925 resultados para Antibiotic sensitivity test


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This study was aimed to correlate the results of relative germination from in vitro tests by trifloxystrobin with those of qPCR on a wide range of V. inaequalis populations and monoconidial isolates. Samples were collected in Italian and Turkish distinct locations from orchards with different scab management. In this study, an allele-specific qPCR with primer sets designed was successfully developed to quantitatively determine the frequency of QoI-resistant allele G143A in populations and monoconidial isolates of V. inaequalis. qPCR followed a similar pattern to that obtained using in vitro conidial germination test in very sensitive and very resistant populations. However, the variability between two test results was observed in hetereogenous populations. Therefore, the results of correlations between in vitro and qPCR showed a positive but not very high correlation for Venturia inaequalis populations (R2=0.70). On the contrary, this correlation between two assessment methods was very high for monoconidial isolates (R2=0.92). Results obtained in quantitative PCR and from traditional spore germination assay differed for the same fungal population and in some cases, it is difficult to assess the resistance in the field by only qPCR. It was concluded that it is not always possible to correlate the frequency of detection of the mutation with biological assessment. In such situations, monitoring by molecular techniques must be supported by standard in vitro resistance assessments and observation of field performance in order to have correct conclusions.

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In case of violation of CPT- and Lorentz Symmetry, the minimal Standard Model Extension (SME) of Kostelecky and coworkers predicts sidereal modulations of atomic transition frequencies as the Earth rotates relative to a Lorentz-violating background field. One method to search for these modulations is the so-called clock-comparison experiment, where the frequencies of co-located clocks are compared as they rotate with respect to the fixed stars. In this work an experiment is presented where polarized 3He and 129Xe gas samples in a glass cell serve as clocks, whose nuclear spin precession frequencies are detected with the help of highly sensitive SQUID sensors inside a magnetically shielded room. The unique feature of this experiment is the fact that the spins are precessing freely, with transverse relaxation times of up to 4.4 h for 129Xe and 14.1 h for 3He. To be sensitive to Lorentz-violating effects, the influence of external magnetic fields is canceled via the weighted difference of the 3He and 129Xe frequencies or phases. The Lorentz-violating SME parameters for the neutron are determined out of a fit on the phase difference data of 7 spin precession measurements of 12 to 16 hours length. The result of the fit gives an upper limit for the equatorial component of the neutron parameter b_n of 3.7×10^(−32) GeV at the 95% confidence level. This value is not limited by the signal-to-noise ratio, but by the strong correlations between the fit parameters. To reduce the correlations and therewith improve the sensitivity of future experiments, it will be necessary to change the time structure of the weighted phase difference, which can be realized by increasing the 129Xe relaxation time.

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Die elektrische Ladung des Neutrons ist eng mit der Frage nach der Existenz der Ladungsquantisierung verknüpft: Sollte das Neutron eine Ladung tragen, kann die Ladung nicht in Einheiten der Elementarladung e quantisiert sein.rnrnIm Rahmen der Elektrodynamik und des minimalen Standardmodells ist die Quantisierung der Ladung nicht enthalten. Eine mögliche Neutronenladung würde ihnen also nicht widersprechen. Allerdings geht sie aus den Weiterentwicklungen dieser Modelle hervor. Die sogenannten Grand Unified Theories sagen die Möglichkeit des Protonenzerfalls vorher. Dieser ist nur möglich, wenn die Ladung quantisiert ist.rnrnDurch die Messung einer elektrischen Ladung des Neutrons können die verschiedenen Theorien überprüft werden.rnrnIm Rahmen dieser Arbeit wurde eine Apparatur entwickelt, mit der die elektrische Ladung des Neutrons gemessen werden kann. Als Grundlage diente das Prinzip einer Messung von 1988. Mit einem flüssigen Neutronenspiegel aus Fomblin ist es zum ersten mal überhaupt gelungen, einen flüssigen Spiegel für Neutronen einzusetzen. Durch diese und andere Verbesserungen konnte die Sensitivität der Apparatur um einen Faktor 5 im Vergleich zum Experimentrnvon 1988 verbessert werden. Eine mögliche Ladung des Neutrons kann mit δq_n = 2,15·10^(−20)·e/√day gemessen werden. rnrnDie Messung der elektrischen Ladung soll im Winter 2014 durchgeführt werden. Bis dahin soll die Präzision aufrnδq_n = 1,4·10^(−21)·e/√day erhöht werden.

