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During nutrient scarcity, plants can adapt their developmental strategy to maximize their chance of survival. Such plasticity in development is underpinned by hormonal regulation, which mediates the relationship between environmental cues and developmental outputs. In legumes, endosymbiosis with nitrogen fixing bacteria (rhizobia) is a key adaptation for supplying the plant with nitrogen in the form of ammonium. Rhizobia are housed in lateral root-derived organs termed nodules that maintain an environment conducive to Nitrogenase in these bacteria. Several phytohormones are important for regulating the formation of nodules, with both positive and negative roles proposed for gibberellin (GA). In this study, we determine the cellular location and function of bioactive GA during nodule organogenesis using a genetically-encoded second generation GA biosensor, GIBBERELLIN PERCEPTION SENSOR 2 in Medicago truncatula. We find endogenous bioactive GA accumulates locally at the site of nodule primordia, increasing dramatically in the cortical cell layers, persisting through cell divisions and maintaining accumulation in the mature nodule meristem. We show, through mis-expression of GA catabolic enzymes that suppress GA accumulation, that GA acts as a positive regulator of nodule growth and development. Furthermore, increasing or decreasing GA through perturbation of biosynthesis gene expression can increase or decrease the size of nodules, respectively. This is unique from lateral root formation, a developmental program that shares common organogenesis regulators. We link GA to a wider gene regulatory program by showing that nodule-identity genes induce and sustain GA accumulation necessary for proper nodule formation.

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Omarigliptin (OMG) is an antidiabetic drug indicated for the treatment of type 2 diabetes mellitus. Forced degradation studies are practical experiments to evaluate the stability of drugs and to establish degradation profiles. Herein, we present the investigation of the degradation products (DPs) of OMG formed under various stress conditions. OMG was subjected to hydrolytic (alkaline and acidic), oxidative, thermal, and photolytic forced degradation. A stability-indicating ultra-fast liquid chromatography method was applied to separate and quantify OMG and its DPs. Five DPs were adequately separated and detected in less than 6 min, while other published methods detected four DPs. MS was applied to identify and obtain information on the structural elucidation of the DPs. Three m/z DPs confirmed previously published research, and two novel DPs were described in this paper. The toxicity of OMG and its DPs were investigated for the first time using in vitro cytotoxicity assays, and the sample under oxidative conditions presented significant cytotoxicity. Based on the results from forced degradation studies, OMG was found to be labile to hydrolysis, oxidation, photolytic, and thermal stress conditions. The results of this study contribute to the quality control and stability profile of OMG.

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Pterostilbene (PTS) is a drug candidate with low water solubility and poor bioavailability. On the other hand, drug:cyclodextrins complexes frequently provide bulk powders with low drug concentrations, which is crucial for obtention solid or semi-solid pharmaceutical dosage forms. In order to determine the optimal conditions for enhancing the solubility of PTS:BCD (ß-cyclodextrin) complex, a Box-Behnken design was performed. Although the optimal conditions have been applied, low complexation efficiency (0.127) and the bulk powder remained. A PTS:BCD:HPMC (HPMC, hydroxypropyl methylcellulose) ternary system was developed to overcome this limitation, comparing two media, water and a mixture of ethanol-water. When ethanol was used as a co-solvent, the PTS:BCD:HPMC ternary system (freeze-dried) contained 116.65 ± 1.40 mg/g of PTS. This value was 3.4-fold higher than the PTS content observed when the same ternary system was obtained in aqueous media (34.8 mg/g) and 2.8-fold higher than the PTS content observed for PTS:BCD complex (freeze-dried) obtained using ethanol as a co-solvent. Dissolution tests revealed that after 120 min, in a buffer with a pH value of 1.2, only 43% of PTS dissolved. In contrast, 80% and 90% of PTS were dissolved from the PTS:BCD complex and PTS:BCD:HPMC ternary system, respectively. Moreover, the dissolution was fast in a buffer with a pH value of 6.8. PTS:BCD complex reached the maximum PTS dissolution at 75 min and PTS:BCD:HPMC at 45 min. In summary, the results of this study demonstrated, for the first time, that low-bulk powders with a high content of PTS can be obtained from PTS:BCD:HPMC ternary systems using ethanol as a co-solvent. This new finding offers a valuable alternative for producing solid or semi-solid formulations containing highly soluble PTS.

