Resolving the electromagnetic mechanism of surface-enhanced light scattering at single hot spots.

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.

Infrared-spectroscopic nanoimaging with a thermal source.

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.

Carbazole antibiotics synthesis in a Streptomyces tendae bald mutant, created by acriflavine treatment.

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.

[Metastatic bile duct cancer in secondary biliary cirrhosis associated with primary sclerosing cholangitis in ulcerative colitis]. / Metastasierendes Gallengangskarzinom bei sekundär biliärer Zirrhose auf dem Boden einer primär sklerosierenden Cholangitis bei Colitis ulcerosa.

By means of a case-report of a 33 years old pat., having colitis ulcerosa for 16 years with serious epitheldysplasia and developing primary sclerosing cholangitis, the typical progress of the disease with manifestation of a secondary biliary cirrhosis is shown. The course was complicated by the development of a bile-duct carcinoma. Present possibilities of diagnosis and therapy are discussed.

Measurements of 129I in human and bovine thyroids in Europe--transfer of 129I into the food chain.

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.

[Metastasizing malignant melanoma of the vagina]. / Metastasierendes malignes Melanom der Vagina.

We report on a 54-year-old patient with multiple cutaneous, lung and liver metastases. The primary tumour is a malignant melanoma of the vagina, who developed within one year after the last gynaecological examination. Our case report is another example for the poor prognosis of this rare vaginal tumour.

Carcinogenicity studies on natural and man-made fibres with the intraperitoneal test in rats.

Female Wistar rats were injected intraperitoneally (i.p.) with a suspension of 11 fibrous and 3 granular dusts. A dose of 0.25 mg actinolite or UICC chrysotile induced tumours of the peritoneum in more than 50% of the animals. Even 0.05 and 0.01 mg proved to be carcinogenic, although no adhesions of the abdominal organs could be observed. The findings are in conflict with the hypothesis that a scar is always the morphological precondition for the development of an asbestos-induced tumour. Actinolite injected i.p. in a solution of polyvinylpyridine-N-oxide gave a lower tumour incidence than when suspended only in saline, possibly due to inactivation of the fibre surface. Persistent glass fibres were less effective than actinolite having a similar fibre size distribution. On the other hand, relatively thick basalt fibres and ceramic fibres gave higher tumour incidences than expected. Wollastonite fibres were not carcinogenic, probably because of their low durability. Large amounts of polyvinylchloride, alpha-ferric oxide hydrate and wood dust also led only to adhesions of the abdominal organs and fibrosis; a definite carcinogenic effect was not detected.

Carcinogenicity studies on fibres, metal compounds, and some other dusts in rats.

About 50 dusts were examined on their carcinogenicity in rats mainly after intraperitoneal injection and some after intratracheal instillation. In the i.p. test, very low doses between 0.05 and 0.5 mg asbestos led to tumour incidences of about 20 to 80%. Polyvinyl-pyridine-N-oxide prolonged the tumour latency after injection of actinolite. 60 mg attapulgite from three sources with short fibre lengths were not shown to be carcinogenic but an attapulgite sample with longer fibres had a moderate effect. Relatively thick rock and ceramic fibres (median greater than 1 micron) induced tumours, but slag and wollastonite fibres did not, probably because of their better solubility. Intratracheal instillations of glass microfibres (20 X 0.5 mg) led to lung tumours in 5 of 34 rats (0 in control). The carcinogenic potency of an inorganic fibre depends on its size and persistency, and possibly also on other properties, especially on the surface. Nickel powder, nickel oxide, nickel subsulfide and cadmium sulfide were all found to be carcinogenic in the two tests. Cadmium chloride and cadmium oxide could only be administered in very low doses because of their high acute toxicity. A high amount of magnetite (15 X 15 mg i.tr.) led to an unexpected lung tumour incidence of 69%. The i.p. test in rats proved to be very sensitive for detecting the carcinogenic potency of non-acute toxic natural and man-made mineral dusts as well as metal compounds. This means that, if a high dose of one of these dusts does not induce tumours in this test, no suspicion of carcinogenic potency can be substantiated.

[Synovitis in familial Mediterranean fever]. / Die Synovitis des familiären Mittelmeerfiebers.

