Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 279
Filtrar
1.
Anal Chim Acta ; 1107: 113-126, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32200885

RESUMO

Quadrupole based mass spectrometry based detection has experienced enormous improvements in terms of sensitivity over the last centuries. This development has not been equally matched with improvements in selectivity. Hence, the use of unit mass based MS/MS transitions or high resolution (HRMS) based extracted ion chromatograms is gradually becoming insufficient in the field of high sensitivity multi-residue analysis (e.g. pesticides in food). As a consequence, commercial instruments hyphenating ion mobility (IMS) with low or high resolution mass spectrometry based detection have appeared. The use of such an additional (frequently claimed to be orthogonal) dimension is intended to increase selectivity. In addition, IMS derived collision cross section (CCS) has been proposed to be used as an additional identification point for the unambiguous identification of trace compounds in complex matrices. It is the topic of this paper to investigate the benefit of using such a hyphenated technique for trace analysis of small molecules in complex matrices. The potential of CCS to serve as additional identification point has been critically evaluated. Discussed are the effect of CCS data on false detects and missing detects of analytes present at trace levels. This involves the investigation of the physical resolving power provided by HRMS, IMS and chromatography as well as the correlation among these parameters (orthogonality). It is the conclusion that currently commercially available travelling wave and linear drift tube based IMS devices with a resolving power of up to 50 permit a reduction of false detects, yet this comes at the price of a higher likelihood of missing detects. The reduction of missing detects and the use of CCS as potential confirmatory information would require IMS resolving powers above 100.

2.
Urologe A ; 2020 Feb 04.
Artigo em Alemão | MEDLINE | ID: mdl-32020241

RESUMO

BACKGROUND: There is to date no convincing literature that has assessed the association between traumatic spinal cord injury (SCI) and the later development of urinary bladder cancer. The aim of this work is to present medical experts as well as the national accident insurance and the social courts decision-making aids based on the latest medical scientific knowledge, for assessment of this causal association. MATERIALS AND METHODS: A study conducted between April 1998 and March 2017 in the BG Trauma Hospital Hamburg forms the basis for the decision-making aids. Urinary bladder cancer was diagnosed in 32 out of 6432 treated outpatient and inpatient SCI patients. Furthermore, relevant published literature was taken into consideration for the decision-making aids. RESULTS: It was found that urinary bladder cancer in SCI patients occurs at a considerably younger age as compared to the general population, more frequently shows muscle invasive carcinoma with a higher grade at first diagnosis and a higher proportion of the more aggressive squamous cell carcinoma than that of the general population. Correspondingly, the survival time is extremely unfavorable. For medical experts a matrix was compiled where the various influencing factors, either for or against the recognition of an association between SCI and urinary bladder cancer, were weighted according to their relevance. CONCLUSION: The results showed that urinary bladder cancer in SCI patients differs considerably from that of able-bodied patients. These differences drastically shorten the survival time. A study on patients with spina bifida, i.e., a congenital spinal cord disorder, corroborates these observations. They indicate histopathological differences that have so far been intangible.

3.
HNO ; 68(2): 94-99, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31996933

RESUMO

Cancer stem cell (CSC)-related therapy resistance has become a new obstacle to the successful application of cancer treatment and head and neck squamous cell carcinoma (HNSCC) is no exception to this finding. Head and neck squamous cell carcinoma is highly immune-suppressive, and recently the immune suppression and invasion of HNSCC-CSCs have been characterized. These characteristics have received research and clinical attention because they would enable the stratification of patients into specific cancer subtypes and, consequently, the establishment of new therapeutic approaches with improved efficacy. This review discusses the feasibility of CSC-targeted strategies and their incorporation with nanotechnology to improve the efficacy of cancer immunotherapy.


