Diagxxnostic Accuracy of 99mTc-Anti-CEA Immuno- scintigraphy in Patients with Liver Metastases from Colorectal Carcinoma

17 Patienten mit 43 Lebermetastasen kolorektaler Karzinome wurden der Immunszintigraphie (IS) mit 99mTc-markierten monoklonalen Anti-CEA-Antikörpern (BW 431/26) unterzogen. Im Hinblick auf die Gesamtzahl der Raumforderungen wurden Sensitivität und diagnostische Treffsicherheit mit 21% bestimmt, bezogen auf die Patientenzahl betrugen sie 47% (mindestens eine positive Darstellung bei multiplen Metastasen) bzw. 77% bei nur einer Solitärmetastase. Die Sensitivität wurde durch Verwendung der SPECT- Technik nicht wesentlich verbessert. Eine Korrelation mit den Serum-CEA- Spiegeln ließ sich nicht nachweisen. Am besten schienen sich Lebermetastasen mittlerer Größe mit mäßiger Tumornekrose darzustellen. Die Ursache für die geringe Sensitivität ist vor allem in der ausgeprägten unspezifischen Anreicherung 99mTc-markierter Antikörper im RES der Leber zu sehen. Im Augenblick scheint die Immunszintigraphie lediglich eine ergänzende Methode zu konventionellen diagnostischen Maßnahmen darzustellen.

Bonner Venenstudie der Deutschen Gesellschaft für Phlebologie

Ziel: Die Bonner Venenstudie zur Frage der Häufigkeit und Ausprägung von chronischen Venenkrankheiten in der städtischen und ländlichen deutschen Wohnbevölkerung im Alter von 18-79 Jahren fand zwischen dem 13. 11. 2000 und 15. 3. 2002 statt. Es nahmen insgesamt 3072 Probanden teil, die Response-Proportion lag insgesamt bei 59%. Ergebnisse: Eine Beinschwellung in der Anamnese trat bei jedem 6. Mann (16,2%) und bei nahezu jeder 2. Frau (42,1%) auf. Eine kurz zurückliegende ein- oder beidseitige Beinschwellung in den letzten vier Wochen gab jeder 6. Teilnehmer an. Dies entspricht 14,8% (7,9% der Männer, 20,2% der Frauen). Für Gefäßerkrankungen typische Beinbeschwerden innerhalb der letzten vier Wochen gab insgesamt jeder 2. der Probanden (56,4%) an. Bei der Beurteilung der klinischen Ausprägung gemäß der CEAP-Klassifikation fällt auf, dass lediglich 9,6% der Probanden keinerlei Venenveränderungen aufweisen. Bei 59% bestehen isoliert Teleangiektasien oder retikuläre Venen, bei 14,3% Krampfadern (C2) ohne weitere Zeichen einer chronischen venösen Insuffizienz. Auffällig ist, dass bei 13,4% ein prätibiales Ödem im Rahmen von Venenveränderungen zum Untersuchungszeitpunkt vorlag. Demgegenüber liegt die Zahl der fortgeschrittenen Zeichen der chronischen venösen Insuffizienz bei 3,3%. Die Häufigkeit des floriden oder abgeheilten Ulcus cruris lag bei 0,7%. Schlussfolgerungen: Jeder 6. Mann und jede 5. Frau hat somit chronische Veneninsuffizienz (C3–C6). Die Zahlen zeigen, dass Venenkrankheiten insgesamt nach wie vor eine hohe Prävalenz aufweisen, dass aber die schweren Ausprägungen der chronischen venösen Insuffizienz in den vergangenen 20 Jahren zurückgegangen sind.

Radiofrequency Thermal Ablation (RFA) of Liver Tumors: Open Surgical or Percutaneous Approach?

RFA was used to ablate 81 liver lesions: 61 liver metastases and 20 hepatomas. An open surgical approach was adopted in 19 instances (27.5%), 12 of which were simultaneously treated for associated diseases, and percutaneous treatment was adopted in 50 instances (72.5%). The CT liver control at 6 months showed a complete necrosis in 50 lesions (66.3%). The advantages of the percutaneous approach include less invasiveness, reduced postoperative pain, shorter hospitalization, reduced costs and less discomfort in repeating the procedure. In conclusion, radiofrequency liver nodule ablation could be considered, today, as one of the promising and versatile techniques for loco-regional liver cancer control.

