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1.
Phys Rev Lett ; 124(6): 067202, 2020 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-32109129

RESUMEN

Understanding many-body physics of elementary excitations has advanced our control over material properties. Here, we study spin-flip excitations in NiO using Ni L_{3}-edge resonant inelastic x-ray scattering (RIXS) and present a strikingly different resonant energy behavior between single and double spin-flip excitations. Comparing our results with single-site full-multiplet ligand field theory calculations we find that the spectral weight of the double-magnon excitations originates primarily from the double spin-flip transition of the quadrupolar RIXS process within a single magnetic site. Quadrupolar spin-flip processes are among the least studied excitations, despite being important for multiferroic or spin-nematic materials due to their difficult detection. We identify intermediate state multiplets and intra-atomic core-valence exchange interactions as the key many-body factors determining the fate of such excitations. RIXS resonant energy dependence can act as a convincing proof of existence of nondipolar higher-ranked magnetic orders in systems for which, only theoretical predictions are available.

2.
Pharmazie ; 74(9): 563-565, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-31484598

RESUMEN

Rebuilding, stabilizing and maintaining the dermal lipid barrier is an encouraging disease management concept (relief and care) in the treatment and prevention of atopic dermatitis. Prevention and topical treatment, however, lack a simple, safe, effective and modular approach. For decades, the mainstay of topical therapy of atopic dermatitis has been corticosteroids, with innovations being rare. Our case report demonstrates the struggle of a patient with little relief of itchy dermal lesions and the recurrence of skin lesions following current therapeutic guidelines which proved to be ineffective. Therefore we decided to try an advanced C16-ceramide pathomechanism derived topical therapeutic measure since it offers hope of re-establishing skin and alleviating suffering. Amitriptyline in combination with linoleic acid offers a chance to release from dry and itchy skin, mild to moderate atopic dermatitis lesions without known serious adverse effects of topical corticosteroids, while preventing recurrence.


Asunto(s)
Amitriptilina/administración & dosificación , Ceramidas/metabolismo , Dermatitis Atópica/tratamiento farmacológico , Ácido Linoleico/administración & dosificación , Administración Cutánea , Niño , Dermatitis Atópica/patología , Fármacos Dermatológicos/administración & dosificación , Femenino , Humanos , Resultado del Tratamiento
3.
Basic Res Cardiol ; 108(2): 340, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23440385

RESUMEN

Hyaluronan (HA) is responsive to pro-atherosclerotic growth factors and cytokines and is thought to contribute to neointimal hyperplasia and atherosclerosis. However, the specific function of the pericellular HA matrix is likely depend on the respective stimuli. Adenosine plays an important role in the phenotypic regulation of vascular smooth muscle cells (VSMC) and is thought to inhibit inflammatory responses during atherosclerosis. The aim of this study was to examine the regulation and function of HA matrix in response to adenosine in human coronary artery SMC (HCASMC). The adenosine receptor agonist NECA (10 µM) caused a strong induction of HA synthase (HAS)1 at 6 h and a weaker induction again after 24 h. Use of selective adenosine receptor antagonists revealed that adenosine A2(B) receptors (A2(B)R) mediate the early HAS1 induction, whereas late HAS1 induction was mediated via A2(A)R and A3R. The strong response after 6 h was mediated in part via phosphoinositide-3 kinase- and mitogen-activated protein kinase pathways and was inhibited by Epac. Functionally, NECA increased cell migration, which was abolished by shRNA-mediated knock down of HAS1. In addition to HA secretion, NECA also stimulated the formation of pronounced pericellular HA matrix in HCASMC and increased the adhesion of monocytes. The adenosine-induced monocyte adhesion was sensitive to hyaluronidase. In conclusion, the current data suggest that adenosine via adenosine A2(B)R and A2(A)R/A3R induces HAS1. In turn a HA-rich matrix is formed by HCASMC which likely supports the migratory HCASMC phenotype and traps monocytes/macrophages in the interstitial matrix.