Assuntos
Neoplasias de Cabeça e Pescoço , Imunoterapia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Linhagem Celular Tumoral , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Células-Tronco Neoplásicas , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia
4.
Urologe A ; 59(1): 65-71, 2020 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-31741004

RESUMO

Due to a safety alert issued by the US Food and Drug Administration (FDA) in 2011 for transvaginal mesh implants to treat female prolapse as a result of numerous reports of complications such as infection, chronic pain, dyspareunia, vaginal erosion, shrinkage and erosion into other organs nearly all industrial products have been withdrawn from the market in the meantime. The United Kingdom, Australia, and New Zealand extended warnings and prohibitions even on the implantation of midurethral slings (TVT, TOT). In view of these current international controversies regarding the use of implanted materials for the treatment of stress incontinence and prolapse and the lack of clear guidelines for the use of biomaterials, the opinion of the Working Group on Urological Functional Diagnostics and Female Urology should provide clarity. The Opinion is based on the SCENIHR Report of the "European Commission's Scientific Committee on Emerging and Newly Identified Health Risks", the "Consensus Statement of the European Urology Association and the European Urogynaecological Association on the Use of Implanted Materials for Treating Pelvic Organ Prolapse and Stress Urinary Incontinence" and in compliance with relevant EAU and national guidelines and the opinion of the Association for Urogynaecology and Plastic Pelvic Floor Reconstruction (AGUB eV). In addition, recommendations are given for the future handling of implants of slings and meshes for the treatment of stress incontinence and prolapse from a urologic viewpoint.


Assuntos
Prolapso de Órgão Pélvico/cirurgia , Slings Suburetrais/efeitos adversos , Telas Cirúrgicas/efeitos adversos , Incontinência Urinária por Estresse/cirurgia , Procedimentos Cirúrgicos Urológicos/instrumentação , Feminino , Alemanha , Humanos
5.
Anal Chim Acta ; 1054: 59-73, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-30712594

RESUMO

A new, relatively simple sample processing and detection workflow has been developed for the quantification and confirmation of banned growth-promoting substances in a wide variety of animal-based food products. The method covers all required compounds (belonging to the so-called A1, A3, A4 and B2f groups as termed by the relevant EU legislation) which are currently monitored by the official European community surveillance programs. The sample processing includes a thermal sample denaturation step, intended to prevent undesirable side-reactions during the following enzymatic deconjugation of covalently bound analytes. A pH-adjusted dual liquid/liquid-extraction produces sufficient clean extracts for a wide range of matrices (urine, muscle, liver, serum, full blood). The method has been validated using two hybrid quadrupole high-resolution mass spectrometers (Orbitrap and time-of-flight technology-based instruments). Full-scan data acquisition, interlaced with targeted modes (unit mass isolation of the precursors, followed by collision-induced fragmentation), produces sufficiently sensitive and selective detection of the analytes within all the validated matrices. The proposed method is an alternative to currently used methods that are restricted to a limited set of analytes and matrices.


Assuntos
Análise de Alimentos/métodos , Lactonas/análise , Espectrometria de Massas/métodos , Esteroides/análise , Estilbenos/análise , Métodos Analíticos de Preparação de Amostras , Animais , Concentração de Íons de Hidrogênio , Lactonas/química , Lactonas/isolamento & purificação , Extração Líquido-Líquido , Esteroides/química , Esteroides/isolamento & purificação , Estilbenos/química , Estilbenos/isolamento & purificação
7.
Urologe A ; 57(2): 155-163, 2018 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-28707096

RESUMO

BACKGROUND: Using the CE mark of therapeutic appliances is, on its own, not sufficient enough for their appropriate and effective application. In order to treat the patient successfully, not jeopardizing the success of the treatment, medical quality criteria for therapeutic appliances care are necessary to acceptably compensate for a patient's disabilities. OBJECTIVES: Medical quality criteria are formulated for the most frequently used urological aids and devices, considering hygienic requirements, international literature and the practical experience of physicians and nurses with regard to the care of patients with neurogenic urinary bladder dysfunction. METHODS: An expert group of urologists, surgeons, rehabilitation physicians and nurses has developed medical quality criteria via a structured consensus procedure. Developing these criteria, the group has taken into account current jurisprudence, the current resource directory of neurourological relevant aids, data from international literature and hygiene requirements. RESULTS: Medical quality requirements are discussed and defined for selected groups of urological devices (single use catheters, indwelling catheters, external catheters, urine bags, templates and diapers as well as devices for the electrostimulation of nerves). CONCLUSION: The presented quality requirements offer the possibility to stabilize quality of care with neurourological relevant therapeutic appliances. The catalogue of therapeutic appliances must be urgently updated. Urinal catheters for single use must be classified as an individual product group. Devices for anterior root stimulation and neuromodulation must be included in the resource directory. The incontinence severity classification needs to be reviewed.


