Susceptibility of Candida spp. isolated from blood cultures as evaluated using the M27-A3 and new M27-S4 approved breakpoints

The high mortality rates associated with candidemia episodes and the emergence of resistance to antifungal agents necessitate the monitoring of the susceptibility of fungal isolates to antifungal treatments. The new, recently approved, species-specific clinical breakpoints (SS-CBPs)(M27-S4) for evaluating susceptibility require careful interpretation and comparison with the former proposals made using the M27-A3 breakpoints, both from CLSI. This study evaluated the susceptibility of the different species of Candida that were isolated from candidemias based on these two clinical breakpoints. Four hundred and twenty-two isolates were identified and, among them, C. parapsilosis comprised 46.68%, followed by C. albicans (35.78%), C. tropicalis (9.71%), C. glabrata (3.55%), C. lusitaniae (1.65%), C. guilliermondii (1.65%) and C. krusei (0.94%). In accordance with the M27-A3 criteria, 33 (7.81%) non-susceptible isolates were identified, of which 16 (3.79%) were resistant to antifungal agents. According to SS-CBPs, 80 (18.95%) isolates were non-susceptible, and 10 (2.36%) of these were drug resistant. When the total number of non-susceptible isolates was considered, the new SS-CBPs detected 2.4 times the number of isolates that were detected using the M27-A3 interpretative criteria. In conclusion, the detection of an elevated number of non-susceptible species has highlighted the relevance of evaluating susceptibility tests using new, species-specific clinical breakpoints (SS-CBPs), which could impact the profile of non-susceptible Candida spp. to antifungal agents that require continuous susceptibility monitoring.

Chemical ecology of canarian laurel forest: Toxic diterpenes fromPersea indica (Lauraceae)

The tree speciesP. indica (Lauraceae) is an important endemism in the Canary Islands laurel forest and can readily be distinguished by its defoliated appearance due to the seasonal action of wild rats (Rattus rattus), which eat the plant and become intoxicated. These observations and the phytochemical interest of this plant species led us to study the potentially toxic chemicals responsible for such action. We found that an ethanolic extract ofP. indica and its water fraction were toxic when injected into laboratory mice. The mice also died after ingestion of the stems and showed a significant preference for those extracted and rehydrated with an 8% aqueous extract solution when compared with the water control. Two compounds that have been isolated from the toxic fraction and identified by spectroscopic methods are the polyhydroxy pentacyclic diterpenes ryanodol and cinnceylanol. Possible ecological implications are discussed.

Porosity estimation of concrete by ultrasonic NDE

The increasing number of concrete structures with symptoms of premature deterioration due to environmental action demands procedures to estimate the durability of this type of component. Concrete durability is related to porosity, which determines the intensity of interactions of the material with aggressive agents. The pores and capillaries inside the structure facilitate the destructive processes that generally begin in the surface. In this work, an ultrasonic NDE technique to estimate the porosity of concrete is developed. The method is based on the analysis of the mechanical behaviour of mortar probes built with calibrated sand, in which the concentration of water-cement mixture has been varied. In this sense, data of sound velocity are correlated with data of porosity, which have been previously measured by destructive measurements.

Signal-to-noise ratio enhancement based on the whitening transformation of colored structural noise

In the ultrasonic testing and evaluation of highly scattering materials (i.e. non-homogeneous media such as composites, layered and clad materials) structural noise is an important limitation to the visibility of flaw echoes. This noise cannot be reduced by conventional linear filtering or by time-averaging techniques. In order to enhance the defect-to-background noise ratio (SNR), many different algorithms have been developed over the years. This work analyzes three new strategies for SNR enhancement based on the whitening transformation of the colored structural noise. By using this transformation, the small spectral differences between noise and flaw echoes are exploited, thereby allowing an improvement in the visibility of the flaw.

Paramyosin is a major target of the human IgA response against Schistosoma japonicum

Human resistance and susceptibility to schistosomiasis is associated with age and specific antibody isotype responses against worm (SWAP) and egg (SEA) antigens. In a cross-sectional study of 176 individuals infected with Schistosoma japonicum in the Philippines, strikingly similar isotype response patterns against SWAP and SEA was observed when compared to other endemic areas. Interestingly, IgA titres to SWAP correlated with older age among S. japonicum-infected individuals (n = 176, P < 0.01), suggesting a role for this isotype in protective immunity. To identify the molecular targets of human IgA, 17 high-IgA/SWAP responders were identified from the said population. IgA antibodies from the majority (14/17) of these individuals recognized a band of 97 kDa (Sj97), comigrating in immunoblots with the myofibrillar protein paramyosin. The antigen was confirmed as paramyosin by expressed sequence tag (EST)-analysis of four clones obtained by screening an adult S. japonicum cDNA library with pooled IgA antisera and mouse antiparamyosin polyclonal antibodies. The identification of paramyosin as a major target of human IgA raises its potential as a vaccine candidate that targets mucosal immune responses. Since this antigen is exposed on the parasite surface only during the lung stages, we propose that human IgA contributes to parasite attrition during schistosome migration in the lungs.

Diagnostic criteria and prognosis of perioperative myocardial infarction following coronary bypass

To evaluate the incidence of perioperative myocardial infarction (PMI), serial determinations of serum creatine kinase isoenzymes (CK-MB), electrocardiograms (ECGs), and pyrophosphate myocardial scans were performed in 112 patients undergoing isolated coronary bypass grafting. An abnormal increase in total CK-MB liberation (Q greater than 9.8 IU ml-1 kg) occurred in 25 patients (22.3%), new Q waves were present at ECG in 10 patients (8.9%), and the pyrophosphate myocardial scan was abnormal in 13 patients (11.6%). All tests were negative in 81 patients (72.3%). A diagnosis of PMI was established if confirmed by at least two of the techniques; this diagnosis was made in 15 patients (13.4%). The pattern of CK-MB liberation in patients with a PMI, characterized by a high peak and a prolonged release, was significantly different from that of patients without a PMI. The most important predictive factor for PMI was the duration of myocardial ischemia during the operation. Patients who had a PMI had more frequent early complications, and their prognosis at 2 years showed a 51% probability of remaining free of new cardiac events as compared to 96% for the group of patients without a PMI (p less than 0.001). PMI is not a benign complication of coronary bypass, and its detection appears improved by a combination of diagnostic tests.