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Für das Vermögen der Atmosphäre sich selbst zu reinigen spielen Stickstoffmonoxid (NO) und Stickstoffdioxid (NO2) eine bedeutende Rolle. Diese Spurengase bestimmen die photochemische Produktion von Ozon (O3) und beeinflussen das Vorkommen von Hydroxyl- (OH) und Nitrat-Radikalen (NO3). Wenn tagsüber ausreichend Solarstrahlung und Ozon vorherrschen, stehen NO und NO2 in einem schnellen photochemischen Gleichgewicht, dem „Photostationären Gleichgewichtszustand“ (engl.: photostationary state). Die Summe von NO und NO2 wird deshalb als NOx zusammengefasst. Vorhergehende Studien zum photostationären Gleichgewichtszustand von NOx umfassen Messungen an unterschiedlichsten Orten, angefangen bei Städten (geprägt von starken Luftverschmutzungen), bis hin zu abgeschiedenen Regionen (geprägt von geringeren Luftverschmutzungen). Während der photochemische Kreislauf von NO und NO2 unter Bedingungen erhöhter NOx-Konzentrationen grundlegend verstanden ist, gibt es in ländlicheren und entlegenen Regionen, welche geprägt sind von niedrigeren NOx-Konzetrationen, signifikante Lücken im Verständnis der zugrundeliegenden Zyklierungsprozesse. Diese Lücken könnten durch messtechnische NO2-Interferenzen bedingt sein - insbesondere bei indirekten Nachweismethoden, welche von Artefakten beeinflusst sein können. Bei sehr niedrigen NOx-Konzentrationen und wenn messtechnische NO2-Interferenzen ausgeschlossen werden können, wird häufig geschlussfolgert, dass diese Verständnislücken mit der Existenz eines „unbekannten Oxidationsmittels“ (engl.: unknown oxidant) verknüpft ist. Im Rahmen dieser Arbeit wird der photostationäre Gleichgewichtszustand von NOx analysiert, mit dem Ziel die potenzielle Existenz bislang unbekannter Prozesse zu untersuchen. Ein Gasanalysator für die direkte Messung von atmosphärischem NO¬2 mittels laserinduzierter Fluoreszenzmesstechnik (engl. LIF – laser induced fluorescence), GANDALF, wurde neu entwickelt und während der Messkampagne PARADE 2011 erstmals für Feldmessungen eingesetzt. Die Messungen im Rahmen von PARADE wurden im Sommer 2011 in einem ländlich geprägten Gebiet in Deutschland durchgeführt. Umfangreiche NO2-Messungen unter Verwendung unterschiedlicher Messtechniken (DOAS, CLD und CRD) ermöglichten einen ausführlichen und erfolgreichen Vergleich von GANDALF mit den übrigen NO2-Messtechniken. Weitere relevante Spurengase und meteorologische Parameter wurden gemessen, um den photostationären Zustand von NOx, basierend auf den NO2-Messungen mit GANDALF in dieser Umgebung zu untersuchen. Während PARADE wurden moderate NOx Mischungsverhältnisse an der Messstelle beobachtet (10^2 - 10^4 pptv). Mischungsverhältnisse biogener flüchtige Kohlenwasserstoffverbindungen (BVOC, engl.: biogenic volatile organic compounds) aus dem umgebenden Wald (hauptsächlich Nadelwald) lagen in der Größenordnung 10^2 pptv vor. Die Charakteristiken des photostationären Gleichgewichtszustandes von NOx bei niedrigen NOx-Mischungsverhältnissen (10 - 10^3 pptv) wurde für eine weitere Messstelle in einem borealen Waldgebiet während der Messkampagne HUMPPA-COPEC 2010 untersucht. HUMPPA–COPEC–2010 wurde im Sommer 2010 in der SMEARII-Station in Hyytiälä, Süd-Finnland, durchgeführt. Die charakteristischen Eigenschaften des photostationären Gleichgewichtszustandes von NOx in den beiden Waldgebieten werden in dieser Arbeit verglichen. Des Weiteren ermöglicht der umfangreiche Datensatz - dieser beinhaltet Messungen von relevanten Spurengasen für die Radikalchemie (OH, HO2), sowie der totalen OH-Reaktivität – das aktuelle Verständnis bezüglich der NOx-Photochemie unter Verwendung von einem Boxmodell, in welches die gemessenen Daten als Randbedingungen eingehen, zu überprüfen und zu verbessern. Während NOx-Konzentrationen in HUMPPA-COPEC 2010 niedriger sind, im Vergleich zu PARADE 2011 und BVOC-Konzentrationen höher, sind die Zyklierungsprozesse von NO und NO2 in beiden Fällen grundlegend verstanden. Die Analyse des photostationären Gleichgewichtszustandes von NOx für die beiden stark unterschiedlichen Messstandorte zeigt auf, dass potenziell unbekannte Prozesse in keinem der beiden Fälle vorhanden sind. Die aktuelle Darstellung der NOx-Chemie wurde für HUMPPA-COPEC 2010 unter Verwendung des chemischen Mechanismus MIM3* simuliert. Die Ergebnisse der Simulation sind konsistent mit den Berechnungen basierend auf dem photostationären Gleichgewichtszustand von NOx.