Assuntos
Cateteres de Demora/normas , Bexiga Urinaria Neurogênica/reabilitação , Cateteres Urinários/normas , Consenso , Humanos , Incontinência Urinária
8.
Papillomavirus Res ; 4: 35-38, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29179867

RESUMO

It is well-established that immunocompromised people are at increased risk of HPV-related disease compared with those who are immunocompetent. Prophylactic HPV sub-unit vaccines are safe and immunogenic in immunocompromised people and it is strongly recommended that vaccination occur according to national guidelines. When delivered to immunocompromised populations, HPV vaccines should be given as a 3-dose regimen.


Assuntos
Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/administração & dosagem , Hospedeiro Imunocomprometido , Vacinas contra Papillomavirus/administração & dosagem , Vacinação/efeitos adversos , Adolescente , Criança , Feminino , Guias como Assunto , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/efeitos adversos , Humanos , Imunogenicidade da Vacina , Infecções por Papillomavirus/prevenção & controle , Infecções por Papillomavirus/virologia , Vacinas contra Papillomavirus/efeitos adversos , Vacinação/métodos
10.
Urologe A ; 56(12): 1539-1547, 2017 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-29079907

RESUMO

Surgery is often necessary after failure of conservative therapy for urinary incontinence. Guidelines recommend urodynamic studies before surgery. A distinction is made between non-invasive (uroflowmetry) and invasive methods (cystometry and pressure-flow study, if necessary as combined videourodynamics, as well as urethral pressure profile). All examinations serve to objectify and quantify the symptoms, to correctly assign symptoms to the pathophysiology and anatomy as well as to identify risk factors, which often have a significant influence on the success of surgical therapy. Given appropriate experience, complications and often significant sequelae of bladder dysfunction affecting the patient's quality of life and life expectancy can be recognized. Urodynamic studies are performed to help narrow down potential diagnoses, to develop therapeutic strategies, and to obtain prognostic parameters. The following article is intended to provide some support.


Assuntos
Incontinência Urinária/fisiopatologia , Incontinência Urinária/cirurgia , Urodinâmica/fisiologia , Idoso , Benzilatos/uso terapêutico , Terapia Combinada , Diagnóstico Diferencial , Feminino , Fidelidade a Diretrizes , Humanos , Masculino , Nortropanos/uso terapêutico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/cirurgia , Prostatectomia , Fatores de Risco , Slings Suburetrais , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/fisiopatologia , Bexiga Urinária Hiperativa/etiologia , Bexiga Urinária Hiperativa/fisiopatologia , Bexiga Urinária Hiperativa/cirurgia , Incontinência Urinária/etiologia , Incontinência Urinária por Estresse/etiologia , Incontinência Urinária por Estresse/fisiopatologia , Incontinência Urinária por Estresse/cirurgia , Gravação em Vídeo
11.
Gynecol Oncol ; 146(2): 327-333, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28511869

