Relevance of the diagnosis of hypersensitivity reactions to antineoplastic and biological agents: experience with drug provocation test.

Summary: Background. Evidence regarding drug provocation test (DPT) with chemotherapeutic agents is scarce. The aim of our study is to describe the experience of DPT in patients with a history of hypersensitivity reactions (HSRs) to antineoplastic and biological agents. Methods. This was an eight-year retrospective, observational, descriptive study of patients with a history of HSRs to chemotherapy who were submitted to DPT. Anamnesis, skin tests (ST) and DPT were analyzed. Patients with a negative DPT were submitted to at least one regular supervised administration (RSA). Patients with positive DPT or HSR during RSA were offered rapid drug desensitization (RDD). Results. A total of 54 patients were submitted to DPT. The most common suspected drugs were platins (n = 36), followed by taxanes (n = 11). Most initial reactions were classified as grade II (n = 39) according to Brown's grading system. ST with platinum (n = 35), taxanes (n = 10) and biological agents (n = 4) were negative, except for one intradermal test with paclitaxel, which was positive. A total of 64 DPTs were performed. Eleven percent of all DPTs were positive (platins (n = 6), doxorubicin (n = 1)). Of the 57 RSA with the culprit drugs, 2 were positive (platins). The diagnosis of hypersensitivity was confirmed by DPT/RSA in 9 patients. All patients with positive DPT/RSA presented HSRs of equal or less severity than the initial one. Conclusions. DPT followed by RSA allowed to exclude HSRs in 45 patients (55 culprit drugs). DPT before desensitization prevents non-hypersensitivity patients from undergoing RDD. In our study DPT was safe, all reactions were managed by an allergist.

Dose to the interventional radiologist in CTF-guided procedures.

The aim of this work was to assess the occupational dose received by an interventional radiologist (IR) during computed tomography fluoroscopy (CTF)-guided procedures; to identify the most exposed areas of the body including the hands and fingers; to suggest recommendations for individual monitoring; and to improve radiation safety of the practice. A total of 53 CTF-guided procedures were studied. Twelve whole-body dosimeters were worn by the IR in each procedure for the assessment of the personal dose equivalent, Hp(10), on the chest, waist, and back, both over and under the lead apron, as well as the personal dose equivalent, Hp(0.07), on both arms, knees, and feet. Special gloves with casings to fit extremity dosimeters were prepared to assess Hp(0.07) to the fingers. The measured chest dose values were higher than those on the waist and back; the dominant hand or the left side was the most exposed. In general, the ring, middle, and index fingers of the dominant hand were the most exposed (maximum in the 36-39 mSv range), while wrist dose was negligible compared to finger doses. Based on the results obtained the following recommendations are suggested: protective devices (lead aprons, thyroid shield, and goggles) should be worn; Hp(10) should be assessed at the chest level both above and below the lead apron; finger doses can be measured on the basis of each middle finger; the arm closer to the beam should be monitored; and finally, a wrist dosimeter will not provide useful information.

Hypersensitivity to antiretroviral drugs.

Summary: Background. Antiretroviral therapy (ART) may be responsible for hypersensitivity reactions varying in severity, clinical manifestations and frequency. Case report. We report the case of a 47-year-old woman with HIV infection who developed a delayed mucocutaneous reaction after treatment with ART. Hypersensitivty reaction (HR) to emtricitabine and tenofovir was considered probable based on positive patch tests (PT) and hypersensitivity reaction to nevirapine was confirmed by drug provocation test. Discussion. The diagnosis of HR to ART remains a diagnostic challenge, partly due to unknown mechanism and the absence of validated diagnostic tools. Patch testing may represent a useful method for confirming hypersensitivity. Further investigation in this area is required, so that successful management strategies can be offered, preventing loss of potent and viable antiretroviral agents.

Bodybuilding protein supplements and cow's milk allergy in adult.

Summary: We report a case of a previously healthy 24-year-old man with a 3-month history of gastrointestinal symptoms during exercise and also few minutes after the ingestion of cow's milk (CM) without exercise. He reported the ingestion of a blend of hydrolyzed whey and casein proteins for bodybuilding for the last 2 years. The in vivo tests showed positivity to CM, α-lactalbumin, ß-lactoglobulin and casein extracts, and also to the protein supplement. The serum specific IgE was positive for CM, ß-lactoglobulin and α-lactalbumin. The in vivo and in vitro tests results suggested an IgE-mediated CMA. Adult-onset CMA has been rarely reported, and to our knowledge this is the first case possibly related to bodybuilding supplements. The authors theorize that the presentation of large amounts of proteins in the gastrointestinal tract may favor sensitization.