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Recent studies have shown that the nociceptive withdrawal reflex threshold (NWR-T) and the electrical pain threshold (EP-T) are reliable measures in pain-free populations. However, it is necessary to investigate the reliability of these measures in patients with chronic pain in order to translate these techniques from laboratory to clinic. The aims of this study were to determine the test-retest reliability of the NWR-T and EP-T after single and repeated (temporal summation) electrical stimulation in a group of patients with chronic low back pain, and to investigate the association between the NWR-T and the EP-T. To this end, 25 patients with chronic pain participated in three identical sessions, separated by 1 week in average, in which the NWR-T and the EP-T to single and repeated stimulation were measured. Test-retest reliability was assessed using intra-class correlation coefficient (ICC), coefficient of variation (CV), and Bland-Altman analysis. The association between the thresholds was assessed using the coefficient of determination (r (2)). The results showed good-to-excellent reliability for both NWR-T and EP-T in all cases, with average ICC values ranging 0.76-0.90 and average CV values ranging 12.0-17.7%. The association between thresholds was better after repeated stimulation than after single stimulation, with average r (2) values of 0.83 and 0.56, respectively. In conclusion, the NWR-T and the EP-T are reliable assessment tools for assessing the sensitivity of spinal nociceptive pathways in patients with chronic pain.

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The use of antibiotics is highest in primary care and directly associated with antibiotic resistance in the community. We assessed regional variations in antibiotic use in primary care in Switzerland and explored prescription patterns in relation to the use of point of care tests. Defined daily doses of antibiotics per 1000 inhabitants (DDD(1000pd) ) were calculated for the year 2007 from reimbursement data of the largest Swiss health insurer, based on the anatomic therapeutic chemical classification and the DDD methodology recommended by WHO. We present ecological associations by use of descriptive and regression analysis. We analysed data from 1 067 934 adults, representing 17.1% of the Swiss population. The rate of outpatient antibiotic prescriptions in the entire population was 8.5 DDD(1000pd) , and varied between 7.28 and 11.33 DDD(1000pd) for northwest Switzerland and the Lake Geneva region. DDD(1000pd) for the three most prescribed antibiotics were 2.90 for amoxicillin and amoxicillin-clavulanate, 1.77 for fluoroquinolones, and 1.34 for macrolides. Regions with higher DDD(1000pd) showed higher seasonal variability in antibiotic use and lower use of all point of care tests. In regression analysis for each class of antibiotics, the use of any point of care test was consistently associated with fewer antibiotic prescriptions. Prescription rates of primary care physicians showed variations between Swiss regions and were lower in northwest Switzerland and in physicians using point of care tests. Ecological studies are prone to bias and whether point of care tests reduce antibiotic use has to be investigated in pragmatic primary care trials.

