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1.
Phys Rev Lett ; 128(1): 011801, 2022 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-35061499

RESUMEN

Dark matter with Planck-scale mass (≃10^{19} GeV/c^{2}) arises in well-motivated theories and could be produced by several cosmological mechanisms. A search for multiscatter signals from supermassive dark matter was performed with a blind analysis of data collected over a 813 d live time with DEAP-3600, a 3.3 t single-phase liquid argon-based detector at SNOLAB. No candidate signals were observed, leading to the first direct detection constraints on Planck-scale mass dark matter. Leading limits constrain dark matter masses between 8.3×10^{6} and 1.2×10^{19} GeV/c^{2}, and ^{40}Ar-scattering cross sections between 1.0×10^{-23} and 2.4×10^{-18} cm^{2}. These results are interpreted as constraints on composite dark matter models with two different nucleon-to-nuclear cross section scalings.

2.
J Dairy Sci ; 104(8): 9205-9226, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34024600

RESUMEN

Dairy cows in modern production systems are at risk to develop metabolic disorders during the transition period. Reasons for individual differences in susceptibility, as well as the underlying pathomechanisms, are still only partially understood. The development of metaphylactic treatment protocols is needed. In this context, an on-farm prospective 3-fold blinded randomized study involving 80 German Holstein cows was performed throughout 1 yr. The trial involved a thorough recording of the production and clinical traits, clinical chemistry, and liver biopsies and blood and urine sampling at d 14 (mean: 12 d, range: 1-26 d) antepartum (AP), and d 7 (7, 4-13) and 28 (28, 23-34) postpartum (PP) for metabolomics analyses. Two groups received a treatment with butaphosphan and cyanocobalamin (BCC) at either the dosage recommended by the manufacturer or the double dosage (5 or 10 mL/100 kg of body weight 10% butaphosphan and 0.005% cyanocobalamin (Catosal, Bayer Animal Health), n = 20 in each group, parity: 4.2 ± 2.0 and 3.4 ± 1.3, respectively (mean ± SD)] and one group a placebo treatment (NaCl 0.9%, n = 40, parity: 4.0 ± 1.9). The animals were treated at 6 time points (7, 6, and 5 d AP, and 1, 2, and 3 d PP) via intravenous injection. Mass spectroscopy-based targeted metabolomics analysis of blood plasma and liver samples were performed using the AbsoluteIDQ p180 kit (Biocrates Life Sciences), whereas the urine samples were analyzed by nuclear magnetic resonance spectroscopy. Statistical analysis was performed using multivariate [partial least squares discriminant analysis (PLS-DA)] and univariate methods (linear mixed model). Multivariate data analysis (PLS-DA plots) of the liver metabolome revealed 3 different metabotypes (A = medium, B = minor, C = large alterations in liver metabolome profile between AP and PP status). Metabotype B animals were characterized by higher PP lipomobilization (stronger PP body condition decrease and higher blood bilirubin, fatty acids, gamma-glutamyltransferase, and triglyceride levels) and a higher occurrence of transition cow diseases, compared with the animals in metabotype C. Analysis of the feeding data showed that the period of metabotype B animals (calving in a distinct time frame) was characterized by a decreased grass silage quality. The PP liver metabolome of the metabotype C animals was characterized by higher concentrations of AA, acylcarnitines, lysoPC and sphingomyelins compared with metabotype B. For the metaphylactic treatment with BCC a dose-dependent effect was confirmed, differing between the metabotypes. In all matrices and metabotypes at various time points significant treatment effects were observed, with different profiles in clinical chemistry and as well in metabolomics data. The most clear-cut treatment effect was observed in metabotype B in the liver at 7 d PP, characterized by an increase in several acylcarnitines and phosphatidylcholines, indicating a more efficient influx and oxidation of fatty acids in mitochondria and thereby an increase in energy supply and more efficient triglyceride export in the liver. The results from the liver metabolomics analysis support the application of an indication-based metaphylactic treatment with BCC.