Forensic miRNA: potential biomarker for body fluids?

In forensic investigation, body fluids represent an important support to professionals when detected, collected and correctly identified. Through many years, various approaches were used, namely serology-based methodologies however, their lack of sensitivity and specificity became difficult to set aside. In order to sidetrack the problem, miRNA profiling surged with a real potential to be used to identify evidences like urine, blood, menstrual blood, saliva, semen and vaginal secretions. MiRNAs are small RNA structures with 20-25 nt whose proprieties makes them less prone to degradation processes when compared to mRNA which is extremely important once, in a crime scene, biological evidences might be exposed to several unfavorable environmental factors. Recently, published studies were able to identify some specific miRNAs, however their results were not always reproducible by others which can possibly be the reflection of different workflow strategies for their profiling studies. Given the current blast of interest in miRNAs, it is important to acknowledge potential limitations of miRNA profiling, yet, the lack of such studies are evident. This review pretends to gather all the information to date and assessed a multitude of factors that have a potential aptitude to discrediting miRNA profiling, such as: methodological approaches, environmental factors, physiological conditions, gender, pathologies and samples storage. It can be asserted that much has yet to be made, but we pretend to highlight a potential answer for the ultimate question: Can miRNA profiling be used as the forensic biomarker for body fluids identification?

IgE-mediated metamizol allergy and the usefulness of the cellular allergen stimulation test.

Metamizol is a pyrazolone-derivative nonsteroidal anti-inflammatory drug that is commonly associated with hypersensitivity reactions. Some of these reactions are IgE-mediated and potentially severe, which limits the diagnosis based on oral drug challenge. We describe 6 selective metamizol hypersensitivity cases, regarding clinical evaluation and diagnosis management, with focus on the usefulness of skin tests and the cellular allergen stimulation test (CAST). All patients were female, aged 27 to 50 years old. All had immediate reactions after metamizol administration: 3 had anaphylaxis and 3 had urticaria and angioedema. Skin prick tests with metamizol were positive in 2 patients. Intradermal tests were positive in the remaining, all with 1/100 dilution, and elicited systemic reactions in 2 of them. CAST to metamizol was negative in all cases. The patients tolerated other nonsteroidal anti-inflammatory drugs. Skin tests proved to be a good diagnostic method to identify IgE-mediated metamizol allergy, although skin tests elicited systemic symptoms in some cases. Despite this being a small sample, our results showed a very low sensitivity for CAST which differs from data previously reported in the literature.

Preliminary assessment of the dose to the interventional radiologist in fluoro-CT-guided procedures.

A preliminary assessment of the occupational dose to the intervention radiologist received in fluoroscopy computerised tomography (CT) used to guide the collection of lung and bone biopsies is presented. The main aim of this work was to evaluate the capability of the reading system as well as of the available whole-body (WB) and extremity dosemeters used in routine monthly monitoring periods to measure per procedure dose values. The intervention radiologist was allocated 10 WB detectors (LiF: Mg, Ti, TLD-100) placed at chest and abdomen levels above and below the lead apron, and at both right and left arms, knees and feet. A special glove was developed with casings for the insertion of 11 extremity detectors (LiF:Mg, Cu, P, TLD-100H) for the identification of the most highly exposed fingers. The H(p)(10) dose values received above the lead apron (ranged 0.20-0.02 mSv) depend mainly on the duration of the examination and on the placement of physician relative to the beam, while values below the apron are relatively low. The left arm seems to receive a higher dose value. H(p)(0.07) values to the hand (ranged 36.30-0.06 mSv) show that the index, middle and ring fingers are the most highly exposed. In this study, the wrist dose was negligible compared with the finger dose. These results are preliminary and further studies are needed to better characterise the dose assessment in CT fluoroscopy.

Small heat-shock protein Hsp12 contributes to yeast tolerance to freezing stress.