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PURPOSE: The purpose of our study was to retrospectively evaluate the specificity, sensitivity and accuracy of computed tomography (CT), digital radiography (DR) and low-dose linear slit digital radiography (LSDR, Lodox(®)) in the detection of internal cocaine containers. METHODS: Institutional review board approval was obtained. The study collectively consisted of 83 patients (76 males, 7 females, 16-45 years) suspected of having incorporated cocaine drug containers. All underwent radiological imaging; a total of 135 exams were performed: nCT=35, nDR=70, nLSDR=30. An overall calculation of all "drug mules" and a specific evaluation of body packers, pushers and stuffers were performed. The gold standard was stool examination in a dedicated holding cell equipped with a drug toilet. RESULTS: There were 54 drug mules identified in this study. CT of all drug carriers showed the highest diagnostic accuracy 97.1%, sensitivity 100% and specificity 94.1%. DR in all cases was 71.4% accurate, 58.3% sensitive and 85.3% specific. LSDR of all patients with internal cocaine was 60% accurate, 57.9% sensitive and 63.4% specific. CONCLUSIONS: CT was the most accurate test studied. Therefore, the detection of internal cocaine drug packs should be performed by CT, rather than by conventional X-ray, in order to apply the most sensitive exam in the medico-legal investigation of suspected drug carriers. Nevertheless, the higher radiation applied by CT than by DR or LSDR needs to be considered. Future studies should include evaluation of low dose CT protocols in order to address germane issues and to reduce dosage.

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Background Urinary tract infections (UTI) are frequent in outpatients. Fast pathogen identification is mandatory for shortening the time of discomfort and preventing serious complications. Urine culture needs up to 48 hours until pathogen identification. Consequently, the initial antibiotic regimen is empirical. Aim To evaluate the feasibility of qualitative urine pathogen identification by a commercially available real-time PCR blood pathogen test (SeptiFast®) and to compare the results with dipslide and microbiological culture. Design of study Pilot study with prospectively collected urine samples. Setting University hospital. Methods 82 prospectively collected urine samples from 81 patients with suspected UTI were included. Dipslide urine culture was followed by microbiological pathogen identification in dipslide positive samples. In parallel, qualitative DNA based pathogen identification (SeptiFast®) was performed in all samples. Results 61 samples were SeptiFast® positive, whereas 67 samples were dipslide culture positive. The inter-methodological concordance of positive and negative findings in the gram+, gram- and fungi sector was 371/410 (90%), 477/492 (97%) and 238/246 (97%), respectively. Sensitivity and specificity of the SeptiFast® test for the detection of an infection was 0.82 and 0.60, respectively. SeptiFast® pathogen identifications were available at least 43 hours prior to culture results. Conclusion The SeptiFast® platform identified bacterial DNA in urine specimens considerably faster compared to conventional culture. For UTI diagnosis sensitivity and specificity is limited by its present qualitative setup which does not allow pathogen quantification. Future quantitative assays may hold promise for PCR based UTI pathogen identification as a supplementation of conventional culture methods.