Asunto(s)
Lactancia , Metaboloma , Animales , Butilaminas , Bovinos , Dieta/veterinaria , Femenino , Hígado , Metabolómica , Leche , Ácidos Fosfínicos , Periodo Posparto , Embarazo , Estudios Prospectivos , Vitamina B 12
3.
J Dairy Sci ; 104(8): 9227-9244, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34024602

RESUMEN

The aims of this study were to evaluate histopathologic changes during the transition period, describe the histopathological features of the metabotypes identified in Part I (Schären et al., 2021b), and investigate effects of a metaphylactic treatment with butaphosphan and cyanocobalamin (BCC) on the liver parenchyma. Eighty German Holstein cows (mean 305-d production: 10,957 kg, range: 6,480-15,193 kg; mean lactation number: 3.9, range: 2-9) from a commercial dairy farm in Saxony, Germany, were enrolled in a randomized, prospective, triple-blinded study. Two groups received a treatment with BCC (5 or 10 mL/100 kg of body weight 10% butaphosphan and 0.005% cyanocobalamin, Catosal, Bayer Animal Health, n = 20 each) and one group a placebo treatment (NaCl 0.9%, n = 40). Liver biopsy specimens were collected 14 d antepartum (AP) and 7, 28, and 42 d postpartum (PP), routinely processed for histologic examination, and stained with hematoxylin and eosin, Sudan III, periodic acid-Schiff, and picrosirius red stains. The sections were assessed for fat and glycogen content and degenerative, inflammatory, fibrotic, and proliferative changes. The statistical analysis included the effects of the sampling day, the lactation number, the treatment, and the metabotype (A = medium, B = minor, C = large alterations in the liver metabolome profile between AP and PP status). There was mild to moderate fat infiltration in the liver of 37% of cows in the last 2 wk AP, and moderate to severe fat infiltration in 66% of cows in the first days PP. The degree of fat infiltration increased from 2 wk AP until the end of the first week PP, and then decreased until the end of the study period, at which time about 25% of cows had moderate to severe fatty infiltration. Lipidosis was positively correlated with the severity of liver cell degeneration, and negatively correlated with the degree of glycogen deposits. Complete glycogen depletion of hepatocytes was not observed in cows, even in the presence of severe hepatic lipidosis. Moderate to severe lymphocytic hepatitis was seen in 39% of cows throughout the study period, and cows with lactation numbers 5 or greater had perisinusoidal fibrosis more often than younger cows. Severe fibrosis and cirrhosis of the liver did not occur. Metabotype B animals exhibited a higher chance of fatty infiltration, lower glycogen storage, and perisinusoidal fibrosis and for this metabotype positive correlations were calculated between increased fat deposition in the liver and marked glycogen depletion, and increased degenerative, inflammatory, fibrotic, and proliferative changes of hepatic tissue. For the treatment with BCC, no significant effect was observed. In summary, during the transition period, the liver of dairy cows is characterized by fat accumulation and glycogen depletion and histologic signs of hepatitis and hepatocyte degeneration. These histomorphologic changes were accentuated in animals exhibiting little alterations in their liver metabolome profile across the transition period (metabotype B) and support the assumption of a decreased grass silage quality as a causative factor.


Asunto(s)
Lactancia , Periodo Posparto , Animales , Butilaminas , Bovinos , Dieta/veterinaria , Femenino , Alemania , Hígado , Metabolómica , Leche , Ácidos Fosfínicos , Estudios Prospectivos , Vitamina B 12
4.
Stem Cell Res ; 77: 103378, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38479332

RESUMEN

REEP1 is a transmembrane protein in the endoplasmic reticulum (ER) membrane that is involved in shaping and remodeling of the ER. Mutations in REEP1 cause SPG31, an autosomal dominant form of hereditary spastic paraplegia (HSP). Here we show the generation of a homozygous and a heterozygous REEP1 knockout induced pluripotent stem cell line suitable for in vitro disease modelling using the CRISPR/Cas9 editing system.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Heterocigoto , Homocigoto , Células Madre Pluripotentes Inducidas , Células Madre Pluripotentes Inducidas/metabolismo , Humanos , Línea Celular , Técnicas de Inactivación de Genes
5.
Sci Total Environ ; 942: 173757, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-38851329

RESUMEN

This study identified the occurrence of Holocene chronology hiatuses in the sedimentary record of the Patos-Mirim system caused by river avulsion processes, as well as evidence of sharp anthropogenic changes in the surrounding region of the lagoon water bodies. The presence of chronology hiatuses demonstrates the importance of considering the disturbance effect of paleo-drainage processes on the paleoenvironmental resolution and expression of the sedimentary record of such coastal plains. Anthropogenic activities especially those related to agriculture and forestry have increased significantly during the great acceleration, resulting in modifications of both the landscape and the environmental conditions of the lagoon bodies. Such impacts were clearly reflected in the sedimentary record where abrupt changes in palynological trends, sedimentary DNA, isotopic and granulometric analyses were inferred. The climatic conditions combined with regressive sea level can explain the chronology hiatuses. Pollen analyses demonstrated changes in the landscape, particularly indicated by the shift from Cyperaceae to Poaceae dominance after the 1960 CE. Therefore, all proxies together demonstrate the modification in the landscape and changes in the environment, clearly influenced by anthropogenic action from unsustainable agricultural practices.