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Vancomycin is used as an antimicrobial agent for the treatment of severe gram-positive infections. The importance of therapeutic monitoring of antimicrobials has led to the development of more specific sample preparation techniques capable of identifying with accuracy the concentration of this substance in the organism. An aliquot of 10 µl of plasma was transferred to Whatman 903 paper and dried at room temperature. The extraction method was performed by cutting and transferring the paper to a microtube and adding sodium phosphate buffer and internal standard. The mixture was shaken and centrifuged, and a 5-µl aliquot was injected into the analytical system. The optimization of the main parameters that can influence the extraction efficiency was performed using multivariate approaches to obtain the best conditions. The method developed was validated, providing coefficients of determination higher than 0.994 and a lower limit of quantification of 1 mg/L. Within- and between-run precision ranged from 11.4 to 17.30% and from 6.65 to 13.51%, respectively. This method was successfully applied to 75 samples of patients undergoing vancomycin therapy. The method was rapid, simple, and environmentally friendly with satisfactory analytical performance and was advantageous over the laborious and time-consuming methodologies used in therapeutic drug monitoring routine analyses.

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Electroosmotic flow (EOF) was determined in tridimensional (3D)-printed microchannels with dimensions smaller than 100 µm. Fused deposition modeling 3D printing using thermoplastic filaments of PETG (polyethylene terephthalate glycol), PLA (polylactic acid), and ABS (acrylonitrile butadiene styrene) were used to fabricate the microchannels. The current monitoring method and sodium phosphate solutions at different pH values (3-10) were used for the EOF mobility (µEOF ) measurements, which ranged from 2.00 × 10-4 to 12.52 × 10-4  cm2  V-1  s-1 . The highest and the smallest µEOF were obtained for the PLA and PETG microchannels, respectively. Adding the cationic surfactant cetyltrimethylammonium bromide to the sodium phosphate solution caused EOF direction reversion in all the studied microchannels. The obtained results can be interesting for developing 3D-printed microfluidic devices, in which EOF is relevant.

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Autoimmune encephalitis (AIE) is an inflammatory brain condition with multiple aetiologies but is mainly associated with paraneoplastic syndromes. Several antibodies described in AIE are being investigated in relation to different cancers, including antibodies against Contactin-associated protein-like 2 (Caspr2), which have been associated with thymoma but very rarely with lung cancer. The authors present the case of a 72-year-old man with cardiovascular risk factors, who presented with a 3-week history of left hemichorea following a first unprovoked seizure the week before, with no other signs or symptoms. The patient was submitted to extensive aetiological investigation, testing positive for anti-Caspr2 antibodies in the cerebrospinal fluid. AIE was diagnosed after other possible causes had been excluded. A PET scan showed signs of abnormal metabolism, with a lung biopsy confirming lung adenocarcinoma. This case highlights a very rare association and the importance of a thorough aetiological investigation for neurological complaints. LEARNING POINTS: Neurological complaints require a thorough aetiological investigation, and positive findings on imaging studies must be carefully examined.Anti-Caspr2 antibodies are classically associated with Morvan syndrome, but other neurological presentations must also be considered.Anti-Caspr2 autoimmune encephalitis may be the primary presentation of lung adenocarcinoma.

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A liver abscess (LA) is the most common type of visceral abscess. While biliary tract disorders are its most common etiology, clinicians should also consider less frequent causes such as iatrogenic complications due to certain interventions. One of these unusual causes is related to endoscopic retrograde cholangiopancreatography (ERCP) with endoscopic sphincterotomy (ES), a usually safe procedure that carries some risk of complications. We present the case of a 71-year-old female with a history of choledocholithiasis who underwent ERCP with ES without any immediate complications; she was discharged after 24 hours and readmitted three days later to the emergency room with fever and abdominal pain. An abdominal CT showed a liver abscess. Blood cultures were positive for Escherichia coli, Streptococcus anginosus, and Enterococcus faecalis, and the patient was started on directed antibiotic therapy with ampicillin, benzylpenicillin, and metronidazole. On day 17, due to hematochezia with hemodynamic instability, an urgent upper gastrointestinal endoscopy was performed, which revealed late post-ES bleeding, refractory to conventional endoscopic therapy. An ERCP was performed to control the bleeding by using a biliary fully covered self-expandable metal stent (FCSEMS), which was removed four weeks later. The follow-up CT showed a significant reduction of LA and the patient was discharged. This case highlights the association of two uncommon complications of ERCP: a LA and a major late post-ES bleeding. Clinicians should maintain a high index of suspicion for these complications in daily practice.