Arthroscopy done on a 24-year-old turkish male with familial Mediterranean fever (FMF) and arthritis of the knee joint provided morphological data during the acute stage of FMF-arthritis. Main finding is a heavy granulocytic infiltration of the subsynovial stratum, similar to that seen in non-specific purulent inflammation, accompanied by marked ectasis and hyperaemia of the synovial vessels. In the microbiologically sterile synovial fluid cell counts and lactate values are found as in bacterial arthritis. The typical history and the characteristic course of the disease are indicators for the diagnosis. Serological, immunological and radiological findings are non-specific. The efficacy of prophylactic colchicine in symptomatic therapy could be verified but it is essential that the drug is taken regularly and that the patient is instructed accordingly. Investigation of other members of the family showed a high frequency of intermarriages and the presence of this autosomal-recessive inherited disease in three generations.

Iotasul, a water-soluble (non-oily) contrast medium for direct and indirect lymphography: radiological and morphological investigations in dogs.

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.

[Morphological evidence of synovial spaces in the uncovertebral region of cervical discs (author's transl)]. / Morphologischer Nachweis synovialer Spalträume in der Unco-Vertebral-Region zervikaler Bandscheiben.

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.

[Studies on the tumourigenicity of extracts and their fractions of airborne particulates with the subcutaneous test in the mouse (author's transl)]. / Untersuchungen zur tumorerzeugenden Wirkung von Extrakten und Extraktfraktionen aus atmosphärischen Schwebstoffen im Subkutantest bei der Maus.

Airborne particulate matter was collected on filters at various times in Duisburg, Duesseldorf, Muenster and in 2 rural areas. After extraction with organic solvents the extract was partly fractionated and analyzed for BaP and 7 other polycyclic aromatic hydrocarbons (PAH). The carcinogenicity was examined with the subcutaneous test using 7000 mice in total. The amount of extract required was relatively small. Extracts from suspended matter with a BaP content of 0.37 to 1.1 microgram BaP brought about tumour rates in the range of 30%. On account of the results the following can be concluded: 1. The total extract of atmospheric particulates results in definite dose-response relationship, when the part of the compounds not belonging to the PAH is rather low. 2. The PAH fractions derived from the suspended matter collected in different cities show the same carcinogenic potency, when they are adjusted to the same BaP level by means of concentration or dilution. 3. The PAH bear the most important share with respect to the carcinogenic potency of an extract from suspended matter. 4. Numerous compounds (polar substances) which are not classed with the PAH are carcinogenic to some extent, partly they are able to inhibit the carcinogenic effect. 5. The dose-response relationship of BaP is strongly leveled off in general when all the substances of an extract are present. That means when the dose of an extract is low, the importance of BaP becomes less. Therefore a fixed ratio concerning the effect of BaP within an extract cannot be given. It has to be examined in particular, which PAH and non-PAH are necessary to analyse in order to describe the carcinogenic effect due to an extract from airborne particulates. Much more attention is to be payed to the polar substances.

Tumour induction after intraperitoneal injection of fibrous dusts.

I.p. injection of glass fibres to rats of different strains resulted partly in different tumour rates. Young rats showed more marked coalescence and earlier growth of tumours but also earlier mortality without tumours, as compared with older rats. Haemorrhagic ascites from tumour-bearing rats induced tumours after i.p. injection. Tumours were also obtained after i.p. injection of fibres in European hamsters and rabbits, but these species are less susceptible than rats. Histological studies in rats show that fibrosis is not an absolute requirement for the development of a fibre-induced mesothelioma. After intratracheal instillation of either crocidolite or glass fibres in European hamsters, the respective fibres showed up in the diaphragm and in the spleen.

[Comparative morphology of lymphoepithelial carcinoma in primary tumor, metastasis, and xenograft (author's transl)]. / Vergleichende Morphologie des lymphoepithelialen Karzinoms Primärtumor--Metastase--Xenotransplantat.

Tissue of lymphoepithelial tumor metastasis was transplanted subcutaneously to thymus-aplastic "nude" mice. After 75 days a pea-size tumor was developing which again was transplanted to further murine passages. During the second passage the tumor was growing faster and material was taken for light and electron microscopy. The results were compared with the datas obtained from the primary nasopharyngeal carcinoma and metastasis. The tumor cells of the metastasis and of the xenograft showed all morphological criteria of a non-keratinizing squamous epithelial carcinoma of undifferentiated type. The ultrastructural criteria of the human NPC-tumor cells were all present including cytoplasmic deposits of Corona viruses and Herpes virus-like particles within the nuclei and the cytoplasm.

[Induction of partial immune tolerance in a closely-related species system by a single injection of papain-extracted, donor species specific, lymphocyte membrane antigens]. / Induktion partieller Immunotoleranz im nah verwandten Speziessystem durch einmalige Injektion eines mit Papain gewonnenen, spenderspezies-spezifischen Lylmphozytenmembran-Antigens.