RESUMO

BACKGROUND: The morphological classification of high-risk endometrial cancer is of limited prognostic value. Recent attempts to stratify tumours according to molecular signatures have shown considerable promise. Here we attempted to further refine molecular classifications using markers of the p53 pathway. METHODS: We analysed the expression of p53 as well as three downstream markers of the p53 pathway, p21, mdm2 and phospho-p63 (pp63), by immunohistochemistry in a series of 114 endometrial cancers (86 endometrioid, 28 non-endometrioid subtype) with high-risk features (such as high tumour grade and deep myometrial invasion) and correlated results with clinical outcome. The Cancer Genome Atlas (TCGA) data were used to analyse TP63 mutations and copy-number alterations using cBioPortal. TP53 was silenced in two endometrial cancer cell lines to study its effect on p21 and p63. RESULTS: About half of the tumours showed a p53 mutant phenotype and there was a strong negative correlation with p21 expression. Being marker positive for pp63 or mdm2 was associated with a significantly increased likelihood of dying, [hazard ratios 5.93 (95% CI 2.37-7.27) and 7.48 (95% CI 3.04-9.39), respectively]. These findings were seen in both p53 wildtype and p53 mutant tumours. Only 11% of TCGA endometrial cancers had a functional TP63 alteration. Upon silencing of TP53, p21 expression was decreased in one cell line, but no effects on p63 were observed. CONCLUSION: Markers of the p53 pathway improve stratification of endometrial cancers and provide novel insights into the role of this pathway in the disease.


Assuntos
Adenocarcinoma de Células Claras/metabolismo , Carcinoma Endometrioide/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Neoplasias do Endométrio/metabolismo , Neoplasias Císticas, Mucinosas e Serosas/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Adenocarcinoma de Células Claras/genética , Adenocarcinoma de Células Claras/mortalidade , Adenocarcinoma de Células Claras/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Endometrioide/genética , Carcinoma Endometrioide/mortalidade , Carcinoma Endometrioide/patologia , Linhagem Celular Tumoral , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/mortalidade , Neoplasias do Endométrio/patologia , Feminino , Inativação Gênica , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Mutação , Gradação de Tumores , Invasividade Neoplásica , Neoplasias Císticas, Mucinosas e Serosas/genética , Neoplasias Císticas, Mucinosas e Serosas/mortalidade , Neoplasias Císticas, Mucinosas e Serosas/patologia , Fosfoproteínas , Prognóstico , Modelos de Riscos Proporcionais , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Adulto Jovem
12.
Neurocrit Care ; 27(3): 381-391, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28382509

RESUMO

BACKGROUND: Existing scoring systems for aneurysmal subarachnoid hemorrhage (SAH) patients fail to accurately predict patient outcome. Our goal was to prospectively study the Full Outline of UnResponsiveness (FOUR) score as applied to newly admitted aneurysmal SAH patients. METHODS: All adult patients presenting to Health Sciences Center in Winnipeg from January 2013 to July 2015 (2.5 year period) with aneurysmal SAH were prospectively enrolled in this study. All patients were followed up to 6 months. FOUR score was calculated upon admission, with repeat calculation at 7 and 14 days. The primary outcomes were: mortality, as well as dichotomized 1- and 6-month Glasgow Outcome Scale (GOS) and modified Rankin Scale (mRS) values. RESULTS: Sixty-four patients were included, with a mean age of 54.2 years (range 26-85 years). The mean FOUR score upon admission pre- and post-external ventricular drain (EVD) was 10.3 (range 0-16) and 11.1 (range 3-16), respectively. There was a statistically significant association between pre-EVD FOUR score (total, eye, respiratory and motor sub-scores) with mortality, 1-month GOS, and 6-month GOS/mRS (p < 0.05 in all). The day 7 total, eye, respiratory, and motor FOUR scores were associated with mortality, 1-month GOS/mRS, and 6-month GOS/mRS (p < 0.05 in all). The day 14 total, eye, respiratory, and motor FOUR scores were associated with 6-month GOS (p < 0.05 in all). The day 7 cumulative FOUR score was associated with the development of clinical vasospasm (p < 0.05). CONCLUSIONS: The FOUR score at admission and day 7 post-SAH is associated with mortality, 1-month GOS/mRS, and 6-month GOS/mRS. The FOUR score at day 14 post-SAH is associated with 6-month GOS. The brainstem sub-score was not associated with 1- or 6-month primary outcomes.