Asunto(s)
Agricultura , Monitoreo del Ambiente , Sedimentos Geológicos , Ríos , Movimientos del Agua
6.
Front Pediatr ; 11: 1070465, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36969298

RESUMEN

Rhabdomyolysis is a challenging condition in pediatric emergency departments (PED): It ranges from asymptomatic illness with isolated elevation of creatine kinase (CK) levels to a life-threatening condition associated with extreme elevations in CK, electrolyte imbalances, circulatory failure (CF), acute kidney injury (AKI), and multi-organ disease. Most common causes of rhabdomyolysis are viral myositis and trauma, hereditary metabolic myopathies must be considered when facing rhabdomyolysis in early childhood. We report two cases of severe rhabdomyolysis with CF in our PED, thereby summarizing first-line management of rhabdomyolysis.

7.
Sci Total Environ ; 857(Pt 3): 159633, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36280064

RESUMEN

Microplastics (MPs) represent an emergent contamination marker. For this reason, we analyzed the vertical distribution of MPs in six sediment cores retrieved from the Patos-Mirim System, the world's largest coastal lagoonal system. The sediment cores span from mid Holocene to present times according to both radiocarbon and lead dating and are located close to both urban/industrial and agricultural regions. We identified a basal pre-disturbance MP-free zone in all cores and an uppermost contaminated 70-cm-zone, where a general increasing trend in MPs content resembling the human anthropization process was recorded. The predominant format of MPs was fiber, followed by fragments. The most commonly identified polymers were rayon, PVC, acrylate, polycarbonate and cellophane. Urban/industrial and agricultural activities were shown as clear sources of MPs, leading to comparable MPs concentration values in the sediment cores. Thus, MPs are collectively a reliable indicator of the Anthropocene onset, and in the Patos-Mirim System the most appropriate chronology can be assigned to the beginning of 1970s, matching the intensification of anthropogenic activities in the area.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Humanos , Plásticos , Sedimentos Geológicos , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Biomarcadores , América del Sur
8.
Nanotechnology ; 23(1): 015707, 2012 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-22155967

RESUMEN

We report on the electrical transport properties of single multiwall carbon nanotubes with and without an iron filling as a function of temperature and magnetic field. For the iron filled nanotubes the magnetoresistance shows a magnetic behavior induced by iron, which can be explained by taking into account a contribution of s-d hybridization. In particular, ferromagnetic-like hysteresis loops were observed up to 50 K for the iron filled multiwall carbon nanotubes. The magnetoresistance shows quantum interference phenomena such as universal conductance fluctuations and weak localization effects.


Asunto(s)
Hierro/química , Nanotubos de Carbono/química , Conductividad Eléctrica , Campos Magnéticos , Imanes/química , Nanotubos de Carbono/ultraestructura , Temperatura
9.
Clin Oral Implants Res ; 23(9): 1045-54, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22092339

RESUMEN

OBJECTIVES: The aim of this study was to follow patient cases retrospectively in a longitudinal manner from the time of implant placement to the time they were diagnosed with peri-implant disease, and to identify associated clinical and microbiological features of peri-implant disease. MATERIAL AND METHODS: A total of 281 patient cases were chosen from the archives of the Oral Microbiological Diagnostic Laboratory, Gothenburg, Sweden, based on bacterial samples taken from diseased implants. A form was designed and filled in separately for each case including data on patient, implant and disease profile. RESULTS: Most cases were severe peri-implantitis cases (91.4%). In 41.3% of the patients, peri-implantitis was developed early, already after having implants in function less than 4 years. The type of implant surface was significantly associated with the time in years implants were in function, before disease was developed (P < 0.05). The microbiological results by both culture and checkerboard analysis, although failed to fully correspond to the severity of the disease in terms of magnitude, proved to show that peri-implantitis is a polymicrobial anaerobic infection with increased number of AGNB (aerobic Gram-negative bacilli) in 18.6% of the patients. CONCLUSIONS: Peri-implantitis is a biological complication of implants in function that poses a threat to their long-term survival. It may develop earlier around implants with rough surfaces and it may represent a true infection. Microbiological sampling methods should be improved and uniformed so as to fully unveil the microbiological profile of the disease.


