Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 109
Filtrar
2.
Ann Nucl Med ; 36(7): 623-633, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35534690

RESUMEN

AIM: In the CheckRad-CD8 trial patients with locally advanced head and neck squamous cell cancer are treated with a single cycle of induction chemo-immunotherapy (ICIT). Patients with pathological complete response (pCR) in the re-biopsy enter radioimmunotherapy. Our goal was to study the value of F-18-FDG PET/CT in the prediction of pCR after induction therapy. METHODS: Patients treated within the CheckRad-CD8 trial that additionally received FDG- PET/CT imaging at the following two time points were included: 3-14 days before (pre-ICIT) and 21-28 days after (post-ICIT) receiving ICIT. Tracer uptake in primary tumors (PT) and suspicious cervical lymph nodes (LN +) was measured using different quantitative parameters on EANM Research Ltd (EARL) accredited PET reconstructions. In addition, mean FDG uptake levels in lymphatic and hematopoietic organs were examined. Percent decrease (Δ) in FDG uptake was calculated for all parameters. Biopsy of the PT post-ICIT acquired after FDG-PET/CT served as reference. The cohort was divided in patients with pCR and residual tumor (ReTu). RESULTS: Thirty-one patients were included. In ROC analysis, ΔSUVmax PT performed best (AUC = 0.89) in predicting pCR (n = 17), with a decline of at least 60% (sensitivity, 0.77; specificity, 0.93). Residual SUVmax PT post-ICIT performed best in predicting ReTu (n = 14), at a cutpoint of 6.0 (AUC = 0.91; sensitivity, 0.86; specificity, 0.88). Combining two quantitative parameters (ΔSUVmax ≥ 50% and SUVmax PT post-ICIT ≤ 6.0) conferred a sensitivity of 0.81 and a specificity of 0.93 for determining pCR. Background activity in lymphatic organs or uptake in suspected cervical lymph node metastases lacked significant predictive value. CONCLUSION: FDG-PET/CT can identify patients with pCR after ICIT via residual FDG uptake levels in primary tumors and the related changes compared to baseline. FDG-uptake in LN + had no predictive value. TRIAL REGISTRY: ClinicalTrials.gov identifier: NCT03426657.


Asunto(s)
Fluorodesoxiglucosa F18 , Neoplasias de Cabeza y Cuello , Linfocitos T CD8-positivos , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/terapia , Humanos , Inmunoterapia , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Radiofármacos
3.
Nature ; 605(7911): 653-658, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35364602

RESUMEN

Before the Perseverance rover landing, the acoustic environment of Mars was unknown. Models predicted that: (1) atmospheric turbulence changes at centimetre scales or smaller at the point where molecular viscosity converts kinetic energy into heat1, (2) the speed of sound varies at the surface with frequency2,3 and (3) high-frequency waves are strongly attenuated with distance in CO2 (refs. 2-4). However, theoretical models were uncertain because of a lack of experimental data at low pressure and the difficulty to characterize turbulence or attenuation in a closed environment. Here, using Perseverance microphone recordings, we present the first characterization of the acoustic environment on Mars and pressure fluctuations in the audible range and beyond, from 20 Hz to 50 kHz. We find that atmospheric sounds extend measurements of pressure variations down to 1,000 times smaller scales than ever observed before, showing a dissipative regime extending over five orders of magnitude in energy. Using point sources of sound (Ingenuity rotorcraft, laser-induced sparks), we highlight two distinct values for the speed of sound that are about 10 m s-1 apart below and above 240 Hz, a unique characteristic of low-pressure CO2-dominated atmosphere. We also provide the acoustic attenuation with distance above 2 kHz, allowing us to explain the large contribution of the CO2 vibrational relaxation in the audible range. These results establish a ground truth for the modelling of acoustic processes, which is critical for studies in atmospheres such as those of Mars and Venus.