Assuntos
Escala de Coma de Glasgow , Escala de Resultado de Glasgow , Aneurisma Intracraniano/complicações , Índice de Gravidade de Doença , Hemorragia Subaracnóidea/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hemorragia Subaracnóidea/etiologia
13.
Urologe A ; 56(6): 785-792, 2017 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-28314966

RESUMO

BACKGROUND: Most patients with spinal cord injury (SCI) suffer from neurogenic lower urinary tract dysfunction (NLUTD), bowel dysfunction and sexual dysfunction. If these remain untreated, severe medical complications and serious limitations (restrictions) in quality of life are imminent. OBJECTIVES: In the long term, there are considerable differences in the treatment results of highly specialized centers versus other treatment facilities. MATERIALS AND METHODS: Against this background, a consensus-based guideline, according to the AWMF (Association of the Scientific Medical Societies in Germany) criteria (S2k), was developed by the neuro-urology working group of the DMPG (German-Speaking Medical Society of Paraplegia). RESULTS: The guideline defines the principles and objectives of the neuro-urological care of patients with SCI and discusses in detail the principles of diagnosis and therapy of NLUTD. The need for video-urodynamic studies as a basis for the classification of the NLUTD and as a foundation for the development of a treatment strategy is emphasized. Both conservative and surgical therapy options and their indications are explained in detail. Possible complications and their prevention in the long-term course of SCI are presented with a particular consideration of the specific features of urinary tract infections and autonomic dysreflexia. Finally, the principles of the provision of urological appliances are discussed. CONCLUSIONS: The presented S2k guideline provides the current standards in the neuro-urological care of patients with NLUTD due to SCI. Their consistent implementation both in the acute and chronic phase as well as in the context of lifelong surveillance of SCI patients should prevent the impending complications of NLUTD.


Assuntos
Técnicas de Diagnóstico Neurológico/normas , Técnicas de Diagnóstico Urológico/normas , Guias de Prática Clínica como Assunto , Traumatismos da Medula Espinal/diagnóstico , Bexiga Urinaria Neurogênica/diagnóstico , Bexiga Urinaria Neurogênica/etiologia , Urologia/normas , Diagnóstico Diferencial , Medicina Baseada em Evidências , Alemanha , Humanos , Traumatismos da Medula Espinal/complicações , Resultado do Tratamento
15.
Urologe A ; 55(12): 1553-1563, 2016 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-27725995

RESUMO

BACKGROUND: The provision of urological appliances for patients with neurogenic lower urinary tract dysfunction (NLUTD) is essential. Hitherto existing standard guidelines for the estimation of monthly material requirements are based solely on estimates. OBJECTIVE: The goal of this work was to define the objective and subsequently subjective requirements for urological appliances on a scientifically validated basis. MATERIALS AND METHODS: Data concerning bladder management and daily consumption of urological appliances for patients with NLUTD were collected through a standardized survey at six different centers in Germany during the period of October to December 2014 and statistically evaluated. RESULTS: In all, 767 patient records were analyzed: 543 men and 221 woman (N/A = 3). The daily disposable catheter consumption of 577 patients who exclusively used intermittent catheterization was 5.13. Patients who used other means of bladder emptying (n = 31) in addition to catheterization consumed on average 3.17 catheters. The margin of deviation was larger for children. Of the 608 patients with intermittent catheterization, 94 (15.5 %) required additional paddings as absorbent aids (on average 2.29 paddings per day), 34 patients (5.6 %) additionally used pants (2.55 per day) and 46 patients (7.6 %) utilized condom catheters (3.81 per day) between catheterization. Among all surveyed patients, 126 (16.4 %) used paddings (5.03 per day) and 51 patients (6.6 %) pants (3.03 per day). Of all male respondents 82 (15.1 %) used condom catheters (2.80 urinary sheaths per day). CONCLUSION: Applying twice the standard deviation of the mean as a measure of assessing the objective requirement of urological appliances and aids for adult patients with NLUTD allows the following daily thresholds to be defined: 1-9 disposable catheters, 0-7 urinary sheaths, 1-9 paddings and 0-7 pants. These thresholds can serve as a basis for estimating the subjective need. They allow for a scientifically validated benchmark for an economically feasible and patient-tailored supply with urological aids and appliances. Individually required appliances and aids have to be recognized. Verifiable quality standards need to be developed.