Asunto(s)
Implantación Dental Endoósea , Periimplantitis/microbiología , Periimplantitis/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Distribución de Chi-Cuadrado , Fracaso de la Restauración Dental , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Estadísticas no Paramétricas , Suecia
10.
Nanotechnology ; 21(43): 435501, 2010 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-20876975

RESUMEN

We present a novel ultrahigh stability sensor for quantitative magnetic force microscopy (MFM) based on an iron filled carbon nanotube. In contrast to the complex magnetic structure of conventional MFM probes, this sensor constitutes a nanomagnet with defined properties. The long iron nanowire can be regarded as an extended dipole of which only the monopole close to the sample surface is involved in the imaging process. We demonstrate its potential for high resolution imaging. Moreover, we present an easy routine to determine its monopole moment and prove that this calibration, unlike other approaches, is universally applicable. For the first time this enables straightforward quantitative MFM measurements.

11.
Nanotechnology ; 21(33): 335101, 2010 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-20657048

RESUMEN

Since the activity of several conventional anticancer drugs is restricted by resistance mechanisms and dose-limiting side-effects, the design of nanocarriers seems to be an efficient and promising approach for drug delivery. Their chemical and mechanical stability and their possible multifunctionality render tubular nanomaterials, such as carbon nanotubes (CNTs) and carbon nanofibres (CNFs), promising delivery agents for anticancer drugs. The goal of the present study was to investigate CNTs and CNFs in order to deliver carboplatin in vitro. No significant intrinsic toxicity of unloaded materials was found, confirming their biocompatibility. Carboplatin was loaded onto CNTs and CNFs, revealing a loading yield of 0.20 mg (CNT-CP) and 0.13 mg (CNF-CP) platinum per milligram of material. The platinum release depended on the carrier material. Whereas CNF-CP marginally released the drug, CNT-CP functioned as a drug depot, constantly releasing up to 68% within 14 days. The cytotoxicity of CNT-CP and CNF-CP in urological tumour cell lines was dependent on the drug release. CNT-CP was identified to be more effective than CNF-CP concerning the impairment of proliferation and clonogenic survival of tumour cells. Moreover, carboplatin, which was delivered by CNT-CP, exhibited a higher anticancer activity than free carboplatin.


Asunto(s)
Apoptosis/efectos de los fármacos , Carboplatino/farmacocinética , Proliferación Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Nanotubos de Carbono/química , Carboplatino/química , Carboplatino/farmacología , Línea Celular Tumoral , Preparaciones de Acción Retardada , Ensayos de Selección de Medicamentos Antitumorales , Estabilidad de Medicamentos , Humanos , Ensayo de Materiales , Nanofibras/química , Nanofibras/ultraestructura , Nanotubos de Carbono/ultraestructura , Neoplasias/tratamiento farmacológico , Ensayo de Tumor de Célula Madre
12.
Neurophysiol Clin ; 39(1): 27-30, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19268844

RESUMEN

INTRODUCTION: Pantothenate kinase-associated neurodegenerative disease (PKAN) is a secondary generalized dystonia associated with an accumulation of iron in the basal ganglia and increased motor cortex excitability. A pilot study in three patients with secondary generalized dystonia had reported a reduced frequency of painful axial spasms following inhibitory 1-Hz repetitive transcranial magnetic stimulation (rTMS) applied over the premotor cortex. PATIENT AND METHODS: We compared the effects of real versus sham rTMS on the frequency of the complex movement pattern and the need for additional benzodiazepine medication in a 6-year-old male patient with PKAN. A 20-minute session of left premotor 1-Hz rTMS was performed daily on 5 consecutive days. RESULTS: The occurrence of the complex movement pattern was gradually reduced from three to two attacks daily to one attack daily by real rTMS while sham rTMS had no effect. This reduction was obtained concomitantly with a similar reduction of additional benzodiazepines for both real and sham rTMS sessions. CONCLUSION: Inhibitory rTMS of the premotor cortex may be used to temporarily control motor symptoms in PKAN.


Asunto(s)
Corteza Motora/fisiología , Movimiento/fisiología , Enfermedades Neurodegenerativas/terapia , Fosfotransferasas (Aceptor de Grupo Alcohol)/deficiencia , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Estimulación Magnética Transcraneal , Benzodiazepinas/uso terapéutico , Encéfalo/patología , Niño , Discinesias/enzimología , Discinesias/genética , Discinesias/fisiopatología , Humanos , Intubación Gastrointestinal , Imagen por Resonancia Magnética , Masculino , Corteza Motora/patología , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/patología , Fármacos Neuromusculares/uso terapéutico , Resultado del Tratamiento
13.
J Chem Phys ; 128(22): 224701, 2008 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-18554037

RESUMEN

The influence of Li-doping on the mixed-valent vanadium oxide nanotubes has been investigated using electron energy loss spectroscopy. In particular, the electron diffraction profiles and the vanadium L excitation edges have been studied. We observe that the structure of the vanadium oxide nanotubes is stable against electron transfer upon Li-doping. Excitations at the vanadium L edges show features which are associated with a reduction of the vanadium valency.

14.
J Cancer Res Clin Oncol ; 116(5): 486-91, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2229139

RESUMEN

The aim of the study was to assess the value of routine bone scintigrams, independent of the primary tumor stage or the presence of symptoms, in the postsurgical follow-up of breast cancer patients for the early detection of bone metastases. For this purpose 1,000 patients with postsurgical breast cancer without previous documentation of metastatic disease, who were admitted to the special oncology hospital, Onkologische Klinik Bad Trissl, entered a prospective study in 1987-1988. The parameters followed were the TNM stage of the primary tumor, the presence of pain, bone pain as revealed by a thorough physical examination, and the patient's history for the assessment of risk factors. In addition, a whole-body skeletal scintigram, supplementary X-rays, and additional diagnostic measures were performed, if necessary, to detect bone metastases. It was shown that in 856 of 894 patients (groups 1-6) without clinical symptoms, the clinical examination and radiological and scintigraphic diagnostic measurements, demonstrating the absence of bone metastases, gave matching results, but in 12 of the 894 patients the results of all examinations remained questionable. In another 12 of the 894 patients (groups 1-3) radiological and/or scintigraphical evidence for the presence of bone metastases was found. In 14 of 79 cases (groups 7-10) with clinically suspicious symptoms these were proven to be signs of metastases by subsequent scintigrams, supplementary X-rays, and additional diagnostic measures. In 65 of the 79 patients with clinically suspicious symptoms, bone metastases could not be confirmed by obtaining bone scintigrams or X-rays while in the other 14 patients (groups 9 and 10) evidence for the presence of bone metastases was found in the scintigrams and/or X-rays. However, 10 of these 14 patients were high-risk patients for developing bone metastases as they had axillary lymph node infiltration. The other 4 patients were of the low-risk group as they had positive receptor status or no axillary lymph node infiltration at the time of primary diagnosis. In 13 of 27 patients (groups 11-14) with clinical symptoms indicating the presence of bone metastases this diagnosis was confirmed by scintigrams and/or X-rays (groups 11 and 12), while it was possible to exclude the presence of bone metastases in spite of the symptoms in 11 of the 27 patients. In the other 3 patients the results of the additional examinations remained questionable.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Neoplasias Óseas/diagnóstico , Neoplasias de la Mama , Neoplasias Óseas/secundario , Huesos/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Estadificación de Neoplasias , Estudios Prospectivos , Radiografía , Cintigrafía , Factores de Riesgo
15.
J Dent Res ; 74(9): 1607-12, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7560424

RESUMEN

A study was conducted to evaluate qualitative and quantitative differences in bacterial colonization on titanium, hydroxyapatite, and amalgam surfaces in vivo. Six healthy adult individuals participated in the study. Two pieces each of titanium, hydroxyapatite, and amalgam of similar size were placed in cobalt-chromium splints and kept intra-orally in each individual for 10 min, and 1, 3, 6, 24, and 72 hrs. After removal of the splints, the pieces were rinsed in PBS and transferred to transport medium. After being vortexed, the samples were inoculated on selective and non-selective media for analyses of various facultative and anaerobic bacteria. During the experiment, total viable count increased on all surfaces. The investigated bacterial groups constituted, on average, approximately 60 to 99% of the total viable count on all three types of surfaces in each of the experiments, except in the 10-minute samples, when they constituted around 20 to 30%. Various streptococcal species predominated and usually constituted > 50% of total viable count. Similar colonization patterns of Streptococcus spp., Actinomyces naeslundii, Neisseria spp., Hemophilus parainfluenzae, Fusobacterium spp., and black-pigmented Prevotella spp. were seen at all three types of surfaces. No significant differences among the materials regarding colonization of investigated bacteria were found during the study period. This study failed to show any qualitative and quantitative differences in bacterial colonization among these materials. Titanium, hydroxyapatite, and amalgam do not seem to have a marked influence on the early colonization pattern in vivo.


Asunto(s)
Bacterias Anaerobias/aislamiento & purificación , Adhesión Bacteriana/fisiología , Biopelículas/crecimiento & desarrollo , Materiales Dentales/efectos adversos , Placa Dental/microbiología , Adulto , Recuento de Colonia Microbiana , Amalgama Dental/efectos adversos , Depósitos Dentarios/microbiología , Placa Dental/etiología , Durapatita/efectos adversos , Glicoproteínas/metabolismo , Humanos , Persona de Mediana Edad , Unión Proteica , Saliva , Proteínas y Péptidos Salivales/metabolismo , Estadísticas no Paramétricas , Streptococcus/aislamiento & purificación , Propiedades de Superficie , Titanio/efectos adversos
16.
Eur J Gastroenterol Hepatol ; 13(10): 1161-7, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11711771

RESUMEN

OBJECTIVES: The overall incidence of common bile duct strictures due to chronic pancreatitis is reported to be approximately 10-30%. It remains a challenging problem for gastroenterologists and surgeons. The exact role of endoscopic stenting has not yet been clearly defined. DESIGN AND METHODS: Thirty-nine patients with chronic pancreatitis and symptomatic common bile duct stenoses underwent endoscopic stenting and were studied retrospectively. We were particularly interested in how many patients would achieve resolution of the stricture and tolerate removal of the stents in the long term. RESULTS: Indications for endoscopic stenting were symptomatic cholestasis, jaundice or cholangitis. The initial serum bilirubin was 8.3 mg/dl and the diameter of the common bile duct was 14.2 mm before stenting. Within 3-7 days of stenting, all patients presented improvement of jaundice and cholestasis. After a median stenting time of 9 months (range 1-144 months), 46% of the patients demonstrated regression of the stricture and clinical improvement, 26% required further stenting, and 28% were referred to surgery. Five patients received a self-expandable metal Wallstent. Thirty-one per cent demonstrated complete clinical recovery of the stricture as well as 10.2% a complete, radiologically verified stricture regression in a median follow-up of 58 months. CONCLUSIONS: There seems to be a therapeutic benefit for short-term endoscopic treatment but medium-term and long-term outcome remains questionable. Endoscopic stenting should be applied as an initial therapy before surgery, but it can be the definitive approach for older and morbid patients or cases with complete stricture regression after stent removal. Overall, it should not be considered as a routine procedure for symptomatic cases.


Asunto(s)
Colestasis Extrahepática/cirugía , Conducto Colédoco/cirugía , Endoscopía Gastrointestinal/métodos , Pancreatitis/complicaciones , Stents , Adulto , Anciano , Anciano de 80 o más Años , Colangiopancreatografia Retrógrada Endoscópica , Colestasis Extrahepática/diagnóstico por imagen , Colestasis Extrahepática/etiología , Enfermedad Crónica , Conducto Colédoco/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Reoperación , Estudios Retrospectivos , Resultado del Tratamiento
17.
Dalton Trans ; 42(14): 4897-902, 2013 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-23370695

RESUMEN

Single crystalline ammonium trivanadate NH4V3O8 with variable morphologies, including shuttles, flowers, belts, and plates, was synthesized by the hydrothermal treatment of NH4VO3 with acetic acid. The crystals optimally grow under gentle conditions of 140 °C for 48 h. The resulting NH4V3O8 microcrystals were characterized by means of X-ray diffraction, scanning electron microscopy, infrared and Raman spectroscopy, static magnetization studies, and thermal analysis. The key factors to control the size and morphology of the crystals are the pH value and the vanadium concentration. A tentative microscopic growth mechanism is proposed and it is demonstrated how shape and morphology of the resulting microcrystalline material can be tuned by appropriate synthesis parameters.