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Fluorescence microlymphography (FML) is used to visualize the lymphatic capillaries. A maximum spread of the fluorescence dye of ≥ 12 mm has been suggested for the diagnosis of lymphedema. However, data on sensitivity and specificity are lacking. The aim of this study was to investigate the accuracy of FML for diagnosing lymphedema in patients with leg swelling. Patients with lower extremity swelling were clinically assessed and separated into lymphedema and non-lymphatic edema groups. FML was studied in all affected legs and the maximum spread of lymphatic capillaries was measured. Test accuracy and receiver operator characteristic (ROC) analysis was performed to assess possible threshold values that predict lymphedema. Between March 2008 and August 2011 a total of 171 patients (184 legs) with a median age of 43.5 (IQR 24, 54) years were assessed. Of those, 94 (51.1%) legs were diagnosed with lymphedema. The sensitivity, specificity, positive and negative likelihood ratio and positive and negative predictive value were 87%, 64%, 2.45, 0.20, 72% and 83% for the 12-mm cut-off level and 79%, 83%, 4.72, 0.26, 83% and 79% for the 14-mm cut-off level, respectively. The area under the ROC curve was 0.82 (95% CI: 0.76, 0.88). Sensitivity was higher in the secondary versus primary lymphedema (95.0% vs 74.3%, p = 0.045). No major adverse events were observed. In conclusion, FML is a simple and safe technique for detecting lymphedema in patients with leg swelling. A cut-off level of ≥ 14-mm maximum spread has a high sensitivity and high specificity of detecting lymphedema and should be chosen.

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REASONS FOR PERFORMING STUDY: Insect bite hypersensitivity (IBH) is an IgE-mediated allergic dermatitis caused by bites of Culicoides and Simulium species, and improved means of diagnosis are required. OBJECTIVES: The cellular antigen simulation test (CAST) with C. nubeculosus and S. vittatum extracts was assessed in a population of IBH-affected and healthy horses. Variations in test results over a one year period and possible cross-reactivity between different insect extracts was studied. METHODS: A total of 314 mature horses were studied using the CAST. Influence of severity of clinical signs, gender and age were evaluated, and 32 horses were tested repeatedly over one year. The kappa reliability test was used to assess agreement of the test results with different insect extracts. RESULTS: Horses with IBH had significantly higher sLT release than controls with C. nubeculosus and S. vittatum. The highest diagnostic sensitivity and specificity levels were attained when using adult C. nubeculosus extracts with the CAST (78% and 97%, respectively), suggesting that most horses with IBH are sensitised against Culicoides allergens. A proportion of IBH-affected horses was found to be sensitised to allergens of Simulium spp. in addition to those of C. nubeculosus. The CAST with C. nubeculosus had positive and negative predictive values > or = 80% for a true prevalence of IBH of 12-52%. In the follow-up study, the proportion of IBH-affected horses with a positive test result ranged from 90% in November to 68% in March. Severity of clinical signs or age did not influence test results significantly. However, IBH-affected males achieved significantly more positive test results than IBH-affected females. CONCLUSIONS: The CAST with adult C. nubeculosus has high specificity and good sensitivity for diagnosis of IBH. Horses with IBH are mainly sensitised to Culicoides allergens, and some horses are additionally also sensitised to allergens in Simulium spp. POTENTIAL RELEVANCE: The CAST is likely to be a useful test for diagnosis of IBH, even allowing the identification of IBH-affected but asymptomatic horses. This test may also help in further characterisation of allergens involved in this condition.

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Vaccines with limited ability to prevent HIV infection may positively impact the HIV/AIDS pandemic by preventing secondary transmission and disease in vaccine recipients who become infected. To evaluate the impact of vaccination on secondary transmission and disease, efficacy trials assess vaccine effects on HIV viral load and other surrogate endpoints measured after infection. A standard test that compares the distribution of viral load between the infected subgroups of vaccine and placebo recipients does not assess a causal effect of vaccine, because the comparison groups are selected after randomization. To address this problem, we formulate clinically relevant causal estimands using the principal stratification framework developed by Frangakis and Rubin (2002), and propose a class of logistic selection bias models whose members identify the estimands. Given a selection model in the class, procedures are developed for testing and estimation of the causal effect of vaccination on viral load in the principal stratum of subjects who would be infected regardless of randomization assignment. We show how the procedures can be used for a sensitivity analysis that quantifies how the causal effect of vaccination varies with the presumed magnitude of selection bias.