The HSP12 gene encodes one of the two major small heat-shock proteins of Saccharomyces cerevisiae and is induced under different conditions, such as low and high temperatures, osmotic or oxidative stress and high sugar or ethanol concentrations. However, few studies could demonstrate any correlation between HSP12 deletion or overexpression and a phenotype of sensitivity/resistance, making it difficult to attribute a role for Hsp12p under several of these stress conditions. We investigated the possible role of Hsp12p in yeast freezing tolerance. Contrary to what would be expected, the hsp12 null mutant when subjected to prolonged storage at -20 degrees C showed an increased resistance to freezing when compared with the isogenic wild-type strain. Because the mutant strain displayed a higher intracellular trehalose concentration than the wild-type, which could mask the effect of manipulating HSP12, we overexpressed the HSP12 gene in a trehalose-6-phosphate synthase (TPS1) null mutant. The tps1Delta strain overexpressing HSP12 showed an increase in resistance to freezing storage, indicating that Hsp12p plays a role in freezing tolerance in a way that seems to be interchangeable with trehalose. In addition, we show that overexpression of HSP12 in this tps1Delta strain also increased resistance to heat shock and that absence of HSP12 compromises the ability of yeast cells to accumulate high levels of trehalose in response to a mild heat stress.

Mitochondria-dependent apoptosis in yeast.

Mitochondrial involvement in yeast apoptosis is probably the most unifying feature in the field. Reports proposing a role for mitochondria in yeast apoptosis present evidence ranging from the simple observation of ROS accumulation in the cell to the identification of mitochondrial proteins mediating cell death. Although yeast is unarguably a simple model it reveals an elaborate regulation of the death process involving distinct proteins and most likely different pathways, depending on the insult, growth conditions and cell metabolism. This complexity may be due to the interplay between the death pathways and the major signalling routes in the cell, contributing to a whole integrated response. The elucidation of these pathways in yeast has been a valuable help in understanding the intricate mechanisms of cell death in higher eukaryotes, and of severe human diseases associated with mitochondria-dependent apoptosis. In addition, the absence of obvious orthologues of mammalian apoptotic regulators, namely of the Bcl-2 family, favours the use of yeast to assess the function of such proteins. In conclusion, yeast with its distinctive ability to survive without respiration-competent mitochondria is a powerful model to study the involvement of mitochondria and mitochondria interacting proteins in cell death.

Sugar utilization patterns and respiro-fermentative metabolism in the baker's yeast Torulaspora delbrueckii.

The highly osmo- and cryotolerant yeast species Torulaspora delbrueckii is an important case study among the non-Saccharomyces yeast species. The strain T. delbrueckii PYCC 5321, isolated from traditional corn and rye bread dough in northern Portugal, is considered particularly interesting for the baking industry. This paper reports the sugar utilization patterns of this strain, using media with glucose, maltose and sucrose, alone or in mixtures. Kinetics of growth, biomass and ethanol yields, fermentation and respiration rates, hydrolase activities and sugar uptake rates were used to infer the potential applied relevance of this yeast in comparison to a conventional baker's strain of Saccharomyces cerevisiae. The results showed that both maltase and maltose transport in T. delbrueckii were subject to glucose repression and maltose induction, whereas invertase was subject to glucose control but not dependent on sucrose induction. A comparative analysis of specific sugar consumption rates and transport capacities suggests that the transport step limits both glucose and maltose metabolism. Specific rates of CO(2) production and O(2) consumption showed a significantly higher contribution of respiration to the overall metabolism in T. delbrueckii than in S. cerevisiae. This was reflected in the biomass yields from batch cultures and could represent an asset for the large-scale production of the former species. This work contributes to a better understanding of the physiology of a non-conventional yeast species, with a view to the full exploitation of T. delbrueckii by the baking industry.

A new acceleration technique for the design of fibre gratings.

In this paper we propose a novel acceleration technique for the design of fibre gratings based on Genetic Algorithm (GA). It is shown that with an appropriate reformulation of the wavelength sampling scheme it is possible to design high quality optical filters with low computational effort. Our results will show that the proposed technique can reduce significantly the GA's processing time.

Activity of essential oils from Mediterranean Lamiaceae species against food spoilage yeasts.