4.
Eur Rev Med Pharmacol Sci ; 26(1): 284-290, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35049006

RESUMEN

OBJECTIVE: The COVID-19 pandemic and the measures accompanying it have been accused of having a negative influence on the frequency and methods of treatment of various diseases including head and neck cancer (HNSCC). To go further into this assumption, the diagnoses made, and treatments performed at one of Germany's largest head and neck cancer centres were evaluated. PATIENTS AND METHODS: This study consisted of one single centre and involved a retrospective review of all patients with newly diagnosed or recurrent HNSCC. The diagnosis and treatment methods used in the pre-COVID-19 time period between March 1st, 2019, and March 1st, 2020, were analysed and compared with the COVID-19 time period from April 1st, 2020, until April 1st, 2021. The primary objective was defined as the number of malignant diagnoses and the secondary objectives as the disease stage and the time to therapy. RESULTS: A total of 612 patients (160♀; mean 63 yrs.) were included. 319 patients (52%) were treated in the pre-COVID-19 time. The two groups did not differ in terms of age (p=0.304), gender (p=0.941), presence of recurrent disease (p=0.866), tumour subsite (p=0.194) or the duration from presentation to the multidisciplinary tumour board until start of therapy (p=0.202). There were no significant differences in the T stage (p=0.777), N stage (p=0.067) or UICC stage (p=0.922). During the pre-COVID-19 period more patients presented with distant metastases (n= 23 vs. n=8; p=0.011). CONCLUSIONS: This study shows that there was no significant change in either the number and severity of HNSCC diagnoses or the time until start of therapy at this large head and neck cancer centre as a result of the COVID-19 pandemic.


Asunto(s)
COVID-19/epidemiología , Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/epidemiología , Pandemias , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Instituciones Oncológicas , Diagnóstico Tardío/tendencias , Femenino , Alemania , Neoplasias de Cabeza y Cuello/terapia , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello , Adulto Joven
5.
J Cancer Educ ; 37(4): 1186-1193, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-33400206

RESUMEN

Human papillomavirus (HPV) is a disease that exacts substantial costs in human life and public health expenditures. Fortunately, a vaccine exists that can mitigate these costs. This study reports the development and evaluation of the intervention designed to overcome these barriers by using culturally grounded narratives to promote HPV vaccination. Women's Stories (WS) targets women over the age of 18 and was originally successfully validated for use among college students resulting in NCI recognition. WS was adapted for touch pad delivery in Planned Parenthood clinics where a randomized clinical trial was conducted in 8 clinics in 3 cities. Two hundred seventeen women were randomly assigned to treatment and control, completing pretest and posttest surveys. This study examined data from the immediate posttest. An intent to treat analysis was conducted using a generalized linear mixed modeling approach using a multinomial link and accounting for repeated measures by site. Results demonstrate significant short-term effects on vaccine intentions and vaccine self-efficacy. When compared to control group participants, women in the treatment condition more likely to intend to get the shot today/the day of interview (p < 0.01), as well as in 1 (p < 0.01) and 6 (p < 0.01) months and had greater self-efficacy to receive the HPV vaccination (B = 0.54; p = 0.0002). These results are promising for the potential impact of the intervention in clinical settings as well as providing a model for overcoming lack of awareness and vaccine resistance in other segments of the population.


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Neoplasias del Cuello Uterino , Adulto , Centros Comunitarios de Salud , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Intención , Persona de Mediana Edad , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/uso terapéutico , Aceptación de la Atención de Salud , Neoplasias del Cuello Uterino/prevención & control , Vacunación
6.
Eur Rev Med Pharmacol Sci ; 24(3): 1211-1218, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32096150

RESUMEN

OBJECTIVE: This study aimed to clarify the impact of delayed adjuvant therapy on the outcome of HPV associated oropharyngeal squamous cell carcinoma (HPV-OPSCC). PATIENTS AND METHODS: A total of 157 patients with HPV-OPSCC treated by surgery and adjuvant radiotherapy or chemoradiation therapy were analyzed retrospectively. We divided participants into two groups implementing adjuvant therapy within or after 50 days. Primary endpoints were the rates of locoregional recurrence and distant metastases, overall survival, and disease-specific survival. RESULTS: Adjuvant treatment began within 50 days (average: 38.8 days) in 79 cases compared to 78 cases after 50 days (average: 71.5 days). Five-year overall survival was 85.7% and 87.4% (p=0.588), the rates of local and regional recurrence were 3.8% and 6.4% (p=0.455) and of distant metastases 5.1% and 9% (p=0.369) implementing adjuvant treatment within or later than 50 days, respectively. CONCLUSIONS: These results suggest that adjuvant therapy initiated later than seven weeks after primary ablative surgery may still be effective HPV-OPSCC.