Asunto(s)
Adenosina/farmacología , Aterosclerosis/metabolismo , Vasos Coronarios/efectos de los fármacos , Ácido Hialurónico/metabolismo , Músculo Liso Vascular/efectos de los fármacos , Adenosina-5'-(N-etilcarboxamida)/farmacología , Adhesión Celular , Movimiento Celular , Proliferación Celular , Células Cultivadas , Vasos Coronarios/metabolismo , Cartilla de ADN/química , Regulación de la Expresión Génica , Glucuronosiltransferasa/genética , Glucuronosiltransferasa/metabolismo , Humanos , Hialuronano Sintasas , Monocitos/metabolismo , Músculo Liso Vascular/metabolismo , ARN Mensajero/efectos de los fármacos , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptor de Adenosina A3/metabolismo , Receptores de Adenosina A2/metabolismo , Receptores Purinérgicos/metabolismo , Transducción de Señal/fisiología , Vasodilatadores/farmacología
4.
Anaesthesiologie ; 71(11): 882-892, 2022 11.
Artículo en Alemán | MEDLINE | ID: mdl-35969253

RESUMEN

BACKGROUND: The transfusion of packed red blood cells (PRBC) is associated with various side effects, including storage damage to PRBCs. The cells change their structure, releasing potassium as well as lactate. Mechanical rinsing, available in many hospitals, is able to remove toxic substances and possibly minimizes the negative side effects of transfusion. OBJECTIVE: The primary aim of our study was to improve the quality of PRBCs before transfusion. The effects of different washing solutions on PRBC quality were analyzed. MATERIAL AND METHODS: This in vitro study compares 30 mechanically washed PRBCs. They were either processed with standard normal saline 0.9% (n = 15, N group) or a hemofiltration solution containing 4 mmol/l potassium (n = 15, HF group) by a mechanical rinsing device (Xtra, LivaNova, Munich, Germany). A subgroup analysis was performed based on the storage duration of the processed PRBCs (7, 14, 37 days). Samples were taken before washing (EKprä), immediately after washing (EKpost) and 10 h later (EKpost10h), after storage in the "wash medium" at room temperature. Concentrations of ATP (probability of survival in transfused erythrocytes), lactate, citrate and electrolytes (potassium, sodium, chloride, calcium) were tested. RESULTS AND CONCLUSION: Mechanical rinsing improves pretransfusion quality of PRBC. Washing with a hemofiltration solution results in a more physiological electrolyte composition. Even 10 h after mechanical rinsing with a hemofiltration solution, the quality of 37-day-old PRBC is comparable to young PRBC that have been stored for 7 days and have not been washed. Washing stored PRBC increases the ATP content, which subsequently leads to an increased probability of survival of red cells after transfusion.


Asunto(s)
Conservación de la Sangre , Eritrocitos , Conservación de la Sangre/métodos , Eritrocitos/química , Potasio/análisis , Electrólitos/análisis , Adenosina Trifosfato/análisis , Lactatos/análisis
5.
Artículo en Inglés | MEDLINE | ID: mdl-36502313

RESUMEN

INTRODUCTION: COVID-19 causes a considerable degradation of pulmonary function to the point of an acute respiratory distress syndrome (ARDS). Over the course of the disease the gas exchange capability of the lung can get impaired to such an extent that extracorporeal membrane oxygenation (ECMO) is needed as a life-saving intervention. In patients COVID-19 as well as ECMO may cause severe coagulopathies which manifest themselves in micro and macro thrombosis. Previous studies established D-dimers as a marker for critical thrombosis of the ECMO system while on admission increased D-dimers are associated with a higher mortality in COIVD-19 patients. It is therefore crucial to determine if COVID-19 poses an increased risk of early thrombosis of the vital ECMO system. METHODS: 40 patients who required ECMO support were enrolled in a retrospective analysis and assigned into 2 groups. The COVID group consist of 20 COVID-19 patients who required ECMO support (n = 20), whereas 20 ECMO patients without COVID-19 were assigned to the control group. D-dimers, fibrinogen, antithrombin III (AT III), lactate dehydrogenase (LDH) and platelet count were analysed using locally weighted scatterplot smoothing and MANOVAs. RESULTS: The analysis of both groups shows highly significant differences in the dynamics of hemostasis. The increase in D-dimers that is associated with thrombosis of the ECMO systems occurs in COVID-19 patients around 2 days earlier (p = 2,8115 10-11) while fibrinogen is consumed steadily. In the control group fibrinogen levels increase rapidly after ten days with a plateau phase of around five days (p = 1,407 10-3) . Both groups experience a rapid increase in AT III after start of support by ECMO (p = 5,96 10-15). In the COVID group platelet count decreased from 210 giga/l to 130 giga/l within eight days, while in the same time span in the control group platelets decreased from 180 giga/l to 105 giga/l (p = 1,1 10-15). In both groups a marked increase in LDH beyond 5000 U/l occurs (p = 3,0865 10-15). CONCLUSION: The early increase in D-dimers and decrease in fibrinogen suggests that COVID-19 patients bear an increased risk of early thrombosis of the ECMO system compared to other diseases treated with ECMO. Additionally, the control group shows signs of severe inflammation 10 days after the start of ECMO which were absent in COVID-19 patients.

