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1.
Parasitol Res ; 120(10): 3603-3610, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34432154

RESUMO

Alveolar echinococcosis is the most severe worm disease primarily detected in the liver. This study aimed to determine the clinical tolerance and efficacy of albendazole in patients with alveolar echinococcosis, depending on the volume of previous surgical treatment or its absence and the duration of anti-parasitic therapy. We retrospectively (over the last 15 years) analyzed the data of 117 patients, who were divided into 4 groups according to curability: R0 (radical resection), R1+2 (incomplete resection), Nr (unresectable), and Rr (recurrence). All of them received albendazole from 3 months to 11 years, depending on the volume of resection. We evaluated patients' tolerability of albendazole according to the level of hepatic transaminases and blood cell count. The effectiveness of anti-parasitic treatment was evaluated by imaging studies and the absence of serum antibodies. There was no direct relationship between the frequency of adverse reactions and the duration of taking albendazole (r - 0.20229). Adverse reactions were significantly more often observed in unresectable patients (p < 0.01), which is most likely associated with the general serious condition of the patients and with individual drug intolerance. The effectiveness of the anti-parasitic treatment was manifested in the inhibition of tumor development in 88% of patients in group R1+2 and 60% in group Nr. Follow-up of group R0 patients from 3 to 14 years did not reveal new lesions of the liver and other organs. The chance of a complete cure depends on the early detection of a parasitic tumor and can reach 50%.


Assuntos
Albendazol , Equinococose Hepática , Albendazol/efeitos adversos , Equinococose , Equinococose Hepática/tratamento farmacológico , Seguimentos , Humanos , Estudos Retrospectivos
2.
Transpl Infect Dis ; 22(4): e13291, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32277859

RESUMO

BACKGROUND: This study focused on the monitoring of patients who had undergone liver transplantation (LT) because of unresectable alveolar echinococcosis (AE). The role of long-term administration of albendazole (ABZ) in patients with residual/recurrent AE lesions and without AE lesions was evaluated. METHODS: Albendazole therapy was prescribed to patients diagnosed with AE 4-6 weeks after LT on the background of continuous suppressive therapy while following the protocol for managing patients after LT. Clinical data (general condition, blood counts, and level of hepatic transaminases), ultrasound scans (USs), magnetic resonance imaging (MRI) or multispiral computed tomography (MSCT), and serological data were collected from four patients with residual/recurrent AE lesions and without AE lesions. The results of the USs, MRI, and MSCT examinations at diagnosis and at the end of follow-up were retrospectively reviewed for all patients. RESULTS: Observation of patients over a long period (up to 10 years) showed that the continuous (without interruption) use of ABZ restrained the development of metacestodes. Interruptions in taking the drug, associated with the manifestation of hepatotoxicity in some patients, led to the development of lesions in other organs in which the parasite had not previously been detected. No new foci were found in the transplanted livers of the patients. CONCLUSION: Liver transplantation, together with continuous anti-relapse chemotherapy, prolongs the patient's life, both in the absence and in the presence of metastases in other organs.


Assuntos
Albendazol/uso terapêutico , Antiprotozoários/uso terapêutico , Esquema de Medicação , Equinococose/tratamento farmacológico , Transplante de Fígado , Adulto , Animais , Equinococose/complicações , Equinococose/diagnóstico , Echinococcus multilocularis/efeitos dos fármacos , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/efeitos dos fármacos , Fígado/parasitologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Fatores de Tempo , Tomografia Computadorizada por Raios X
3.
Dalton Trans ; 46(9): 2785-2792, 2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-28174762

RESUMO

Gadolinium dioxycarbonates co-doped with different visible emitting lanthanides were synthesized via a co-precipitation method using oxalic acid as a precipitating agent. Through XRD and DTA/TG investigations, the type-II hexagonal phase of the lanthanide dioxycarbonates was confirmed for all of the samples. The materials constitute of big agglomerates formed by submicrometrical particles. By varying the Ln3+ doping percentages and ratios and by changing the excitation wavelength the gadolinium dioxycarbonates activated with Sm3+, Eu3+, Tb3+, Dy3+ and Tm3+ showed tunable emission colors. Luminescence measurements were performed in order to determine: the luminescence behavior of the ions, the CIE coordinates, the CCT values and potential energy transfer. Interesting results were achieved upon exciting the samples at 351 nm and 365 nm demonstrating the possibility to obtain white emission in the dioxycarbonate matrix.