Asunto(s)
Quimioradioterapia/métodos , Genes p16 , Neoplasias Orofaríngeas/cirugía , Infecciones por Papillomavirus/cirugía , Tiempo de Tratamiento/tendencias , Anciano , Estudios de Cohortes , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Orofaríngeas/mortalidad , Neoplasias Orofaríngeas/terapia , Infecciones por Papillomavirus/mortalidad , Infecciones por Papillomavirus/terapia , Estudios Retrospectivos , Tasa de Supervivencia/tendencias
7.
Med Vet Entomol ; 32(4): 504-508, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30003568

RESUMEN

The identification of bloodmeal sources in triatomine bugs (Hemiptera: Reduviidae) is important in understanding vector-host associations and in measuring the risk for Chagas' disease transmission. The bloodmeal sources of triatomines infected with Trypanosoma cruzi (Trypanosomatida: Trypanosomatidae) caught in houses in central Brazil (Goiás State and the Federal District) were investigated during 2012-2014. Mitochondrial cytochrome b amplicons were used to identify bloodmeals through high-resolution melting and DNA sequencing. Most bugs were found to have fed on either humans (45.7%) or chickens (43.1%). Human blood was detected in Triatoma sordida (n = 22/50 bugs), Triatoma pseudomaculata (n = 7/11 bugs), Panstrongylus megistus (n = 10/24 bugs), Panstrongylus geniculatus (n = 1/3 bugs) and Rhodnius neglectus (n = 18/28 bugs) (all: Hemiptera: Reduviidae). Sequencing identified Necromys (Rodentia: Cricetidae) mouse blood in P. geniculatus and Tropidurus (Squamata: Tropiduridae) lizard blood in T. pseudomaculata and T. sordida. These findings reveal new vector-host associations. The present results suggest frequent contact between humans and T. cruzi-infected triatomines in central Brazil and indicate that Chagas' disease transmission by native vectors is an ongoing threat.


Asunto(s)
Enfermedad de Chagas/transmisión , Pollos/sangre , Sigmodontinae/sangre , Triatominae/fisiología , Trypanosoma cruzi/fisiología , Animales , Brasil , Gatos , Pollos/parasitología , ADN/química , ADN/metabolismo , Perros , Colorantes Fluorescentes , Congelación , Interacciones Huésped-Parásitos , Calor , Vivienda , Humanos , Lagartos/sangre , Zarigüeyas , Reacción en Cadena de la Polimerasa , Ovinos , Sigmodontinae/parasitología , Triatominae/parasitología
8.
Biochim Biophys Acta Bioenerg ; 1858(4): 318-324, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28131736

RESUMEN

The structure of phycobiliproteins of the cyanobacterium Acaryochloris marina was investigated in buffer solution at physiological temperatures, i.e. under the same conditions applied in spectroscopic experiments, using small angle neutron scattering. The scattering data of intact phycobiliproteins in buffer solution containing phosphate can be well described using a cylindrical shape with a length of about 225Å and a diameter of approximately 100Å. This finding is qualitatively consistent with earlier electron microscopy studies reporting a rod-like shape of the phycobiliproteins with a length of about 250 (M. Chen et al., FEBS Letters 583, 2009, 2535) or 300Å (J. Marquart et al., FEBS Letters 410, 1997, 428). In contrast, phycobiliproteins dissolved in buffer lacking phosphate revealed a splitting of the rods into cylindrical subunits with a height of 28Å only, but also a pronounced sample aggregation. Complementary small angle neutron and X-ray scattering experiments on phycocyanin suggest that the cylindrical subunits may represent either trimeric phycocyanin or trimeric allophycocyanin. Our findings are in agreement with the assumption that a phycobiliprotein rod with a total height of about 225Å can accommodate seven trimeric phycocyanin subunits and one trimeric allophycocyanin subunit, each of which having a height of about 28Å. The structural information obtained by small angle neutron and X-ray scattering can be used to interpret variations in the low-energy region of the 4.5K absorption spectra of phycobiliproteins dissolved in buffer solutions containing and lacking phosphate, respectively.


Asunto(s)
Cianobacterias/química , Transferencia de Energía , Dispersión del Ángulo Pequeño , Difracción de Neutrones , Ficobiliproteínas/química , Difracción de Rayos X
9.
Ann Oncol ; 26(6): 1238-1244, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25762352

RESUMEN

BACKGROUND: Recent evidence suggests that ionizing radiation may be associated with unexpected side-effects in melanoma patients treated with concomitant BRAF inhibitors. A large multicenter analysis was carried out to generate reliable safety data and elucidate the mechanism. METHODS: A total of 161 melanoma patients from 11 European skin cancer centers were evaluated for acute and late toxicity, of whom 70 consecutive patients received 86 series of radiotherapy with concomitant BRAF inhibitor therapy. To further characterize and quantify a possible radiosensitization by BRAF inhibitors, blood samples of 35 melanoma patients were used for individual radiosensitivity testing by fluorescence in situ hybridization of chromosomal breaks after ex vivo irradiation. RESULTS: With radiotherapy and concomitant BRAF inhibitor therapy the rate of acute radiodermatitis ≥2° was 36% and follicular cystic proliferation was seen in 13% of all radiotherapies. Non-skin toxicities included hearing disorders (4%) and dysphagia (2%). Following whole-brain radiotherapy, rates of radiodermatitis ≥2° were 44% and 8% (P < 0.001) for patients with and without BRAF inhibitor therapy, respectively. Concomitant treatment with vemurafenib induced acute radiodermatitis ≥2° more frequently than treatment with dabrafenib (40% versus 26%, P = 0.07). In line with these findings, analysis of chromosomal breaks ex vivo indicated significantly increased radiosensitivity for patients under vemurafenib (P = 0.004) and for patients switched from vemurafenib to dabrafenib (P = 0.002), but not for patients on dabrafenib only. No toxicities were reported after stereotactic treatment. CONCLUSION: Radiotherapy with concomitant BRAF inhibitor therapy is feasible with an acceptable increase in toxicity. Vemurafenib is a more potent radiosensitizer than dabrafenib.


Asunto(s)
Quimioradioterapia/métodos , Imidazoles/uso terapéutico , Indoles/uso terapéutico , Melanoma/terapia , Oximas/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Radiocirugia , Neoplasias Cutáneas/terapia , Sulfonamidas/uso terapéutico , Irradiación Corporal Total , Adulto , Anciano , Anciano de 80 o más Años , Europa (Continente) , Estudios de Factibilidad , Femenino , Humanos , Imidazoles/efectos adversos , Indoles/efectos adversos , Masculino , Melanoma/enzimología , Melanoma/patología , Persona de Mediana Edad , Oximas/efectos adversos , Inhibidores de Proteínas Quinasas/efectos adversos , Proteínas Proto-Oncogénicas B-raf/metabolismo , Tolerancia a Radiación , Fármacos Sensibilizantes a Radiaciones/efectos adversos , Radiodermatitis/etiología , Radiodermatitis/prevención & control , Radiocirugia/efectos adversos , Estudios Retrospectivos , Neoplasias Cutáneas/enzimología , Neoplasias Cutáneas/patología , Sulfonamidas/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Vemurafenib , Irradiación Corporal Total/efectos adversos , Adulto Joven
10.
Horm Metab Res ; 46(13): 943-9, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25054436

RESUMEN

Colesevelam improves glycemic control in patients with type 2 diabetes when added to existing metformin-, sulfonylurea-, or insulin-based regimens. We evaluated colesevelam's effects in subjects on stable pioglitazone-based therapy. This 24-week multicenter, double-blind, randomized, placebo-controlled study enrolled adults with type 2 diabetes who had suboptimal glycemic control [HbA1c ≥ 58 mmol/mol (7.5%) and ≤ 80 mmol/mol (9.5%)] on pioglitazone (30 or 45 mg) with or without 1-2 other oral antidiabetes medications. Subjects were randomized to colesevelam 3.8 g/day (n = 280) or placebo (n = 282) added to existing pioglitazone-based therapy. Primary efficacy variable was mean change in HbA1c from baseline to Week 24. Secondary variables included safety and tolerability, fasting plasma glucose changes, glycemic responses, and lipid profile. Tertiary variables included lipid particle profile changes by nuclear magnetic resonance. Colesevelam decreased HbA1c [least-squares mean treatment difference, - 3.5 mmol/mol (- 0.32%); p < 0.001] and fasting plasma glucose (- 14.7 mg/dl; p<0.001) vs. placebo at Week 24. More subjects receiving colesevelam vs. placebo achieved HbA1c reduction ≥ 7.7 mmol/mol (0.7%) (40% vs. 25%; p<0.001) or HbA1c < 53 mmol/mol (7.0%) (21% vs. 13%; p = 0.012). Colesevelam also decreased total cholesterol (mean treatment difference, - 6.5%), LDL-cholesterol (- 16.4%), non-HDL-cholesterol (- 9.8%), apolipoprotein B (- 8.8%), and total LDL particle concentration, and increased apolipoprotein A1 (+3.4%) and triglycerides (median treatment difference, + 11.3%) vs. placebo (all p < 0.001). There were no serious drug-related adverse events, and the majority of adverse events were mild or moderate. In subjects with type 2 diabetes inadequately controlled with pioglitazone-based therapy, add-on colesevelam therapy improved glycemic control and lipid parameters and was well tolerated. ClinicalTrials.gov identifier: NCT00789750.


Asunto(s)
Alilamina/análogos & derivados , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Tiazolidinedionas/efectos adversos , Tiazolidinedionas/uso terapéutico , Alilamina/efectos adversos , Alilamina/uso terapéutico , Glucemia/metabolismo , Clorhidrato de Colesevelam , Demografía , Diabetes Mellitus Tipo 2/sangre , Quimioterapia Combinada , Ayuno/sangre , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Análisis de los Mínimos Cuadrados , Lípidos/sangre , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Pioglitazona , Placebos , Resultado del Tratamiento
11.
Strahlenther Onkol ; 190(4): 408-10, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24452817

RESUMEN

BACKGROUND: Temozolomide (TMZ) is an alkylating agent used in chemoradiotherapy and adjuvant chemotherapy regimens for treatment of newly diagnosed or recurrent glioblastoma. In Germany alone, 900,000 daily doses of the drug are prescribed each year. Therefore, all severe side effects of TMZ, even those rarely observed, are relevant to radiotherapists. MATERIALS AND METHODS: We report a case of severe drug-induced toxic hepatitis that developed during chemoradiotherapy with TMZ in a patient with glioblastoma multiforme. RESULTS: Transaminase elevation was observed after 5 weeks of TMZ treatment, followed by severe jaundice symptoms which only subsided 2 months later. These findings were consistent with diagnosis of the mixed hepatic/cholestatic type of drug-induced toxic hepatitis. Due to the early termination of treatment, no life-threatening complications occurred in our patient. However, rare reports of encephalopathy and fatality as complications of TMZ therapy can be found in the literature. CONCLUSION: When using TMZ for treatment of glioblastoma, monitoring of liver enzyme levels should be performed twice weekly to prevent fatal toxic hepatitis. In the case of any drug-induced hepatitis, TMZ must be discontinued immediately.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/diagnóstico , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Dacarbazina/análogos & derivados , Antineoplásicos Alquilantes/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Dacarbazina/efectos adversos , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , Temozolomida , Resultado del Tratamiento
12.
Rev Sci Instrum ; 82(9): 094102, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21974601

