Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 216
Filtrar
1.
J Dairy Sci ; 105(12): 9738-9750, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36207185

RESUMEN

Selection for feed efficiency (FE) is a hot topic in dairy cow breeding. Dry matter intake (DMI) and residual energy intake (REI) are mostly discussed as new selection traits. Selection for lower DMI or REI seems to increase FE if other traits, such as milk yield or health, are not affected negatively. However, genetic relationships with other traits have not been adequately investigated because of the difficulties in recording sufficient feed intake data for genetic evaluations. The aim of this study was to examine the genetic relationships between FE-related traits and liability to diseases throughout lactation. First, heritabilities for all traits are presented. Subsequently, genetic correlations between DMI, energy-corrected milk yield, energy balance (EB), and REI on the one hand and 3 disease categories (mastitis, claw and leg diseases, and all diseases) on the other throughout lactation in German Holstein (GH) dairy cows are illustrated. Production and health data from the projects optiKuh and eMissionCow were used. Data consisted of weekly observations recorded over a 325-wk period in 2,387 GH and over a 300-wk period in 632 Fleckvieh (FV) primiparous and multiparous dairy cows from 13 dairy research farms in Germany. Variance and covariance components were estimated univariately or bivariately with linear random regression models for production data and threshold random regression models for health data. Heritabilities for DMI, EB, and REI were on average 0.17 and 0.15, 0.14 and 0.15, as well as 0.11 and 0.14 in GH and FV, respectively. Heritabilities on the underlying scale for mastitis, claw and leg diseases, and all diseases were on average 0.17 and 0.16, 0.18 and 0.12, as well as 0.15 and 0.11 in GH and FV, respectively. In GH, almost all genetic correlations were negative, especially in early lactation. Within the first 50 d in milk, genetic correlations between DMI and REI on the one hand and disease categories on the other ranged from -0.25 to -0.14 for mastitis, from -0.31 to -0.13 for claw and leg diseases, and from -0.58 to -0.30 for all diseases. Consequently, selection for lower DMI or REI could lead to a higher liability to diseases, especially in early lactation. A possibility to mitigate these undesirable side effects could be lactation stage-specific selection for FE. For FV, further studies with more data are needed to assess genetic relationships.


Asunto(s)
Enfermedades de los Bovinos , Mastitis , Femenino , Bovinos , Animales , Lactancia/genética , Ingestión de Energía , Leche , Metabolismo Energético/genética , Ingestión de Alimentos/genética , Mastitis/veterinaria , Alimentación Animal , Dieta/veterinaria , Enfermedades de los Bovinos/genética
2.
J Dairy Sci ; 104(10): 10970-10978, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34334207

RESUMEN

Residual energy intake (REI) is an often-suggested trait for direct selection of dairy cows for feed efficiency. Cows with lower REI seem to be more efficient but are also in a more severe negative energy balance (EB), especially in early lactation. A negative EB leads to a higher liability to diseases. Due to this fact, this study aims to investigate the genetic relationship between REI and liability to diseases. Health and production data were recorded from 1,370 German Holstein dairy cows from 8 research farms over a period of 2 yr. We calculated 2 phenotypes for REI that considered the following energy sinks: milk energy content, metabolic body weight, body weight change, body condition score, and body condition score change. Genetic parameters were estimated with threshold or linear random regression models from days in milk (DIM) 1 to 305. Heritabilities for REI, EB, and all diseases ranged from 0.12 to 0.39, 0.15 to 0.31, and 0.09 to 0.20, respectively. Genetic correlations between selected DIM for REI and EB were higher for adjacent DIM than for more distant DIM. Pearson correlation coefficients between estimated breeding values (EBV) for REI and EB varied between 0.47 and 0.81; they were highest in mid lactation. Correlations between EBV for all diseases and REI as well as EB were negative, with lowest values in early lactation. Within the first 50 DIM, proportions of diseased days for cows with lowest EBV for REI were almost twice as high as for cows with highest EBV for REI. In conclusion, selecting dairy cows for lower REI should be treated with caution because of an unfavorable relationship with liability to diseases, especially in early lactation.