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The purpose of this study was to acquire information about the effect of an antibacterial and biodegradable poly-L-lactide (PLLA) coated titanium plate osteosynthesis on local infection resistance. For our in vitro and in vivo experiments, we used six-hole AO DC minifragment titanium plates. The implants were coated with biodegradable, semiamorphous PLLA (coating about 30 microm thick). This acted as a carrier substance to which either antibiotics or antiseptics were added. The antibiotic we applied was a combination of Rifampicin and fusidic acid; the antiseptic was a combination of Octenidin and Irgasan. This produced the following groups: Group I: six-hole AO DC minifragment titanium plate without PLLA; Group II: six-hole AO DC minifragment titanium plate with PLLA without antibiotics/antiseptics; Group III: six-hole AO DC minifragment titanium plate with PLLA + 3% Rifampicin and 7% fusidic acid; Group IV: six-hole AO DC minifragment titanium plate with PLLA + 2% Octenidin and 8% Irgasan. In vitro, we investigated the degradation and the release of the PLLA coating over a period of 6 weeks, the bactericidal efficacy of antibiotics/antiseptics after their release from the coating and the bacterial adhesion of Staphylococcus aureus to the implants. In vivo, we compared the infection rates in white New Zealand rabbits after titanium plate osteosynthesis of the tibia with or without antibacterial coating after local percutaneous bacterial inoculations at different concentrations (2 x 10(5)-2 x 10(8)): The plate, the contaminated soft tissues and the underlying bone were removed under sterile conditions after 28 days and quantitatively evaluated for bacterial growth. A stepwise experimental design with an "up-and-down" dosage technique was used to adjust the bacterial challenge in the area of the ID50 (50% infection dose). Statistical evaluation of the differences between the infection rates of both groups was performed using the two-sided Fisher exact test (p < 0.05). Over a period of 6 weeks, a continuous degradation of the PLLA coating of 13%, on average, was seen in vitro in 0.9% NaCl solution. The elution tests on titanium implants with antibiotic or antiseptic coatings produced average release values of 60% of the incorporated antibiotic or 62% of the incorporated antiseptic within the first 60 min. This was followed by a much slower, but nevertheless continuous, release of the incorporated antibiotic and antiseptic over days and weeks. At the end of the test period of 42 days, 20% of the incorporated antibiotic and 15% of the incorporated antiseptic had not yet been released from the coating. The antibacterial effect of the antibiotic/antiseptic is not lost by integrating it into the PLLA coating. The overall infection rate in the in vivo investigation was 50%. For Groups I and II the infection rate was both 83% (10 of 12 animals). In Groups III and IV with antibacterial coating, the infection rate was both 17% (2 of 12 animals). The ID50 in the antibacterial coated Groups III and IV was recorded as 1 x 10(8) CFU, whereas the ID50 values in the Groups I and II without antibacterial coating were a hundred times lower at 1 x 10(6) CFU, respectively. The difference between the groups with and without antibacterial coating was statistically significant (p = 0.033). Using an antibacterial biodegradable PLLA coating on titanium plates, a significant reduction of infection rate in an in vitro and in vivo investigation could be demonstrated. For the first time, to our knowledge, we were able to show, under standardized and reproducible conditions, that an antiseptic coating leads to the same reduction in infection rate as an antibiotic coating. Taking the problem of antibiotic-induced bacterial resistance into consideration, we thus regard the antiseptic coating, which shows the same level of effectiveness, as advantageous.

