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1.
Nat Mater ; 10(5): 352-6, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21499314

RESUMO

Fourier-transform infrared (FTIR) spectroscopy is a widely used analytical tool for chemical identification of inorganic, organic and biomedical materials, as well as for exploring conduction phenomena. Because of the diffraction limit, however, conventional FTIR cannot be applied for nanoscale imaging. Here we demonstrate a novel FTIR system that allows for infrared-spectroscopic nanoimaging of dielectric properties (nano-FTIR). Based on superfocusing of thermal radiation with an infrared antenna, detection of the scattered light, and strong signal enhancement employing an asymmetric FTIR spectrometer, we improve the spatial resolution of conventional infrared spectroscopy by more than two orders of magnitude. By mapping a semiconductor device, we demonstrate spectroscopic identification of silicon oxides and quantification of the free-carrier concentration in doped Si regions with a spatial resolution better than 100 nm. We envisage nano-FTIR becoming a powerful tool for chemical identification of nanomaterials, as well as for quantitative and contact-free measurement of the local free-carrier concentration and mobility in doped nanostructures.

2.
Environ Health Perspect ; 9: 313-5, 1974 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-4377876

RESUMO

Fibrous dusts (chrysotile, glass fibers, nemalite, palygorscite, and gypsum) and granular dusts (actinolite, biotite, hematite, pectolite, sanidine, and talcum) were injected intraperitoneally into rats. The fibrous dusts (other than gypsum) resulted in a high incidence of mesothelioma (30 - 67%). Gypsum produced only 5% and granular dusts none at all. It is suggested that the fibrous shape leads to a high multiplication rate of cells and predisposes to tumor formation. Fibrosis, in the other hand, does not so predispose. Milled chrysotile with 99.8% fibers than 5 mum in length are carcinogenic in our experience. The carcinogenicity of glass fibers in our experiments may have significance for occupational situations.


Assuntos
Neoplasias Abdominais/etiologia , Poeira , Mesotelioma/etiologia , Animais , Amianto/efeitos adversos , Cálcio/efeitos adversos , Vidro , Injeções Intraperitoneais , Ratos , Dióxido de Silício/efeitos adversos , Sulfatos , Talco/efeitos adversos
3.
J Cancer Res Clin Oncol ; 94(1): 87-109, 1979 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-224065

RESUMO

Five carcinomata of the nasopharynx (four lymphoepithelial carcinomata of the Regaud type and one squamous cell carcinoma) were examined light and electron microscopically. In addition to the familiar histological and cytological features of these tumors, and because of an increased antibody titer against Epstein-Barr virus in all five patients, all those cytoplasmic and nuclear inclusions were examined which could be interpreted as indicative of a virus contact. The following structures were found: 1. Particles and microtubules which correspond in diameter, shape, and location to Corona viruses. 2. Particles surrounded by a double membrane and resembling in form and diameter Oncorna viruses. 3. Tubulo-reticular, coil-shaped cytoplasmic inclusions interpreted as an unspecific reaction of the host cell to viral attack. 4. Spherical nuclear bodies, which are frequently observed in tumors and in viral infections. 5. Intranuclear particles which correspond in diameter, structure, and distribution to viruses of the herpes type such as have been described in cell cultures of Burkitt lymphoma and nasopharyngeal carcinoma. The fifth group particularly was discussed in detail with regard to differentiation between those particles and other structures which could simulate a virus structure. Together with the appearance of increased ribosomes and of particular chromatin distribution within the tumor cell nuclei, the particles we discussed have been interpreted as morphological indications of a virus etiology of the examined tumors.


Assuntos
Carcinoma de Células Escamosas/ultraestrutura , Corpos de Inclusão Viral/ultraestrutura , Neoplasias Nasofaríngeas/ultraestrutura , Carcinoma de Células Escamosas/etiologia , Núcleo Celular/ultraestrutura , Coronaviridae/ultraestrutura , Citoplasma/ultraestrutura , Herpesviridae/ultraestrutura , Herpesvirus Humano 4 , Humanos , Microscopia Eletrônica , Neoplasias Nasofaríngeas/etiologia , Viroses/complicações
4.
Lymphology ; 14(3): 101-12, 1981 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7289668

RESUMO

Radiological, light microscopic and electron microscopic findings after direct and indirect lymphography with Iotasul, a new non-ionic water-soluble (not oily) contrast medium, are reported. The results of the studies in 18 dogs clearly show that the roentgenological demonstration of the lymph system following intralymphatic administration of Iotasul in the dog is not inferior to that following the use of conventional oily con contrast medium passes quickly to the lymphatic system and the lymph nodes and is eliminated within 24 hours. The complications and tissue reactions known from oily contrast media are not observed following use of the new water-soluble contrast medium. Furthermore, studies of the fine structures show unequivocally that no morphologically detectable changes attributable to the contrast medium occur either in the region of the injection or in the lymph vessels, lymph nodes and organs such as kidney, liver, lung, spleen and myocardium. Preliminary studies indicate that the new contrast medium offers the possibility of indirect demonstration of lymph vessel regions and groups of lymph nodes (indirect lymphography) which have largely escaped detection by the previous routine lymphographic examination.


