax mitochondria led to an increased conformationally changed Bax, formation of the homo-multimer of Bax-Bax, and a reduced hetero-dimerization of Bax-Bcl-XL. Increased proportion of active Bax was accompanied with increased percentage of apoptosis. We therefore demonstrate that direct increase in the ratio of mitochondrial Bax/Bcl-XL can induce Bax activation in the p53- and Bcl-2-negative leukemic cells. Increased Bcl-XL translocation and failure in Bax translocation from cytosol to mitochondria play important roles in preventing Bax activation.
Background: Procalcitonin (PCT), a precursor of calcitonin, is a recognised marker of bacterial sepsis, and high concentrations correlate with the severity of sepsis. PCT has been proposed as an ...earlier and better diagnostic marker than C reactive protein (CRP) and white cell count (WCC). This comparison has never been reported in the differentiation of meningococcal disease (MCD) in children presenting with a fever and rash. Aim: To determine if PCT might be a useful marker of MCD in children presenting with fever and rash. Methods: PCT, CRP, and WCC were measured on admission in 108 children. Patients were classified into two groups: group I, children with a microbiologically confirmed clinical diagnosis of MCD (n = 64); group II, children with a self limiting illness (n = 44). Median ages were 3.57 (0.07–15.9) versus 1.75 (0.19–14.22) years respectively. Severity of disease in patients with MCD was assessed using the Glasgow Meningococcal Septicaemia Prognostic Score (GMSPS). Results: PCT and CRP values were significantly higher in group I than in group II (median 38.85 v 0.27 ng/ml and 68.35 v 9.25 mg/l; p < 0.0005), but there was no difference in WCC between groups. Sensitivity, specificity, and positive and negative predictive values were higher for PCT than CRP and WCC. In group I, procalcitonin was significantly higher in those with severe disease (GMSPS ≥8). Conclusions: PCT is a more sensitive and specific predictor of MCD than CRP and WCC in children presenting with fever and a rash.
Alzheimer disease (AD) is the most common dementing illness in the elderly, but there is equivocal evidence regarding the frequency of other disorders such as Lewy body disease (LBD), vascular ...dementia (VaD), frontotemporal dementia (FTD), and hippocampal sclerosis (HS). This ambiguity may be related to factors such as the age and gender of subjects with dementia. Therefore, the objective of this study was to calculate the relative frequencies of AD, LBD, VaD, FTD, and HS among 382 subjects with dementia from the State of Florida Brain Bank and to study the effect of age and gender on these frequencies. AD was the most frequent pathologic finding (77%), followed by LBD (26%), VaD (18%), HS (13%), and FTD (5%). Mixed pathology was common: Concomitant AD was present in 66% of LBD patients, 77% of VaD patients, and 66% of HS patients. The relative frequency of VaD increased with age, whereas the relative frequencies of FTD and LBD declined with age. Males were overrepresented among those with LBD, whereas females were overrepresented among AD subjects with onset age over 70 years. These estimates of the a priori probabilities of dementing disorders have implications for clinicians and researchers.
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