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Background: A growing body of literature suggests that caregiving burden is associated with impaired immune system functioning, which may contribute to elevated morbidity and mortality risk among dementia caregivers. However, potential mechanisms linking these relationships are not well understood. The purpose of this study was to investigate whether stress-related experience of depressive symptoms and reductions in personal mastery were related to alterations in ss2-adrenergic receptor sensitivity.Methods: Spousal Alzheimer's caregivers (N = 106) completed measures assessing the extent to which they felt overloaded by their caregiving responsibilities, experienced depressive symptoms, and believed their life circumstances were under their control. We hypothesized that caregivers reporting elevated stress would report increased depressive symptoms and reduced mastery, which in turn would be associated with reduced ss2- adrenergic receptor sensitivity on peripheral blood mononuclear cells (PBMC), as assessed by in vitro isoproterenol stimulation.Results: Regression analyses indicated that overload was negatively associated with mastery (beta = -0.36, p = 0.001) and receptor sensitivity (beta = -0.24, p = 0.030), whereas mastery was positively associated with receptor sensitivity (beta = 0.29, p = 0.005). Finally, the relationship between overload and receptor sensitivity diminshed upon simultaneous entry of mastery. Sobel's test confirmed that mastery significantly mediated some of the relationship between overload and receptor sensitivity (z = -2.02, p = 0.044).Conclusions: These results suggest that a reduced sense of mastery may help explain the association between caregiving burden and reduced immune cell ss2-receptor sensitivity.

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Although the diagnosis of Gitelman syndrome (GS) and Bartter syndrome (BS) is now feasible by genetic analysis, implementation of genetic testing for these disorders is still hampered by several difficulties, including large gene dimensions, lack of hot-spot mutations, heavy workup time, and costs. This study evaluated in a cohort of patients with genetically proven GS or BS diagnostic sensibility and specificity of a diuretic test with oral hydrochlorothiazide (HCT test). Forty-one patients with GS (22 adults, aged 25 to 57; 19 children-adolescents, aged 7 to 17) and seven patients with BS (five type I, two type III) were studied; three patients with "pseudo-BS" from surreptitious diuretic intake (two patients) or vomiting (one patient) were also included. HCT test consisted of the administration of 50 mg of HCT orally (1 mg/kg in children-adolescents) and measurement of the maximal diuretic-induced increase over basal in the subsequent 3 h of chloride fractional clearance. All but three patients with GS but no patients with BS and pseudo-BS showed blunted (<2.3%) response to HCT; patients with BS and the two patients with pseudo-BS from diuretic intake had increased response to HCT. No overlap existed between patients with GS and both patients with BS and pseudo-BS. The response to HCT test is blunted in patients with GS but not in patients with BS or nongenetic hypokalemia. In patients with the highly selected phenotype of normotensive hypokalemic alkalosis, abnormal HCT test allows prediction with a very high sensitivity and specificity of the Gitelman genotype and may avoid genotyping.

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BACKGROUND: Patients with chemotherapy-related neutropenia and fever are usually hospitalized and treated on empirical intravenous broad-spectrum antibiotic regimens. Early diagnosis of sepsis in children with febrile neutropenia remains difficult due to non-specific clinical and laboratory signs of infection. We aimed to analyze whether IL-6 and IL-8 could define a group of patients at low risk of septicemia. METHODS: A prospective study was performed to assess the potential value of IL-6, IL-8 and C-reactive protein serum levels to predict severe bacterial infection or bacteremia in febrile neutropenic children with cancer during chemotherapy. Statistical test used: Friedman test, Wilcoxon-Test, Kruskal-Wallis H test, Mann-Whitney U-Test and Receiver Operating Characteristics. RESULTS: The analysis of cytokine levels measured at the onset of fever indicated that IL-6 and IL-8 are useful to define a possible group of patients with low risk of sepsis. In predicting bacteremia or severe bacterial infection, IL-6 was the best predictor with the optimum IL-6 cut-off level of 42 pg/ml showing a high sensitivity (90%) and specificity (85%). CONCLUSION: These findings may have clinical implications for risk-based antimicrobial treatment strategies.