Assuntos
Meios de Contraste/administração & dosagem , Iodobenzoatos/administração & dosagem , Linfografia/métodos , Ácidos Tri-Iodobenzoicos/administração & dosagem , Animais , Cães , Feminino , Injeções Intradérmicas , Injeções Intralinfáticas , Soluções Isotônicas/administração & dosagem , Lactatos/administração & dosagem , Ácido Láctico , Linfonodos/patologia , Linfonodos/ultraestrutura , Sistema Linfático/patologia , Sistema Linfático/ultraestrutura , Masculino , Solução de Ringer
5.
Health Phys ; 58(5): 609-18, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-2341250

RESUMO

Bovine thyroid glands from different countries in Europe and human thyroid glands from Lower Saxony (Federal Republic of Germany) show isotopic 129I/127I ratios of 2.1 X 10(-9) to 8.2 X 10(-8) for cattle and 2.1 X 10(-9) to 8 X 10(-8) in humans. These values give information about the concentration of fallout 129I in Europe since most of these glands were collected in areas without nuclear facilities. Some of the human thyroids were collected after the Chernobyl accident between May 1986 and February 1988. Results obtained from human thyroids taken in some locations of Lower Saxony show no significant increase of the 129I during this time. Higher concentrations of 129I were only found in cattle grazing in the vicinity of a reprocessing plant in Mol, Belgium. Samples of soil, vegetation, milk, and water from this area contained higher than normal concentrations of 129I. The long-term transfer of radioiodine from the soil to the plant and the translocation within the soil were studied using a soil monolith with a 129I-contaminated surface. During the 4 y of the experiment, the transfer factor plant/soil decreased from 0.3 to 2.2 X 10(-3). Soil samples taken in 5-cm steps to a depth of 30 cm then at 40 and 50 cm depths showed that the transport of radioiodine to lower layers proceeds very slowly. The top 5-cm layer contained about 80% of the total radioactivity 52 mo after contamination. In an in-vivo study with a dairy cow, the transfer of radioiodine from feed to milk to cow meat and to pig thyroid gland was followed for 53 d using 129I-labeled pasture grass contaminated via roots. A part of the milk obtained from the cow was fed to a pig as a substitute for humans. The mean value of the transfer factor milk/feed was 2.4 X 10(-3) d kg-1. The values of the transfer factor cow meat/feed obtained for different muscle cuts and organs (excluding thyroid) ranged between 3.0 X 10(-4) (kidney) and 5.4 X 10(-2) d kg-1 f.w. The transfer factors pig thyroid/milk (as pig feed) and pig thyroid/cow feed exhibited values of 1.2 and 8.7 X 10(-3) d kg-1 f.w., respectively.


Assuntos
Contaminação Radioativa de Alimentos/análise , Radioisótopos do Iodo/análise , Glândula Tireoide/análise , Ração Animal/análise , Animais , Bovinos , Europa (Continente) , Humanos , Carne/análise , Leite/análise , Plantas/análise , Cinza Radioativa/análise , Poluentes Radioativos do Solo/análise , Suínos , Fatores de Tempo , Poluentes Radioativos da Água/análise
6.
Z Naturforsch C J Biosci ; 53(5-6): 325-30, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9679324

RESUMO

Acriflavine treatment on Streptomyces tendae generated a bald mutant (bld-1) with an altered antibiotic pattern. The parental strain produced nikkomycins and juglomycins, whereas the mutant bld-1 was only capable of juglomycin synthesis. The existence of a mutant defective in morphogenesis and in nikkomycin biosynthesis suggests a common regulation of these processes. An interesting finding of this study is that mutant bld-1 produced two carbazole derivatives, hitherto never seen in cultures of the parental strain. It seems likely that the DNA intercalating dye acriflavine, by mutagenesis, had activated cryptic genes which are involved in carbazole synthesis. The two carbazole derivatives were identified as the neuronal cell protecting compounds CS-79B and carquinostatin A, recently isolated from a wild-type of S. exfoliatus. We found that both substances showed antibacterial activity.