Asunto(s)
Ingestión de Energía , Lactancia , Animales , Bovinos/genética , Femenino , Peso Corporal , Metabolismo Energético/genética , Lactancia/genética , Leche
3.
J Dairy Sci ; 104(1): 628-643, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33162077

RESUMEN

Dairy cow efficiency is increasingly important for future breeding decisions. The efficiency is determined mostly by dry matter intake (DMI). Reducing DMI seems to increase efficiency if milk yield remains the same, but resulting negative energy balance (EB) may cause health problems, especially in early lactation. Objectives of this study were to examine relationships between DMI and liability to diseases. Therefore, cow effects for DMI and EB were correlated with cow effects for 4 disease categories throughout lactation. Disease categories were mastitis, claw and leg diseases, metabolic diseases, and all diseases. In addition, this study presents relative percentages of diseased cows per days in milk (DIM), repeatability, and cow effect correlations for disease categories across DIM. A total of 1,370 German Holstein (GH) and 287 Fleckvieh (FV) primiparous and multiparous dairy cows from 12 dairy research farms in Germany were observed over a period of 2 yr. Farm staff and veterinarians recorded health data. We modeled health and production data with threshold random regression models and linear random regression models. From DIM 2 to 305 average daily DMI was 22.1 kg/d in GH and 20.2 kg/d in FV. Average weekly EB was 2.8 MJ of NEL/d in GH and 0.6 MJ of NEL/d in FV. Most diseases occurred in the first 20 DIM. Multiparous cows were more susceptible to diseases than primiparous cows. Relative percentages of diseased cows were highest for claw and leg diseases, followed by metabolic diseases and mastitis. Repeatability of disease categories and production traits was moderate to high. Cow effect correlations for disease categories were higher for adjacent lactation stages than for more distant lactation stages. Pearson correlation coefficients between cow effects for DMI, as well as EB, and disease categories were estimated from DIM 2 to 305. Almost all correlations were negative in GH, especially in early lactation. In FV, the course of correlations was similar to GH, but correlations were mostly more negative in early lactation. For the first 20 DIM, correlations ranged from -0.31 to 0.00 in GH and from -0.42 to -0.01 in FV. The results illustrate that future breeding for dairy cow efficiency should focus on DMI and EB in early lactation to avoid health problems.


Asunto(s)
Alimentación Animal , Enfermedades de los Bovinos/prevención & control , Industria Lechera , Metabolismo Energético , Animales , Bovinos , Dieta/veterinaria , Resistencia a la Enfermedad , Femenino , Alemania , Lactancia , Leche , Análisis de Regresión
4.
Z Rheumatol ; 78(9): 859-862, 2019 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-31506792

RESUMEN

Based on the case of a 33-year-old female patient with Löfgren's syndrome and skin changes in the region of a tattoo, this article describes tattoo sarcoidosis as a special manifestation of cutaneous sarcoidosis. Papulonodular changes that are strictly confined to a tattoo are highly suspicious for tattoo sarcoidosis. Interestingly, tattoo sarcoidosis is commonly associated with the involvement of other organs.


Asunto(s)
Sarcoidosis , Tatuaje , Adulto , Femenino , Humanos , Sarcoidosis/diagnóstico , Sarcoidosis/etiología , Piel/patología , Tatuaje/efectos adversos
5.
Rev Sci Instrum ; 89(10): 10C108, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30399817

RESUMEN

Electron-lattice coupling strength governs the energy transfer between electrons and the lattice and is important for understanding the material behavior under highly non-equilibrium conditions. Here we report the results of employing time-resolved electron diffraction at MeV energies to directly study the electron-lattice coupling strength in 40-nm-thick polycrystalline copper excited by femtosecond optical lasers. The temporal evolution of lattice temperature at various pump fluence conditions were obtained from the measurements of the Debye-Waller decay of multiple diffraction peaks. We observed the temperature dependence of the electron-lattice relaxation time which is a result of the temperature dependence of electron heat capacity. Comparison with two-temperature model simulations reveals an electron-lattice coupling strength of (0.9 ± 0.1) × 1017 W/m3/K for copper.

6.
Sci Total Environ ; 619-620: 1022-1029, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29734580

RESUMEN

The reduction of external loads of phosphorus (P) is the main action to control eutrophication in lakes. However, the elimination of these sources is not always sufficient for lakes' recovery, because the P accumulated in the sediment can be released for decades after it has accumulated. Thus, to restore a lake, it is also necessary to reduce its internal P loading. For this, it is essential to know the composition of P in the sediment to evaluate the potential P availability. In this study, the forms of P in the sediment of two reservoirs in a semiarid tropical region were investigated. The forms of P were determined by fractionation, sorting out the forms in loosely sorbed P (P-Water), reductant-soluble P (P-BD), metal oxide-bound P (P-NaOH), P bound to organic matter (P-Humic), calcium-bound P (P-HCl) and residual P (P-residual). The sediment was collected in September 2016 and sliced in situ. The total amount of P forms in the sediment varied from 5mgkg-1 to 349mgkg-1 in the Gargalheiras Reservoir and from 12mgkg-1 to 371mgkg-1 in the Cruzeta Reservoir. Despite some variation in amounts at different depths, the general range of fractions in Gargalheiras and Cruzeta was: P-BD>P-NaOH>P-HCl>P-water>P-Residual>P-Humic. In both reservoirs, the predominant form was BD, followed by NaOH and HCl. The first two forms are available and released easily, making them bioavailable for eutrophication processes and thus phytoplankton growth.

7.
Surg Endosc ; 31(6): 2566-2572, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-27670649

RESUMEN

BACKGROUND: Esophageal bougination is a worldwide standard endoscopic procedure. Clinical methods and recommendations are based on clinical experiences only. Mechanical properties have never been described. Aim of the study was to establish a realistic ex vivo training model. Therefore, detailed assessment of relevant mechanical features of esophageal bougination should be evaluated ex vivo and in patient setting and correlated against. PATIENTS AND METHODS: A three-step concept was used to evaluate mechanical properties at stenosis level. First, insertion forces were evaluated in an ex vivo linear single stenosis model during steady mechanical insertion. Second, adding friction and properties of the pharynx and upper esophagus, the model was integrated in an artificial endoscopic training model (ELITE training model). Third, in vivo measurements were taken to correlate ex vivo data with parameters of a realistic patient setting. RESULTS: With the presented setup, we were able to assess insertion force and pressure levels in an artificial stricture using different sizes of commercially available standard bougies. In all models, there was a relevant increase in insertion force with higher stricture pressure levels. Insertion force levels in the ELITE model show higher levels compared to the linear stenosis model. Having regard to the maximum forces in patients, there is also a constant increase in mean insertion force according to higher bougie sizes, but lower forces were measured as in the ELITE model. DISCUSSION: The applied models are suitable to appraise mechanical properties of esophageal bougination in an ex vivo model and patient setting. Forces could be constituted reliable, significant increase was documented according to stenosis level and results were comparable to patient data. This was comparable to patient data. Further clinical evaluation in different kinds of stenosis is necessary.


Asunto(s)
Competencia Clínica , Estenosis Esofágica/cirugía , Cirugía Endoscópica por Orificios Naturales/educación , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Anatómicos
8.
Scand J Med Sci Sports ; 27(7): 692-703, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27167471

RESUMEN

This study investigated the pharmacokinetics of inhaled terbutaline at rest and after exercise in normal and hot ambient conditions with respect to doping analysis. Thirteen trained young men participated in the study. Urine and blood samples were collected after inhalation of 4 mg terbutaline during three trials: exercise in hot ambient conditions (30-35 °C) (EXH), exercise in normal ambient conditions (20-25 °C) (EX), and rest (20-25 °C) (R). Exercise consisted of 130 min at various intensities. Adjustment of urine concentrations of terbutaline to a specific gravity (USG) of 1.02 g/mL was compared with no adjustment. Area under the serum concentration-time curve within the first 6 h was higher for EX (27 ± 3 ng/mL/h) (P ≤ 0.01) and EXH (25 ± 4 ng/mL/h) (P ≤ 0.05) than for R (20 ± 3 ng/mL/h). When unadjusted for USG, urine concentrations of terbutaline after 4 h were different in the order EXH > EX > R (P ≤ 0.01). When unadjusted for USG, urine concentrations of terbutaline were 299 ± 151 ng/mL higher (P ≤ 0.001) after 4 h compared with adjusted concentrations in EXH. Excretion rate of terbutaline was higher (P ≤ 0.001) for EX than for EXH and R within the first 0-1½ h. In conclusion, EXHs results in higher urine concentrations of terbutaline. This should be considered when evaluating doping cases of terbutaline.