4.
J Mass Spectrom ; 41(10): 1315-21, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16981211

RESUMO

The mechanism of atmospheric pressure (AP) laser ionization of water and water/glycerol liquid samples at a 3-microm wavelength is studied experimentally. For the ion desorption, an in-house built Yb : YAG-pumped optical parametric oscillator (OPO) infrared (IR) laser has been coupled with AP MALDI ion source interfaced to an ion trap mass spectrometer (MS). It has been shown that water is primarily responsible for ion generation in water/glycerol samples, while glycerol increases the solution viscosity and decreases the water evaporation rate and sample losses. In contrast to AP UV-MALDI, the electric field in the case of AP IR-MALDI does not assist in ion production. It was found that the absence of the electrical field provides the optimum ionization condition both for water and water/glycerol liquid samples at the 3-microm laser irradiation. A two-stage ion formation mechanism, which includes the initial emission of microdroplets and release of molecular ions at the second stage, can explain the experimentally observed ion signal dependencies upon the voltage applied between MS inlet and the MALDI sample plate. Postionization using additional corona discharge APCI increases the observed signal by approximately 50%, which indicates that some portion of the analyte is desorbed in the form of neutral molecules.


Assuntos
Soluções/química , Soluções/efeitos da radiação , Pressão do Ar , Angiotensina II/química , Glicerol/química , Raios Infravermelhos , Íons/química , Íons/efeitos da radiação , Lasers , Peptídeos/química , Água/química
5.
J Mass Spectrom ; 39(8): 913-21, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15329843

RESUMO

An atmospheric pressure (AP) infrared (IR) laser ionization technique, implemented on a quadrupole ion trap mass spectrometer, was used to analyze underivatized, N-linked oligosaccharides in solution. Experiments were conducted on an atmospheric pressure infrared ionization from solution (AP-IRIS) ion source which differed from previous AP IR matrix-assisted laser desorption/ionization (MALDI) interfaces in that the ion source operated in the absence of an extraction electric field with a higher power 2.94 microm IR laser. The general term 'IRIS' is used as the mechanism of ionization differs from that of MALDI, and is yet to be fully elucidated. The AP-IRIS ion source demonstrated femtomole-level sensitivity for branched oligosaccharides. AP-IRIS showed approximately 16 times improved sensitivity for oligomannose-6 and the core-fucosylated glycan M3N2F over optimal results obtainable on a AP UV-MALDI with a 2,4,6-trihydroxyacetophenone matrix. Comparison between IR and UV cases also showed less fragmentation in the IR spectrum for a glycan with a conserved trimannosyl core, core-substituted with fucose. A mixture of complex, high-mannose and sialylated glycans resulted in positive ion mass spectra with molecular ion peaks for each sugar. Tandem mass spectrometry of the sodiated molecular ions in a mixture of glycans revealed primarily glycosidic (B, Y) cleavages. The reported results show the practical utility of AP-IRIS while the ionization mechanism is still under investigation.


Assuntos
Oligossacarídeos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Pressão do Ar , Raios Infravermelhos , Lasers , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
6.
Anal Chem ; 75(7): 1628-37, 2003 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12705595

RESUMO

A novel approach to microbial detection using atmospheric pressure matrix-assisted laser desorption/ionization with an ion trap mass spectrometer to analyze whole cell bacteria is introduced. This new approach was tested with lyophilized spores and cultures of Bacillus globigii (BG) grown on agar media for 4 days or longer. At each stage of growth, it was found that biomarkers, identified as cyclic lipopeptides known as fengycin and surfactin, could be detected by pulsed ultraviolet laser irradiation of intact BG cells (approximately 5 mg) cocrystallized with alpha-cyano-4-hydroxycinnamic acid. Furthermore, definitive amino acid sequence information was obtained by performing tandem mass spectrometry on the precursor ions of the cyclic lipopeptides. The investigation was broadened to include the examination of aerosolized BG spores collected from the atmosphere and directly deposited onto double-sided tape. Subsequent analysis of the recovered spores resulted in the production of mass peaks consistent with fengycin. Other Bacillus species were analyzed for comparison and showed mass spectral peaks also identified as originating from various cyclic lipopeptides. Further studies were conducted using a pulsed infrared laser as the excitation source to analyze BG cells (approximately 5 mg) suspended in a matrix of 0.03 M ammonium citrate and glycerol resulting in the production of ions characteristic of fengycin and surfactin.


Assuntos
Bacillus/química , Proteínas de Bactérias/análise , Lipoproteínas/análise , Peptídeos Cíclicos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Aerossóis , Sequência de Aminoácidos , Pressão Atmosférica , Proteínas de Bactérias/química , Biomarcadores/análise , Biomarcadores/química , Ciclização , Lipopeptídeos , Lipoproteínas/química , Especificidade da Espécie
7.
Rapid Commun Mass Spectrom ; 16(18): 1737-42, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12207361

RESUMO

A recently developed commercial atmospheric pressure matrix-assisted laser desorption/ionization (AP-MALDI) source (MassTech, Inc.) was modified to adopt commercially available DIOS plates (Mass Consortium Corp.) for the studies of laser desorption from the surface of porous silicon under atmospheric pressure conditions. The feasibility of atmospheric pressure laser desorption/ionization from the surface of porous silicon (AP-DIOS) was demonstrated. The advantages of this new AP-DIOS technique include reasonably good sensitivity (subpicomole range for standard peptide mixtures), simplicity of sample preparation, uniformity of target spots and the absence of matrix peaks in the spectra. The AP-DIOS source was interfaced with a commercial ion trap (LCQ Classic, Thermo Finnigan) which additionally provides a unique MS(n) capability. The AP-DIOS spectrum of 250 fmol of unseparated tryptic digest of bovine serum albumin (BSA) was compared with that of AP-MALDI for the same compound. AP-DIOS offers significantly better coverage for the digest components in the mass range 200-1000 Da. The combined data of both techniques enabled us to nearly double the number of matched peaks in BSA digest analysis compared with AP-DIOS or AP-MALDI analysis separately.


Assuntos
Silício/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/instrumentação , Angiotensinas/química , Pressão Atmosférica , Microcomputadores , Fragmentos de Peptídeos/química , Porosidade , Soroalbumina Bovina/química , Verapamil/química
8.
J Am Soc Mass Spectrom ; 13(4): 354-61, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11951973

RESUMO

A new atmospheric pressure (AP) infrared (IR) matrix-assisted laser desorption/ionization (MALDI) ion source was developed and interfaced with a Thermo Finnigan LCQ ion trap mass spectrometer. The source utilized a miniature all-solid-state optical parametric oscillator (OPO)-based IR laser system tunable in the lambda = 1.5-4 microm spectral range and a nitrogen ultraviolet (UV) laser (lambda = 337 nm) for use in comparative studies. The system demonstrated comparable performance at 3 microm and 337 nm wavelengths if UV matrices were used. However, AP IR-MALDI using a 3 microm wavelength showed good performance with a much broader choice of matrices including glycerol and liquid water. AP IR-MALDI mass spectra of peptides in the mass range up to 2000 Da were obtained directly from aqueous solutions at atmospheric conditions for the first time. A potential use of the new AP IR-MALDI ion source includes direct MS analysis of biological cells and tissues in a normal atmospheric environment as well as on-line coupling of mass spectrometers with liquid separation techniques.


Assuntos
Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Pressão do Ar , Raios Infravermelhos , Lasers , Peptídeos/química , Soluções/química , Água/química
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