Extracellular phospholipases are demonstrated virulence factors for a number of pathogenic microbes. The opportunistic pathogen Candida albicans is known to secrete phospholipases and these have been correlated with strain virulence. In an attempt to clone C. albicans genes encoding secreted phospholipases, Saccharomyces cerevisiae was transformed with a C. albicans genomic library and screened for lipolytic activity on egg-yolk agar plates, a traditional screen for phospholipase activity. Two identical clones were obtained which exhibited lipolytic activity. Nucleotide sequence analysis identified an ORF encoding a protein of 351 amino acid residues. Although no extensive homologies were identified, the sequence contained the Gly-X-Ser-X-Gly motif found in prokaryotic and eukaryotic lipases, suggesting a similar activity for the encoded protein. Indeed, culture supernatants from complemented yeast cells contained abundant hydrolytic activity against a triglyceride substrate and had no phospholipase activity. The data suggest that C. albicans, in addition to phospholipases, also has lipases. Southern blot analyses revealed that C. albicans may contain a lipase gene (LIP) family, and that a lipase gene(s) may be present in Candida parapsilosis, Candida tropicalis and Candida krusei, but not in Candida pseudotropicalis, Candida glabrata or S. cerevisiae. Northern blot analyses showed that expression of the LIP1 transcript, the cloned gene which encodes a lipase, was detected only when C. albicans was grown in media containing Tween 80, other Tweens or triglycerides as the sole carbon source, and not in Sabouraud Dextrose Broth or yeast/peptone/dextrose media. Additionally, carbohydrate supplementation inhibited LIP1 expression. Cloning this gene will allow the construction of LIP1-deficient null mutants which will be critical in determining the role of this gene in candidal virulence.
Although there are an increasing number of new antifungal agents available, the morbidity and mortality due to invasive mycoses remain high. The high rates of polyene toxicities and the development of azole resistance have raised the issue of using antifungal agents of these classes in combination, despite theoretical concerns regarding antagonism between such agents. This study was designed to evaluate the in vivo efficacy of combined therapy with amphotericin B and fluconazole against Candida albicans. Two distinct animal models were used in this study: a neutropenic-mouse model of hematogenously disseminated candidiasis and the infective-endocarditis rabbit model. Treatment efficacy was assessed by determining reductions in mortality as well as decreases in tissue fungal densities. In the neutropenic-mouse model, amphotericin B, as well as combination therapy, significantly prolonged survival compared to untreated controls (P < 10(-5) and P = 0.001, respectively). The fungal densities in the kidneys of neutropenic mice were significantly reduced with either amphotericin B monotherapy or amphotericin B-fluconazole combined therapy compared to those of controls (P < 10(-6)). Fluconazole monotherapy also reduced fungal densities in the kidneys; however, this decrease was not statistically significant (P = 0.17). In contrast, treatment with either fluconazole alone or combined with amphotericin B (but not amphotericin B monotherapy) significantly decreased fungal densities in the brain (P = 0.025). In the rabbit endocarditis model, amphotericin B monotherapy or combined therapy significantly decreased fungal densities in cardiac vegetations (P < 0.01 versus the controls). Although no significant antagonism was seen when fluconazole was given in combination with amphotericin B, combination therapy did not augment the antifungal activity of amphotericin B.
Long-term operation (390 days) of a continuous airlift reactor with aerobic granular biomass was successfully applied to treat a highly complex wastewater composed of: ammonium (1000 mg N L-1), o-cresol (100 mg L-1), phenol (100 mg L-1), quinoline (50 mg L-1) and salts (16 g salts L-1). High nitrogen loading rate (1.1 g N L-1 d-1) and organic loading rate of 0.7 (g COD L-1 d-1) were achieved for the simultaneous nitritation and complete biodegradation of the aromatic compounds. The successful operation of the granular airlift reactor can be related to (i) the growth of specialized microorganisms in the aerobic granules and (ii) the continuous feeding regime. Aerobic granules were maintained stable in spite of the high salinity conditions. Dissolved oxygen (DO) concentration and DO/ammonium concentrations ratio were the key parameters to select a suitable effluent for anammox or heterotrophic denitrification via nitrite. Besides, nitrous oxide emissions were related to the DO concentration in the reactor.
