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1.
Langenbecks Arch Surg ; 408(1): 90, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36790506

RESUMEN

BACKGROUND: Anastomotic leakages after esophagectomies continue to constitute significant morbidity and mortality. Intrathoracic anastomoses pose a high risk for mediastinitis, sepsis, and death, if a leak is not addressed timely and appropriately. However, there are no standardized treatment recommendations or algorithms as for how to treat these leakages. METHODS: The study included all patients at the University Hospital Regensburg, who developed an anastomotic leakage after esophagectomy with gastric pull-up reconstruction from 2007 to 2022. Patients receiving conventional treatment options for an anastomotic leakage (stents, drainage tubes, clips, etc.) were compared to patients receiving endoscopic vacuum-assisted closure (eVAC) therapy as their mainstay of treatment. Treatment failure was defined as cervical esophagostomy formation or death. RESULTS: In total, 37 patients developed an anastomotic leakage after esophagectomy with a gastric pull-up reconstruction. Twenty patients were included into the non-eVAC cohort, whereas 17 patients were treated with eVAC. Treatment failure was observed in 50% of patients (n = 10) in the non-eVAC cohort and in 6% of patients (n = 1) in the eVAC cohort (p < 0.05). The 90-day mortality in the non-eVAC cohort was 15% (n = 3) compared to 6% (n = 1) in the eVAC cohort. Cervical esophagostomy formation was required in 40% of cases (n = 8) in the non-eVAC cohort, whereas no patient in the eVAC cohort underwent cervical esophagostomy formation. CONCLUSION: eVAC therapy for leaking esophagogastric anastomoses appears to be superior to other treatment strategies as it significantly reduces morbidity and mortality. Therefore, we suggest eVAC as an essential component in the treatment algorithm for anastomotic leakages following esophagectomies, especially in patients with intrathoracic anastomoses.


Asunto(s)
Neoplasias Esofágicas , Terapia de Presión Negativa para Heridas , Humanos , Fuga Anastomótica/etiología , Fuga Anastomótica/cirugía , Esofagectomía/efectos adversos , Anastomosis Quirúrgica/efectos adversos , Endoscopía , Neoplasias Esofágicas/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
2.
Opt Lett ; 45(24): 6575-6578, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33325843

RESUMEN

We demonstrate the three-fold post-chirped-pulse-amplification (post-CPA) pulse compression of a high peak power laser pulse using allyl diglycol carbonate (CR39), which was selected as the optimal material for near-field self-phase modulation out of a set of various nonlinear plastic materials, each characterized with respect to its nonlinear refractive index and optical transmission. The investigated materials could be applied for further pulse compression at high peak powers, as well as for gain narrowing compensation within millijoule-class amplifiers. The post-CPA pulse compression technique was tested directly after the first CPA stage within the POLARIS laser system, with the compact setup containing a single 1 mm thick plastic sample and a chirped mirror pair, which enabled a substantial shortening of the compressed pulse duration and, hence, a significant increase in the laser peak power without any additional modifications to the existing CPA chain.

3.
Int J Colorectal Dis ; 32(7): 955-960, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28378155

RESUMEN

PURPOSE: To evaluate the impact of superior rectal artery (SRA) sparing technique on anastomotic leakage in laparoscopic sigmoidectomy for diverticular disease. MATERIAL AND METHODS: A retrospective multicenter analysis of all patients undergoing laparoscopic sigmoid resection for diverticular disease between 2002 and 2015 was conducted. Data were recorded in three hospitals: University Hospital Regensburg, Marienhospital Gelsenkirchen, and Städtisches Klinikum München Bogenhausen. The SRA was resected between 2002 and 2005. Since 2005, the artery was preserved in most cases. RESULTS: Two hundred sixty-seven patients were included. One hundred sixty patients presented with complicated diverticulitis (60%). The SRA was resected in 102 patients (group 1) and preserved in 157 patients (group 2, no data in eight cases). Anastomotic leakage occurred in 7% of patients in group 1 and 1.9% of patients in group 2 (p = 0.053). Duration of surgery was significantly shorter (157 vs. 183 min, p < 0.001) in group 2 patients. Length of hospital stay was without significant difference (group 1 8.2 days; group 2 8.3 days; p = 0.83). The conversion rate was higher in group 2 patients; however, the difference was not statistically significant (9 vs. 3%, p = 0.07). There was no significant difference between both groups regarding intraoperative complications and overall complication rate. The length of the resected specimen (19 vs. 21 cm, p = 0.001) was significantly shorter in group 2 patients. CONCLUSION: Preservation of the SRA seems to be associated with favorable outcome in patients undergoing laparoscopic sigmoid resection for diverticular disease.