Assuntos
Aminoglicosídeos , Antibacterianos/biossíntese , Streptomyces/genética , Streptomyces/metabolismo , Acriflavina/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Carbazóis/química , Carbazóis/isolamento & purificação , Carbazóis/metabolismo , Carbazóis/farmacologia , Testes de Sensibilidade Microbiana , Morfogênese , Mutagênese , Naftoquinonas/metabolismo , Naftoquinonas/farmacologia , Fármacos Neuroprotetores , Streptomyces/efeitos dos fármacos
7.
Urologe A ; 17(2): 85-90, 1978 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-205028

RESUMO

Experience with and findings of a new method of indirect lymphography (endovesical lymphography) for roentgenologic visualization of lymph nodes and lymphatic vessels of the human urinary bladder are presented. After injection of Lipiodol Ultrafluid into the submucosal layer of the bladder wall all regional lymph node groups could be demonstrated. In cases of carcinoma of the bladder, endovesical lymphography provides early evidence of beginning carcinomatous infiltration of regional lymph nodes. Pedal lymphography as used thus far, provides information only about advanced lymphatic metastatic spread. It is possible that endovesical lymphography will yield new information leading to more accurate treatment of vesical carcinoma in terms of tumor staging.


Assuntos
Linfografia/métodos , Humanos , Óleo Iodado , Linfonodos/diagnóstico por imagem , Bexiga Urinária , Neoplasias da Bexiga Urinária/diagnóstico por imagem
8.
Nat Commun ; 3: 684, 2012 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-22353715

RESUMO

Light scattering at nanoparticles and molecules can be dramatically enhanced in the 'hot spots' of optical antennas, where the incident light is highly concentrated. Although this effect is widely applied in surface-enhanced optical sensing, spectroscopy and microscopy, the underlying electromagnetic mechanism of the signal enhancement is challenging to trace experimentally. Here we study elastically scattered light from an individual object located in the well-defined hot spot of single antennas, as a new approach to resolve the role of the antenna in the scattering process. We provide experimental evidence that the intensity elastically scattered off the object scales with the fourth power of the local field enhancement provided by the antenna, and that the underlying electromagnetic mechanism is identical to the one commonly accepted in surface-enhanced Raman scattering. We also measure the phase shift of the scattered light, which provides a novel and unambiguous fingerprint of surface-enhanced light scattering.

15.
Z Orthop Ihre Grenzgeb ; 118(5): 721-8, 1980 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-7467719

RESUMO

The existence of synovial differentiation at the lateral aspect of cervical discuss fissurations up to the development of joint-like spaces with synovial lining have been proved in all decades with the aid of a special investigation technique. A considerable individual variability as well as variable differentiations within the same cervical spine did not allow any correlation between the development of synovial spaces and pathological alterations or pathological load of the spine. The morphogenesis of the described synovial spaces has been discussed with respect to morphological and functional causal factors.


Assuntos
Disco Intervertebral/patologia , Adolescente , Adulto , Fatores Etários , Vértebras Cervicais/patologia , Feminino , Humanos , Deslocamento do Disco Intervertebral/etiologia , Masculino , Membrana Sinovial/patologia
16.
Klin Monbl Augenheilkd ; 175(5): 686-91, 1979 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-547096

RESUMO

The means of own observations the clinical picture of spontaneous hemorrhages into the conjunctival lymphatics is illustrated. The reasons of this phenomenon are discussed with regard to the histomorphological findings. Hitherto the spontaneous hemorrhages into the conjunctival lymphatics do not seem to have any pathogenic effect.


Assuntos
Túnica Conjuntiva , Hemorragia/etiologia , Linfangiectasia/etiologia , Adulto , Idoso , Feminino , Humanos , Sistema Linfático , Masculino , Pessoa de Meia-Idade
17.
Arch Otorhinolaryngol ; 223(2): 212-214, 1979.
Artigo em Alemão | MEDLINE | ID: mdl-32214605

RESUMO

Five carcinoma of the nasopharynx (four lymphoepithelial carcinoma of the Regaud type and one squamous cell carcinoma) were examined light and electron microscopically. In addition to the familiar histological and cytological features of these tumors, and because of an increased antibody titer against Epstein-Barr virus in all five patients, all those cytoplasmic and nuclear inclusions were examined which could be interpreted as indicative of a virus contact.The following structures were found:Particles and microtubules which correspond in diameter, shape and location to Corona viruses.Particles surrounded by a double membrane and resembling in form and diameter Onkorna viruses.Tubulo-reticular, coil-shaped cytoplasmic inclusions interpreted as an unspecific reaction of the host cell to viral attack.Spherical nuclear bodies, which are frequently observed in tumors and during viral infections.Intranuclear particles which correspond in diameter, structure and distribution to viruses of the herpes type such as have been described in cell cultures of Burkitt lymphoma and nasopharyngeal carcinoma. The fifth group particularly was discussed in detail with regard to differentiation between those particles and other structures which could simulate a virus structure.Together with the appearance of increased ribosomes and of particular chromatin distribution within the tumor cell nuclei, the particles we discussed have been interpreted as morphological indications of a virus etiology of the examined tumors.