6.
Clin Genet ; 79(1): 79-85, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21091464

RESUMEN

Submicroscopic chromosomal anomalies play an important role in the aetiology of intellectual disability (ID) and have been shown to account for up to 10% of non-syndromic forms. We present a family with two affected boys compatible with X-linked inheritance of a phenotype of severe neurodevelopmental disorder co-segregating with a deletion in Xp22.11 exclusively containing the PTCHD1 gene. Although the exact function of this gene is unknown to date, the structural overlap of its encoded patched domain-containing protein 1, the transmembrane protein involved in the sonic hedgehog pathway, and its expression in human cortex and cerebellum as well as in mice and drosophila brain suggests a causative role of its nullisomy in the developmental phenotype of our family. Our findings support the recent notions that PTCHD1 may play a role in X-linked intellectual disability (XLID) and autism disorders.


Asunto(s)
Cromosomas Humanos X , Genes Ligados a X , Discapacidad Intelectual , Receptores de Superficie Celular/genética , Trastorno Autístico/genética , Trastorno Autístico/fisiopatología , Niño , Humanos , Discapacidad Intelectual/genética , Discapacidad Intelectual/fisiopatología , Masculino , Receptores Patched , Linaje , Fenotipo , Eliminación de Secuencia , Adulto Joven
7.
Front Big Data ; 4: 577164, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34723175

RESUMEN

For the segmentation of magnetic resonance brain images into anatomical regions, numerous fully automated methods have been proposed and compared to reference segmentations obtained manually. However, systematic differences might exist between the resulting segmentations, depending on the segmentation method and underlying brain atlas. This potentially results in sensitivity differences to disease and can further complicate the comparison of individual patients to normative data. In this study, we aim to answer two research questions: 1) to what extent are methods interchangeable, as long as the same method is being used for computing normative volume distributions and patient-specific volumes? and 2) can different methods be used for computing normative volume distributions and assessing patient-specific volumes? To answer these questions, we compared volumes of six brain regions calculated by five state-of-the-art segmentation methods: Erasmus MC (EMC), FreeSurfer (FS), geodesic information flows (GIF), multi-atlas label propagation with expectation-maximization (MALP-EM), and model-based brain segmentation (MBS). We applied the methods on 988 non-demented (ND) subjects and computed the correlation (PCC-v) and absolute agreement (ICC-v) on the volumes. For most regions, the PCC-v was good ( > 0.75 ), indicating that volume differences between methods in ND subjects are mainly due to systematic differences. The ICC-v was generally lower, especially for the smaller regions, indicating that it is essential that the same method is used to generate normative and patient data. To evaluate the impact on single-subject analysis, we also applied the methods to 42 patients with Alzheimer's disease (AD). In the case where the normative distributions and the patient-specific volumes were calculated by the same method, the patient's distance to the normative distribution was assessed with the z-score. We determined the diagnostic value of this z-score, which showed to be consistent across methods. The absolute agreement on the AD patients' z-scores was high for regions of thalamus and putamen. This is encouraging as it indicates that the studied methods are interchangeable for these regions. For regions such as the hippocampus, amygdala, caudate nucleus and accumbens, and globus pallidus, not all method combinations showed a high ICC-z. Whether two methods are indeed interchangeable should be confirmed for the specific application and dataset of interest.