Association of Venous Disorders with Leg Symptoms: Results from the Bonn Vein Study 1

OBJECTIVES

The aim was to study the association between venous disorders and leg symptoms in the population based cross sectional Bonn Vein Study 1 (BVS1).

METHODS

A total of 1,350 men and 1,722 women aged 18-79 years were enrolled into BVS1. Chronic venous insufficiency (CVI), varicose veins (VVs), and clinical classes (C-classes/CEAP [Clinical, Etiological, Anatomical, and Pathophysiological]) were determined by clinical and duplex investigation. Leg symptoms (heaviness, tightness, swelling, pain after standing or sitting, pain while walking, muscle cramps, itching, and restless legs) were assessed in a standardized interview. For 2,624 subjects (48.7% male) with complete information on venous disorders, relevant characteristics and information on at least one leg symptom, multivariate logistic regression analysis was performed.

RESULTS

More women (929/63.0%) reported at least one leg symptom within the last 4 weeks than men (560/48.7%). Prevalence of reported symptoms increased with age (45.4% of the 18-29 year olds, 73.9% of the 70-79 year olds). Leg symptoms were more frequent in obese and underweight subjects. As confirmed by clinical and duplex examination 22.6% had VV and 15.8% had CVI. VV (OR: 1.4; CI: 1.1-1.7) and CVI (OR: 1.8; CI: 1.3-2.3) were significantly associated with reporting at least one leg symptom. In particular, there was a positive association of VV and CVI with itching, feeling of heaviness, tightness, swelling, and pain after standing or sitting. C2-C6 showed a statistically significant association with feeling of heaviness, tightness, swelling, and itching, while for pain on walking and muscle cramps this was shifted towards C classes C3-C6 and C3-C4, respectively.

CONCLUSIONS

Venous disorders show significant associations with several leg symptoms. Itching, feeling of heaviness, or tightness seem to be more closely related than other symptoms. The associations between C classes and symptoms seem to be restricted to classes C2 or higher.

Cyanurchloridbelastung in Produktionsbetrieben

Hintergrund

Cyanurchlorid (C3Cl3N3) ist ein weißes kristallines Pulver. Es wird für die Herstellung von Herbiziden benötigt, die in der Landwirtschaft eingesetzt werden. Weitere Verwendung findet es in der Produktion von Textilfarbstoffen und optischen Aufhellern oder der Herstellung von UV-Stabilisatoren für die Plastikindustrie sowie insbesondere für Automobilanwendungen in der Gummiindustrie. Zur Durchführung einer epidemiologischen Längsschnittstudie in drei Cyanurchloridproduktionsbetrieben wurde eine personenbezogene Expositionsermittlung durchgeführt sowie medizinische Response-Größen und wesentliche Kovariablen ermittelt.

Methoden

In den Betrieben Antwerpen, Münchsmünster und Wesseling der Evonik Industries AG wurden für alle länger als ein Jahr im Cyanurchloridbetrieb tätigen, männlichen, aktiven und ehemaligen Mitarbeiter zwischen 1958 und 2007 Cyanurchloridexpositionen, Arbeitsgeschichten, Angaben zum Rauchverhalten, biometrische Grunddaten, Lungenfunktionsparameter sowie Koexpositionen und Vorbelastungen aus vorangegangenen Tätigkeiten erfasst und auf Jahresdatensätze verdichtet. Zudem wurden Angaben zu chronischer Bronchitis, Atemnot, Asthma, chronisch-obstruktiver Bronchitis (COPD, „chronic obstructive pulmonary disease“) und Sensibilisierungsparameter im Querschnitt erhoben. Für die Zuweisung von Expositionen zu personenbezogenen Tätigkeiten wurde eine Job-Exposure-Matrix (JEM) unter Verwendung von Konzentrationsmesswerten und unter Berücksichtigung des Tragens von Schutzmasken entwickelt. Um die Unsicherheit in den Belastungen aufgrund der schmalen Messdatenbasis besser abschätzen zu können, wurden über multiple Expositionsschätzungen 24 Varianten ermittelt.