Asunto(s)
Ejercicio Físico/fisiología , Temperatura , Terbutalina/farmacocinética , Administración por Inhalación , Adulto , Estudios Cruzados , Doping en los Deportes , Humanos , Masculino , Terbutalina/sangre , Terbutalina/orina , Adulto Joven
9.
Neurogastroenterol Motil ; 28(4): 599-607, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26891170

RESUMEN

BACKGROUND: In eosinophilic esophagitis (EoE), dysphagia, which might reflect esophageal dysmotility, is the most common symptom. High-resolution manometry (HRM) has become widely accepted for evaluating esophageal motility disorders, but to date has been sparsely examined in EoE patients, particularly under therapy. The aim of this study was to evaluate HRM in symptomatic EoE-patients under topical steroid treatment. METHODS: In this prospective observational study, symptomatic EoE patients received HRM-examinations before and after 8 weeks of topical steroid treatment with budesonide. All HRM-abnormalities were assessed and interpreted according to the Chicago classification. The primary endpoint was the influence of topical steroid treatment on the intrabolus pressure (IBP). Clinical symptoms, endoscopic findings and histological esophageal eosinophilic load were also reported. KEY RESULTS: Twenty symptomatic EoE patients were included. Overall success of budesonide therapy was 85% regarding complete histologic remission and 80% regarding complete clinical remission. High-resolution manometry showed abnormal esophageal motility in 35% of patients at baseline, which was resolved after therapy in 86% of these patients. Most frequent HRM-findings were early pan-esophageal pressurizations and weak persitalsis. There was no significant reduction of the IBP under therapy (before: 12.5 ± 4.9 mmHg, after: 10.9 ± 2.9 mmHg; p = 0.119). CONCLUSIONS & INFERENCES: Although dysphagia is the leading symptom of EoE, HRM is able to identify esophageal motility disorders in only some EoE patients. Observed motility disorders resolve after successful treatment in almost all of these patients. Intrabolus pressure does not seem an optimal parameter for the monitoring of successful treatment response in EoE patients.


Asunto(s)
Esofagitis Eosinofílica/diagnóstico , Manometría/métodos , Adulto , Antiinflamatorios/uso terapéutico , Budesonida/uso terapéutico , Esofagitis Eosinofílica/tratamiento farmacológico , Femenino , Humanos , Masculino , Estudios Prospectivos
10.
Sci Total Environ ; 541: 1253-1268, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26476065

RESUMEN

To assess potential future impacts on shallow aquifers by leakage of natural gas from unconventional energy resource development it is essential to establish a reliable baseline. Occurrence of methane in shallow groundwater in Alberta between 2006 and 2014 was assessed and was ubiquitous in 186 sampled monitoring wells. Free and dissolved gas sampling and measurement approaches yielded comparable results with low methane concentrations in shallow groundwater, but in 28 samples from 21 wells methane exceeded 10mg/L in dissolved gas and 300,000 ppmv in free gas. Methane concentrations in free and dissolved gas samples were found to increase with well depth and were especially elevated in groundwater obtained from aquifers containing coal seams and shale units. Carbon isotope ratios of methane averaged -69.7 ± 11.1‰ (n=63) in free gas and -65.6 ± 8.9‰ (n=26) in dissolved gas. δ(13)C values were not found to vary with well depth or lithology indicating that methane in Alberta groundwater was derived from a similar source. The low δ(13)C values in concert with average δ(2)HCH4 values of -289 ± 44‰ (n=45) suggest that most methane was of biogenic origin predominantly generated via CO2 reduction. This interpretation is confirmed by dryness parameters typically >500 due to only small amounts of ethane and a lack of propane in most samples. Comparison with mud gas profile carbon isotope data revealed that methane in the investigated shallow groundwater in Alberta is isotopically similar to hydrocarbon gases found in 100-250 meter depths in the WCSB and is currently not sourced from thermogenic hydrocarbon occurrences in deeper portions of the basin. The chemical and isotopic data for methane gas samples obtained from Alberta groundwater provide an excellent baseline against which potential future impact of deeper stray gases on shallow aquifers can be assessed.