Assuntos
Sintomas do Trato Urinário Inferior/epidemiologia , Sintomas do Trato Urinário Inferior/reabilitação , Bexiga Urinaria Neurogênica/epidemiologia , Bexiga Urinaria Neurogênica/reabilitação , Cateteres Urinários/estatística & dados numéricos , Revisão da Utilização de Recursos de Saúde , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Equipamentos Descartáveis/classificação , Equipamentos Descartáveis/estatística & dados numéricos , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Determinação de Necessidades de Cuidados de Saúde , Preferência do Paciente/estatística & dados numéricos , Estudos Retrospectivos , Distribuição por Sexo , Resultado do Tratamento , Cateteres Urinários/classificação , Adulto Jovem
16.
Aktuelle Urol ; 47(4): 305-9, 2016 08.
Artigo em Alemão | MEDLINE | ID: mdl-27500848

RESUMO

The syndrome of overactive bladder (OAB) with the symptoms of frequency, urgency and nocturia is often seen. After the diagnosis has been made by careful exclusion of other conditions, there are different symptomatic treatment strategies available. These include drug treatment as well as minimally invasive local surgical treatments and treatments which intervene with the control of the bladder by modulating central nervous areas. Alternative methods such as acupuncture may help in individual cases; the placebo effect is high and there is a lack of controlled studies.


Assuntos
Noctúria , Bexiga Urinária Hiperativa/tratamento farmacológico , Humanos
17.
Rapid Commun Mass Spectrom ; 30(7): 791-9, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26969920

RESUMO

RATIONALE: Elucidation of the elemental compositions of unknown compounds (e.g., in metabolomics) generally relies on the availability of accurate masses and isotopic ratios. This study focuses on the information provided by the abundance ratio within a product ion pair (monoisotopic versus the first isotopic peak) when isolating and fragmenting the first isotopic ion (first isotopic mass spectrum) of the precursor. METHODS: This process relies on the capability of the quadrupole within the Q Orbitrap instrument to isolate a very narrow mass window. Selecting only the first isotopic peak (first isotopic mass spectrum) leads to the observation of a unique product ion pair. The lighter ion within such an isotopologue pair is monoisotopic, while the heavier ion contains a single carbon isotope. The observed abundance ratio is governed by the percentage of carbon atoms lost during the fragmentation and can be described by a hypergeometric distribution. RESULTS: The observed carbon isotopologue abundance ratio (product ion isotopologue pattern) gives reliable information regarding the percentage of carbon atoms lost in the fragmentation process. It therefore facilitates the elucidation of the involved precursor and product ions. Unlike conventional isotopic abundances, the product ion isotopologue pattern is hardly affected by isobaric interferences. Furthermore, the appearance of these pairs greatly aids in cleaning up a 'matrix-contaminated' product ion spectrum. CONCLUSIONS: The product ion isotopologue pattern is a valuable tool for structural elucidation. It increases confidence in results and permits structural elucidations for heavier ions. This tool is also very useful in elucidating the elemental composition of product ions. Such information is highly valued in the field of multi-residue analysis, where the accurate mass of product ions is required for the confirmation process. Copyright © 2016 John Wiley & Sons, Ltd.