8.
Vox Sang ; 99(4): 348-53, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20624268

RESUMEN

BACKGROUND AND OBJECTIVES: Foetal alloimmune thrombocytopenia (FNAIT) is often treated transplacentally with maternally administered i.v. immunoglobulins, but not all foetuses show a consistent platelet increase during such treatment. MATERIALS AND METHODS: We retrospectively analysed data from a cohort of ten foetuses with FNAIT treated by direct foetal immunoglobulin infusion. Foetal treatment was begun between 17 and 25 weeks and continued until 36 weeks with weekly cordocenteses and foetal immunoglobulin infusions. RESULTS: While foetal IgG levels increased steadily during weekly IgG infusions, foetal platelet counts remained unchanged. CONCLUSION: Our retrospective study presents a unique analysis of a historical cohort, contributing to the ongoing debate about the treatment of choice for foetal alloimmune thrombocytopenia.


Asunto(s)
Plaquetas , Enfermedades Fetales/tratamiento farmacológico , Inmunoglobulina G/administración & dosificación , Inmunoglobulinas Intravenosas/administración & dosificación , Factores Inmunológicos/administración & dosificación , Trombocitopenia Neonatal Aloinmune/tratamiento farmacológico , Adulto , Femenino , Enfermedades Fetales/sangre , Terapias Fetales/métodos , Humanos , Recuento de Plaquetas , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Estudios Retrospectivos , Trombocitopenia Neonatal Aloinmune/sangre
9.
Vox Sang ; 98(3 Pt 2): 423-30, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19874573

RESUMEN

BACKGROUND AND OBJECTIVES: In fetal alloimmune thrombocytopenia (FAIT), transplacental maternal antibodies cause destruction of fetal platelets. FAIT is similar to fetal Rhesus haemolytic disease, but half of the affected fetuses are born to primiparous women. In 10-20% of cases, prenatal and perinatal intracranial haemorrhages are reported. Different therapeutic approaches have been described, including maternally administered high-dose intravenous immunoglobulin (high dose IVIG) without or with steroids or intrauterine transfusion (IUT) of compatible platelets. For the latter, the use of plasma-free maternal and donor platelets has been described, but a comparison of these two sources of platelets has not been reported. MATERIALS AND METHODS: We retrospectively analyzed the clinical courses of cases with FAIT treated with IUT of either HPA-matched donor platelets or maternal platelets, done by a single team between 1990 and 1997. In 57 pregnancies, FAIT was treated by repeated IUT with either maternal (15 fetuses) or donor platelets (42 fetuses). RESULTS: There was no procedure-related fetal or neonatal loss. Platelets from both sources reliably raised the fetal platelet counts. Donor platelet preparations contained more platelets and yielded higher fetal post-transfusion platelet counts, but maternal platelets were clinically equally effective. CONCLUSIONS: Donor and maternal platelet concentrates are effective sources for the treatment of FAIT.


Asunto(s)
Antígenos de Plaqueta Humana/inmunología , Enfermedades Fetales/terapia , Histocompatibilidad Materno-Fetal/inmunología , Transfusión de Plaquetas/métodos , Trombocitopenia Neonatal Aloinmune/terapia , Adulto , Donantes de Sangre , Transfusión de Sangre Intrauterina , Cesárea , Femenino , Enfermedades Fetales/inmunología , Edad Gestacional , Hematoma/etiología , Humanos , Recién Nacido , Isoanticuerpos/sangre , Masculino , Madres , Embarazo , Púrpura/etiología , Estudios Retrospectivos , Trombocitopenia Neonatal Aloinmune/inmunología
10.
Clin Hemorheol Microcirc ; 39(1-4): 417-22, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18503154

RESUMEN

INTRODUCTION: Biomarkers reflecting an inflammatory or immunological response are increasingly offered to improve the risk stratification of patients. For example, current evidence suggests that soluble CD40 ligand (sCD40L) is elevated in patients with acute coronary syndrome. But only a few data are available to evaluate the influence of preanalytic conditions on sCD40L values. METHODS: Blood samples of seven healthy blood donors were collected in tubes without additives and in EDTA- or citrate-filled tubes at various storage conditions. Platelet count was modified by serum dilution, and sCD40L was measured in platelet-rich-plasma and in whole blood. sCD40L levels were determined by an commercially available ELISA-Kit. RESULTS: Immediately after blood sample assessment, sCD40L levels in serum samples were elevated (1258+/-820 pg/ml) compared to EDTA (64+/-32 pg/ml) and citrate (60+/-8.5 pg/ml) values. Additionally, sCD40L levels were dependent on storage duration. After platelet activation, sCD40L levels were significantly increased to 8278+/-2453 pg/ml and were significantly correlated to platelet count (r=0.96). CONCLUSIONS: Soluble CD40L levels were clearly influenced by preanalytical conditions and were dependent on storage duration, sample technique and platelet count. These influences should be considered by the determination and evaluation of sCD40L concentrations.