12.
Rapid Commun Mass Spectrom ; 28(15): 1691-6, 2014 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-24975249

RESUMEN

RATIONALE: Literature data on experimentally derived equilibrium stable carbon isotope fractionation (10(3) lnα(13) C) between H2 CO3 (*) (H2 CO3 + CO2(aq) ) and gaseous CO2 (CO2(g) ) are so far only available up to 60 °C and were typically determined at or near atmospheric pressures. Here we experimentally expand this dataset to temperature and pressure conditions close to the supercritical state for CO2 . The objective is to improve the applicability of stable carbon isotopes as a tracer in environments where such conditions prevail. METHODS: Eighteen stable carbon isotope laboratory experiments were conducted in a steel vessel. Deionised water that was acidified with hydrochloric acid (HCl, 1 N) to a pH of 2.4 was equilibrated with CO2(g) at pressures (pCO2 ) of 55 bar for durations between 2 and 188 h. The experiments were conducted at 20, 60, 80, 100 and 120 °C. H2 CO3 (*) and CO2(g) were sampled separately and their carbon isotope ratios were determined by isotope ratio mass spectrometry. RESULTS: At 20 °C, average 10(3) lnα(13) CH2CO3 * -CO2(g) values of -1.0 ± 0.1 ‰ were observed with a preference for (12) C in H2 CO3 (*) consistent with previous research. At elevated temperatures of 120 °C, 10(3) lnα(13) CH2CO3 * -CO2(g) values decreased to an average value of -0.7 ± 0.1 ‰. The resulting temperature dependence for carbon isotope fractionation between H2 CO3 (*) and CO2(g) was 10(3) lnα(13) CH2CO3 * -CO2(g) = (0.0025 ± 0.0004) T(°C) - (1.0 ± 0.03) ‰. Carbon isotope equilibrium between H2 CO3 (*) and CO2(g) was reached within reaction times of 18 h and mostly within 5 h or less. CONCLUSIONS: 10(3) lnα(13) CH2CO3 * -CO2(g) data are now available for temperatures up to 120 °C and for pressures of up to 55 bar. The results suggest that higher pCO2 levels possibly shorten carbon isotope equilibration times. These data are critically important for using δ(13) C values as tracers, for instance at geological CO2 sequestration sites and corresponding natural analogues.


Asunto(s)
Dióxido de Carbono/química , Isótopos de Carbono/química , Fraccionamiento Químico/métodos , Espectrometría de Masas/métodos , Isótopos de Carbono/análisis , Presión , Temperatura
15.
Digestion ; 88(3): 161-4, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24080585

RESUMEN

BACKGROUND: Barrett esophagus (BE) is a major risk factor for adenocarcinoma of the distal esophagus. Reliable detection of BE during upper endoscopy is therefore mandatory. According to most guidelines, diagnosis of BE requires both endoscopy and histology for confirmation. However, since adenocarcinomas were also described in patients with indeterminate BE, i.e. endoscopic visible columnar metaplasia but no histological confirmation of goblet cells or vice versa, debate has risen on the risk of malignancy and the need for endoscopic surveillance in such patients. PATIENTS AND METHODS: The study was aimed to assess long-term follow-up data on 209 patients with indeterminate BE (on histopathology or endoscopy) initially examined between 1999 and 2000. Patients or referring physicians were contacted concerning the most recent endoscopic and histopathological results. RESULTS: Follow-up data could be assessed in 149/209 patients (65.1%) after a mean follow-up period of 9.4 years (SD ±2.4 years). Neoplasia was not reported for any patient. The previous endoscopic-histopathological diagnoses could be confirmed in 3 patients only. In the group with endoscopic diagnosis of BE but no histopathological confirmation, BE was described histopathologically in 1 patient during follow-up. CONCLUSION: Persistence of indeterminate BE is poor during long-term follow up. The risk of cancer appears to be negligible. Hence, surveillance of these patients appears equivocal.


Asunto(s)
Adenocarcinoma/patología , Esófago de Barrett/patología , Neoplasias Esofágicas/patología , Lesiones Precancerosas/patología , Adenocarcinoma/diagnóstico , Esófago de Barrett/diagnóstico , Neoplasias Esofágicas/diagnóstico , Esofagoscopía , Femenino , Estudios de Seguimiento , Células Caliciformes/patología , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Lesiones Precancerosas/diagnóstico , Pronóstico
16.
Int J Cancer ; 132(12): 2820-32, 2013 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-23225306

