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1.
J Neuroinflammation ; 14(1): 123, 2017 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-28645295

RESUMEN

BACKGROUND: Autoantibodies, in particular those against aquaporin-4 and myelin-oligodendrocyte glycoprotein (MOG), aid as biomarkers in the differential diagnosis of demyelination. Here, we report on discovery of autoantibodies against flotillin in patients with multiple sclerosis (MS). METHODS: The target antigen was identified by histo-immunoprecipitation using the patients' sera and cryosections of rat or pig cerebellum combined with mass spectrometrical analysis. Correct identification was ascertained by indirect immunofluorescence and neutralization tests using the target antigens recombinantly expressed in HEK293 cells. RESULTS: Serum and CSF of the index patient produced a fine-granular IgG indirect immunofluorescence staining of the hippocampal and cerebellar molecular layers. Flotillin-1 and flotillin-2 were identified as target autoantigens. They also reacted with recombinant human flotillin-1/2 co-expressed in HEK293 cells, but not with the individual flotillins in fixed- and live-cell assays. Moreover, neutralization using flotillin-1/2, but not the single flotillins, abolished the tissue reactivity of patient serum. Screening of 521 patients, for whom anti-aquaporin-4 testing was requested and negative, revealed 8 additional patients with anti-flotillin-1/2 autoantibodies. All eight were negative for anti-MOG. Six patients ex post fulfilled the revised McDonald criteria for MS. Vice versa, screening of 538 MS sera revealed anti-flotillin-1/2 autoantibodies in eight patients. The autoantibodies were not found in a cohort of 67 patients with other neural autoantibody-associated syndromes and in 444 healthy blood donors. CONCLUSIONS: Autoantibodies against the flotillin-1/2 heterocomplex, a peripheral membrane protein that is involved in axon outgrowth and regeneration of the optic nerve, are present in 1-2% of patients with bona fide MS.


Asunto(s)
Autoanticuerpos/metabolismo , Microdominios de Membrana/metabolismo , Proteínas de la Membrana/metabolismo , Esclerosis Múltiple/metabolismo , Adulto , Animales , Autoanticuerpos/inmunología , Femenino , Células HEK293 , Humanos , Masculino , Microdominios de Membrana/inmunología , Proteínas de la Membrana/inmunología , Persona de Mediana Edad , Esclerosis Múltiple/inmunología , Esclerosis Múltiple/patología , Ratas , Porcinos
2.
J Neurol ; 264(3): 453-466, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28005176

RESUMEN

BACKGROUND: It has long been known that the majority of patients with multiple sclerosis (MS) display an intrathecal, polyspecific humoral immune response to a broad panel of neurotropic viruses. This response has measles virus, rubella virus and varicella zoster virus as its most frequent constituents and is thus referred to as the MRZ reaction (MRZR). OBJECTIVE: Re-evaluation of the specificity of MRZR as a marker of MS. METHODS: Structured review of the existing English-, German- and Spanish-language literature on MRZR testing, with evaluation of MRZR in a cohort of 43 unselected patients with MS and other neurological diseases as a proof of principle. RESULTS: A positive MRZ reaction, defined as a positive intrathecal response to at least two of the three viral agents, was found in 78% of MS patients but only in 3% of the controls (p < 0.00001), corresponding to specificity of 97%. Median antibody index values were significantly lower in non-MS patients (measles, p < 0.0001; rubella, p < 0.006; varicella zoster, p < 0.02). The 30 identified original studies on MRZR reported results from 1478 individual MRZR tests. A positive MRZR was reported for 458/724 (63.3%) tests in patients with MS but only for 19/754 (2.5%) tests in control patients (p < 0.000001), corresponding to cumulative specificity of 97.5% (CI 95% 96-98.4), cumulative sensitivity of 63.3% (CI 95% 59.6-66.8) (or 67.4% [CI 95% 63.5-71.1] in the adult MS subgroup), a positive likelihood ratio of 25.1 (CI 95% 16-39.3) and a negative likelihood ratio of 0.38 (CI 95% 0.34-0.41). Of particular note, MRZR was absent in 52/53 (98.1%) patients with neuromyelitis optica or MOG-IgG-positive encephalomyelitis, two important differential diagnoses of MS. CONCLUSION: MRZR is the most specific laboratory marker of MS reported to date. If present, MRZR substantially increases the likelihood of the diagnosis of MS. Prospective and systematic studies on the diagnostic and prognostic impact of MRZR testing are highly warranted.