Asunto(s)
Ligando de CD40/sangre , Adulto , Biomarcadores , Plaquetas/metabolismo , Ácido Cítrico/química , Ácido Edético/química , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Humanos , Sistema Inmunológico , Inflamación , Masculino , Recuento de Plaquetas , Solubilidad , Factores de Tiempo
11.
Hamostaseologie ; 28(1-2): 66-71, 2008 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-18278165

RESUMEN

Based on the concept that the so-called resistance to anti-platelet drugs is meant to describe a phenomenon where the drug does not hit its direct pharmacodynamic target, assays, used to evaluated the effects of anti-platelet drugs, should as closely as possible measure the direct pharmacodynamic effect of a particular drug. Thus, for the detection of aspirin effects, thromboxane concentrations or arachidonic acid-induced responses (light aggregometry, whole-blood aggregometry) should be measured. For the detection of clopidogrel actions, VASP phosphorylation (flow cytometry) or ADP-induced responses (light aggregometry, whole blood aggregometry) should be analysed.


Asunto(s)
Aspirina/uso terapéutico , Resistencia a Medicamentos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Agregación Plaquetaria/efectos de los fármacos , Ticlopidina/análogos & derivados , Clopidogrel , Humanos , Ticlopidina/uso terapéutico
12.
Bone Joint J ; 100-B(9): 1175-1181, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30168756

RESUMEN

Aims: The traditional transosseus flexor hallucis longus (FHL) tendon transfer for patients with Achilles tendinopathy requires two incisions to harvest a long tendon graft. The use of a bio-tenodesis screw enables a short graft to be used and is less invasive, but lacks supporting evidence about its biomechanical behaviour. We aimed, in this study, to compare the strength of the traditional transosseus tendon-to-tendon fixation with tendon-to-bone fixation using a tenodesis screw, in cyclical loading and ultimate load testing. Materials and Methods: Tendon grafts were undertaken in 24 paired lower-leg specimens and randomly assigned in two groups using fixation with a transosseus suture (suture group) or a tenodesis screw (screw group). The biomechanical behaviour was evaluated using cyclical and ultimate loading tests. The Student's t-test was performed to assess statistically significant differences in bone mineral density (BMD), displacement, the slope of the load-displacement curves, and load to failure. Results: The screw group showed less displacement (loosening) during cyclical loading, which was significant during 300, 500, 600, 700, 800, 900, and 1000 cycles (p < 0.05: other cycles: 0.079 < p < 0.402). Compared with the suture group, the screw group had higher mean ultimate load values (133.6 N, sd 73.5 vs 110.1 N, sd 46.2; p = 0.416). Conclusion: Fixation of the FHL tendon with a tenodesis screw enables a less invasive procedure to be undertaken and shows similar biomechanical behaviour and primary strength compared with fixation using a transosseus suture. Cite this article: Bone Joint J 2018;100-B:1175-81.


Asunto(s)
Tendinopatía/cirugía , Transferencia Tendinosa/métodos , Tenodesis/métodos , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Densidad Ósea , Tornillos Óseos/efectos adversos , Cadáver , Femenino , Humanos , Masculino , Persona de Mediana Edad , Suturas/efectos adversos , Transferencia Tendinosa/efectos adversos , Tendones/cirugía , Tendones/trasplante , Tenodesis/efectos adversos
13.
Phys Med Biol ; 63(14): 14NT01, 2018 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-29897342

RESUMEN

As quantitative susceptibility mapping (QSM) is maturing, more clinical applications are being explored. With this comes the question whether QSM is sufficiently robust and reproducible to be directly used in a clinical setting where patients are possibly not cooperative and/or unable to suppress involuntary movements sufficiently. Twenty-nine patients with Alzheimer's disease, 31 patients with mild cognitive impairment and 41 healthy controls were scanned on a 3 T scanner, including a multi-echo gradient-echo sequence for QSM and an inversion-prepared segmented gradient-echo sequence (T1-TFE, MPRAGE). The severity of motion artifacts (excessive/strong/noticeable/invisible) was categorized via visual inspection by two independent raters. Quantitative susceptibility was reconstructed using 'joint background-field removal and segmentation-enhanced dipole inversion', based on segmented subcortical gray-matter regions, as well as using 'morphology enabled dipole inversion'. Statistical analysis of the susceptibility maps was performed per region. A large fraction of the data showed motion artifacts, visible in both magnitude images and susceptibility maps. No statistically significant susceptibility differences were found between groups including motion-affected data. Considering only subjects without visible motion, significant susceptibility differences were observed in caudate nucleus as well as in putamen. Motion-effects can obscure statistically significant differences in QSM between patients and controls. Additional measures to restrict and/or compensate for subject motion should be taken for QSM in standard clinical settings to avoid risk of false findings.


Asunto(s)
Enfermedad de Alzheimer/patología , Artefactos , Mapeo Encefálico/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Movimiento , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad
14.
Ophthalmologe ; 114(8): 759-766, 2017 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-28699050

RESUMEN

Optic nerve hypoplasia (ONH) is one of the most common causes of congenital visual impairment. It was first described in 1915 and represents a developmental disorder of the central nervous system. It is often associated with intracranial midline defects and is then referred to as septo-optic dysplasia (SOD). The symptoms of ONH range from minimal visual dysfunction to significant visual impairment with sensory defect nystagmus and even blindness. The ONH is often associated with further systemic, endocrinological and neurological abnormalities requiring a close interdisciplinary treatment of the patients.


Asunto(s)
Sistema Nervioso Central/anomalías , Enfermedades del Nervio Óptico/diagnóstico , Nervio Óptico/anomalías , Displasia Septo-Óptica/diagnóstico , Esotropía/diagnóstico , Esotropía/terapia , Hormona de Crecimiento Humana/deficiencia , Humanos , Enfermedades Hipotalámicas/diagnóstico , Enfermedades Hipotalámicas/terapia , Oftalmoscopios , Oftalmoscopía , Enfermedades del Nervio Óptico/terapia , Enfermedades de la Hipófisis/diagnóstico , Enfermedades de la Hipófisis/terapia , Displasia Septo-Óptica/terapia
16.
Arch Intern Med ; 139(2): 148-53, 1979 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-434967

RESUMEN

Using venography as the reference procedure, this study examined the utility of fibrinogen I 125 scanning for the detection or demonstration of deep venous thrombosis. The results demonstrate the inability of leg scanning to detect accurately the presence or absence of thrombi in the deep venous system. Most striking was the lack of sensitivity of this procedure in areas where the propensity for embolization is greatest. Sensitivity is extremely low in the anatomic areas where leg scanning demonstrates reasonable specificity. The results are nearly identical in the extremity not operated upon. The validity of all prior studies relying heavily or exclusively on 125I leg scans to determine the presence or absence of thrombi must be critically reassessed.


Asunto(s)
Fibrinógeno , Pierna/diagnóstico por imagen , Tromboflebitis/diagnóstico por imagen , Humanos , Radioisótopos de Yodo , Pierna/irrigación sanguínea , Flebografía , Cintigrafía
17.
Biomed Tech (Berl) ; 50(1-2): 14-8, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15792196

RESUMEN

Electromagnetic hypersensitivity (EH) is an increasing problem in modern industrial societies. As crawling sensations are frequently mentioned by EH patients alterations in cutaneous microcirculation possibly linked to exposure to magnetic fields might be involved in the development of such sensations and further dysesthesias. In seven healthy volunteers and in three persons convinced to suffer from EH the microcirculation of the right thumb was determined by laser-Doppler-flowmetry (LDF) during exposure to circularly polarized 50 Hz magnetic flux densities of 96 mT. During field exposure the LDF values remained constant. The LDF ratio "field on/field off" was found to be 1.03 +/- 0.03. In contrast, reactive hyperemia and hyperventilation caused significant changes in the LDF values of volunteers as well as of EH patients. Following arterial congestion of the forearm microcirculation of the thumb was clearly increased during reperfusion, and the LDF values were elevated up to 2.02 +/- 0.36. 10 deep breaths caused a significant decrease in the LDF values up to 0.63 +/- 0.18. In conclusion, reactive hyperemia and hyperventilation caused clear alterations of cutaneous microcirculation, whereas, 50 Hz magnetic fields had no influence on cutaneous microcirculation.


Asunto(s)
Velocidad del Flujo Sanguíneo/efectos de la radiación , Campos Electromagnéticos/efectos adversos , Microcirculación/efectos de la radiación , Traumatismos por Radiación/etiología , Traumatismos por Radiación/fisiopatología , Piel/irrigación sanguínea , Piel/efectos de la radiación , Adulto , Electricidad/efectos adversos , Exposición a Riesgos Ambientales/efectos adversos , Femenino , Humanos , Masculino , Dosis de Radiación , Medición de Riesgo/métodos , Factores de Riesgo
18.
Chest ; 67(3): 293-7, 1975 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-46192

RESUMEN

Mycotoxicosis is a term used to define a toxic reaction due to the ingestion of toxins produced by fungi. Oral ingestion, however, may not be the sole means of exposure. We have recently observed ten patients who had inhaled massive amounts of fungi, which resulted in an apparent toxic pulmonary reaction. Immunologic studies showed no sensitivity to various fungal antigen preparations and histologic study of the lung showed a multi-focal acute process, with primary involvement of the terminal bronchioles containing large numbers of various spores. Cultures from lung biopsy material revealed at least five fungal organisms. A one to ten year followup indicates that avoidance of massive reexposure to fungal dust is the key to the prevention of recurrent pulmonary mycotoxicosis.


Asunto(s)
Enfermedades de los Trabajadores Agrícolas/diagnóstico , Enfermedades Pulmonares Fúngicas/diagnóstico , Micotoxinas , Adolescente , Adulto , Biopsia , Células Cultivadas , Diagnóstico Diferencial , Exposición a Riesgos Ambientales , Femenino , Estudios de Seguimiento , Hongos/aislamiento & purificación , Humanos , Pulmón/microbiología , Enfermedades Pulmonares Fúngicas/diagnóstico por imagen , Enfermedades Pulmonares Fúngicas/inmunología , Enfermedades Pulmonares Fúngicas/microbiología , Masculino , Persona de Mediana Edad , Fibrosis Pulmonar/diagnóstico , Radiografía , Coloración y Etiquetado
19.
Chest ; 67(5): 608-10, 1975 May.
Artículo en Inglés | MEDLINE | ID: mdl-1126203

RESUMEN

Distal propulsion of a 28 mm umbrella filter from vena cava to femoral vein occurred in a 75-year-old woman during external cardiac massage. After cardiac massage, filter position must be checked roentgenographically. Optimal management of distal migration might include placement of a second umbrella to prevent recurrent emboli and proximal migration of the dislodged umbrella.


Asunto(s)
Vena Femoral , Filtración , Masaje Cardíaco/efectos adversos , Embolia Pulmonar/prevención & control , Vena Cava Inferior , Anciano , Femenino , Vena Femoral/diagnóstico por imagen , Humanos , Radiografía , Recurrencia , Vena Cava Inferior/diagnóstico por imagen
20.
Chest ; 69(6): 790-2, 1976 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1277902

RESUMEN

The antemortem diagnosis of myocardial sarcoidosis is rare in patients without overt signs of the disease. Two patients are presented to alert physicians to the value of early scalene node biopsy when sarcoidosis could be the cause of marked disturbances in cardiac conduction. The first patient, aged 29 years, had first, second, and third degree atrioventricular block and intermittent left and right bundle-branch block; the second, aged 59 years, had second degree atrioventricular block and complete right bundle-branch block. Both had diagnoses of sarcoidosis based on scalene node biopsy. The cardiac conductive disturbance improved, and the symptoms disappeared with steroid therapy.


Asunto(s)
Cardiomiopatías/diagnóstico , Ganglios Linfáticos/patología , Sarcoidosis/diagnóstico , Adulto , Biopsia , Electrocardiografía , Femenino , Sistema de Conducción Cardíaco/fisiopatología , Humanos , Cuello
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