Identification of new omeprazole metabolites in wastewaters and surface waters

Omeprazole is one of the world-wide most consumed pharmaceuticals for treatment of gastric diseases. As opposed to other frequently used pharmaceuticals, omeprazole is scarcely detected in urban wastewaters and environmental waters. This was corroborated in a previous research, where parent omeprazole was not detected while four transformation products (TPs), mainly resulting from hydrolysis, were found in effluent wastewaters and surface waters. However, the low abundance of omeprazole TPs in the water samples together with the fact that omeprazole suffers an extensive metabolism, with a wide range of excretion rates (between 0.01 and 30%), suggests that human urinary metabolites should be investigated in the water environment. In this work, the results obtained in excretion tests after administration of a 40 mg omeprazole dose in three healthy volunteers are reported. Analysis by liquid chromatography coupled to hybrid quadrupole time-of-flight mass spectrometry (LC-QTOF MS) reported low concentrations of omeprazole in urine. Up to twenty-four omeprazole metabolites (OMs) were detected and tentatively elucidated. The most relevant OM was an omeprazole isomer, which obviously presented the same exact mass (m/z 346.1225), but also shared a major common fragment at m/z 198.0589. Subsequent analyses of surface water and effluent wastewater samples by both LC-QTOF MS and LC-MS/MS with triple quadrupole revealed that this metabolite (named as OM10) was the compound most frequently detected in water samples, followed by OM14a and OM14b. Up to our knowledge, OM10 had not been used before as urinary biomarker of omeprazole in waters. On the contrary, parent omeprazole was never detected in any of the water samples. After this research, it seems clear that monitoring the presence of omeprazole in the aquatic environment should be focused on the OMs suggested in this article instead of the parent compound.

Direct liquid chromatography-tandem mass spectrometry determination of underivatized glyphosate in rice, maize and soybean

The residue determination of the widely used herbicide glyphosate (GLY) is highly problematic due to its amphoteric character, low mass and lack of chemical groups that might facilitate its detection. Most methods developed up to now have employed pre-column or post-column derivatization to form fluorescent derivatives and/or to reduce the polar character of the analyte facilitating its chromatographic retention. The aim of this work is to evaluate the feasibility of performing the direct LC-MS/MS determination of GLY residues in vegetables. After testing several Hydrophilic Interaction Liquid Chromatography (HILIC) columns, Obelisc N was selected due to its better chromatographic retention. LC-MS/MS determination has been performed in negative ionization mode, monitoring up to four transitions to give high reliability to the identification/confirmation process. This approach has been evaluated for the determination of GLY residues in rice, maize and soybean samples, and the method validated at different concentrations in compliance with the maximum residue limits established in the current legislation. After sample extraction with water, a combination of extract dilution, partition with dichloromethane, and solid phase extraction (SPE) using Oasis HLB cartridges (depending on the sample matrix under analysis) was applied. Quantification was made by using isotope-labeled GLY as internal standard and calibration in solvent. The methodology developed allows the rapid determination of GLY residues avoiding the derivatization step typically applied for this herbicide. The most critical issue is the robustness of the Obelisc N column, which was found to suffer rapid degradation with time. Extreme care and continuous testing of retention times and peak shapes is required for a reliable determination.

Investigating the presence of omeprazole in waters by liquid chromatography coupled to low and high resolution mass spectrometry: degradation experiments

Omeprazole is one of the most consumed pharmaceuticals around the world. However, this compound is scarcely detected in urban wastewater and surface water. The absence of this pharmaceutical in the aquatic ecosystem might be due to its degradation in wastewater treatment plants, as well as in receiving water. In this work, different laboratory-controlled degradation experiments have been carried out on surface water in order to elucidate generated omeprazole transformation products (TPs). Surface water spiked with omeprazole was subjected to hydrolysis, photo-degradation under both sunlight and ultraviolet radiation and chlorination. Analyses by liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (LC-QTOF MS) permitted identification of up to 17 omeprazole TPs. In a subsequent step, the TPs identified were sought in surface water and urban wastewater by LC-QTOF MS and by LC coupled to tandem mass spectrometry with triple quadrupole. The parent omeprazole was not detected in any of the samples, but four TPs were found in several water samples. The most frequently detected compound was OTP 5 (omeprazole sulfide), which might be a reasonable candidate to be included in monitoring programs rather than the parent omeprazole.

Removal of emerging contaminants in sewage water subjected to advanced oxidation with ozone

Advanced oxidation processes (AOP) based on ozone treatments, assisted by ultrasounds, have been investigated at a pilot-plant scale in order to evaluate the removal of emerging contaminants in sewage water. Around 60 emerging contaminants, mainly pharmaceuticals from different therapeutically classes and drugs of abuse, have been determined in urban wastewater samples (treated and untreated) by LC-MS/MS. In a first step, the removal efficiency of these contaminants in conventional sewage water treatment plants was evaluated. Our results indicate that most of the compounds were totally or partially removed during the treatment process of influent wastewater. Up to 30 contaminants were quantified in the influent and effluent samples analysed, being antibiotics, anti-inflammatories, cholesterol lowering statin drugs and angiotensin II receptor antagonists the most frequently detected. Regarding drugs of abuse, cocaine and its metabolite benzoylecgonine were the most frequent. In a second step, the effectiveness of AOP in the removal of emerging contaminants remaining in the effluent was evaluated. Ozone treatments have been proven to be highly efficient in the removal, notably decreasing the concentrations for most of the emerging contaminants present in the water samples. The use of ultrasounds, alone or assisting ozone treatments, has been shown less effective, being practically unnecessary.

Improvements in the analytical methodology for the residue determination of the herbicide glyphosate in soils by liquid chromatography coupled to mass spectrometry

The determination of glyphosate (GLY) in soils is of great interest due to the widespread use of this herbicide and the need of assessing its impact on the soil/water environment. However, its residue determination is very problematic especially in soils with high organic matter content, where strong interferences are normally observed, and because of the particular physico-chemical characteristics of this polar/ionic herbicide. In the present work, we have improved previous LC-MS/MS analytical methodology reported for GLY and its main metabolite AMPA in order to be applied to "difficult" soils, like those commonly found in South-America, where this herbicide is extensively used in large areas devoted to soya or maize, among other crops. The method is based on derivatization with FMOC followed by LC-MS/MS analysis, using triple quadrupole. After extraction with potassium hydroxide, a combination of extract dilution, adjustment to appropriate pH, and solid phase extraction (SPE) clean-up was applied to minimize the strong interferences observed. Despite the clean-up performed, the use of isotope labelled glyphosate as internal standard (ILIS) was necessary for the correction of matrix effects and to compensate for any error occurring during sample processing. The analytical methodology was satisfactorily validated in four soils from Colombia and Argentina fortified at 0.5 and 5mg/kg. In contrast to most LC-MS/MS methods, where the acquisition of two transitions is recommended, monitoring all available transitions was required for confirmation of positive samples, as some of them were interfered by unknown soil components. This was observed not only for GLY and AMPA but also for the ILIS. Analysis by QTOF MS was useful to confirm the presence of interferent compounds that shared the same nominal mass of analytes as well as some of their main product ions. Therefore, the selection of specific transitions was crucial to avoid interferences. The methodology developed was applied to the analysis of 26 soils from different areas of Colombia and Argentina, and the method robustness was demonstrated by analysis of quality control samples along 4 months.

Use of time-of-flight mass spectrometry for large screening of organic pollutants in surface waters and soils from a rice production area in Colombia

The irrigate district of Usosaldaña, an important agricultural area in Colombia mainly devoted to rice crop production, is subjected to an intensive use of pesticides. Monitoring these compounds is necessary to know the impact of phytosanitary products in the different environmental compartments. In this work, surface water and soil samples from different sites of this area have been analyzed by applying an analytical methodology for large screening based on the use of time-of-flight mass spectrometry (TOF MS) hyphenated to liquid chromatography (LC) and gas chromatography (GC). Several pesticides were detected and unequivocally identified, such as the herbicides atrazine, diuron or clomazone. Some of their main metabolites and/or transformation products (TPs) like deethylatrazine (DEA), deisopropylatrazine (DIA) and 3,4-dichloroaniline were also identified in the samples. Among fungicides, carbendazim, azoxystrobin, propiconazole and epoxiconazole were the most frequently detected. Insecticides such as thiacloprid, or p,p'-DDT metabolites (p,p'-DDD and p,p'-DDE) were also found. Thanks to the accurate-mass full-spectrum acquisition in TOF MS it was feasible to widen the number of compounds to be investigated to other families of contaminants. This allowed the detection of emerging contaminants, such as the antioxidant 3,5-di-tertbutyl-4-hydroxy-toluene (BHT), its metabolite 3,5-di-tert-butyl-4-hydroxy-benzaldehyde (BHT-CHO), or the solar filter benzophenone, among others.

Importance of MS selectivity and chromatographic separation in LC-MS/MS-based methods when investigating pharmaceutical metabolites in water. Dipyrone as a case of study

Pharmaceuticals are emerging contaminants of increasing concern because of their presence in the aquatic environment and potential to reach drinking-water sources. After human and/or veterinary consumption, pharmaceuticals can be excreted in unchanged form, as the parent compound, and/or as free or conjugated metabolites. Determination of most pharmaceuticals and metabolites in the environment is commonly made by liquid chromatography (LC) coupled to mass spectrometry (MS). LC coupled to tandem MS is the technique of choice nowadays in this field. The acquisition of two selected reaction monitoring (SRM) transitions together with the retention time is the most widely accepted criterion for a safe quantification and confirmation assay. However, scarce attention is normally paid to the selectivity of the selected transitions as well as to the chromatographic separation. In this work, the importance of full spectrum acquisition high-resolution MS data using a hybrid quadrupole time-of-flight analyser and/or a suitable chromatographic separation (to reduce the possibility of co-eluting interferences) is highlighted when investigating pharmaceutical metabolites that share common fragment ions. For this purpose, the analytical challenge associated to the determination of metabolites of the widely used analgesic dipyrone (also known as metamizol) in urban wastewater is discussed. Examples are given on the possibilities of reporting false positives of dypirone metabolites by LC-MS/MS under SRM mode due to a wrong assignment of identity of the compounds detected.

Current use of high-resolution mass spectrometry in the environmental sciences

During the last two decades, mass spectrometry (MS) has been increasingly used in the environmental sciences with the objective of investigating the presence of organic pollutants. MS has been widely coupled with chromatographic techniques, both gas chromatography (GC) and liquid chromatography (LC), because of their complementary nature when facing a broad range of organic pollutants of different polarity and volatility. A clear trend has been observed, from the very popular GC-MS with a single quadrupole mass analyser, to tandem mass spectrometry (MS-MS) and, more recently, high-resolution mass spectrometry (HRMS). For years GC has been coupled to HR magnetic sector instruments, mostly for dioxin analysis, although in the last ten years there has been growing interest in HRMS with time-of-flight (TOF) and Orbitrap mass analyzers, especially in LC-MS analysis. The increasing interest in the use of HRMS in the environmental sciences is because of its suitability for both targeted and untargeted analysis, owing to its sensitivity in full-scan acquisition mode and high mass accuracy. With the same instrument one can perform a variety of tasks: pre- and post-target analysis, retrospective analysis, discovery of metabolite and transformation products, and non-target analysis. All these functions are relevant to the environmental sciences, in which the analyst encounters thousands of different organic contaminants. Thus, wide-scope screening of environmental samples is one of the main applications of HRMS. This paper is a critical review of current use of HRMS in the environmental sciences. Needless to say, it is not the intention of the authors to summarise all contributions of HRMS in this field, as in classic descriptive reviews, but to give an overview of the main characteristics of HRMS, its strong potential in environmental mass spectrometry and the trends observed over the last few years. Most of the literature has been acquired since 2005, coinciding with the growth and popularity of HRMS in this field, with a few exceptions that deserve to be mentioned because of their relevance.

Indolent evolution of an episode of acute gastroenteritis complicated with portal pneumatosis

The discovery of gas in the portal system related to indolent clinical settings has increased in recent years due to a growth in the performance of imaging tests. We report the first case of spontaneous resolution of portal pneumatosis due to acute gastroenteritis described in the literature.

Dissection of the ascending aorta in a patient with HLA-B27 associated ankylosing spondylitis

We describe a 38-year-old patient with ankylosing spondylitis complicated by a non-traumatic dissection of the ascending aorta without concomitant Marfan's syndrome.

Aggressive transformation of a quiescent primary bone lymphoma simulating Paget's disease

Primary multifocal osseous lymphoma is a rare and poorly recognized entity. Here, we present an instructive case of a young man who, six years after a local contusion of the left ankle, developed a painful polylobulated large soft tissue mass. This mass turned out to have arisen from the transformation of a centro follicular non-Hodgkin's lymphoma into a diffuse large B-cell lymphoma involving the calcaneus, talus, cuboid and navicular bones. The diagnostic difficulties as well as the implications of this aggressive transformation are highlighted here.

[Fuchs' heterochromic cyclitis without heterochromia: a diagnostic approach]

OBJECTIVE

To obtain diagnostic guidelines of Fuchs' heterochromic cyclitis (FHC) in the absence of heterochromia using Bayesian methods.

METHODS

The pre-test and post-test likelihood that a certain patient without heterochromia (but with other characteristic symptoms of the disease such as iris nodules, cataracts, glaucoma or vitritis) has FCH, was assessed by the Bayes' theorem for conditioned likelihood. The prevalence values of FCH and the presentation rate of symptoms in FCH and in other forms of anterior uveitis were obtained from published literature data.

RESULTS

In the absence of heterochromia, the combination of iris nodules together with cataracts, vitritis or glaucoma, and the association of the last three symptoms in the absence of nodules, resulted in an accumulated likelihood of more than 50% of subjects having the disease.

CONCLUSIONS

The coincidence in one patient of several indicative symptoms, even in the absence of heterochromia, may make FCH a likely diagnostic option.

[Measurement of lens density with a Scheimpflug camera in diabetic patients]

OBJECTIVE

To assess if diabetes, in patients without cataracts or diabetic retinopathy, alters the densitometric values of the lens and to what degree this occurs.

METHODS

A total of 93 patients, divided into two groups, were studied: the diabetic patients had a visual acuity equal to or greater than 0.8 and normal eye funduscopy, and the control group consisted of healthy patients of a similar age. Measurements in all patients were made with the Scheimpflug camera and the lens density of the anterior capsule, anterior cortex and nucleus was defined. The values obtained in the two groups were compared by analysis of variance (ANOVA).

RESULTS

All densitometric values were greater in the diabetic patients than in the normal controls. The greatest difference was seen in the values of the anterior capsule, followed by the nucleus and cortex. The differences approached statistical significance (P=0.07) only in the case of the anterior capsule.

CONCLUSIONS

Diabetes increases densitometric values of the anterior capsule and to a lesser degree of the anterior cortex. However, further studies are necessary to verify if this alteration is of significance.

Behavioral profile of SB 269970, a selective 5-HT(7) serotonin receptor antagonist, in social encounters between male mice

The 5-HT(7) receptor is targeted by several antipsychotics, such as pimozide or clozapine, which have demonstrated antiaggressive properties in laboratory animal models. Likewise, 'in situ' hybridization and autoradiography studies have revealed moderate to high densities of 5-HT(7) receptors in limbic areas and hypothalamus, which have long been involved in the control of aggression. However, to date there is no evidence concerning the role of this receptor in the regulation of aggression. This study was designed to examine the effects of SB 269970 (1, 2, 4, 8, 16 and 32 mg/kg, i.p.), a selective 5-HT(7) receptor antagonist, on agonistic behavior elicited by isolation in mice. Individually housed mice were exposed to anosmic standard opponents 15 min after drug administration and encounters were videotaped and evaluated using an ethopharmacologically-based analysis. The results indicated that SB 269970 did not produce any significant behavioral changes, suggesting that 5-HT(7) receptors might not be involved in the modulation of aggression. Further studies with other selective ligands for these receptors are needed to confirm these findings.

[Neurological follow-up of very low birth weight newborns at the age of two years (1998-1999)]

BACKGROUND

Because of improved obstetric and neonatal care, there is growing interest in the later outcome of very low birth weight newborns.

OBJECTIVES

The aim of this study was to evaluate the survival rate of very low birth weight newborns and to identify disabilities at the age of 2 years.

MATERIAL AND METHODS

An observational, follow-up study was performed of neonates with a birth weight of under 1,500 grams born between 1998 and 1999. The follow-up program included pediatric, maturative, neurological, psychological, ophthalmological, and audiological evaluation. Neurosensorial disabilities were classified as mild, moderate, or severe.

RESULTS

One hundred thirty-six very low birth weight newborns were admitted. The survival rate was 77.9 % and 83.9 % completed the follow-up to the age of 2 years. The neurosensorial disability rate was 20.2 %; disability was severe in 9 %, moderate in 1.1 %, and mild in 10.1 %. In patients lost to follow-up, birth weight was higher, gestational age was older, and sonographic findings were more frequently normal.

CONCLUSION

Survival in very low birth weight newborns has increased with improved neonatal care. The presence of sequelae was similar to that found in other follow-up studies. A substantial number of patients were lost to follow up, which influenced the disability rates.

Baker's asthma in a child

BACKGROUND

baker's asthma is a well-known occupational lung disease which usually develops in adults. We report the case of a two years old boy who suffered from asthma, urticaria and atopic dermatitis for twelve months, whose symptoms were associated to visits to his grandfather's bakery.

METHODS AND RESULTS

skin prick tests (SPT) were made to dust mites, moulds, flours, alfa-amylase and egg. It was also determined total IgE and specific IgE antibodies to alfa-amylase and flours. Subsequently, a challenge test was carried out with wheat flour. The SPTs were positive to flours, alfa-amylase and egg. The determination of specific IgE antibodies showed 2.64 kU/L to wheat, 0.79 kU/L to glyadin and 2.98 kU/L to alfa-amylase. The patient developed asthma and rhinitis after manipulating wheat flour for 10 min.

CONCLUSIONS

we demonstrated a type I hypersensitivity to wheat flour and alfa-amylase in a two years old child by SPT, specific IgE antibodies and challenge test. This case in the childhood equivalent of occupational baker's asthma.

[Self-care and education for the asthmatic patient]

Asthma constitutes one of the most frequent chronic illnesses during infant ages and although is represents a minor illness in the majority of cases, its chronic course, the limitation of activities that it implies and the possibility that serious exacerbations appear, make it a pathology that has great impact on a social-health level. Over the last few years it appears that there is an increase in both the occurrence as well as the morbidity and the mortality of asthma. On the other hand, it is know that the most serious consequences of asthma can, to a large extent, be prevent and we can compare prevention experiences that have been going on for a long time, that have demonstrated their efficiency in other countries. Numerous health control and promotion programmes for asthma have shown that the patients education and their inclusion in programmes on self care improves the therapeutic performance, allowing patients to have a better quality of live and they influence favourably on the course of the illness. The guides and the consensus on the treatment of asthma insist that the education of the patient should start at the moment the illness is diagnosed and that he should be integrated into a continual assistance programme that includes all the people related to the patients treatment, the specialist, the doctors and nurses. The clinic should instruct the patient on the nature of asthma, on the treatment options, and should indicate a treatment plan that is simple, but compatible, with optimum care and encourage an active participation. A personalised education can be carried out but additional education resources will also be involved, in groups, and supported by established programmes. In order to achieve this objetctives, the health programme should be adapted to the epidemiological and cultural characteristics of the population it is aimed at, choosing groups of patients that are as homogeneous as possible, taking into account the seriousness of the illness, the patients age and the demographic characteristics. It is necessary to use strict criteria when knowing which patients can obtain the greatest benefits from the self care programmes, aiming at making the resources as beneficial as possible.

[Presentation of Burkitt's lymphoma in nasal sinus]

Burkitt' lymphoma is a malignant, non-Hodgkin's lymphoma of high grade that present two clinical from the african or endemic form affects near the middle of children of central africa and the american or sporadic form, that was first described in North American and the clinical setting was similar to endemic form. In our geographic area is an unusual entity. We present a clinical case of marrocan child that the first symptom was nasosinusal.