18.
Ultramicroscopy ; 111(8): 1360-5, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21864777

RESUMEN

An iron filled carbon nanotube (FeCNT), a 10-40 nm ferromagnetic nanowire enclosed in a protective carbon tube, is an attractive candidate for a magnetic force microscopy (MFM) probe as it provides a mechanically and chemically robust, nanoscale probe. We demonstrate the probe's capabilities with images of the magnetic field gradients close to the surface of a Py dot in both the multi-domain and vortex states. We show the FeCNT probe is accurately described by a single magnetic monopole located at its tip. Its effective magnetic charge is determined by the diameter of the iron wire and its saturation magnetization 4πM(s) ≈ 2.2 × 10(4)G. A magnetic monopole probe is advantageous as it enables quantitative measurements of the magnetic field gradient close to the sample surface. The lateral resolution is defined by the diameter of the iron wire and the probe-sample separation.

19.
Oral Microbiol Immunol ; 21(1): 6-11, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16390335

RESUMEN

BACKGROUND/AIMS: Various microbiological methods have been used for testing bacterial markers for periodontitis and periodontal disease progression. Most studies have used only a limited number of well recognized bacterial species. The purpose of the present study was to evaluate the association of 13 more recently identified bacterial species in a new panel in comparison with 12 previously more recognized periodontotopathogens ('old panel') using the 'checkerboard' DNA-DNA hybridization method. METHODS: Fifty individuals were chosen who showed at least one site with a probing pocket depth of 6 mm or more (disease) and bleeding on probing and at least one site with a probing pocket depth of 3 mm and without bleeding on probing (health). One diseased and one healthy site on each individual were sampled with the paperpoint technique and the samples were processed in the checkerboard technique against deoxigenin-labeled whole genomic probes to 25 subgingival species representing 12 well recognized and 13 newly identified periodontitis associated species. RESULTS: Twenty-four (out of 25) species were detected more frequently in the subgingival plaque of diseased than healthy sites both at score 1 (> 10(4)) and score 3 (> 10(5)). A significant difference at the higher score (score 3) was noticed for all species of the old panel except for three (Streptococcus intermedius, Selenomonas noxia, and Eikenella corrodens). Of the species in the new panel only Prevotella tannerae, Filifactor alocis, and Porphyromonas endodontalis showed a statistical significant difference between diseased and healthy sites. CONCLUSION: It was concluded that P. tannerae, F. alocis, and P. endodontalis should be added to the 12 species used for routine diagnostics of periodontitis-associated bacterial flora.


Asunto(s)
Sondas de ADN , ADN Bacteriano/análisis , Enfermedades Periodontales/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/análisis , ADN Bacteriano/genética , Placa Dental/microbiología , Eikenella corrodens/genética , Femenino , Fusobacterium/genética , Encía/microbiología , Hemorragia Gingival/microbiología , Humanos , Masculino , Persona de Mediana Edad , Hibridación de Ácido Nucleico/métodos , Bolsa Periodontal/microbiología , Periodontitis/microbiología , Prevotella/genética , Selenomonas/genética , Streptococcus intermedius/genética
20.
MMW Munch Med Wochenschr ; 118(10): 297-302, 1976 Mar 05.
Artículo en Alemán | MEDLINE | ID: mdl-177862

RESUMEN

Optimal after-care of mammary carcinoma begins with the end of the primary therapy and lasts practically for a lifetime. The after-care consists of several inpatient follow-ups in specially equipped follow-up clinics, of outpatient after-care by the general practitioner and of care by appointment at the treatment center. Standardized diagnostic methods combined with programmed appointments form the basis of an effective after-care for mammary carcinoma. The essence of a programmed and standardized after-care for mammary carcinoma lies in the fact that all participants are forced into a uniform and scheduled procedure by which the observance of a minimum program is guaranteed.


Asunto(s)
Cuidados Posteriores , Neoplasias de la Mama/terapia , Planificación de Atención al Paciente , Adulto , Femenino , Formularios Farmacéuticos como Asunto , Alemania Occidental , Humanos , Registros Médicos Orientados a Problemas , Persona de Mediana Edad , Metástasis de la Neoplasia , Neoplasias/diagnóstico , Aceptación de la Atención de Salud
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