18.
Rapid Commun Mass Spectrom ; 30(8): 1087-95, 2016 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-27003046

RESUMO

RATIONALE: The intrascan dynamic range of modern Orbitrap instrumentation is specified to reach 1:5000, while the interscan dynamic range is significantly larger due to the utilization of the automatic gain control feature. There are some applications (e.g. residue analysis in complex matrices, metabolomics or structural elucidation) where a wider intrascan dynamic range is desirable. METHODS: The Application Programming Interface (API) of the Q Exactive Orbitrap mass spectrometer has been used to program a customized scan in order to cover a larger intrascan dynamic range. Different approaches were used, which were all based on the variation of the isolation time of low-abundance versus high-abundance mass range segments. The differently attenuated mass range segments isolated by the quadrupole were sequentially forwarded to the C-trap. Finally, the accumulated mass segments were measured within the Orbitrap analyzer. RESULTS: The spectra obtained by the customized scans show an enlarged dynamic range. This has been demonstrated by monitoring the higher isotope mass peaks (first and second isotope) of a low intensity analyte. Furthermore, a practical application (veterinary drugs in bovine kidney) has been investigated with the proposed customized scan. Analytes eluting within the retention time region of very intense matrix peaks (e.g. peptides) showed improved detectability when utilizing the customized scan. CONCLUSIONS: The extension of the intrascan dynamic range by a customized scan is helpful when analyzing residues which happen to elute together with a dominating matrix peak or within a high ion abundance region (e.g. dead volume). Furthermore, this feature helps in the process of determining the elemental composition of compounds by permitting the investigation of low-abundance ions (e.g. belonging to the isotopic fine structure of the investigated compound).

19.
Reprod Sci ; 22(12): 1632-42, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26169037

RESUMO

Endometriosis is a prevalent benign disease, despite sharing several similarities with malignancies, such as the possibility of lymphatic spread. In malignancies, chemokines play a sovereign role in the process of metastasis. Metastasis-related chemokine axes have not yet been assessed in deep-infiltrating endometriosis (DIE), and this investigation was the aim of our study. The expression of these chemokines was investigated by immunohistochemistry in rectovaginal DIE lesions and in matched pelvic sentinel lymph nodes (PSLNs) of patients with endometriosis (n = 27), and their expression in the eutopic endometrium (EE) of endometriosis-free women (n = 20) was used as controls. Their staining pattern in rectovaginal DIE, in endometriotic lesions affecting the PSLN as well as in the EE of patients without endometriosis was characterized for the first time. Overall, these chemokines were highly expressed in DIE and endometriosis in PSLN. Chemokines might be involved in the spread of endometriosis and should be further investigated.


Assuntos
Movimento Celular , Quimiocinas/análise , Endometriose/metabolismo , Endométrio/química , Imuno-Histoquímica , Linfonodos/química , Biópsia de Linfonodo Sentinela , Adulto , Biomarcadores/análise , Endometriose/patologia , Endométrio/patologia , Feminino , Humanos , Linfonodos/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
20.
Anal Chim Acta ; 862: 41-52, 2015 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-25682427

RESUMO

An ultra-high performance liquid chromatography based method, coupled to high resolution mass spectrometry (UHPLC-HRMS), was developed to permit the detection and quantification of various nitrofuran and chloramphenicol residues in a number of animal based food products. This method is based on the hydrolysis of covalently bound metabolites and derivatization with 2-nitrobenzaldehyde. Clean-up is achieved by a liquid/liquid and a reversed phase/solid phase extraction. Not only are the four conventional nitrofurans (nitrofurantoin, furazolidone, nitrofurazone and furaltadone) detected, but also nifursol, nitrovin and nifuroxazide. Furthermore, an underivatizable nitrofuran (nifurpirinol) and another banned drug (chloramphenicol) can be quantified as well. The compounds are detected in the form of their precursor ions, [M+H](+) and [M-H](-), respectively. The mass resolving power of 70,000 FWHM, and the applied mass window ensure sufficient selectivity and sensitivity. Confirmation is obtained by monitoring the HRMS resolved product ions which were derived from the unit-mass resolved precursor ions. The multiplexing capability of the utilized Orbitrap instrument provides not only highly selective, but also sensitive confirmatory signals. This method has been validated according to the CD 2002/657/EC for the following matrices: muscle, liver, kidney, fish, honey, eggs and milk.


Assuntos
Cloranfenicol/análise , Cloranfenicol/química , Espectrometria de Massas , Nitrofuranos/análise , Nitrofuranos/química , Espectrometria de Massas em Tandem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA