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1.
J Neuroinflammation ; 14(1): 123, 2017 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-28645295

RESUMO

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.


Assuntos
Autoanticorpos/metabolismo , Microdomínios da Membrana/metabolismo , Proteínas de Membrana/metabolismo , Esclerose Múltipla/metabolismo , Adulto , Animais , Autoanticorpos/imunologia , Feminino , Células HEK293 , Humanos , Masculino , Microdomínios da Membrana/imunologia , Proteínas de Membrana/imunologia , Pessoa de Meia-Idade , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Ratos , Suínos
2.
J Neurol Neurosurg Psychiatry ; 79(10): 1134-6, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18270237

RESUMO

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.


Assuntos
Anticorpos Antivirais/imunologia , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/imunologia , Neuromielite Óptica/diagnóstico , Neuromielite Óptica/imunologia , Adulto , Idoso , Varicela/imunologia , Diagnóstico Diferencial , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imageamento por Ressonância Magnética , Masculino , Sarampo/imunologia , Pessoa de Meia-Idade , Nervo Óptico/imunologia , Nervo Óptico/patologia , Rubéola (Sarampo Alemão)/imunologia
3.
J Neurol ; 264(3): 453-466, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28005176

RESUMO

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.


Assuntos
Anticorpos Antivirais/líquido cefalorraquidiano , Herpesvirus Humano 3/imunologia , Vírus do Sarampo/imunologia , Esclerose Múltipla/líquido cefalorraquidiano , Vírus da Rubéola/imunologia , Biomarcadores/líquido cefalorraquidiano , Humanos , Esclerose Múltipla/virologia
4.
J Am Coll Cardiol ; 20(5): 1175-9, 1992 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-1401619

RESUMO

OBJECTIVES AND BACKGROUND: Severe primary tricuspid regurgitation in the adult is a rare finding. This study describes the diagnostic findings and the treatment of an isolated congenital cleft of the anterior leaflet of the tricuspid valve as the morphologic substrate for severe tricuspid regurgitation. METHODS: The clinical, echocardiographic findings and the follow-up findings of five patients (all male, 20 to 56 years old) with this disorder are described. Four of the five patients underwent cardiac surgery that confirmed the diagnosis. RESULTS: In three of five patients, exertional fatigue was the limiting symptom (New York Heart Association functional classes II and III). The clinical findings included a holosystolic murmur and supraventricular arrhythmias in all patients. Cardiac catheterization, performed in four patients, yielded the incorrect diagnosis of Ebstein's anomaly in three. In one patient the cleft was associated with an atrial septal defect of the secundum type. In four of five patients successful reconstruction of the tricuspid valve with a DeVega annuloplasty was performed. One patient had a partial excision of the right atrium, and one had a closure of a coexisting atrial septal defect. One patient refused operation. CONCLUSIONS: Tricuspid valve anomalies can be accurately identified by Doppler echocardiography. Surgical repair is the treatment of choice in patients with severe tricuspid regurgitation due to a congenital cleft of the anterior leaflet of the tricuspid valve.


Assuntos
Insuficiência da Valva Tricúspide/etiologia , Valva Tricúspide/anormalidades , Adulto , Cateterismo Cardíaco , Ecocardiografia/métodos , Ecocardiografia Doppler/métodos , Eletrocardiografia , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/classificação , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Insuficiência da Valva Tricúspide/cirurgia
5.
Clin Nephrol ; 64(5): 383-6, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16312267

RESUMO

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.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos/sangue , Nefrite Intersticial/sangue , Serina Endopeptidases/sangue , Idoso , Feminino , Humanos , Mieloblastina
6.
Peptides ; 16(4): 665-71, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7479301

RESUMO

Effects of alpha-melanocyte-stimulating hormone (alpha-MSH), beta-melanocyte-stimulating hormone (beta-MSH), beta-lipotropin (beta-LPH), and beta-endorphin (beta-EPH) at concentrations from 10(-9) M up to 10(-6) M on human adipose tissue lipoprotein lipase (LPL) were studied in a cell-free system. alpha-MSH and beta-MSH did not exert any effect on LPL; no degradation of these peptides in the incubation medium could be detected by HPLC analysis. beta-LPH and beta-EPH failed to alter enzyme activity. However, HPLC analysis revealed an unspecific rapid degradation of the peptides due to the activity of tissue proteases. Therefore, the protease inhibitors amastatin, antipain, APMSF, and TPCK were tested at concentrations of 10(-5), 10(-4), and 10(-3) M for their efficacy to inhibit degradation. None of the inhibitors was able to substantially reduce proteolysis of beta-LPH, as was the case with amastatin, APMSF, and TPCK for beta-EPH. However, antipain at 10(-4) M preserved at least 20% of the initial peptide concentration from proteolysis up to 150 min. Antipain caused a decrease in lipoprotein lipase activity (LPLA), which was dependent on concentration. The adverse effect of antipain at concentrations of 10(-4) M on LPL was completely abolished by beta-EPH at a concentration of 10(-6) M.


Assuntos
Lipase Lipoproteica/metabolismo , Pró-Opiomelanocortina/farmacologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Sistema Livre de Células , Ácidos Graxos não Esterificados/metabolismo , Humanos , Lipoproteínas VLDL/biossíntese , Lipoproteínas VLDL/metabolismo , Fígado/efeitos dos fármacos , Fígado/fisiologia , Hormônios Estimuladores de Melanócitos/farmacologia , Inibidores de Proteases/farmacologia , Triglicerídeos/sangue , alfa-MSH/farmacologia , beta-Endorfina/farmacologia , beta-Lipotropina/farmacologia
7.
J Mass Spectrom ; 36(6): 677-84, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11433542

RESUMO

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.

8.
J Chromatogr A ; 854(1-2): 221-32, 1999 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-10497942

RESUMO

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.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Glucosídeos/análise , Resíduos Industriais/análise , Espectrometria de Massas/métodos , Poluentes Químicos da Água/análise
9.
J Chromatogr A ; 938(1-2): 67-77, 2001 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-11771848

RESUMO

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.


Assuntos
Povidona/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Calibragem , Cromatografia em Gel , Reprodutibilidade dos Testes
10.
J Chromatogr A ; 889(1-2): 221-9, 2000 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-10985553

RESUMO

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.


Assuntos
Ácidos Alcanossulfônicos/análise , Eletroforese Capilar/métodos , Espectrometria de Massas/métodos , Água do Mar/análise , Automação , Calibragem , Espectrofotometria Ultravioleta/métodos , Poluentes Químicos da Água/análise , Purificação da Água , Abastecimento de Água
11.
J Chromatogr A ; 889(1-2): 195-209, 2000 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-10985551

RESUMO

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.


Assuntos
Cromatografia Líquida/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Tensoativos/análise , Poluentes Químicos da Água/análise , Espectrometria de Massas/métodos , Esgotos/análise , Água/análise
12.
Dermatol Clin ; 18(2): 359-77, xi-xii, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10791163

RESUMO

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.


Assuntos
Infecções por Mycobacterium não Tuberculosas/patologia , Micobactérias não Tuberculosas/classificação , Dermatopatias Bacterianas/patologia , Humanos , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas/patogenicidade , Dermatopatias Bacterianas/microbiologia
13.
Sci Total Environ ; 269(1-3): 75-85, 2001 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-11305345

RESUMO

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.


Assuntos
Ácidos Alcanossulfônicos/análise , Monitoramento Ambiental , Tensoativos/análise , Abastecimento de Água , Ácidos Alcanossulfônicos/metabolismo , Biodegradação Ambiental , Cromatografia Líquida , Humanos , Espectrometria de Massas , Filipinas , Saúde Pública , Tensoativos/metabolismo , População Urbana
15.
Praxis (Bern 1994) ; 100(6): 367-71, 2011 Mar 16.
Artigo em Alemão | MEDLINE | ID: mdl-21412749

RESUMO

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.


Assuntos
Transtornos da Cefaleia/etiologia , Herpes Simples/diagnóstico , Herpesvirus Humano 2 , Meningite Asséptica/diagnóstico , Meningite Viral/tratamento farmacológico , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Oncogene ; 30(22): 2547-57, 2011 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-21278786

RESUMO

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.


Assuntos
Neoplasias da Mama/tratamento farmacológico , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/uso terapêutico , Receptor ErbB-2/metabolismo , Neoplasias da Mama/enzimologia , Linhagem Celular Tumoral , Feminino , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor ErbB-3/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores
17.
Schweiz Med Wochenschr ; 120(45): 1697-700, 1990 Nov 10.
Artigo em Alemão | MEDLINE | ID: mdl-2251488

RESUMO

In 12,576 consecutive Doppler-echocardiographic studies (DE) performed on 11,450 patients over 3 years (1987-1989), 183 newly diagnosed congenital heart abnormalities were detected in 161 patients. The age of the 161 patients (86 female, 75 male) ranged from 16 to 84 years (median 34.5). The highest incidences of pathologies were those of ASD II (29%) and VSD (11%). With decreasing frequency the following abnormalities were diagnosed: pulmonary valve disease (8%), interatrial septal aneurysms (7%), membranous subvalvular aortic stenosis (5%), anomalous pulmonary venous connections (4%), atrioventricular canal defects (4%), persistent left superior venae cavae (4%), patent ductus arteriosus (4%), aneurysms of the membranous septum (4%), and sinus venosus defects (3%). Less common findings were coarctation of the aorta (2.5%), persistent sinusoids (2.5%), arteriovenous fistulas (2.5%), congenital LV-aneurysms (2.5%), Ebstein's anomalies (1%), anomalies of the papillary muscles (1%) and RV-dysplasias (1%). Rare findings were a cor triatriatum, a tetralogy of Fallot, a partial defect of the pericardium, a pulmonic atresia with VSD, an isolated cleft of the tricuspid valve, and finally a connection of a hepatic vein to the right atrium. In conclusion, we found an incidence of 1.4% in newly diagnosed congenital heart disease in adolescents and adults undergoing DE. 32 of 159 patients (20%) were referred to surgery, while endocarditis prophylaxis was indicated in 45%.


Assuntos
Ecocardiografia , Cardiopatias Congênitas/diagnóstico por imagem , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Defeitos dos Septos Cardíacos/diagnóstico por imagem , Doenças das Valvas Cardíacas/congênito , Doenças das Valvas Cardíacas/diagnóstico por imagem , Ventrículos do Coração/anormalidades , Humanos , Masculino , Pessoa de Meia-Idade
18.
Schweiz Med Wochenschr ; 118(39): 1398-402, 1988 Oct 01.
Artigo em Alemão | MEDLINE | ID: mdl-3175578

RESUMO

To control the quality of our care and to define the potential for lifesaving early intervention in patients with acute myocardial infarction, we analyzed the course of 709 patients (66.4 +/- 10.8 yrs) admitted to the coronary care unit for acute myocardial infarction over a period of 36 months. 77 patients (70.2 +/- 9.3 yrs) died in the coronary care unit, and thus early mortality was 10.9%. Only 8% died from disturbances of cardiac rhythm and 19% from rupture of a ventricle. 73% died in cardiogenic shock, of whom 21 were below 70 years old and represent a potential group for early intervention. In 13 patients of this subgroup possibilities of better management in the pre-hospital phase were found retrospectively. In 5/77 patients the optimal treatment was not achieved during clinical course. Cardiogenic shock is the major cause of death in the early phase of acute myocardial infarction. A further substantial reduction of mortality will be achieved only by reaching more risk patients in the pre-infarction phase and by shortening the pre-hospital phase.


Assuntos
Cuidados Críticos/normas , Infarto do Miocárdio/mortalidade , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Arritmias Cardíacas/mortalidade , Custos e Análise de Custo , Cuidados Críticos/economia , Feminino , Ruptura Cardíaca/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/terapia , Garantia da Qualidade dos Cuidados de Saúde , Estudos Retrospectivos , Choque Cardiogênico/mortalidade
19.
Schweiz Med Wochenschr ; 111(45): 1725-7, 1981 Nov 07.
Artigo em Alemão | MEDLINE | ID: mdl-7313643

RESUMO

Hemodynamic parameters have recently been described which are of prognostic importance for the outcome of valve replacement in patients with aortic insufficiency. It was investigated whether pathological values for the left ventricular end-systolic volume index, the ejection fraction, the end-diastolic radius/wall thickness ratio, the end-systolic diameter (DS) and shortening of the diameter (Sh), and the end-diastolic volume index are accompanied by morphological alterations evaluated from left ventricular endomyocardial biopsies. Hypertrophy of the cardiac fibers was significantly increased in patients in whom preoperative Sh was less than 25% and DS greater than 55 mm. In contrast, left ventricular interstitial fibrosis did not differ between these patients and those with Sh greater than or equal to 25% and DS less than or equal to 55 mm.


Assuntos
Insuficiência da Valva Aórtica/patologia , Ventrículos do Coração/patologia , Hemodinâmica , Adolescente , Adulto , Idoso , Valva Aórtica/patologia , Insuficiência da Valva Aórtica/cirurgia , Biópsia , Próteses Valvulares Cardíacas , Humanos , Pessoa de Meia-Idade , Prognóstico
20.
J Mass Spectrom ; 35(3): 468-75, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10767779

RESUMO

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.

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