Asunto(s)
Fuga Anastomótica/etiología , Colon Sigmoide/cirugía , Enfermedades Diverticulares/epidemiología , Enfermedades Diverticulares/cirugía , Laparoscopía/efectos adversos , Complicaciones Posoperatorias/etiología , Recto/irrigación sanguínea , Recto/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Demografía , Femenino , Humanos , Cuidados Intraoperatorios , Masculino , Persona de Mediana Edad , Análisis Multivariante , Complicaciones Posoperatorias/epidemiología , Cicatrización de Heridas , Adulto Joven
4.
Opt Express ; 22(9): 11228-35, 2014 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-24921820

RESUMEN

We present the first complete temporal and spatial characterization of the amplified spontaneous emission (ASE) of laser radiation generated by a diode-pumped high-power laser system. The ASE of the different amplifiers was measured independently from the main pulse and was characterized within a time window of -10ms ≤ t ≤ 10ms and an accuracy of up to 15fs around the main pulse. Furthermore, the focusability and the energy of the ASE from each amplifier was measured after recompression. Using our analysis method, the laser components, which need to be optimized for a further improvement of the laser contrast, can be identified. This will be essential for laser-matter interaction experiments requiring a minimized ASE intensity or fluence.

5.
Catheter Cardiovasc Interv ; 81(1): 133-41, 2013 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-22639434

RESUMEN

OBJECTIVE: This study evaluates short- and long-term results of CAS with the Gore Flow Reversal System (GFRS). BACKGROUND: Embolic protection devices are of fundamental importance in carotid artery stenting (CAS). Proximal protection has potential advantages compared with distal protection. Limited data are available regarding the safety of the proximal GFRS. METHODS: CAS was performed with the GFRS. Patients' neurological status was assessed during the intervention and at follow-up. Results of patients treated before 2006 were also compared to those of patients treated after 2006 because of changes in device design. RESULTS: CAS was performed in 86 patients with 87 stenoses (symptomatic in 37%). The procedure was technically successful in all cases. In 11 patients a transient periprocedural neurologic deficit occurred related to temporary cerebral flow compromise during balloon occlusion with complete resolution at completion of the procedure. The stroke/death rate at one month was 2.3% with a combined ipsilateral stroke and death rate at one year of 4.6%. There was no significant difference in event rates between the newer and older device version. Overall follow-up time was 484 ± 3.4 patient years with a range of 0 to 119 months. The average yearly ipsilateral stroke rate including the first 30 days was 0.96%. CONCLUSION: Our results demonstrate that CAS using the GFRS is safe whether the original or new device versions were used. The periprocedural stroke rate is at least as low as the stroke rate reported using distal protection. The long-term stroke rate after CAS is low.


Asunto(s)
Angioplastia/métodos , Estenosis Carotídea/terapia , Dispositivos de Protección Embólica/estadística & datos numéricos , Embolia Intracraneal/prevención & control , Stents , Anciano , Anciano de 80 o más Años , Angiografía/métodos , Angioplastia/efectos adversos , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/mortalidad , Estudios de Cohortes , Diseño de Equipo , Seguridad de Equipos , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Medición de Riesgo , Administración de la Seguridad/métodos , Índice de Severidad de la Enfermedad , Estadísticas no Paramétricas , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
6.
Opt Express ; 20(18): 20742-7, 2012 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-23037123

RESUMEN

We present the setup of a polarization rotating device and its adaption for high-power short-pulse laser systems. Compared to conventional halfwave plates, the all-reflective principle using three zero-phase shift mirrors provides a higher accuracy and a higher damage threshold. Since plan-parallel plates, e.g. these halfwave plates, generate postpulses, which could lead to the generation of prepulses during the subsequent laser chain, the presented device avoids parasitic pulses and is therefore the preferable alternative for high-contrast applications. Moreover the device is easily scalable for large beam diameters and its spectral reflectivity can be adjusted by an appropriate mirror coating to be well suited for ultra-short laser pulses.