RESUMEN

Dysregulated apoptotic pathways are regarded as major reasons for chemoresistance development as a particular challenge in ovarian cancer therapy. In search of molecular factors affecting human ovarian cancer cell apoptosis and, consequently, patient survival, we examined tumors of 103 platinum-/taxane-treated ovarian cancer patients by mRNA-array hybridization, qPCR, and immunohistochemistry. We identified high expression of crystallin αB (CRYAB), a proposed negative regulator of tumor necrosis factor-related apoptosis inducing ligand (TRAIL)-mediated apoptosis. By Kaplan Meier analysis, this factor turned out to be significantly associated with poor patient outcome [overall survival (OS) p = 0.001, recurrence-free survival (RFS) p = 0.003]. Elevated hazard ratios (HR) were estimated with regard to OS (HR = 2.11, 95% CI 1.10-4.06) and RFS (HR = 1.92, 95% CI 1.07-3.47) in multivariable analyses. These associations were confirmed in independent, publicly available mRNA data comprising 431 patients for OS (p < 0.001) and 413 for RFS (p < 0.001). Our findings were validated by studying apoptotic events in cultured human ovarian cancer cells which were stably transfected to express elevated CRYAB levels. These data emphasized the crucial role of CRYAB in human ovarian cancer biology since TRAIL- as well as cisplatin-induced apoptosis was significantly impaired as a function of enhanced CRYAB expression. Taken together, we identified CRYAB as an independent biomarker for unfavourable outcome of human ovarian cancer patients. Since TRAIL is currently tested as anti-cancer drug and large proportions of the present patient cohort displayed low CRYAB levels in their tumors, CRYAB may enable the selection of patient subgroups benefiting most from TRAIL-containing therapy.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Biomarcadores de Tumor/genética , Cisplatino/farmacología , Neoplasias Ováricas/genética , Ligando Inductor de Apoptosis Relacionado con TNF/farmacología , Cadena B de alfa-Cristalina/genética , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Caspasa 3/metabolismo , Línea Celular Tumoral , Activación Enzimática/efectos de los fármacos , Femenino , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/patología , Pronóstico , ARN Mensajero/genética , ARN Mensajero/metabolismo , Cadena B de alfa-Cristalina/metabolismo
17.
Br J Dermatol ; 167(4): 787-93, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22578221

RESUMEN

BACKGROUND: The barrier perturbation pattern and molecular markers of inflammation upon tandem repeated irritation in chronologically aged skin have not been previously studied. OBJECTIVES: We aimed to investigate the barrier impairment kinetic and in vivo cytokine profile following sequential irritation with sodium lauryl sulfate (SLS) and undiluted toluene (Tol) in aged compared with young skin. METHODS: Four fields on the volar forearm of healthy aged and young volunteers (median age, respectively, 63.9 and 32.6 years) were sequentially exposed to 0.5% SLS and undiluted toluene in a controlled tandem repeated irritation test; an adjacent nontreated field served as control. The permeability barrier function was monitored by repeated measurements of transepidermal water loss (TEWL), capacitance and erythema every 24 h up to 96 h. The stratum corneum cytokines were harvested by sequential tape stripping and quantified by multiplex bead array and enzyme-linked immunosorbent assay. RESULTS: Compared with young skin, aged skin was characterized by delayed and/or less pronounced alterations in the visual irritation score, TEWL, chromametry a*-value and capacitance, assessed by the respective Δ-values for each parameter and monitoring time point. In both groups, exposure to SLS/SLS, SLS/Tol and Tol/SLS resulted in decreased interleukin (IL)-1α levels, whereas the application of Tol/Tol induced an increase in IL-1α. Furthermore, decreased IL-1 receptor antagonist (IL-1RA) levels and a lower IL-1RA/IL-1α ratio were found following repeated exposure to the irritants. CONCLUSIONS: Our results provide evidence for selective alterations in the cytokine profile and distinct barrier impairment kinetic following tandem repeated irritation with SLS and Tol in aged compared with young skin in vivo.


Asunto(s)
Citocinas/metabolismo , Dermatitis Irritante/etiología , Epidermis/efectos de los fármacos , Envejecimiento de la Piel/efectos de los fármacos , Piel/efectos de los fármacos , Dodecil Sulfato de Sodio/toxicidad , Tensoactivos/toxicidad , Adulto , Anciano , Agua Corporal/metabolismo , Dermatitis Irritante/metabolismo , Ensayo de Inmunoadsorción Enzimática , Epidermis/metabolismo , Eritema/inducido químicamente , Femenino , Humanos , Interleucina-1alfa/metabolismo , Masculino , Persona de Mediana Edad , Receptores Tipo I de Interleucina-1/antagonistas & inhibidores , Receptores Tipo I de Interleucina-1/metabolismo , Solventes/toxicidad , Tolueno/toxicidad , Adulto Joven
19.
Endoscopy ; 44(3): 251-7, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22261749