The effect of salinity over granular biomass treating a mixture of aromatic compounds (phenol, o-cresol and p-nitrophenol) was evaluated in a continuous airlift reactor. To mimic an industrial wastewater, increasing concentrations (from 2.0 to 29.0 g salts L(-1)) of a mixture of salts (MgSO4, NaCl, KCl, CaCl2 and NaHCO3) were introduced in the influent. The gradual salinity increase led to a good acclimation of the biomass obtaining complete biodegradation of the aromatic compounds and no accumulation of metabolic intermediates. However, a deterioration of the morphology of aerobic granules with a complete loss of granulation after 125 days was produced at 29.0 g salts L(-1). At that moment, anaerobic granules were added to promote granulation and after 50 days new aerobic granules were formed. These new aerobic granules remained stable for more than 100 days at the highest salinity condition with 100% removal of the mixture of aromatic compounds.
Patients were classified according morphologic, immunophenotypic, and cytogenetic findings. Treatment protocols were similar between centers. For patients up to 60 years of age, the treatment protocol was adapted according to performance status and the presence of comorbidities (in particular, cardiac disorders). Briefly, the conventional chemotherapy consisted of daunorubicin (45-90 mg/m 2 per day for 3 days) and cytarabine (100-200 mg/m 2 per day for 7 days) or thioguanine, cytosine arabinoside, and daunorubicin as induction, 1 followed by 3 or 4 cycles of consolidation therapy with high doses of cytarabine (.1 g/m 2 per day). For patients who did not achieve complete remission (CR) after 1 course of chemotherapy, a second course was administered between days 28 and 35 after the end of the first course. CR was assessed by bone marrow examination on day 28 after each course of chemotherapy. For those who needed it, a postremission therapy based on autologous or allogeneic transplantation was performed. Patients older than 60 years were treated with low-dose cytarabine; a combination of etoposide, thioguanine, and idarubicin; or best supportive care. The local research ethics board of each participating center approved the study. Research was conducted in accordance with the Declaration of Helsinki.The baseline characteristics are summarized in supplemental Table 1. One hundred thirty patients were enrolled in Recife (northeast Brazil, 54%), and 111 patients were enrolled in Campinas (southeast Brazil, 46%). Baseline features were similar between centers. The median age was 47 years (range, 18-97 years) with 114 males (47%). Sixty-two patients (26%) were older than 60 years. Pretreatment bone marrow samples were analyzed by G-banding cytogenetics, of which 187 (78%) were successful. According to Medical Research Council trials, 2 patients were stratified as follows: favorable (30/187, 16%), intermediate (119/187, 64%), and adverse (38/187, 20%). Overall, 101 patients (42%) were cytogenetically normal. To test whether the samples without cytogenetics results were missing at random, the overall survival (OS) was evaluated for patients with and without cytogenetics data. The 5-year OS rate did not differ between patients with (18%) and without (23%) available cytogenetics data (P 5 .372). Additionally, the entire cohort was fully characterized for NPM1 and FLT3-ITD mutations. Details can be found in the supplemental Data, available on the Blood Web site.Out of 241 enrolled patients, 39 patients (16%) who started the induction treatment were lost to follow-up without assessment for CR. Of 202 evaluable patients, 115 (57%) achieved complete hematologic remission. CR rates according to the cytogenetic risk stratification were 33%, 64%, and 77% for adverse, intermediate, and favorable groups, respectively (P 5 .001). The logistic regression analysis revealed that age (odds ratio [OR], 0.95; 95% confidence interval [CI], 0.93-0.98; P 5 .002) and cytogenetic risk stratification (OR, 0.41; 95% CI, 0.19-0.89; P 5 .024) wer...
In this cohort of XLRP families, as has happened in previous studies, RP3 also seems to be the most prevalent form of XLRP, and, based on the results, the authors propose a four-step protocol for molecular diagnosis of XLRP families.
The short-term effect of several aromatic compounds (o-cresol, p-nitrophenol, o-chlorophenol and quinoline) was evaluated over granular anammox sludge cultivated over 2 years in a Sequencing Batch Reactor (SBR). The anammox granular sludge had an average size of 1.0 ± 0.2 mm and was enriched in Brocadia sp. Specific Anammox Activity (SAA) batch tests with this granular biomass were carried out in the presence of o-cresol, p-nitrophenol, o-chlorophenol, quinoline and their mixtures. The anammox biomass was never exposed to the tested aromatic compounds, prior to the SAA tests. The concentration and the mixture of aromatic compounds had a strong effect over the loss of the anammox activity. The higher the concentrations of the aromatic compounds, the higher the reduction of the SAA. Quinoline and p-nitrophenol have a lower negative effect compared to o-cresol and ochlorophenol. The Luong inhibition model seems to adjust better the inhibition of anammox biomass by the tested aromatic compounds. Depending on the aromatic compound, toxic or inhibitory effect was measured. o-Cresol and o-chlorophenol caused a toxic effect whereas p-nitrophenol and quinoline produced an inhibitory effect. In general, synergistic effects were observed when mixtures of aromatic compounds were studied.
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