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1.
Rev Sci Instrum ; 94(2): 023201, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36859035

RESUMEN

We have added a multipole ion trap to the existing photon-ion spectrometer at PETRA III (PIPE). Its hybrid structure combines a ring-electrode trap with a segmented 16-pole trap. The interaction of gases and ions with extreme ultraviolet radiation from the beamline P04 is planned to be investigated with the newly installed multipole trap. The research focus lies on radiation-induced chemical reactions that take place in the interstellar medium or in the atmospheres of planets, including natural as well as man-made processes that are important in the Earth's atmosphere. In order to determine the mass-to-charge ratio of the stored ions as efficiently as possible, we are using an ion time-of-flight spectrometer. With this technique, all stored ions can be detected simultaneously. To demonstrate the possibilities of the trap setup, two experiments have been carried out: The photoionization of xenon and the ion-impact ionization of norbornadiene. This type of ion-impact ionization can, in principle, also take place in planetary atmospheres. In addition to ionization by photon or ion impact, chemical reactions of the trapped ions with neutral atoms or molecules in the gas phase have been observed. The operation of the trap enables us to simulate conditions similar to those in the ionosphere.

2.
Chemphyschem ; 24(11): e202300061, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36815408

RESUMEN

Carbon 1s core-hole excitation of the molecular anion C2 - has been experimentally studied at high resolution by employing the photon-ion merged-beams technique at a synchrotron light source. The experimental cross section for photo-double-detachment shows a pronounced vibrational structure associated with 1 σ u → 3 σ g ${1\sigma _u \to 3\sigma _g }$ and 1 σ g → 1 π u ${1\sigma _g \to 1\pi _u }$ core excitations of the C2 - ground level and first excited level, respectively. A detailed Franck-Condon analysis reveals a strong contraction of the C2 - molecular anion by 0.2 Šupon this core photoexcitation. The associated change of the molecule's moment of inertia leads to a noticeable rotational broadening of the observed vibrational spectral features. This broadening is accounted for in the present analysis which provides the spectroscopic parameters of the C2 - 1 σ u - 1 3 σ g 2 2 Σ u + ${1\sigma _u^{ - 1} \,3\sigma _g^2 \;^2 \Sigma _u^ + }$ and 1 σ g - 1 3 σ g 2 2 Σ g + ${1\sigma _g^{ - 1} \,3\sigma _g^2 \;^2 \Sigma _g^ + }$ core-excited levels.

3.
J Phys Chem Lett ; 12(5): 1390-1395, 2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33508188

RESUMEN

The F 1s core level photoionization of the ionic molecular radical HF+ has been studied using the photon-ion merged-beams technique at a synchrotron radiation source. Upon analyzing kinetic energy release (KER) dependent photoion yield spectra, complex ultrafast dissociation dynamics of the F 1s core hole excited σ* state can be revealed. By means of configuration-interaction electronic structure calculations of the excited molecular potential energy curves, this complex process can be attributed to a spin-dependent dissociation of the excited σ* biradical state.

4.
Phys Rev Lett ; 124(8): 083203, 2020 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-32167340

RESUMEN

We report on new measurements of m-fold photodetachment (m=2-5) of carbon anions via K-shell excitation and ionization. The experiments were carried out employing the photon-ion merged-beams technique at a synchrotron light source. While previous measurements were restricted to double detachment (m=2) and to just the lowest-energy K-shell resonance at about 282 eV, our absolute experimental m-fold detachment cross sections at photon energies of up to 1000 eV exhibit a wealth of new thresholds and resonances. We tentatively identify these features with the aid of detailed atomic-structure calculations. In particular, we find unambiguous evidence for fivefold detachment via double K-hole production.

5.
J Appl Microbiol ; 128(1): 124-137, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31573710

RESUMEN

AIMS: To add a spore germination step in order to reduce decontamination temperature and time requirements compared to the current hot, humid air decontamination parameters, which are 75-80°C, ≥72 h, 70-90% RH, down to ≤60°C and ≤24 h total decontamination time. METHODS AND RESULTS: Bacillus anthracis spore germination with l-alanine+inosine+calcium dipicolinate (CaDPA) was quantified at 0-40°C, several time points and spore concentrations of 5-9 log10 per ml. Germination efficiency at 0-40°C was >99% at <8 log10 spores per ml. The temperature optimum was 20°C. Germination efficiency was significantly higher but slower at 0°C compared to ≥30°C at ≥8 log10 spores per ml. A single germinant application followed by 60°C, 1-h treatment consistently inactivated >2 log10 (>99%) of spores. However, a repeat application of germinant was needed to achieve the objective of ≥6 log10 spore inactivation out of a 7 log10 challenge (≥99·9999%) for ≤24 h total decontamination time for nylon and aircraft performance coating. CONCLUSIONS: l-alanine+inosine+CaDPA stimulated germination across wide temperature and spore concentration ranges. SIGNIFICANCE AND IMPACT OF THE STUDY: Germination expands the scope of spore decontamination to include materials from any industry sector that can be sprayed with an aqueous germinant solution.


Asunto(s)
Bacillus anthracis/fisiología , Descontaminación/métodos , Esporas Bacterianas/fisiología , Alanina/farmacología , Bacillus anthracis/efectos de los fármacos , Bacillus anthracis/crecimiento & desarrollo , Calor , Inosina/farmacología , Ácidos Picolínicos/farmacología , Esporas Bacterianas/efectos de los fármacos , Esporas Bacterianas/crecimiento & desarrollo , Factores de Tiempo
6.
Phys Rev Lett ; 120(13): 133202, 2018 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-29694177

RESUMEN

Double and triple detachment of the F^{-}(1s^{2}2s^{2}2p^{6}) negative ion by a single photon have been investigated in the photon energy range 660 to 1000 eV. The experimental data provide unambiguous evidence for the dominant role of direct photodouble detachment with a subsequent single-Auger process in the reaction channel leading to F^{2+} product ions. Absolute cross sections were determined for the direct removal of a (1s+2p) pair of electrons from F^{-} by the absorption of a single photon.

7.
J Appl Microbiol ; 120(4): 1074-84, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26786717

RESUMEN

AIM: To develop test methods and evaluate survival of Bacillus thuringiensis kurstaki cry(-) HD-1 and B. thuringiensis Al Hakam spores after exposure to hot, humid air inside of a C-130 aircraft. METHODS AND RESULTS: Bacillus thuringiensis spores were either pre-inoculated on 1 × 2 or 2 × 2 cm substrates or aerosolized inside the cargo hold of a C-130 and allowed to dry. Dirty, complex surfaces (10 × 10 cm) swabbed after spore dispersal showed a deposition of 8-10 log10 m(-2) through the entire cargo hold. After hot, humid air decontamination at 75-80°C, 70-90% relative humidity for 7 days, 87 of 98 test swabs covering 0·98 m(2) , showed complete spore inactivation. There was a total of 1·67 log10 live CFU detected in 11 of the test swabs. Spore inactivation in the 98 test swabs was measured at 7·06 log10 m(-2) . CONCLUSIONS: Laboratory test methods for hot, humid air decontamination were scaled for a large-scale aircraft field test. The C-130 field test demonstrated that hot, humid air can be successfully used to decontaminate an aircraft. SIGNIFICANCE AND IMPACT OF THE STUDY: Transition of a new technology from research and development to acquisition at a Technology Readiness Level 7 is unprecedented.


Asunto(s)
Aeronaves , Bacillus anthracis/aislamiento & purificación , Bacillus thuringiensis/aislamiento & purificación , Descontaminación/métodos , Calor , Humedad , Bacillus anthracis/fisiología , Bacillus thuringiensis/fisiología , Epidemias/prevención & control , Esporas Bacterianas/crecimiento & desarrollo
8.
J Appl Microbiol ; 119(5): 1263-77, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26258399

RESUMEN

AIMS: To develop test methods and evaluate survival of Bacillus anthracis ∆Sterne or Bacillus thuringiensis Al Hakam on materials contaminated with dirty spore preparations after exposure to hot, humid air using response surface modelling. METHODS AND RESULTS: Spores (>7 log10 ) were mixed with humic acid + spent sporulation medium (organic debris) or kaolin (dirt debris). Spore samples were then dried on five different test materials (wiring insulation, aircraft performance coating, anti-skid, polypropylene, and nylon). Inoculated materials were tested with 19 test combinations of temperature (55, 65, 75°C), relative humidity (70, 80, 90%) and time (1, 2, 3 days). The slowest spore inactivation kinetics was on nylon webbing and/or after addition of organic debris. CONCLUSIONS: Hot, humid air effectively decontaminates materials contaminated with dirty Bacillus spore preparations; debris and material interactions create complex decontamination kinetic patterns; and B. thuringiensis Al Hakam is a realistic surrogate for B. anthracis. SIGNIFICANCE AND IMPACT OF THE STUDY: Response surface models of hot, humid air decontamination were developed which may be used to select decontamination parameters for contamination scenarios including aircraft.


Asunto(s)
Bacillus anthracis/crecimiento & desarrollo , Bacillus thuringiensis/crecimiento & desarrollo , Descontaminación/métodos , Esporas Bacterianas/crecimiento & desarrollo , Calor , Cinética
9.
Phys Rev Lett ; 114(1): 013002, 2015 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-25615465

RESUMEN

Single, double, and triple ionization of C(1+) ions by single photons is investigated in the energy range of 286-326 eV, i.e., in the range from the lowest-energy K-vacancy resonances to well beyond the K-shell ionization threshold. Clear signatures of C(1+)(1s2s(2)2p(2) (2)D,(2)P) resonances are found in the triple-ionization channel. The only possible mechanism producing C(4+)(1s(2)) via these resonances is direct triple-Auger decay, i.e., a four-electron process with simultaneous emission of three electrons.

10.
J Appl Microbiol ; 117(2): 397-404, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24807242

RESUMEN

AIM: The aim of the study was to develop test methods and evaluate survival of Francisella philomiragia cells and MS2 bacteriophage after exposure to PES-Solid (a solid source of peracetic acid) formulations with or without surfactants. METHODS AND RESULTS: Francisella philomiragia cells (≥7·6 log10 CFU) or MS2 bacteriophage (≥6·8 log10 PFU) were deposited on seven different test materials and treated with three different PES-Solid formulations, three different preneutralized samples and filter controls at room temperature for 15 min. There were 0-1·3 log10 CFU (<20 cells) of cell survival, or 0-1·7 log10 (<51 PFU) of bacteriophage survival in all 21 test combinations (organism, formulation and substrate) containing reactive PES-Solid. In addition, the microemulsion (Dahlgren Surfactant System) showed ≤2 log10 (100 cells) of viable F. philomiragia cells, indicating the microemulsion achieved <2 log10 CFU on its own. CONCLUSIONS: Three PES-Solid formulations and one microemulsion system (DSS) inactivated F. philomiragia cells and/or MS2 bacteriophage that were deposited on seven different materials. SIGNIFICANCE AND IMPACT OF THE STUDY: A test method was developed to show that reactive PES-Solid formulations and a microemulsion system (DSS) inactivated >6 log10 CFU/PFU F. philomiragia cells and/or MS2 bacteriophage on different materials.


Asunto(s)
Descontaminación/métodos , Desinfectantes/farmacología , Desinfección/métodos , Francisella/efectos de los fármacos , Levivirus/efectos de los fármacos , Ácido Peracético/farmacología , Viabilidad Microbiana/efectos de los fármacos , Tensoactivos
11.
J Appl Microbiol ; 115(2): 398-408, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23692445

RESUMEN

AIMS: To develop test methods and evaluate survival of Bacillus anthracis Ames, B. anthracis ∆Sterne and B. thuringiensis Al Hakam spores after exposure to PES-Solid (a solid source of peracetic acid), including PES-Solid formulations with bacteriostatic surfactants. METHODS AND RESULTS: Spores (≥ 7 logs) were dried on seven different test materials and treated with three different PES-Solid formulations (or preneutralized controls) at room temperature for 15 min. There was either no spore survival or less than 1 log (<10 spores) of spore survival in 56 of 63 test combinations (strain, formulation and substrate). Less than 2.7 logs (<180 spores) survived in the remaining seven test combinations. The highest spore survival rates were seen on water-dispersible chemical agent resistant coating (CARC-W) and Naval ship topcoat (NTC). Electron microscopy and Coulter analysis showed that all spore structures were intact after spore inactivation with PES-Solid. CONCLUSIONS: Three PES-Solid formulations inactivated Bacillus spores that were dried on seven different materials. SIGNIFICANCE AND IMPACT OF THE STUDY: A test method was developed to show that PES-Solid formulations effectively inactivate Bacillus spores on different materials.


Asunto(s)
Bacillus anthracis/efectos de los fármacos , Bacillus thuringiensis/efectos de los fármacos , Descontaminación/métodos , Desinfectantes/farmacología , Ácido Peracético/farmacología , Bacillus anthracis/ultraestructura , Bacillus thuringiensis/ultraestructura , Desinfectantes/química , Esporas Bacterianas/efectos de los fármacos , Esporas Bacterianas/ultraestructura
12.
J Appl Microbiol ; 113(5): 1037-51, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22897143

RESUMEN

AIMS: To develop test methods and evaluate the survival of Bacillus anthracis ∆Sterne and Bacillus thuringiensis Al Hakam spores after exposure to hot, humid air. METHODS AND RESULTS: Spores (>7 logs) of both strains were dried on six different test materials. Response surface methodology was employed to identify the limits of spore survival at optimal test combinations of temperature (60, 68, 77°C), relative humidity (60, 75, 90%) and time (1, 4, 7 days). No spores survived the harshest test run (77°C, 90% r.h., 7 days), while > 6·5 logs of spores survived the mildest test run (60°C, 60% r.h., 1 day). Spores of both strains inoculated on nylon webbing and polypropylene had greater survival rates at 68°C, 75% r.h., 4 days than spores on other materials. Electron microscopy showed no obvious physical damage to spores using hot, humid air, which contrasted with pH-adjusted bleach decontamination. CONCLUSIONS: Test methods were developed to show that hot, humid air effectively inactivates B. anthracis ∆Sterne and B. thuringiensis Al Hakam spores with similar kinetics. SIGNIFICANCE AND IMPACT OF THE STUDY: Hot, humid air is a potential alternative to conventional chemical decontamination.


Asunto(s)
Bacillus anthracis/aislamiento & purificación , Bacillus thuringiensis/aislamiento & purificación , Descontaminación/métodos , Calor , Humedad , Aire , Microscopía Electrónica de Transmisión , Esporas Bacterianas/aislamiento & purificación , Esporas Bacterianas/ultraestructura , Estadística como Asunto
13.
J Appl Microbiol ; 111(5): 1057-64, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21824240

RESUMEN

AIMS: To evaluate the inactivation of Bacillus anthracisΔSterne and Ames spores using electrochemically generated liquid-phase chlorine dioxide (eClO(2)) and compare two sporulation and decontamination methods with regard to cost, safety and technical constraints. METHODS AND RESULTS: Spores were prepared via agar and broth methods and subsequently inoculated and dried onto clean, autoclave-sterilized glass coupons. Bacillus anthracis spore inactivation efficacy was evaluated using the modified three-step method (AOAC 2008.05) and a single-tube extraction method. Spores (7·0 ± 0·5 logs) were inactivated within 1 min at room temperature using freshly prepared eClO(2). Bacillus anthracisΔSterne spores decreased in size after eClO(2) treatment as measured using a Beckman Coulter Multisizer. CONCLUSIONS: eClO(2) saturation of a hard surface was an effective B. anthracis sporicide. Broth sporulation and the single-tube extraction method required less time and fewer steps, yielded a higher percentage of phase-bright spores and showed higher spore recovery efficiency compared with AOAC 2008.05, making it more amenable to biosafety level 3 (BSL3) testing of virulent spores. SIGNIFICANCE AND IMPACT OF THE STUDY: Two test methods demonstrated the sporicidal efficacy of eClO(2). A new single-tube extraction test protocol for decontaminants was introduced.


Asunto(s)
Bacillus anthracis/efectos de los fármacos , Compuestos de Cloro/química , Descontaminación/métodos , Desinfectantes/química , Óxidos/química , Viabilidad Microbiana , Esporas Bacterianas/efectos de los fármacos
14.
J Appl Microbiol ; 105(5): 1604-13, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19146496

RESUMEN

AIMS: To compare physical properties of spores that were produced in broth sporulation media at greater than 10(8) spores ml(-1). METHODS AND RESULTS: Bacillus atrophaeus reproducibly sporulated in nutrient broth (NB) and sporulation salts. Microscopy measurements showed that the spores were 0.68 +/- 0.11 microm wide and 1.21 +/- 0.18 microm long. Coulter Multisizer (CM3) measurements revealed the spore volumes and volume-equivalent spherical diameters, which were 0.48 +/- 0.38 microm(3) and 0.97 +/- 0.07 microm, respectively. Bacillus cereus reproducibly sporulated in NB, sporulation salts, 200 mmol l(-1) glutamate and antifoam. Spores were 0.95 +/- 0.11 microm wide and 1.31 +/- 0.17 microm long. Spore volumes were 0.78 +/- 0.61 microm(3) and volume-equivalent spherical diameters were 1.14 +/- 0.11 microm. Bacillus atrophaeus spores were hydrophilic and B. cereus spores were hydrophobic. However, spore hydrophobicity was significantly altered after treatment with pH-adjusted bleach. CONCLUSIONS: The utility of a CM3 for both quantifying Bacillus spores and measuring spore sizes was demonstrated, although the volume between spore exosporium and spore coat was not measured. This study showed fundamental differences between spores from a Bacillus subtilis- and B. cereus-group species. SIGNIFICANCE AND IMPACT OF THE STUDY: This is useful for developing standard methods for broth spore production and physical characterization of both living and decontaminated spores.


Asunto(s)
Bacillus/fisiología , Medios de Cultivo/química , Bacillus/ultraestructura , Ácido Glutámico , Microscopía Electrónica , Sales (Química) , Esporas Bacterianas/fisiología , Esporas Bacterianas/ultraestructura
17.
Laryngorhinootologie ; 85(6): 444-7, 2006 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-16770841

RESUMEN

A 37-year-old female presented for surgery with central perforation of the eardrum with granulation. Mastoidectomy had been performed 18 years ago following chronic mastoiditis. As the clinical picture now suggested a suspected cholesteatoma, radiological imaging was performed. The CT scan revealed specification of the mastoid and the tympanic cavity. In addition, MRI scan showed signal enhancement in the same areas. However, the suspected cholesteatoma could not be confirmed intraoperatively. Pathohistology revealed a ceruminal gland adenoma. They are a rare phenomenon and should be distinguished from middle ear adenomas, pleomorph ceruminal gland adenomas, ceruminal gland adenocarcinomas and cylindromas of the ceruminal glands. Owing to a high recurrence rate, complete surgical removal is necessary. Despite its rare occurrence, a ceruminal gland adenoma must be taken into consideration in the differential diagnosis of individual cholesteatoma cases.


Asunto(s)
Adenoma/diagnóstico , Glándulas Apocrinas/patología , Carcinoma de Células Escamosas/diagnóstico , Cerumen , Conducto Auditivo Externo/patología , Neoplasias del Oído/diagnóstico , Oído Medio/patología , Neoplasias de las Glándulas Sudoríparas/diagnóstico , Adenoma/patología , Adenoma/cirugía , Adulto , Glándulas Apocrinas/cirugía , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/cirugía , Tejido Conectivo/patología , Tejido Conectivo/cirugía , Diagnóstico Diferencial , Conducto Auditivo Externo/cirugía , Neoplasias del Oído/patología , Neoplasias del Oído/cirugía , Oído Medio/cirugía , Femenino , Perdida Auditiva Conductiva-Sensorineural Mixta/diagnóstico , Perdida Auditiva Conductiva-Sensorineural Mixta/cirugía , Humanos , Aumento de la Imagen , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Imagen por Resonancia Magnética , Apófisis Mastoides/patología , Apófisis Mastoides/cirugía , Invasividad Neoplásica , Neoplasias de las Glándulas Sudoríparas/patología , Neoplasias de las Glándulas Sudoríparas/cirugía , Tomografía Computarizada por Rayos X , Perforación de la Membrana Timpánica/diagnóstico , Perforación de la Membrana Timpánica/cirugía
18.
Z Gastroenterol ; 43(8): 719-22, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16088769

RESUMEN

We report on two spontaneous cases of microangiopathic hemolytic anemia (MAHA) as first manifestation due to metastasized signet ring carcinoma, one of gastric and one of unknown origin. The patients presented with an acute onset of Coombs negative hemolytic anemia and fragmentocytes in the peripheral blood smear which are typical for MAHA. These case reports present MAHA as a rare paraneoplastic syndrome in patients with metastasized signet ring carcinoma. Parallel to symptomatic treatment we started chemotherapy treatment (ELF and PLF regimen, respectively). In both cases we were able to control the MAHA and cancer progression.


Asunto(s)
Anemia Hemolítica/etiología , Neoplasias de la Médula Ósea/secundario , Neoplasias Óseas/secundario , Carcinoma de Células en Anillo de Sello/secundario , Neoplasias Primarias Desconocidas , Síndromes Paraneoplásicos , Neoplasias Gástricas , Anemia Hemolítica/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Transfusión Sanguínea , Neoplasias de la Médula Ósea/diagnóstico , Neoplasias de la Médula Ósea/tratamiento farmacológico , Neoplasias Óseas/tratamiento farmacológico , Carcinoma de Células en Anillo de Sello/complicaciones , Carcinoma de Células en Anillo de Sello/tratamiento farmacológico , Carcinoma de Células en Anillo de Sello/cirugía , Gastrectomía , Humanos , Masculino , Persona de Mediana Edad , Síndromes Paraneoplásicos/diagnóstico , Neoplasias Gástricas/cirugía , Factores de Tiempo
19.
Toxicol In Vitro ; 19(2): 221-9, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15649636

RESUMEN

Bacillus anthracis (BA) is a spore forming bacterium and the causative agent of anthrax disease. Macrophages (Mphis) play a central role in anthrax disease. An important step in disease progression is the ability of BA to secrete lethal toxin (LeTx) that kills Mphis. LeTx is a heterodimer composed of protective antigen (PA) and lethal factor (LF). Researchers have shown that Mphi cell lines demonstrate differential susceptibility to purified LeTx; for example RAW264.7 and J774A.1 Mphis are sensitive to LeTx whereas IC-21 Mphis are resistant. Research has also suggested that exogenous factors, including other BA proteins, can influence the activity of LeTx. For this reason, the objective of the current work was to examine if RAW264.7, J774A.1, and IC-21 Mphis demonstrated differential susceptibility when cultured with a LeTx-producing strain of BA. Here, we co-cultured Mphis with LeTx+ Vollum 1B (V1B) spores for >15 h and assayed for Mphi cell death by morphology, trypan blue (TB) staining, neutral red (NR) activity, and lactate dehydrogenase (LDH) activity in the culture media. Following the addition of V1B spores, necrosis (approximately 50% mortality) was observed in RAW264.7 and J774A.1 Mphis at 7.5 and 10 h, respectively. By 15 h, both RAW264.7 and J774A.1 Mphis demonstrated 100% mortality. In contrast, IC-21 Mphis, under identical culture conditions, remained viable (98%) and activated throughout the course of the experiment (>24 h). The mechanism of RAW264.7 cell death appeared to involve LeTx because the V1B-induced cytotoxicity was dose-dependently reversed by the addition of anti-PA antibody to the culture media. These observations suggest there is differential susceptibility of Mphi cell lines to the LeTx+ V1B strain of BA. Further development of this in vitro model may be useful to further characterize the interactions between Mphis and BA spores.


Asunto(s)
Carbunco/microbiología , Antígenos Bacterianos/toxicidad , Bacillus anthracis/patogenicidad , Toxinas Bacterianas/toxicidad , Macrófagos/efectos de los fármacos , Animales , Carbunco/inmunología , Antígenos Bacterianos/inmunología , Bacillus anthracis/metabolismo , Toxinas Bacterianas/inmunología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Técnicas de Cocultivo , Macrófagos/patología , Necrosis , Esporas Bacterianas
20.
Leukemia ; 18(9): 1460-7, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15284854

RESUMEN

Bone marrow fibrosis (MF) has been shown to indicate therapy failure in Ph(+) chronic myeloid leukemia (CML). However, the results on the development of MF during interferon-alpha therapy of CML are controversial. The significance of the interferon dose has not been considered as yet. In total, 627 bone marrow biopsies taken prospectively from 200 patients with CML recruited in two studies using different doses of interferon-alpha +/- low-dose cytosine arabinoside were examined for MF before and during therapy. The results showed that the risk of MF depended significantly on the interferon-alpha dose applied (P<0.000005). MF progressed during low-dose therapy (3 x 5 x 10(6) IU/week), but was prevented from progression when applying high dose (5 x 10(6) IU/m(2)/per day). MF disappeared when high-dose interferon-alpha was combined with low-dose cytosine arabinoside (P<0.000005). The risk of death markedly increased when MF occurred or progressed (P<0.0009), independent of all other prognostic factors evaluated including the cytogenetic response. In conclusion, the effectiveness of interferon-alpha on MF depends on the treatment intensity. MF reverses when combining high-dose interferon-alpha with low-dose cytosine arabinoside, but progresses when applying low-dose interferon-alpha. MF appears to be a significant early indicator of ineffective therapy in CML.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Médula Ósea/patología , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Mielofibrosis Primaria/etiología , Adulto , Biopsia , Aberraciones Cromosómicas , Ensayos Clínicos Controlados como Asunto , Citarabina/administración & dosificación , Análisis Citogenético , Progresión de la Enfermedad , Resistencia a Antineoplásicos , Femenino , Humanos , Interferón-alfa/administración & dosificación , Leucemia Mielógena Crónica BCR-ABL Positiva/mortalidad , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Tasa de Supervivencia
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