18.
Arch Otorhinolaryngol ; 222(4): 295-317, 1979.
Artigo em Alemão | MEDLINE | ID: mdl-224851

RESUMO

Five cases of nasopharyngeal carcinoma with typically elevated EB-virus-antigen-titer were studied by light- and electron microscopic methods. Within the cytoplasm corona viruses in different forms, regular capsid-like particles with a diameter of 60 nm, tubuloreticular aggregates, and pathologic alterations of the membranes of the endoplasmatic reticulum could be found. The nuclei of the tumour cells often showed particles within the nucleoplasm with an average diameter of 100 nm containing a central core; the appearance of the particles is similar to that of herpes viruses as shown in the literature concerning EB-viruses. Atypic mitoses are common as well as free nucleoplasma-like condensates within the ground cytoplasm. Multiple doubling of the membranes of the endoplasmatic reticulum are characteristic for the tumor cell cytoplasm. Myelin figures are often situated within the enlarged tubules of the E. R., within mitochondria and within the nuclei. The results are discussed concerning the possible viral etiology of nasopharyngeal carcinoma. We do not believe that the particles found within the nucleoplasm have a relation to nuclear pores. The arguments are discussed.


Assuntos
Herpesvirus Humano 4/ultraestrutura , Neoplasias Nasofaríngeas/ultraestrutura , Antígenos Virais/análise , Coronaviridae/ultraestrutura , Herpesvirus Humano 4/imunologia , Humanos , Mitose
19.
Virchows Arch A Pathol Anat Histol ; 379(4): 285-98, 1978 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-212865

RESUMO

Light and electron microscopic investigations of four cases of juvenile nasopharyngeal fibroma revealed characteristic structures; a fibrous stroma, an inclination to hyalinisation and formation of scar like tissue, a lacunar thin walled vascular component, large numbers of mast cells and of fibroblasts. The tumor fibroblasts contained different nuclear bodies and particles. There existed five different types of more or less complex spherical bodies. The previously described nuclear electron dense particles with an electron lucent halo could be divided into four groups measuring 60, 90, 150, and 300 nm in diameter. In addition to the previously described ultrastructural properties of the tumors, the nuclei of the tumor fibroblasts were found to contain virus like particles. These particles were less electron dense, measuring 40 to 55 nm in diameter and arranged in groups throughout the nucleoplasm; they were different from chromatin condensations and from perichromatin granules. The structure and the size of the smallest particles was not comparable with the other nuclear inclusions.


Assuntos
Fibroma/ultraestrutura , Neoplasias Nasofaríngeas/ultraestrutura , Adolescente , Núcleo Celular/ultraestrutura , Criança , Fibroblastos/ultraestrutura , Humanos , Corpos de Inclusão/ultraestrutura , Masculino , Mastócitos/ultraestrutura , Microscopia Eletrônica
20.
Laryngol Rhinol Otol (Stuttg) ; 57(7): 602-11, 1978 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-210340

RESUMO

Light and electron microscopic investigations of four cases with juvenile nasopharyngeal fibroma revealed the characteristic structures like a fibrous stroma, and inclination to hyalinisation and formation of scar like tissue, a lacunar thin walled vascular component, a high amount of mast cells, and of fibroblasts with different nuclear bodies and particles. The well known electron dense nuclear inclusions were subdivided into three groups of size. The tumor cell nuclei also contained five different types of more or less complex bodies with spherical shape. In addition to the earlier described ultrastructural properties of the tumor the nuclei of the tumorous fibroblasts were found to contain virus like particles measuring 40 to 55 nm in diameter. These particles were aggregated to groups; they were different from chromatin condensations and from perichromatin granules. The structure and size of the smaller particles was not comparable to that of the electron dense nuclear inclusions regarded as pathognomonic in the nasopharynegal fibroma.


Assuntos
Fibroma/ultraestrutura , Neoplasias Nasofaríngeas/ultraestrutura , Adolescente , Criança , Feminino , Fibroma/patologia , Humanos , Corpos de Inclusão , Neoplasias Nasofaríngeas/patologia
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