Asunto(s)
Anticuerpos Antivirales/líquido cefalorraquídeo , Herpesvirus Humano 3/inmunología , Virus del Sarampión/inmunología , Esclerosis Múltiple/líquido cefalorraquídeo , Virus de la Rubéola/inmunología , Biomarcadores/líquido cefalorraquídeo , Humanos , Esclerosis Múltiple/virología
3.
Praxis (Bern 1994) ; 100(6): 367-71, 2011 Mar 16.
Artículo en Alemán | MEDLINE | ID: mdl-21412749

RESUMEN

Mollaret's meningitis is a recurrent meningitis, usually caused by Herpes simplex virus type 2. Symptoms are typical for meningitis, but other causes for recurrent and chronic meningitis have to be excluded in the cerebrospinal fluid. Usually Mollaret's meningitis is a benign form of meningitis without sequelae. There are no evidence-based data about therapy because of few reported cases.


Asunto(s)
Trastornos de Cefalalgia/etiología , Herpes Simple/diagnóstico , Herpesvirus Humano 2 , Meningitis Aséptica/diagnóstico , Meningitis Viral/tratamiento farmacológico , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Recurrencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
4.
Oncogene ; 30(22): 2547-57, 2011 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-21278786

RESUMEN

There is a strong rationale to therapeutically target the phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway in breast cancer since it is highly deregulated in this disease and it also mediates resistance to anti-HER2 therapies. However, initial studies with rapalogs, allosteric inhibitors of mTORC1, have resulted in limited clinical efficacy probably due to the release of a negative regulatory feedback loop that triggers AKT and ERK signaling. Since activation of AKT occurs via PI3K, we decided to explore whether PI3K inhibitors prevent the activation of these compensatory pathways. Using HER2-overexpressing breast cancer cells as a model, we observed that PI3K inhibitors abolished AKT activation. However, PI3K inhibition resulted in a compensatory activation of the ERK signaling pathway. This enhanced ERK signaling occurred as a result of activation of HER family receptors as evidenced by induction of HER receptors dimerization and phosphorylation, increased expression of HER3 and binding of adaptor molecules to HER2 and HER3. The activation of ERK was prevented with either MEK inhibitors or anti-HER2 monoclonal antibodies and tyrosine kinase inhibitors. Combined administration of PI3K inhibitors with either HER2 or MEK inhibitors resulted in decreased proliferation, enhanced cell death and superior anti-tumor activity compared with single agent PI3K inhibitors. Our findings indicate that PI3K inhibition in HER2-overexpressing breast cancer activates a new compensatory pathway that results in ERK dependency. Combined anti-MEK or anti-HER2 therapy with PI3K inhibitors may be required in order to achieve optimal efficacy in HER2-overexpressing breast cancer. This approach warrants clinical evaluation.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Inhibidores de Proteínas Quinasas/uso terapéutico , Receptor ErbB-2/metabolismo , Neoplasias de la Mama/enzimología , Línea Celular Tumoral , Femenino , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor ErbB-3/metabolismo , Serina-Treonina Quinasas TOR/antagonistas & inhibidores
5.
J Neurol Neurosurg Psychiatry ; 79(10): 1134-6, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18270237

RESUMEN

BACKGROUND: A polyspecific, intrathecal humoral immune response against neurotropic viruses such as measles, rubella and varicella zoster virus (MRZ reaction, MRZR) is present in 80-100% of patients with multiple sclerosis (MS), but has not to date been evaluated in patients with neuromyelitis optica (NMO). AIMS: To evaluate whether MRZR distinguishes NMO and MS. METHODS: 20 patients with NMO and 42 with MS were included. The intrathecal synthesis of antibodies against measles, rubella and varicella zoster virus was detected by calculation of the respective antibody indices (AI). RESULTS: A positive MRZ reaction, as defined by a combination of at least two positive AIs, was found in 37/42 MS, but in only 1/20 NMO patients (p<0.0001). Median AI values differed significantly between the groups (p<0.0005). CONCLUSIONS: The polyspecific antiviral humoral immune response characteristic for MS is widely missing in NMO, irrespective of the NMO-IgG status of the patients. Our findings further strengthen the case for NMO being pathologically distinct from MS.


Asunto(s)
Anticuerpos Antivirales/inmunología , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/inmunología , Neuromielitis Óptica/diagnóstico , Neuromielitis Óptica/inmunología , Adulto , Anciano , Varicela/inmunología , Diagnóstico Diferencial , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Imagen por Resonancia Magnética , Masculino , Sarampión/inmunología , Persona de Mediana Edad , Nervio Óptico/inmunología , Nervio Óptico/patología , Rubéola (Sarampión Alemán)/inmunología
7.
Clin Nephrol ; 64(5): 383-6, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16312267

RESUMEN

We present the case of a 75-year-old female with weight loss, anemia, systemic signs of inflammation, mild renal insufficiency, microscopic hematuria, mixed glomerular and tubular proteinuria, and high titers of PR3-ANCA. Renal biopsy demonstrated interstitial nephritis with some sclerosed but otherwise normal glomeruli. Extensive work-up showed no signs of granulomatous inflammation or other vasculitic organ involvement. We presumed this to be a rare renal manifestation of ANCA-associated disease with the presence of sclerosed glomeruli suggesting a previous history of glomerular involvement. In view of the absence of active vasculitic or granulomatous disease, treatment was limited to low-dose corticosteroids with good response.


Asunto(s)
Anticuerpos Anticitoplasma de Neutrófilos/sangre , Nefritis Intersticial/sangre , Serina Endopeptidasas/sangre , Anciano , Femenino , Humanos , Mieloblastina
8.
J Appl Microbiol ; 96(3): 630-40, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-14962144

RESUMEN

AIMS: The aims were to test whether Parvibaculum lavamentivoransT degraded commercial linear alkylbenzenesulphonate (LAS) surfactant via omega-oxygenation and beta-oxidation to sulphophenylcarboxylates (SPCs), whether the organism was widespread and reisolable, and whether the degradative community used the 4-sulphocatechol 1,2-dioxygenase to cleave the aromatic ring from LAS. METHODS AND RESULTS: Heterotrophic P. lavamentivoransT converted LAS (side chain length C10-C13) to SPCs (C4-C13), alpha,beta-unsaturated SPCs (C4-C13) and sulphophenyldicarboxylates (SPdCs) (at least C8-C12). Identifications came from high performance liquid chromatography (HPLC) separation, an electrospray interface and mass spectrometry. No evidence for other paths was found. The degradation of LAS in trickling filters inoculated with environmental samples always showed transient SPC intermediates (HPLC) and the presence of the P. lavamentivorans morphotype in the community. One new isolate was obtained. A community able to mineralize LAS contained 4-sulphocatechol-1,2-dioxygenase at high specific activity. CONCLUSIONS: Parvibaculum lavamentivoransT degrades commercial LAS via omega-oxygenation, oxidation and chain shortening through beta-oxidation to yield a wide range of SPCs. The latter are degraded in bacterial communities which contain organisms like P. lavamentivorans, and which utilize sulphocatechol dioxygenase for ring cleavage. SIGNIFICANCE AND IMPACT OF THE STUDY: There is one widespread pathway to degrade LAS. Any traces of LAS and larger amounts of SPCs in the effluent from sewage works are exposed to degradative organisms in acclimated and pristine environments. These degradative reactions can now be studied in pure cultures.


Asunto(s)
Ácidos Alcanesulfónicos/metabolismo , Tensoactivos/metabolismo , Contaminantes Químicos del Agua/metabolismo , Purificación del Agua/métodos , Técnicas Bacteriológicas , Biodegradación Ambiental , Oxidación-Reducción , Aguas del Alcantarillado
9.
J Mass Spectrom ; 36(6): 677-84, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11433542

RESUMEN

After liquid chromatographic (LC) separation, electrospray ionization mass spectrometry (ESI-MS) was investigated for the determination of the amphoteric surfactant cocamidopropylbetaine (CAPB). In the positive ion mode the molecule formed the adduct ions [M + H](+), [M + Na](+) and [M + K](+). Adducts of these cations were also detected with decreasing abundance as dimer and trimer clusters. Additionally, doubly charged molecular ions with different combinations of cations were identified. It was noticed that the relative abundances of individual cation adducts were not reproducible, apparently owing to varying contents of alkali metal ions originating from the solvent and the sample. Under negative ionization, the major molecular ion was [M - H](-). Higher clusters formed by two and three surfactant molecules, i.e. [2M - H](-) and [3M - H](-) were likewise registered. The tendency to form clusters in both positive and negative ion modes, even at 0.1 mg l(-1) levels, was attributed to strong electrostatic interactions between the zwitterionic head groups. Further evidence for this assumption was provided by the detection of a fragment formed from [2M - H](-) which contained the two charged head groups. Studies were undertaken in the negative ion mode on the concentration- and orifice voltage-dependent monomer, dimer and trimer formation of C(12)-CAPB in order to evaluate potential issues in using the ion [M - H](-) mode for quantitative analysis. Finally, the established (-)-LC/ESI-MS method was applied to follow up the primary degradation of CAPB in a laboratory-scale fixed-bed bioreactor (FBBR) spiked with a test concentration of 10 mg l(-1). Direct analysis without sample pretreatment revealed that higher alkyl homologues were more prone to adsorption. Primary biodegradation of all alkyl homologues was completed after a period of 4 days. Selected lyophilized FBBR samples were examined for the presence of transient or stable degradation intermediates, but no metabolite could be identified.

10.
Sci Total Environ ; 269(1-3): 75-85, 2001 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-11305345

RESUMEN

Laguna de Bay in the Philippines is one of the largest freshwater lakes in Asia and is considered a primary source of drinking water, but also receives daily discharges of effluent from both domestic and industrial activities. Branched alkylbenzenesulfonates (ABS), which were banned in Europe and withdrawn from the market in the U.S. since the mid-1960s, but not in Southeast Asia, and linear alkylbenzenesulfonates (LAS) are anionic surfactants used in detergent formulations and are therefore main components of effluent discharges. The presence of both LAS and ABS in several water streams in the catchment area of Laguna de Bay was determined using liquid chromatography-mass spectrometry (LC-MS). The concentration levels of LAS (1.2-73 and 2.2-102 microg l(-1)) and ABS (1.1-75 and 1-66 microg l(-1)) in some tributaries of Laguna de Bay and its outlet (Pasig River) to Manila Bay were assessed in December 1999 and March 2000, respectively. The LAS/ABS ratio was calculated as an indication of the extent of the distribution and fate of these surfactants in the surface water. The nearer the location to the metropolitan area of Manila, the higher the levels of LAS and ABS detected in the waters. Moreover, the extent of biodegradation was investigated by monitoring their alkyl homologue distribution and the presence of sulfophenylcarboxylate (SPC) metabolites. Similarly, differences in the levels of SPC and the homologues were apparent at the different sampling points. Presumably, even the quite recalcitrant ABS form SPCs under the conditions present in Southeast Asia. Since wastewater treatment facilities are not well established in developing countries like the Philippines, the call for the use of environmentally friendly chemicals is of even higher significance.


Asunto(s)
Ácidos Alcanesulfónicos/análisis , Monitoreo del Ambiente , Tensoactivos/análisis , Abastecimiento de Agua , Ácidos Alcanesulfónicos/metabolismo , Biodegradación Ambiental , Cromatografía Liquida , Humanos , Espectrometría de Masas , Filipinas , Salud Pública , Tensoactivos/metabolismo , Población Urbana
11.
J Chromatogr A ; 938(1-2): 67-77, 2001 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-11771848

RESUMEN

The aerobic biodegradability of an extensively used synthetic polymer was monitored the first time on a laboratory-scale fixed-bed bioreactor (FBBR) applying matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS). Polymeric poly(vinylpyrrolidone) (PVP) was spiked at concentrations of 10 mg l(-1) onto the FBBR run with river water and the biodegradation monitored after lyophilization of aliquots of the test liquor applying MALDI-TOF-MS. The latter proved to be a powerful tool for qualitative screening purposes of PVP in a molecular mass range <20 kDa in particularly yielding a high sensitivity and shot-to-shot reproducibility. The sample-to-sample reproducibility was enhanced applying the anchor target device. Post-source decay-MALDI-TOF-MS fragmentation investigations determined the unknown end groups of PVP unambiguously. Poor biodegradability of PVP can be assumed, since even after 30 days, no oxidation of the terminal groups and no difference in the repeating units was observed. A decrease in the molecular mass distribution can be drawn back rather to adsorption of PVP in the FBBR other than to biodegradation. This was further investigated performing an adsorption experiment with sewage sludge as solid matrix and analyses of the aqueous phase and sludge samples. Extrapolating these results to the situation in wastewater treatment plants, it is highly likely that PVP is eliminated from the dissolved phase by adsorption onto sludge particles.


Asunto(s)
Povidona/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Calibración , Cromatografía en Gel , Reproducibilidad de los Resultados
12.
J Chromatogr A ; 889(1-2): 195-209, 2000 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-10985551

RESUMEN

Seven laboratories participated in an inter-laboratory comparison exercise within the framework of the PRISTINE, SANDRINE and INEXsPORT European Union Projects. Solid-phase extraction (SPE) methodologies were used for the extraction of target analytes from wastewaters. The analytical strategies were based on liquid chromatography (LC) coupled to mass spectrometric (MS) or to fluorescent (FL) detection in all cases with the exception of one laboratory using a test-tube enzyme-linked immunosorbent assay kit. Samples were spiked with the surfactants nonylphenolpolyglycol ether, coconut diethanolamide, linear alkylbenzene sulfonate, nonylphenolpolyglycol ether sulfate, alkylpolyglycol ether and secondary alkane sulfonate. After enrichment on previously conditioned SPE cartridges, the SPE cartridges were distributed among the participating laboratories without the information about the amount of spiked surfactants. In addition, SPE cartridges loaded with a real-world environmental sample containing a tannery wastewater were also analyzed. The results of the programme showed that SPE followed by LC-MS techniques are reliable for the surfactants determination at submicrogram to microgram per liter levels in wastewaters. Inter-laboratory precision values were calculated as the reproducibility relative standard deviation (RSD(R)) which was determined from the reproducibility standard deviation (sR) and the average concentration at a particular concentration level. When data from all laboratories were pooled, the RSD(R) values ranged from 5.1 to 28.3% for the determination of target analytes. The most accurate result corresponded to that given for linear alkylbenzene sulfonates. Taking into account that different methodologies were used (including non-chromatographic techniques) and the complexity of the samples analyzed, it can be considered that acceptable reproducibility values were obtained in this inter-laboratory study.


Asunto(s)
Cromatografía Liquida/métodos , Ensayo de Inmunoadsorción Enzimática/métodos , Tensoactivos/análisis , Contaminantes Químicos del Agua/análisis , Espectrometría de Masas/métodos , Aguas del Alcantarillado/análisis , Agua/análisis
13.
J Chromatogr A ; 889(1-2): 221-9, 2000 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-10985553

RESUMEN

Linear alkylbenzenesulfonates (LASs) were determined in wastewaters and coastal waters by solid-phase extraction, using two different sample preparation protocols depending on the sample treated, followed by capillary electrophoresis and ultraviolet detection (CE-UV). The linear range of the proposed method varied from 3 to 53 and from 25 to 495 microg/l, depending on the compound, with a limit of detection of 1 microg/l when 250 ml of coastal water was preconcentrated. [M-H]- ions were used for CE-MS confirmation after quantification by CE-UV. CE-MS diagnostic ions were the same ones used in LC-electrospray (ESI) MS and corresponded to m/z 297, 311, 325 and 339 for C10, C11, C12 and C13 LASs, respectively. LASs were determined in wastewater samples of the influent and effluent of three wastewater treatment plants (WWTPs), two of them using biological treatment with secondary settlement and receiving mainly domestic wastewaters whereas one of the plants was operated with physicochemical treatment and received mainly industrial wastewaters. LASs were also analyzed in two samples from coastal waters of the bay of Cadiz (Spain) receiving untreated domestic effluents. All samples were also analyzed by LC-ESI-MS and the results are compared with the CE-UV method developed in this work. The concentration levels of total LASs varied from 988 to 1309 microg/l in the influents of WWTPs, whereas in the effluents the concentrations varied from 136 to 197 microg/l. The levels of LASs in coastal wastewaters of the bay of Cadiz varied from 739 to 911 microg/l, indicating that the wastewaters discharged into the bay did not undergo any treatment at all.


Asunto(s)
Ácidos Alcanesulfónicos/análisis , Electroforesis Capilar/métodos , Espectrometría de Masas/métodos , Agua de Mar/análisis , Automatización , Calibración , Espectrofotometría Ultravioleta/métodos , Contaminantes Químicos del Agua/análisis , Purificación del Agua , Abastecimiento de Agua
14.
Dermatol Clin ; 18(2): 359-77, xi-xii, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10791163

RESUMEN

Nontuberculous mycobacteria are playing an increasingly important role in human disease owing to higher prevalence of antibiotic resistance and immunodeficiency. These organisms cause a variety of cutaneous findings which are often misdiagnosed by the clinician. Compounding this problem is the fact that most mycobacteria require special culture conditions, which if not specifically requested, are frequently not used. Recognition of susceptible patients is imperative and is not limited to the immunocompromised. Successful treatment of mycobacterial infections requires knowledge of currently available and recommended antibiotics followed by tailoring of the antimicrobial regimen after sensitivity testing is performed.


Asunto(s)
Infecciones por Mycobacterium no Tuberculosas/patología , Micobacterias no Tuberculosas/clasificación , Enfermedades Cutáneas Bacterianas/patología , Humanos , Infecciones por Mycobacterium no Tuberculosas/microbiología , Micobacterias no Tuberculosas/patogenicidad , Enfermedades Cutáneas Bacterianas/microbiología
15.
J Mass Spectrom ; 35(3): 468-75, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10767779

RESUMEN

Alkyl glucamides (AGs) were analyzed by reversed-phase liquid chromatography (LC) coupled to mass spectrometry with electrospray ionization (ESMS). Analytes were separated according to the chain length of two homologs, C12- and C14-glucamide. Mass spectrometric detection in the positive ion mode exhibited higher overall sensitivity where, apart from fragments, different molecular and quasi-molecular ions were obtained. However, application of the negative ion mode offered advantages in terms of reproducibility and extent of information when analyzing environmental samples. Therefore, a simple and sensitive analytical methodology was developed for the determination of AGs in municipal sewage treatment plant influent and effluent based on solid-phase enrichment, LC separation and negative ion ESMS quantification. After preconcentration of 100 ml of aqueous sample, the recoveries using polymeric LiChrolut EN cartridges exceeded 89%. A quantification limit of 0.1 microg l(-1) was achieved. Studies on the biodegradability and metabolic pathway of C10-glucamide were carried out on a laboratory-scale microbial test unit under aerobic conditions. A postulated metabolism including omega-oxidation of the alkyl chain followed by subsequent beta-oxidations was checked by LC/ESMS. Identification and formation of 'C4-glucamide acid' as a degradation intermediate was confirmed by mass spectrometric studies. Higher homolog acids such as C10-, C8- and C6-glucamide acids, which should be predicted precursors of C4-glucamide acid, and any other metabolites, were not detectable, presumably owing to rapid breakdown.