This paper reports of experimental xenografting of kidneys in closely related species (fox-dog) modifying primary graft rejection by single i.v. injection of donorspecies-specific lymphocyte antigen in soluble form. Papain treatment was used to separate histocompatibility antigens from lymphocytes of donors. This antigen, in vitro, is capable of reducing cytotoxicity of xeno-antisera by adsorption of their lymphocytotoxic antibodies. A single intraoperative i.v. injection of this antigen to the transplant recipients results in the subsequent failure of humoral antibody production, thus this antigen-mediated effect is thought to be a state of B-cell tolerance. Survival times are more than doubled in comparison to untreated controls and last in average 14.6 +/- 1.74 days (n = 5). Histological studies demonstrate rather well conserved renal parenchym with sporadic infiltrations of round cells.

[Morphometric studies on lymphatic vessels of the axillary region]. / Morphometrische Untersuchungen an Lymphgefässen des Axillarbereiches.

Axillary lymph vessels of 94 autopsy cases (42 female, 52 male) have been investigated histologically in serial slices. Total diameter of the lymph vessels, vascular wall diameter, diameter of the medial connective tissue, finally that one of the artificial tissue spaces were measured in almost 8000 single measurements. The mean values of counts for the different vascular wall components were assessed statistically with the aid of a computer. By reason of the enormous individual variation of the number and the size in lymph vessel system a direct comparison of the measurement data from the different wall components was impossible. Therefore, the ratio of connective tissue to smooth muscle within the vascular media was regarded as a significant parameter for the development of a lymphangiosclerosis. The connective tissue/smooth muscle gradient increased from decade to decade with a slighter progression in groups with higher age A significant increase of lymphangi osclerosis was noted in cases with right heart insufficiency in correlation to the degree of heart insuffiency. Severe lymphangiosclerotic alterations were developed after radical mastectomy and radiotherapy of the axilla, after radiotherapy of other malignant tumors, and in cases with heart failures or vascular dysplasia. Morphometric investigations were not possible in cases with floride lymphangitis and in one case of general vascular amyloidosis.

[Spontaneous hemorrhages into dilated conjunctival lymphatics (author's transl)]. / Spontane Blutfüllung ektatischer Bindehautlymphgefässe.

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.

[Experimental study on erysipeloid arthritis in the rabbit after blockage of lymph drainage]. / Experimentelle Untersuchungen zur Rotlauf-Arthritis beim Kaninchen nach zusätzlicher Lymphabflussblockade.

The lymph drainage was radically blocked in 29 rabbits. One to three days after the operation Erysipelothrix rhusiopathiae was inoculated subcutaneously into the animals. Some control animals were injected with agents of erysipelas and some only with the sterile solution without additional blockade of the lymph drainage. Light and electron microscopy as well as immuno-histological tests showed that the erysipelas arthritis developing in rabbits closely resembles human rheumatoid arthritis with exsudative-necrotising changes of the synovial membrane, proliferation of synovial cells and subsynovial, perivascular plasmacell, and lymphocyte infiltration. The changes were not intensified by the additional blockade of the lymph drainage, when comparing the side with lymph drainage blockade and the non-operated side. The results may be explained by a marked pathogenetic importance of the erysipelas infection in comparison to the relatively mild, lymphostate dependent alterations as well as by mobilisation of macrophages on the operated side.

["Plica disease" (synovial folds) of the knee-joint: arthroscopic and histological findings, with suggestions for treatment (author's transl)]. / Die "Plica-Krankheit" dem Kniegelenks, Arthroskopische und histologische Refunde mit Ablteitung von Therapievorschlägen.

A mediopatellar plica (synovial fold) of the knee-joint may develop without recognisable cause in adolescents or young adults, predominantly females. It leads to pain on pressure over the medial knee compartment, sudden or "springing" intraarticular movements and pseudolocking of the joint. Similar plicae occur after traumatic joint contusion, with meniscus disease, or more rarely with arthrosis deformans. Histologically they are characterized by band-like fibrosed evaginations of the synovial membrane and of the synovial fat and connective tissue into the joint spaces. The following therapeutic suggestions, based on the personal experience of 15 cases, are made in the knowledge that significant inflammatory or proliferative arthritic changes can be excluded: the plica can be cut through under arthroscopy; chondromalacial defects, directly or indirectly caused by plical rubbing, of the medial femoral condyle and the medial patella can be removed, also under arthroscopic control, with an electric razor. Arthrotomy is no longer needed in most cases.