The essential oils from aerial parts of Melissa officinalis, Lavandula angustifolia, Salvia officinalis, and Mentha piperita were analyzed by gas chromatography and gas chromatography-mass spectrometry. Their antimicrobial activities were evaluated against five food spoilage yeasts, Torulaspora delbrueckii, Zygosaccharomyces bailii, Pichia membranifaciens, Dekkera anomala, and Yarrowia lipolytica. Saccharomyces cerevisiae was also used as a reference. The oils were preliminarily screened by a disc diffusion technique, with the most active being the oil from M. officinalis. MICs were determined by the broth dilution method, and the main components of the oils were also tested by this method. The essential oil of M. officinalis at 500 microg/ml completely inhibited the growth of all yeast species. The main component of the oil of M. officinalis is citral (neral plus geranial) (58.3%), which showed a marked fungitoxic effect, contributing to its high activity.

Mycobacterial infection in farmed turbot Scophthalmus maximus.

Mycobacteriosis (piscine tuberculosis) has been reported to affect a wide range of freshwater and marine fish species; however, this is the first report describing mycobacterial infections in turbot Scophthalmus maximus. High numbers of granulomas were initially observed in the organs of moribund farmed turbot. Bacteriological analysis of organs with granulomas led to the isolation of Mycobacterium marinum. Further analysis, to determine the prevalence of the infection in the farm and to identify its source, showed the occurrence of a dual infection by M. marinum and M. chelonae. The presence of Nocardia sp. in some of the fish infected with mycobacteria was also detected. The presence of granulomas in internal organs of apparently healthy fish indicated a high prevalence of the disease, a conclusion that was supported by isolating mycobacteria from all fish with or without granulomas. The infection was probably responsible for the mortality observed (approximately 2% mo(-1)), as most of the recently dead fish presented high numbers of granulomas and isolation of mycobacteria was possible from all of the fish. The isolation of M. marinum from the inlet water suggested this as the most plausible source for the infection occurring in the farm.

Cell cycle analysis of yeasts.

Staining protocols generally designed for the flow cytometric analysis of the cell cycle in mammalian cells are frequently not satisfactory for quantification of the various cell-cycle phases in yeasts. High CVs limit the accuracy of DNA content measurement and estimates of populations in cell-cycle compartments. This unit describes a staining procedure for yeasts using the sensitive nucleic acid stain SYBR Green I, which binds to double-stranded DNA with high selectivity and which has a much higher fluorescence quantum yield upon binding than most other commonly used fluorophores. The properties of this dye combined with optimized sample processing provide high-resolution DNA analysis, with half-peak CVs around 3 to 4% and clear-cut identification of the S phase.

Construction of a genomic library of the food spoilage yeast Zygosaccharomyces bailii and isolation of the beta-isopropylmalate dehydrogenase gene (ZbLEU2).

A genomic library of the yeast Zygosaccharomyces bailii ISA 1307 was constructed in pRS316, a shuttle vector for Saccharomyces cerevisiae and Escherichia coli. The library has an average insert size of 6 kb and covers the genome more than 20 times assuming a genome size similar to that of S. cerevisiae. This new tool has been successfully used, by us and others, to isolate Z. bailii genes. One example is the beta-isopropylmalate dehydrogenase gene (ZbLEU2) of Z. bailii, which was cloned by complementation of a leu2 mutation in S. cerevisiae. An open reading frame encoding a protein with a molecular mass of 38.7 kDa was found. The nucleotide sequence of ZbLEU2 and the deduced amino acid sequence showed a significant degree of identity to those of beta-isopropylmalate dehydrogenases from several other yeast species. The sequence of ZbLEU2 has been deposited in the EMBL data library under accession number AJ292544.

Yeasts as a model for assessing the toxicity of the fungicides Penconazol, Cymoxanil and Dichlofluanid.

In the present work the sensitivity of yeast strains of Kluyveromyces marxianus, Pichia anomala, Candida utilis, Schizosaccharomyces pombe and Saccharomyces cerevisiae, to the fungicides cymoxanil, penconazol, and dichlofluanid, was evaluated. Dichlofluanid induced the most negative effects, whereas penconazol in general was not very toxic. Overall, our results show that the parameters IC50 for specific respiration rates of C. utilis and S. cerevisiae and C(D) for cell viability of S. cerevisiae can be applied to quantify the toxicity level of the above compounds in yeast. Hence, could be explored as an alternative or at least as a complementary test in toxicity studies and, therefore, its potential for inclusion in a tier testing toxicity test battery merits further research.