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Drug-induced pancreatitis is a rare though important condition that remains a diagnostic challenge. Most of the evidence relies on case reports, and clinicians should consider a high suspicion of the diagnosis after ruling out other causes. In particular, steroids are frequently used drugs that have recently been associated with acute pancreatitis. The authors present the case of a 60-year-old female admitted to the emergency room with a fever and shortness of breath. The SARS-CoV-2 test was positive, and the chest radiography was suggestive of COVID-19 pneumonia. The patient started dexamethasone because of respiratory failure. On Day 7, she developed epigastric pain radiating to the back and the amylase level was greater than 10 times the upper reference limit (1354 U/L). A detailed evaluation of the medical history, along with the exclusion of other possible etiologies confirmed the diagnosis of steroid-induced pancreatitis. Supportive care and cessation of the offending drug led to the resolution of symptoms. As steroids are used as part of the treatment of most COVID-19 patients, this case suggests the need to consider this entity, as a delay in the diagnosis may result in complications and prolonged hospital stay.

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BACKGROUND: The analysis of plant material from Cannabis sativa L. has long been targeted on its main psychologically active metabolite, Δ9-tetrahydrocannabinol (THC). In addition to the diverse plant composition and medicinal interest in several cannabinoids, these compounds may also be related to the different characteristics of samples sold illegally. Currently, it is indisputable that other cannabinoids should also be considered in cannabis assays. Mass spectrometry has been used to identify and characterize substances in the most different scenarios, and knowing the analyte fragmentation profile is essential for characterizing samples of diverse origin. OBJECTIVE: In this work, flow injection analysis-tandem mass spectrometry with electrospray ionization (FIA-ESI-MS/MS) in positive and negative modes was used to evaluate the fragmentation profiles of eight cannabinoids commonly found in cannabis samples: THC, tetrahydrocannabinolic acid, Δ8-tetrahydrocannabinol, cannabidiol, cannabidiolic acid, cannabigerol, cannabigerolic acid and cannabinol. METHODS: By exploring the fragmentation data from mass spectrometry, the samples were classified using a chemometric model of partial least squares discriminant analysis (PLS-DA). RESULTS: When ESI in negative mode is used with adequate collision energies, it is possible to identify differences in the fragmentation of isomers. Based on that, chemometric tools were employed to classify different samples. The PLS-DA applied to FIA-ESI-MS/MS data yielded satisfactory classification. CONCLUSION: Thus, the results presented can be applied as a preliminary tool in the analysis of unknown samples, guiding more accurate investigations in terms of chemical composition. HIGHLIGHTS: This study of the cannabinoid fragmentation pattern by flow injection MS showed that cannabinoids can be distinguished by their fragmentation spectra after negative electrospray ionization. Multivariate data analysis (PLS-DA) allowed classification of different cannabis samples.

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INTRODUCTION: The presence of anabolic-androgenic steroids (AAS) in illegal commercial products has been pointed as a global threat for public health. Due the correlation with adverse toxicological effects, there is a growing interest in the implementation of straightforward methods for the determination of AAS in seized products. This work exploited the development of a mass spectrometry approach to characterize the illegal oil formulations containing AAS. METHODS: The optimization of sample preparation was performed through a simplex-centroid design and the best condition was described as follow: an aliquot of 5 µL of sample were added with 995 µL of acetonitrile and water (75:25, v/v). The solution was vortexed and centrifuged. After that, 10 µL of supernatant were added with 35 µL of acetonitrile and water and internal standard (testosterone-d3, 1.25 ng). An aliquot of 5 µL was injected into the analytical system. RESULTS: The method developed was validated and successfully applied in 115 seized samples. Testosterone and its esters had the highest incidence, found in more than 50% of the samples. Besides that, drugs such as boldenone, methandienone, and trenbolone have also been found, where the low quality of the samples was evidenced by the wide variation in the concentration of the drugs, always quantified in sub-doses. Finally, at least one AAS was detected in each sample analyzed. The statistical results were grouped by principal components analysis, to better understand the profile of the seized samples. CONCLUSION: This work successfully established a fast and simple method for determination of AAS and can be applied to verify the profile of seized samples.