RESUMEN

BACKGROUND AND STUDY AIMS: The accurate diagnosis of indeterminate pancreaticobiliary strictures presents a clinical dilemma. Probe-based confocal laser endomicroscopy (pCLE) offers real-time in vivo microscopic tissue examination that may increase sensitivity for the detection of malignancy. the objective of this study was to develop and validate a standard descriptive classification of pcle in the pancreaticobiliary system. PATIENTS AND METHODS: A total of 102 patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) with pCLE to assess indeterminate pancreaticobiliary strictures were enrolled in a multicenter registry; 89 of these patients were evaluable. Information and data on the following were collected prospectively: clinical, ERCP, tissue sampling, pCLE, and follow-up. A uniform classification of pCLE findings ("Miami Classification") was developed, consisting of a set of image interpretation criteria. Thereafter, these criteria were tested through blinded consensus review of 112 randomized pCLE videos from 47 patients, and inter-observer variability was assessed in 42 patients . RESULTS: A consensus definition of the specific criteria of biliary and pancreatic pCLE findings for indeterminate strictures was developed. Single-image interpretation criteria did not have a high enough sensitivity for predicting malignancy. However, combining two or more criteria significantly increased the sensitivity and predictive values. The characteristics most suggestive of malignancy included the following: thick white bands (>20 µm), or thick dark bands (>40 µm), or dark clumps or epithelial structures. These provided sensitivity, specificity, positive predictive value, and negative predictive value of 97%, 33%, 80%, and 80% compared with 48%, 100%, 100%, and 41% for standard tissue sampling methods. Inter-observer variability was moderate for most criteria. CONCLUSION: The Miami Classification enables a structured, uniform, and reproducible description of pancreaticobiliary pCLE. Combining individual characteristics improves the sensitivity for the detection of malignancy.


Asunto(s)
Adenocarcinoma/diagnóstico , Neoplasias de los Conductos Biliares/diagnóstico , Conductos Biliares Intrahepáticos/patología , Colangiocarcinoma/diagnóstico , Neoplasias Hepáticas/diagnóstico , Microscopía Confocal , Conductos Pancreáticos/patología , Neoplasias Pancreáticas/diagnóstico , Adenocarcinoma/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades de los Conductos Biliares/clasificación , Enfermedades de los Conductos Biliares/etiología , Neoplasias de los Conductos Biliares/complicaciones , Colangiocarcinoma/complicaciones , Colangiopancreatografia Retrógrada Endoscópica , Constricción Patológica/clasificación , Constricción Patológica/etiología , Constricción Patológica/patología , Femenino , Humanos , Neoplasias Hepáticas/complicaciones , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Enfermedades Pancreáticas/clasificación , Enfermedades Pancreáticas/etiología , Neoplasias Pancreáticas/complicaciones , Valor Predictivo de las Pruebas
20.
J Intern Med ; 271(2): 155-65, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22142263

RESUMEN

Complex intracellular signalling networks integrate extracellular signals and convert them into cellular responses. In cancer cells, the tightly regulated and fine-tuned dynamics of information processing in signalling networks is altered, leading to uncontrolled cell proliferation, survival and migration. Systems biology combines mathematical modelling with comprehensive, quantitative, time-resolved data and is most advanced in addressing dynamic properties of intracellular signalling networks. Here, we introduce different modelling approaches and their application to medical systems biology, focusing on the identifiability of parameters in ordinary differential equation models and their importance in network modelling to predict cellular decisions. Two related examples are given, which include processing of ligand-encoded information and dual feedback regulation in erythropoietin (Epo) receptor signalling. Finally, we review the current understanding of how systems biology could foster the development of new treatment strategies in the context of lung cancer and anaemia.


Asunto(s)
Neoplasias Pulmonares/fisiopatología , Modelos Biológicos , Receptores de Eritropoyetina/fisiología , Transducción de Señal/fisiología , Biología de Sistemas/métodos , Anemia/inducido químicamente , Anemia/tratamiento farmacológico , Antineoplásicos/efectos adversos , Supervivencia Celular/fisiología , Citocinas/metabolismo , Eritropoyetina/efectos adversos , Eritropoyetina/metabolismo , Predicción , Humanos , Funciones de Verosimilitud , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/etiología , Matemática , Receptores de Eritropoyetina/antagonistas & inhibidores , Proteínas Recombinantes , Factores de Riesgo , Factores de Transcripción/fisiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...