Asunto(s)
Láseres de Estado Sólido , Refractometría/instrumentación , Procesamiento de Señales Asistido por Computador/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo
7.
Sci Rep ; 9(1): 16534, 2019 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-31712576

RESUMEN

We report on the successful implementation and characterization of a cryogenic solid hydrogen target in experiments on high-power laser-driven proton acceleration. When irradiating a solid hydrogen filament of 10 µm diameter with 10-Terawatt laser pulses of 2.5 J energy, protons with kinetic energies in excess of 20 MeV exhibiting non-thermal features in their spectrum were observed. The protons were emitted into a large solid angle reaching a total conversion efficiency of several percent. Two-dimensional particle-in-cell simulations confirm our results indicating that the spectral modulations are caused by collisionless shocks launched from the surface of the the high-density filament into a low-density corona surrounding the target. The use of solid hydrogen targets may significantly improve the prospects of laser-accelerated proton pulses for future applications.

8.
Urologe A ; 45(9): 1170-5, 2006 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-16767454

RESUMEN

PURPOSE: In this study we present the technique of a strictly retroperitoneal donor nephrectomy via a pararectal mini-incision. MATERIAL AND METHODS: Data of 34 living kidney donations were analyzed. All donors underwent a pararectal mini-incision and strictly retroperitoneal nephrectomy (MIDN). RESULTS: Total operation time, perioperative use of pain medication, length of hospital stay after successful mobilization, and return to full enteral nutrition and regular digestion were evaluated retrospectively. Total operation time for MIDN was 132+/-26 min. The total average application was 22.2+/-19.4 mg of opioid in morphine equivalent dosage (MED), 7.7+/-6.1 g metamizol, and 512+/-325 mg NSAR during hospital stay, which was 4.9+/-1.4 days. Patients were mobilized primarily 2.9+/-8.0 h after surgery. Mobility was achieved 33.8+/-15.8 h after surgery. Enteral nutrition with fluids was started after 1.9+/-7.0 h, full enteral nutrition was accomplished after 37.4+/-19.0 h, and normal digestion returned 58.6+/-23.0 h after the procedure. CONCLUSIONS: The strictly retroperitoneal nephrectomy via a mini-incision is an elegant, minimally traumatic, safe, and quickly learnable method, resulting in short hospital stays, good cosmetic results, and a low grade of complications.


Asunto(s)
Donadores Vivos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Nefrectomía/métodos , Adulto , Anciano , Ambulación Precoz , Nutrición Enteral , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Evaluación de Procesos y Resultados en Atención de Salud , Dolor Postoperatorio/etiología , Cuidados Posoperatorios , Complicaciones Posoperatorias/etiología , Recto/cirugía , Espacio Retroperitoneal/cirugía , Estudios Retrospectivos
9.
Cancer Res ; 46(7): 3704-10, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3458530

RESUMEN

A patient presented with a primary melanoma, Level IV, 2.5 mm thick; 30 excised lymph nodes were all negative for tumor. Four local recurrences followed in the ensuing 17 months. Tumor cells cultured at this time were epithelioid. Autoimmunization was followed by a disease-free interval of 15 months. Postimmunization, the patient's lymphocytes destroyed his melanoma cells in culture and were stimulated in mixed cell culture by his irradiated tumor cells. Cells grown from the relapsing tumor were spindle/dendritic with bizarre morphology and were not attacked by his lymphocytes in culture. Using a C' fixation technique, DR antigen profiles of the patient's B-cells and both tumor cell types showed that the immunizing tumor was positive for DR antigens 3, 5, and 8, none of which were present on his B-cells which had DR 2 and 4. Both B-cells and immunizing tumor cells were positive for DQ antigens. The relapsing tumor cells were positive for DR2 and negative for all other D region antigens tested. The evidence suggests that given a melanoma of heterogeneous cell population, autoimmunization against the predominant immunogenic cell inhibits tumor growth but allows the ascendance of a nonimmunogenic tumor cell type.


Asunto(s)
Antígenos de Neoplasias/análisis , Antígenos de Histocompatibilidad Clase II/inmunología , Melanoma/inmunología , Citotoxicidad Inmunológica , Antígenos HLA-DR , Humanos , Inmunidad Celular , Inmunización , Cariotipificación , Masculino , Melanoma/genética , Melanoma/patología , Persona de Mediana Edad , Recurrencia Local de Neoplasia/inmunología
10.
Clin Hemorheol Microcirc ; 64(4): 747-755, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27792004

RESUMEN

AIM: To determine different perfusion characteristics of histo-pathologically proven adenomas and carcinomas of the thyroid gland with CEUS and perfusion software. MATERIAL AND METHODS: Retrospective perfusion analysis of 25 patients with carcinomas and 41 cases of adenomas of the thyroid gland (30 males, 36 females; aged 18 - 85 years, mean 56 years). All cases were histologically analyzed. Perfusion analysis was independently performed using external perfusion software (VueBox®). TTP, mTT, Peak and Rise time were calculated. RESULTS: Lesions' sizes ranged from 0.2 to 10.2 cm in carcinomas (mean 2.18 cm), and from 0.6 to 5.0 cm in adenomas (mean 2.25 cm). In 20 out of 25 carcinomas that were evaluated with CEUS, a complete wash-out in the late venous phase was found. Adenomas showed wash-out at the border.Perfusion analysis in VueBox® revealed some parameters which tend to show differences between adenomas and carcinomas, however did not reach the level of significance.Median Peak in carcinomas was highest at the margins (2945 rU), and lowest in the surroundings (1110 rU). Mean Transit Time (mTT) values showed no differences between center, margin and surrounding.In adenomas healthy tissue showed higher mTT values compared to the center (24.6 vs. 20.7 sec). Median Peak was highest in the surrounding tissue and lowest in the margins (1999 vs. 1129 rU). No statistical differences could be found in the comparisons. CONCLUSION: CEUS with perfusion analysis offers new possibilities for the dynamic evaluation of micro-vascularization in thyroid adenomas and carcinomas. Using VueBox® the perfusion analysis of the arterial phase provides new parameters that help determine a lesion's malignancy or benignity. However a final assessment regarding malignancy and benignity of thyroid lesions using only CEUS and perfusion analysis of the arterial phase is not yet possible.


Asunto(s)
Medios de Contraste/uso terapéutico , Perfusión/métodos , Neoplasias de la Tiroides/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Microvasos , Persona de Mediana Edad , Neovascularización Patológica , Estudios Retrospectivos , Neoplasias de la Tiroides/patología , Adulto Joven
11.
Clin Hemorheol Microcirc ; 64(4): 735-745, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27767982

RESUMEN

OBJECTIVE: To evaluate the efficacy of strain elastography (SE) using semi-quantitative measurement methods compared to constrast enhanced ultrasound during liver tumor surgery (Io-CEUS) for dignity assessment of focal liver lesions(FLL). MATERIAL AND METHODS: Prospective data acquisition and retrospective analysis of US data of 100 patients (116 lesions) who underwent liver tumor surgery between 10/2010 and 03/2016. Retrospective reading of SE color patterns was performed establishing groups depending on dominant color (>50% blue = stiff, inhomogenous, >50% yellow/red/green = soft tissue). Semi-quantitative analysis was performed by Q-analysis based on a scale from 0 (soft) to 6 (stiff). 2 ROIs were placed centrally, 5 ROIs in the lesion's surrounding tissue. Io-CEUS was performed by bolus injection of 5-10 ml sulphurhexaflourid microbubbles evaluating wash-in- and -out- kinetics in arterial, portal venous and late phase. Histopathology after surgical resection served as goldstandard. RESULTS: 100 patients (m: 65, f: 35, mean age 60.5 years) with 116 liver lesions were included. Lesion's size ranged from 0.5 to 8.4 cm (mean 2.42 cm SD±1.44 cm). Postoperative histology showed 105 malignant and 11 benign lesions. Semi-quantitative analysis showed central indurations of >2.5 in 76/105 cases suggesting malignancy. 7 benign lesions displayed no central indurations correctly characterized benign by SE. ROC-analysis and Youden index showed a sensitivity of 72.4% and specificity of 63.6% assuming a cut-off of 2.5. Io-CEUS correctly characterized 103/105 as malignant. Sensitivity was 98%, specificity 72.7%. CONCLUSION: Strain elastography is a valuable tool for non-invasive characterization of FLLs. Semi-quantitative intratumoral stiffness values of >2.5 suggested malignancy. However, sensitivity of Io-CEUS in detecting malignant lesions was higher compared to SE. In conclusion SE should be considered for routine use during intraoperative US in addition to Io-CEUS for optimization of curative liver surgery.


Asunto(s)
Medios de Contraste/uso terapéutico , Diagnóstico por Imagen de Elasticidad/métodos , Neoplasias Hepáticas/cirugía , Ultrasonografía/métodos , Adulto , Anciano , Femenino , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos
12.
Clin Hemorheol Microcirc ; 61(1): 13-22, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-24898562

RESUMEN

BACKGROUND: To evaluate the impact of high-resolution contrast-enhanced ultrasound (CEUS) in combination with Color Coded and Power Doppler Sonography (CCDS/PD) in the preoperative differentiation of thyroid adenomas and thyroid carcinomas. METHODS: A total of 101 patients (55 female, median age 54 years) underwent surgery for thyroid adenoma and thyroid carcinoma. CCDS/PD and CEUS were performed in all patients by an experienced examiner using a multifrequency linear transducer (6-9 or 6-15 MHz) and were digitally stored. Reading of the ultrasound images was performed by two experienced radiologists in consensus. A histopathological evaluation was obtained as standard of reference in all patients. RESULTS: Altogether, 75 thyroid adenomas and 26 thyroid carcinomas were detected. Mean diameter of thyroid adenomas and thyroid carcinomas was 27 mm and 32 mm, respectively. The differences in microcirculation of thyroid adenomas and thyroid carcinomas were statistically highly significant (p <  0.01). Representative features for thyroid adenomas were either no wash-out or wash-out with persisting edge in late phase, for thyroid carcinomas a complete wash-out in late phase. Thus, a calculation of sensitivity, specificity, positive and negative predictive value of 81% , 92% , 97% and 63%, respectively, for the differentiation of benignity and malignancy was possible. CONCLUSIONS: Dynamic evaluation of microcirculation using CEUS and CCDS/PD enables a more reliable preoperative discrimination between thyroid adenomas and thyroid carcinomas.


Asunto(s)
Medios de Contraste/uso terapéutico , Neoplasias de la Tiroides/diagnóstico , Ultrasonografía Doppler en Color/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Periodo Preoperatorio , Neoplasias de la Tiroides/cirugía
13.
New Phytol ; 111(3): 483-489, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33874009

RESUMEN

Pure stands of Trifolium repens L. N.Z. Huia and Lolium perenne L. S32 and mixtures of various densities and frequencies were treated with sulphuric acd solutions of pH 2.5, 3.5 and 5.6. The species yield was recorded over five sequential harvests. Multifactorial response equations were used to describe the behaviour of the species yield as a function of acidity and the density of both species. Predictions, made through these models, showed that the response of yield of these species to simulated acid rain treatments Varied greatly depending on the planting density, the time of harvesting and on whether the plants were growing in monoculture or in mixture. This suggests that it is not sufficient to consider the effects of experimentally applied acid rain on single individuals or low density stands, since the results obtained will not reflect the response in a close canopy sward.

14.
Surgery ; 79(6): 682-5, 1976 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1064179

RESUMEN

Evidence of lymphocyte cytotoxicity against osteosarcoma, suggesting a degree of cell-mediated immunity, was found in the mother of a patient with osteogenic sarcoma. The mother was found to be HL-A identical to the patient and therefore was an ideal donor for whole lymphocytes. Lymphocytes were obtained from the mother by leukophoresis and were administered to the patient. Lymphocytotherapy transferred or re-established a delayed hypersensitivity response to mumps antigen and transferred the ability of killing osteogenic sarcoma cells in vitro. There was slight improvement in the patients' clinical condition coincident with the establishment of lymphocytoxicity in the patient. Loss of this capacity coincided with a rapid deterioration of the patient's condition.


Asunto(s)
Neoplasias Femorales/terapia , Inmunización Pasiva , Linfocitos/inmunología , Osteosarcoma/terapia , Adolescente , Femenino , Neoplasias Femorales/inmunología , Antígenos HLA , Humanos , Inmunidad Celular , Inmunoterapia/métodos , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/terapia , Metástasis de la Neoplasia , Osteosarcoma/inmunología , Trasplante Homólogo
15.
Toxicol Sci ; 47(1): 40-51, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10048152

RESUMEN

Hallmark signs of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) toxicity in rainbow trout sac fry, are yolk sac edema, hemorrhage, craniofacial malformation, and growth retardation culminating in mortality. Our objective was to determine the role of cardiovascular dysfunction in the development of this toxicity. An embryotoxic TCDD dose (385 pg/g egg) caused a progressive reduction in blood flow in rainbow trout sac fry manifested first and most dramatically in the 1st and 2nd branchial arches and vessels perfusing the lower jaw. Blood flow was reduced later in the infraorbital artery and occipital vein of the head as well as segmental vessels and caudal vein of the trunk. Reduced perfusion occurred last in gill branchial arteries involved with oxygen uptake and the subintestinal vein and vitelline vein involved with nutrient uptake. Although heart rate throughout sac fry development was not affected, heart size at 50 days post-fertilization (dpf) was reduced far more than body weight or length, suggesting that the progressive circulatory failure caused by TCDD is associated with reduced cardiac output. Craniofacial development was arrested near hatch, giving rise to craniofacial malformations in which the jaws and anterior nasal structures were underdeveloped. Unlike the medaka embryo, in which TCDD causes apoptosis in the medial yolk vein, endothelial cell death was not observed in rainbow trout sac fry. These findings suggest a primary role for arrested heart development and reduced perfusion of tissues with blood in the early-life stage toxicity of TCDD in trout.


Asunto(s)
Sistema Cardiovascular/efectos de los fármacos , Anomalías Craneofaciales/inducido químicamente , Oncorhynchus mykiss/fisiología , Dibenzodioxinas Policloradas/toxicidad , Teratógenos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Vasos Sanguíneos/efectos de los fármacos , Volumen Cardíaco/efectos de los fármacos , Edema/patología , Embrión no Mamífero , Corazón/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Etiquetado Corte-Fin in Situ , Oncorhynchus mykiss/anomalías , Oncorhynchus mykiss/embriología , Flujo Sanguíneo Regional/efectos de los fármacos , Factores de Tiempo , Membrana Vitelina/irrigación sanguínea , Membrana Vitelina/efectos de los fármacos , Cigoto
16.
Tissue Cell ; 24(4): 455-9, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1440571

RESUMEN

To assess gene induction in primary human fibroblasts, we have developed a method for cryopreservation of lung biopsies in liquid nitrogen. Fresh biopsies (n = 10) were chopped into 5 x 5 mm pieces and transferred into an ice-cold freezing medium. Biopsies were kept on ice for 15 min, followed by further cooling of the tissue to -70 degrees C. With this method, lung biopsies were preserved for more than 1 year before they were used for generating cell cultures. There was no significant difference in the biological responsiveness of fibroblasts generated from immediately cultured lung biopsies compared with those from cryopreserved tissue. The doubling rate of fibroblasts from fresh tissue was 23.6 +/- 1.1 hr; compared to 23.5 +/- 1.5 hr for fibroblasts generated from cryopreserved tissue. PDGF-BB enhanced de novo synthesis of DNA 100 times, in both the immediately cultured fibroblasts and those generated from cryopreserved biopsies. Macrophages, dendritic cells and endothelial cells could also be recovered from cryopreserved lung tissue. This method permits long-term storage of lung tissue and the possibility of establishing primary cell lines from the same tissue at later times without appreciable changes in their cellular biological characteristics.