RESUMEN

A laser ablation-miniature mass spectrometer (LA-MMS) for the chemical and isotopic measurement of rocks and minerals is described. In the LA-MMS method, neutral atoms ablated by a pulsed laser are led into an electron impact ionization source, where they are ionized by a 70 eV electron beam. This results in a secondary ion pulse typically 10-100 µs wide, compared to the original 5-10 ns laser pulse duration. Ions of different masses are then spatially dispersed along the focal plane of the magnetic sector of the miniature mass spectrometer (MMS) and measured in parallel by a modified CCD array detector capable of detecting ions directly. Compared to conventional scanning techniques, simultaneous measurement of the ion pulse along the focal plane effectively offers a 100% duty cycle over a wide mass range. LA-MMS offers a more quantitative assessment of elemental composition than techniques that detect ions directly generated by the ablation process because the latter can be strongly influenced by matrix effects that vary with the structure and geometry of the surface, the wavelength of the laser beam, and the not well characterized ionization efficiencies of the elements in the process. The above problems attendant to the direct ion analysis has been minimized in the LA-MMS by analyzing the ablated neutral species after their post-ionization by electron impaction. These neutral species are much more abundant than the directly ablated ions in the ablated vapor plume and are, therefore, expected to be characteristic of the chemical composition of the solid. Also, the electron impact ionization of elements is well studied and their ionization cross sections are known and easy to find in databases. Currently, the LA-MMS limit of detection is 0.4 wt.%. Here we describe LA-MMS elemental composition measurements of various minerals including microcline, lepidolite, anorthoclase, and USGS BCR-2G samples. The measurements of high precision isotopic ratios including (41)K/(39)K (0.077 ± 0.004) and (29)Si/(28)Si (0.052 ± 0.006) in these minerals by LA-MMS are also described. The LA-MMS has been developed as a prototype instrument system for space applications for geochemical and geochronological measurements on the surface of extraterrestrial bodies.


Asunto(s)
Isótopos/química , Rayos Láser , Espectrometría de Masas/instrumentación , Miniaturización/instrumentación , Medio Ambiente Extraterrestre/química , Marte , Factores de Tiempo
13.
Biochemistry ; 50(13): 2650-9, 2011 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-21370880

RESUMEN

Annexin A1 is a multifunctional, calcium-dependent phospholipid binding protein involved in a host of processes including inflammation, regulation of neuroendocrine signaling, apoptosis, and membrane trafficking. Binding of annexin A1 to glycans has been implicated in cell attachment and modulation of annexin A1 function. A detailed characterization of the glycan binding preferences of annexin A1 using carbohydrate microarrays and surface plasmon resonance served as a starting point to understand the role of glycan binding in annexin A1 function. Glycan array analysis identified annexin A1 binding to a series of sulfated oligosaccharides and revealed for the first time that annexin A1 binds to sulfated non-glycosaminoglycan carbohydrates. Using heparin/heparan sulfate microarrays, highly sulfated heparan sulfate/heparin were identified as preferred ligands of annexin A1. Binding of annexin A1 to heparin/heparan sulfate is calcium- but not magnesium-dependent. An in-depth structure-activity relationship of annexin A1-heparan sulfate interactions was established using chemically defined sugars. For the first time, a calcium-dependent heparin binding protein was characterized with such an approach. N-Sulfation and 2-O-sulfation were identified as particularly important for binding.


Asunto(s)
Anexina A1/metabolismo , Heparina/metabolismo , Heparitina Sulfato/metabolismo , Polisacáridos/metabolismo , Animales , Anexina A1/genética , Calcio/metabolismo , Glicosaminoglicanos/química , Glicosaminoglicanos/metabolismo , Heparina/química , Heparitina Sulfato/química , Cinética , Ligandos , Ratones , Análisis por Micromatrices/métodos , Concentración Osmolar , Proteínas Recombinantes/metabolismo , Relación Estructura-Actividad , Resonancia por Plasmón de Superficie
14.
Nervenarzt ; 82(4): 481-95, 2011 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-21079908