17.
J Chromatogr A ; 854(1-2): 221-32, 1999 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-10497942

RESUMEN

Alkyl polyglucosides (APGs) were analyzed by reversed-phase liquid chromatography coupled to mass spectrometry with electrospray ionization. Analytes were separated according to the chain length of the alkyl homologues, whereas the separation of isomeric forms of the glucose moiety was achieved partially. Depending on the structure of the glucose ring the alkyl monoglucosides show a distinct affinity in terms of the formation of sodium and ammonium adduct ions. Metabolism of isomer pure alkyl monoglucosides was studied on a testfilter device to gather information about the degradation behavior and to obtain eventually poorly degradable metabolites. In spite of unsuccessful detection of any metabolites such as "polyglucoside alcanoic acids", a degradation pathway was proposed including the cleavage of the glucosidic bond as initial step. In addition, a method for the determination of APGs in municipal waste water effluent was developed using solid-phase extraction on reversed-phase material. Recovery rates were in the range of 66 to 98% for three spiked alkyl monoglucosides and a quantitation limit of 0.2 microg l(-1) was achieved.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Glucósidos/análisis , Residuos Industriales/análisis , Espectrometría de Masas/métodos , Contaminantes Químicos del Agua/análisis
20.
Anaesthesist ; 46(11): 969-73, 1997 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-9490585

RESUMEN

UNLABELLED: Wegener's granulomatosis is a distinct clinicopathologic entity characterized by granulomatous vasculitis of the upper and lower respiratory tract and glomerulonephritis. This disease can present as a clinical picture which resembles sepsis and adult respiratory distress syndrome (ARDS). Wegener's disease requires immunosuppression which can have detrimental consequences when used in sepsis. The following case report illustrates the diagnostic difficulties encountered by intensive care physicians treating severe pulmonary failure and multiple organ dysfunction in Wegener's granulomatosis appearing as ARDS with sepsis. CASE REPORT: A 19-year-old female patient had developed acute respiratory and renal failure after a prolonged period (many months) of antibiotic resistant otitis, sinusitis and mastoiditis. The patient had required intubation at another hospital and there was a history of tension pneumothorax and cardiopulmonary resuscitation during mechanical ventilation. Emergency extracorporeal membrane oxygenation (ECMO) for acute hypercapnic and hypoxic respiratory failure was instituted and the patient was transported to our institution while on ECMO. The patient was treated empirically for suspected pulmonary and systemic infection and received hydrocortisone (0.18 mg/kg/h) as part of a protocol-driven treatment of septic shock in addition to antibiotic and antimycotic regime. The use of ECMO was required for 10 and mechanical ventilation for another 50 days after admission. After successful extubation, central nervous system dysfunction became evident with a somnolent and generally unresponsive patient. When the hydrocortisone dose was gradually tapered, the clinical status of the patient further deteriorated, pulmonary gas exchange worsened and she developed renal failure with proteinura and hematuria. A renal biopsy was performed demonstrating vasculitis and focal segmental glomerulonephritis, a systemic granulomatous vasculitis was suspected; the serum was tested for anti-proteinase 3 antibodies (PR3-ANCA) and turned out to be positive (17.5 U/ml; normal range < 7 U/ml). The morphologic findings from renal biopsy, the positive test for antiproteinase 3 antibodies and the pulmonary-renal involvement with evidence of multisystem disease established the diagnosis of Wegener's granulomatosis. Immunosuppressive therapy with cyclophosphamide and prednisolone was instituted resulting in rapid improvement with recovery of pulmonary, renal and central nervous system function within two weeks. The use of ECMO in this patient served as a life-saving immediate measure usefull to "buy time" until a definite diagnosis could be established. ARDS represents an uniform pulmonary reaction to a large number of different noxious stimuli and disease entities. This case demonstrates that intensive care physicians caring for critically ill patients with ARDS should include even rare causes of pulmonary injury into their differential diagnosis.


Asunto(s)
Granulomatosis con Poliangitis/complicaciones , Inmunosupresores/efectos adversos , Síndrome de Dificultad Respiratoria/complicaciones , Lesión Renal Aguda/etiología , Lesión Renal Aguda/fisiopatología , Adulto , Oxigenación por Membrana Extracorpórea , Femenino , Granulomatosis con Poliangitis/diagnóstico por imagen , Granulomatosis con Poliangitis/tratamiento farmacológico , Humanos , Inmunosupresores/uso terapéutico , Riñón/patología , Insuficiencia Multiorgánica/etiología , Insuficiencia Multiorgánica/fisiopatología , Síndrome de Dificultad Respiratoria/diagnóstico por imagen , Tomografía Computarizada por Rayos X
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