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A set of synthetic data, of antibacterial evaluation against gram-positive bacteria, as well as, the interaction of bacterial with lipid-core nanocapsules containing fusidic acid is presented here. In this data set, the analytical data are detailed; serial microdilution; nanoparticle tracking analysis; transmission electron microscopy; minimum inhibitory concentration; diameter size and zeta potential, and infra-red of the formulations before and after contact with bacteria.

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RESUMO O plantão psicológico é uma modalidade de atenção clínica em psicologia que disponibiliza atendimentos imediatos sem restrição de demanda. Ainda, o trabalho especializado oferecido pelo psicólogo consegue identificar os recursos pessoais do cliente para lidar com sua demanda e promover sua saúde sem necessidade de assistência intensiva. Para os demais casos, encaminhamentos e orientações permitem acionar outros serviços apropriados. Este trabalho teve como objetivo identificar e compreender as intervenções empregadas por um plantonista. A partir de análise de conteúdo de registros documentais de seis casos atendidos na modalidade de plantão psicológico realizado em uma clínica-escola e utilizando as matrizes teóricas da psicologia humanista-fenomenológica, foram identificadas e discutidas três unidades significativas a respeito das intervenções empregadas, nomeadas de reflexão, cuidado e explicação. Foi possível, então, relacionar as intervenções a uma facilitação de processo terapêutico e de ajuda ao cliente, encaminhando-o para um posicionamento mais pessoal e consciente. Houve a configuração de um ambiente de empatia e de aceitação incondicional em que os afetos puderam ser recebidos pelo plantonista com uma postura coerente e sensível. Somado a isso, foi possível desenvolver uma relação de aproximação entre o cliente e suas experiências, favorecendo ressignificações e maior consciência sobre seus modos de estar no mundo, logo uma condição mais autônoma e autêntica de existência. Por fim, algumas contribuições foram apresentadas e alguns temas centrais problematizados para dar corpo e movimento às pesquisas acerca do plantão psicológico.

RESUMEN La guardia psicológica es una modalidad de atención clínica en psicología que ofrece atendimientos inmediatos sin restricción de demanda. Además, el trabajo especializado ofrecido por el psicólogo logra identificar los recursos personales del cliente para lidiar con su demanda y promover su salud sin necesidad de asistencia intensiva. Para los demás casos, las remisiones y las orientaciones permiten accionar otros servicios apropiados. En esta investigación se tuvo como objetivo identificar y entender las intervenciones empleadas por un psicólogo de guardia. A partir de análisis de contenido de registros documentales de seis casos atendidos en la modalidad de guardia psicológica realizado en una escuela clínica y utilizando el enfoque de la psicología humanista-fenomenológica, fueron identificadas y discutidas tres unidades significativas respecto de las intervenciones empleadas, denominadas de reflexión, cuidado y explicación. Es posible, entonces, relacionar las conductas a una facilitación de proceso terapéutico y de ayuda al cliente, encaminándolo hacia un posicionamiento más personal y consciente. Hubo la configuración de un ambiente de empatía y de consideración positiva incondicional en que los afectos pudieron ser recibidos por el psicólogo de guardia con una postura coherente y sensible. Al sumado a ello, fue posible desarrollar una relación de acercamiento entre el cliente y sus experiencias, favoreciendo resignificaciones y mayor conciencia sobre sus modos del estar en el mundo, luego una condición más autómata y auténtica de existencia. Por último, algunas contribuciones fueron presentadas y algunos temas centrales problematizados para dar cuerpo y movimiento a las investigaciones acerca de la guardia psicológica.

ABSTRACT Psychological duty is a modality of clinical attention in psychology that makes available immediate appointments without restriction of requests. In addition, the specialized work offered by the psychologist is able to identify the personal resources of the client in order to deal with their request, and to promote their health without the need for intensive care. For the balance of the other cases, referral reports and guidance enable the activation of other appropriate services. This work aimed to identify and to understand the interventions employed by a psychologist on duty. Starting from the content cnalysis of records of six cases attended by the psychological duty schedule performed in a school-clinic, and by the use of the humanistic-phenomenological approach in psychology, three categories were identified and discussed regarding the interventions employed, namely reflections, care, and explanation. Thus, it was possible to relate the actions to a facilitator of the therapeutic process and help the attended person, leading them to a more personal and aware position. There is a setting of an empathic environment, and of unconditional positive regard in which the affections could be received by the psychologist on duty from a coherent and sensible posture. Added to this, it was possible to develop a proximity relationship between the attended person and their life experiences, favoring resignifications and a greater awareness of their ways of being in the world, so, a more autonomous and authentic condition of existence. Finally, some contributions were presented, and some core topics problematised in order to embody and give movement to the research about the psychological duty.

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An ESI-MS/MS method through direct infusion was validated for quantitative analysis of meropenem powder for injection. The validation parameters were established in a rapid analysis of 30 s. Drug stability was studied through the submission to stress testing, resulting on four degradation products. Under hydrolytic conditions, in acid, neutral and alkaline media, the major degradation product was formed through the cleavage of the ß-lactam ring. Oxidation of the drug using H2O2 (3%) showed the formation of two degradation products from a decarboxylation reaction and N-oxide formation. Under high humidity conditions, there was detected a dimer product. The stability of meropenem after reconstitution was studied in conditions that simulate its clinical use. In samples reconstituted and diluted in infusion fluids, an extensive degradation was observed. At room temperature meropenem maintained its content > 90% for up to 4 h when prepared in 5% glucose and for up to 12 h when prepared in 0.9% NaCl. Through ESI-MS/MS analyzes it was observed a degradation product formed by ß-lactam ring cleavage, detected in all conditions studied. It was also identified a degradation product formed only in 5% glucose, generated by the hydrolysis of ß-lactam followed by the attachment of a glucose molecule to the nitrogen of the pyrrolidine ring. In general, all the results obtained in the stability studies contribute to the knowledge about this antibiotic and future candidates of this class.

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OBJECTIVE: To evaluate the accuracy of percutaneous transhepatic biliary biopsy (PTBB) in patients with suspected biliary obstruction. MATERIALS AND METHODS: This was a retrospective analysis of 18 patients with obstructive jaundice who underwent PTBB. In each patient, three to ten fragments were collected from the lesion. The final diagnosis was confirmed in the pathology report. We also reviewed analyses of the results of laboratory tests performed before the procedure, as well as the Bismuth classification, clinical outcome, complications occurring during the procedure, access route, and materials used. RESULTS: Technical success was achieved in 100% of the PTBB procedures. Among the 18 patients clinically diagnosed with bile duct stenosis, the pathological analysis confirmed that diagnosis in 17. In one case, the pathological findings were considered false-negative. The predominant tumor was cholangiocarcinoma (seen in 50% of the cases). Sixteen of the procedures (88.9%) were performed without complications. Transient hemobilia occurred in one case, and cholangitis occurred in another. CONCLUSION: PTBB is a safe, viable, simple technique with a high rate of true-positive results for the definitive diagnosis of obstructive jaundice.

OBJETIVO: Avaliar a precisão diagnóstica da colangiobiópsia trans-hepática percutânea (CBTP) em pacientes com suspeita de obstrução biliar. MATERIAIS E MÉTODOS: Análise retrospectiva de 18 pacientes apresentando icterícia obstrutiva foram submetidos a CBTP. Em cada paciente, 3 a 10 fragmentos foram coletados da lesão. O diagnóstico final foi confirmado por relatório anatomopatológico. Adicionalmente, foram registrados a análise laboratorial antes do procedimento, a classificação de Bismuth, o desfecho clínico, as intercorrências durante o procedimento, a via de acesso e os materiais utilizados. RESULTADOS: A CBTP apresentou sucesso técnico em 100% dos casos. Dos 18 pacientes clinicamente diagnosticados com estenose biliar, 17 receberam diagnóstico patológico positivo. Em um caso os achados patológicos foram considerados falso-negativos. O colangiocarcinoma foi a neoplasia predominante (50%). Dezesseis (88,9%) procedimentos foram realizados sem intercorrências. Hemobilia transitória ocorreu em um caso e colangite em outro caso isolado. CONCLUSÃO: A CBTP é uma técnica segura, viável e simples, com alta taxa de verdadeiro-positivos para o diagnóstico definitivo de causas de icterícia obstrutiva.

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Abstract Objective: To evaluate the accuracy of percutaneous transhepatic biliary biopsy (PTBB) in patients with suspected biliary obstruction. Materials and methods: This was a retrospective analysis of 18 patients with obstructive jaundice who underwent PTBB. In each patient, three to ten fragments were collected from the lesion. The final diagnosis was confirmed in the pathology report. We also reviewed analyses of the results of laboratory tests performed before the procedure, as well as the Bismuth classification, clinical outcome, complications occurring during the procedure, access route, and materials used. Results: Technical success was achieved in 100% of the PTBB procedures. Among the 18 patients clinically diagnosed with bile duct stenosis, the pathological analysis confirmed that diagnosis in 17. In one case, the pathological findings were considered false-negative. The predominant tumor was cholangiocarcinoma (seen in 50% of the cases). Sixteen of the procedures (88.9%) were performed without complications. Transient hemobilia occurred in one case, and cholangitis occurred in another. Conclusion: PTBB is a safe, viable, simple technique with a high rate of true-positive results for the definitive diagnosis of obstructive jaundice.

Resumo Objetivo: Avaliar a precisão diagnóstica da colangiobiópsia trans-hepática percutânea (CBTP) em pacientes com suspeita de obstrução biliar. Materiais e Métodos: Análise retrospectiva de 18 pacientes apresentando icterícia obstrutiva foram submetidos a CBTP. Em cada paciente, 3 a 10 fragmentos foram coletados da lesão. O diagnóstico final foi confirmado por relatório anatomopatológico. Adicionalmente, foram registrados a análise laboratorial antes do procedimento, a classificação de Bismuth, o desfecho clínico, as intercorrências durante o procedimento, a via de acesso e os materiais utilizados. Resultados: A CBTP apresentou sucesso técnico em 100% dos casos. Dos 18 pacientes clinicamente diagnosticados com estenose biliar, 17 receberam diagnóstico patológico positivo. Em um caso os achados patológicos foram considerados falso-negativos. O colangiocarcinoma foi a neoplasia predominante (50%). Dezesseis (88,9%) procedimentos foram realizados sem intercorrências. Hemobilia transitória ocorreu em um caso e colangite em outro caso isolado. Conclusão: A CBTP é uma técnica segura, viável e simples, com alta taxa de verdadeiro-positivos para o diagnóstico definitivo de causas de icterícia obstrutiva.

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Carbapenems show recognized instability in aqueous solutions; therefore some care must be taken in their handling and preparation and their use in the hospital environment. The stability and degradation products of imipenem were investigated from conditions that simulate its clinical use. For this, a simple stability-indicating method by HPLC-DAD was validated with a focus on the quantitation of drug concentration remaining from infusion solutions (sodium chloride 0.9% and glucose 5%). The degradation products formed were identified by high-resolution mass spectrometry (ESI-Q-TOF-MS/MS), with detection of the [M + H]+ ions at m/z 318 (DP-1), m/z 599 (DP-2) and m/z 658 (DP-3). The most probable elemental compositions were obtained with a high degree of confidence, where the error between the masses observed and calculated was 1.25 ppm for DP-1, -0.33 ppm for DP-2 and 1.82 ppm for DP-3. The DP-1 degradation product resulted from cleavage of the ß-lactam ring; DP-2 corresponded to the drug dimer; and DP-3 was generated from the interaction between imipenem and cilastatin. The proposed method provides a safe and reliable alternative for the quantitation of imipenem, and the stability data obtained by ESI-Q-TOF help in understanding the drug behavior under the conditions of clinical use.

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The antipsychotic paliperidone was investigated with a focus on stability, degradation impurities and kinetics reaction profile. Osmotic tablets 3 mg (OROS® ) were subjected to extraction in an ultrasonic bath and the resulting acidic solution was stressed by forced conditions. Degraded samples were monitored by HPLC-DAD in different storage times for acidic and alkaline hydrolysis, oxidation, heat and photolysis. Photolysis was shown to be a strong degradation factor, with a drug content of 24.64% remaining after 24 h. Oxidation (H2 O2 18%) caused a slow decomposition, with a drug content of 83.49% remaining after 72 h. Through kinetics graphics, first-order reactions were found for oxidation, heat and photolysis. By UPLC-MS analysis, the degraded matrix could be investigated for identification of impurities with m/z 445.3128, m/z 380.8906, m/z 364.9391, m/z 232.9832 and m/z 217.0076, allowing the identification of derivatives N-oxide and with modifications in the lactam, benzisoxazole and pyrimidine rings. Paliperidone in liquid state, like analytical solutions or formulation, must be carefully handled to avoid drug exposure, specially in storage conditions.

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