RESUMEN

Spasticity is one of the major causes of functional impairment in adults with lesions of the central nervous system. For instance, approximately 30% of post-stroke patients suffer from different degrees of spasticity with possible consecutive impairments. Numerous studies or meta-analyses showed that local injections of botulinum toxin in spastic muscles lead to dose-dependent reduction in muscle tone and improvement of passive movements (e. g. facilitated care), especially following repeated injections.However, country-specific regulations and patient-remote administration in German health care often do not allow adequate provision of this therapy. Thus, the present consensus statement based on the EBM analyses of the published international literature tries to highlight recent advances and the standard in the field of local spasticity treatment, aiming to facilitate communication between the decision makers and German reimbursement institutions in health care. Prior to initiation of BoNT-A injections, patient-oriented goals should be identified in a multiprofessional context to assure realistic goals for this specific treatment and patient expectations. In Germany for the treatment of focal spasticity following stroke three products have been approved: Botox® (Pharm Allergan, Ettlingen), Dysport® (Ipsen Pharma, Ettlingen) and Xeomin® (Merz Pharma, Frankfurt/Main). For all preparations safety has been repeatedly shown. Functional improvements have also been illustrated for selected patients concerning hand/arm function and gait. The dose per muscle and the selection of muscles to be injected have to be individualized according to the patient's symptoms and should be accompanied by modern neurorehabilitative therapies such as redression or repetitive activation of the injected and antagonistic muscles.


Asunto(s)
Toxinas Botulínicas/uso terapéutico , Espasticidad Muscular/tratamiento farmacológico , Neurología/normas , Guías de Práctica Clínica como Asunto , Adulto , Antidiscinéticos/uso terapéutico , Alemania , Humanos
15.
J Drug Educ ; 40(1): 11-36, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21038761

RESUMEN

This article takes a systematic approach to reviewing substance use prevention programs introduced in elementary school (K-6th grade). Previous studies evaluating such programs among elementary school students showed mixed effects on subsequent substance use and related psychosocial factors. Thirty published evaluation studies of 24 elementary school-based substance use prevention programs were reviewed. The study selection criteria included searching for program evaluations from 1980 to 2008. Among 27 evaluation studies that examined program effects on substance use, 56% (n = 15) found significant decreases. In addition, programs most often demonstrated effects on increasing negative substance use attitudes, increasing knowledge, decreasing perceptions of prevalence rates (i.e., descriptive norms), and improving resistance skills. These results have implications for the appropriateness and value of introducing substance use prevention programs to youth in elementary school.


Asunto(s)
Conductas Relacionadas con la Salud , Educación en Salud , Servicios de Salud Escolar/organización & administración , Trastornos Relacionados con Sustancias/prevención & control , Niño , Humanos , Trastornos Relacionados con Sustancias/psicología
16.
Science ; 325(5936): 58-61, 2009 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-19574383

RESUMEN

The Phoenix mission investigated patterned ground and weather in the northern arctic region of Mars for 5 months starting 25 May 2008 (solar longitude between 76.5 degrees and 148 degrees ). A shallow ice table was uncovered by the robotic arm in the center and edge of a nearby polygon at depths of 5 to 18 centimeters. In late summer, snowfall and frost blanketed the surface at night; H(2)O ice and vapor constantly interacted with the soil. The soil was alkaline (pH = 7.7) and contained CaCO(3), aqueous minerals, and salts up to several weight percent in the indurated surface soil. Their formation likely required the presence of water.


Asunto(s)
Hielo , Marte , Agua , Carbonato de Calcio , Medio Ambiente Extraterrestre , Concentración de Iones de Hidrógeno , Robótica , Nave Espacial , Temperatura
17.
Science ; 325(5936): 64-7, 2009 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-19574385

RESUMEN

The Wet Chemistry Laboratory on the Phoenix Mars Lander performed aqueous chemical analyses of martian soil from the polygon-patterned northern plains of the Vastitas Borealis. The solutions contained approximately 10 mM of dissolved salts with 0.4 to 0.6% perchlorate (ClO4) by mass leached from each sample. The remaining anions included small concentrations of chloride, bicarbonate, and possibly sulfate. Cations were dominated by Mg2+ and Na+, with small contributions from K+ and Ca2+. A moderately alkaline pH of 7.7 +/- 0.5 was measured, consistent with a carbonate-buffered solution. Samples analyzed from the surface and the excavated boundary of the approximately 5-centimeter-deep ice table showed no significant difference in soluble chemistry.