Asunto(s)
Criopreservación/métodos , Pulmón/citología , Ciclo Celular , Células Cultivadas , Células Dendríticas , Hielo Seco , Fibroblastos/citología , Humanos , Macrófagos , Nitrógeno
17.
Environ Pollut ; 77(2-3): 205-10, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-15091960

RESUMEN

In common with other member states of UN-ECE, maps of critical loads of transboundary air pollutants are to be produced in the UK for different receptor (waters, soils and vegetation) types. These maps will be used as a tool for assessing different deposition scenarios with proposed pollution abatement strategies. This paper presents the methodology, results and a discussion of the principles used in applying critical loads of sulphur as a pilot study for soils in northern England. For the study area, critical load classes for soils vary with geology, drift cover and slope/elevation. The area of soils in which the critical load is exceeded varies significantly according to the type of deposition data utilised.

18.
Environ Pollut ; 90(3): 301-10, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-15091463

RESUMEN

The method used to produce a critical load map of acidity for soils in Great Britain is described. Critical loads were assigned to the dominant soil in each 1 km grid square of the UK national grid. Mineral soils were assigned a critical load based on mineralogy and chemistry, using approaches appropriate to UK conditions. Critical loads for peat soils are based primarily on a maximum acceptable reduction of peat pH, and results from laboratory equilibration studies. The map shows that soils with small critical loads (<0.5 kmol(c) ha(-1) year(-1)) i.e. highly sensitive to acidic deposition, dominate in the north and west of Britain; the south and east are dominated by soils with large critical loads, with small areas of more sensitive soils associated with sandy soil-forming materials. A modified critical load map illustrates the potential impact of agricultural liming on soil critical loads.

19.
Environ Pollut ; 87(2): 207-14, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-15091595

RESUMEN

Using a combination of soil, land use and geological information, a map of Great Britain has been derived which indicates the sensitivity of surface waters to acidification. For the geological information, a slightly modified version of an available map was used which indicated the sensitivity of groundwaters to acidification. For soils, 1-km databases of soil information for England and Wales and for Scotland were employed to map the soil sensitivity as determined by buffering capacity. The derived soils map was modified to take account of agricultural liming in arable and managed grassland areas using the ITE Land Classification. The final map of surface water sensitivity was obtained by using a geographic information system overlay procedure which enabled each combination of soil and geology sensitivity to be uniquely defined. The final sensitivity classification was based upon expert knowledge and the experience of a similar sensitivity mapping exercise for Wales.

20.
SAR QSAR Environ Res ; 25(4): 253-87, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24779615

RESUMEN

A rule-based expert system (ES) was developed to predict chemical binding to the estrogen receptor (ER) patterned on the research approaches championed by Gilman Veith to whom this article and journal issue are dedicated. The ERES was built to be mechanistically transparent and meet the needs of a specific application, i.e. predict for all chemicals within two well-defined inventories (industrial chemicals used as pesticide inerts and antimicrobial pesticides). These chemicals all lack structural features associated with high affinity binders and thus any binding should be low affinity. Similar to the high-quality fathead minnow database upon which Veith QSARs were built, the ERES was derived from what has been termed gold standard data, systematically collected in assays optimized to detect even low affinity binding and maximizing confidence in the negatives determinations. The resultant logic-based decision tree ERES, determined to be a robust model, contains seven major nodes with multiple effects-based chemicals categories within each. Predicted results are presented in the context of empirical data within local chemical structural groups facilitating informed decision-making. Even using optimized detection assays, the ERES applied to two inventories of >600 chemicals resulted in only ~5% of the chemicals predicted to bind ER.


Asunto(s)
Sistemas Especialistas , Sustancias Peligrosas/toxicidad , Relación Estructura-Actividad Cuantitativa , Antiinfecciosos/clasificación , Antiinfecciosos/toxicidad , Sustancias Peligrosas/clasificación , Plaguicidas/clasificación , Plaguicidas/toxicidad , Receptores de Estrógenos/metabolismo , Pruebas de Toxicidad/métodos
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