Asunto(s)
Aniones , Cationes , Marte , Percloratos , Fenómenos Químicos , Medio Ambiente Extraterrestre , Concentración de Iones de Hidrógeno , Oxidación-Reducción , Solubilidad , Nave Espacial , Temperatura , Agua
18.
Science ; 325(5936): 61-4, 2009 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-19574384

RESUMEN

Carbonates are generally products of aqueous processes and may hold important clues about the history of liquid water on the surface of Mars. Calcium carbonate (approximately 3 to 5 weight percent) has been identified in the soils around the Phoenix landing site by scanning calorimetry showing an endothermic transition beginning around 725 degrees C accompanied by evolution of carbon dioxide and by the ability of the soil to buffer pH against acid addition. Based on empirical kinetics, the amount of calcium carbonate is most consistent with formation in the past by the interaction of atmospheric carbon dioxide with liquid water films on particle surfaces.


Asunto(s)
Carbonato de Calcio , Marte , Dióxido de Carbono , Precipitación Química , Medio Ambiente Extraterrestre , Calor , Concentración de Iones de Hidrógeno , Nave Espacial , Agua
19.
Science ; 325(5936): 68-70, 2009 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-19574386

RESUMEN

The light detection and ranging instrument on the Phoenix mission observed water-ice clouds in the atmosphere of Mars that were similar to cirrus clouds on Earth. Fall streaks in the cloud structure traced the precipitation of ice crystals toward the ground. Measurements of atmospheric dust indicated that the planetary boundary layer (PBL) on Mars was well mixed, up to heights of around 4 kilometers, by the summer daytime turbulence and convection. The water-ice clouds were detected at the top of the PBL and near the ground each night in late summer after the air temperature started decreasing. The interpretation is that water vapor mixed upward by daytime turbulence and convection forms ice crystal clouds at night that precipitate back toward the surface.


Asunto(s)
Hielo , Marte , Vapor , Atmósfera , Medio Ambiente Extraterrestre , Nave Espacial , Temperatura , Factores de Tiempo
20.
Inflamm Res ; 57(11): 542-6, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19109748

RESUMEN

OBJECTIVE AND DESIGN: Autoregulative function in the brain gets relevant in hypodynamic conditions of a sepsis syndrome. We investigated the temporal pattern and dose dependent effects of LPS-induced shock on autoregulative function in rats. MATERIAL AND SUBJECTS: Chloralose-anesthetized and mechanically ventilated male CD-rats (n = 30). TREATMENT: Animals were subjected to vehicle, 1 or 5 mg/kg b.w. lipopolysaccharide (LPS) from E. coli given intravenously. METHODS: Autoregulative function was tested repeatedly with a carotid compression technique assessing the transient hyperemic response ratio (THRR) in the cortex with laser Doppler flowmetry up to 270 min. THRR data from exsanguination experiments served as controls. RESULTS: Despite lower blood pressure levels in the high dose group (control: 114 +/- 7 mmHg; 1 mg/kg LPS group: 82 +/- 16 mmHg; 5 mg/kg LPS group: 62 +/- 16 mmHg; p < 0.05) progressive cerebral hyperemia occurred similarly in both groups. Compared to exsanguinations experiments autoregulative compensation for lower blood pressure levels was lacking in the high LPS dose group at the end of experiments. CONCLUSIONS: Cerebral autoregulation was affected by LPS-induced shock supporting the notion of vasoregulative failure in endotoxic shock.


Asunto(s)
Encéfalo/fisiopatología , Homeostasis , Choque Séptico/fisiopatología , Animales , Circulación Cerebrovascular , Modelos Animales de Enfermedad , Masculino , Óxido Nítrico/biosíntesis , Ratas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...