Ergebnisse

Das Studienkollektiv umfasste 394 exponierte männliche Personen. Das durchschnittliche Alter lag bei 47,5 Jahren (min. = 21, max. = 63, SD = 10,3). Es gab 160 aktive Raucher, 78 Ex-Raucher und 149 Nie-Raucher. Der Mittelwert für die zum Zeitpunkt der letzten Lungenfunktionsuntersuchung aufgelaufenen Rauchmenge lag bei den aktiven Rauchern bei 18,9 Pack years (min. = 0,3, max. = 69,5, SD = 14,9) und bei den Ex-Rauchern bei 19,4 Pack years (min. = 1,2, max. = 105,0, SD = 18,4). Die personenbezogene Durchschnittskonzentration der Cyanurchloridexposition betrug über alle Jahre im Mittel 0,019 mg/m3 (min. = 0,003, max. = 0,044) bei einer Expositionsdauer von durchschnittlich 11,3 Jahren (min. = 0,58, max. = 34). Die kumulierte Gesamtexposition betrug durchschnittlich 0,217 mg/m3-Jahre (min. = 0,005, max. = 0,941). Der Mittelwert der Cyanurchloridkonzentration pro Expositionsjahr lag bei 0,020 mg/m3 (min. = 0,003, max. = 0,051). Insgesamt standen 2983 Untersuchungen der Lungenfunktionsparameter VC (Vitalkapazität, „vital capacity“), FVC (forcierte Vitalkapazität, „forced vital capacity“) und FEV1 (absolute Einsekundenkapazität, „forced expiratory volume in 1 second“) zur Verfügung. Im Durchschnitt nahm jeder Studienteilnehmer an 7,6 medizinischen Untersuchungen mit Lungenfunktionsmessungen teil (min. = 1, max. = 19). Die VC in Prozent vom Sollwert betrug bei der ersten (letzten) Lungenfunktionsuntersuchung jedes Studienteilnehmers im Mittel 100 %, SD = 13,6 % (103 %, SD = 14,6 %). Die FVC in Prozent vom Sollwert lag im Mittel bei 103 %, SD = 14,2 % (103 %, SD = 15,4 %). Die FEV1 in Prozent vom Sollwert betrug im Mittel 99 %, SD = 15,4 % (99 %, SD = 18,3 %). Die FEV1%FVC in Prozent vom Sollwert lag im Mittel bei 99 %, SD = 10,4 % (99 %, SD = 12,2 %).

Diskussion

Die Studie stellt den weltweit umfassendsten Datenbestand zur Ermittlung der gesundheitlichen Auswirkung einer Langzeitexposition gegenüber Cyanurchlorid am Arbeitsplatz bereit. Bezogen auf externe Sollwerte ergaben die Lungenfunktionsmesswerte im Mittel keinen Hinweis auf Auffälligkeiten. Zur epidemiologischen Zusammenhangsanalyse wird in Morfeld u. Noll berichtet [41].

The neural cell adhesion molecule-derived peptide, FGL, attenuates lipopolysaccharide-induced changes in glia in a CD200-dependent manner

Fibroblast growth loop (FGL) is a neural cell adhesion molecule (NCAM)-mimetic peptide that mimics the interaction of NCAM with fibroblast growth factor receptor (FGFR). FGL increases neurite outgrowth and promotes neuronal survival in vitro, and it has also been shown to have neuroprotective effects in vivo. More recent evidence has indicated that FGL has anti-inflammatory effects, decreasing age-related changes in microglial activation and production of inflammatory cytokines. These changes have been associated with an FGL-induced increase in expression of the glycoprotein, CD200, which interacts with its receptor to help maintain microglia in a quiescent state. However whether the FGL-induced anti-inflammatory effects are CD200-dependent has not been examined. The objective of this study was to address this question. Mixed glia were prepared from brain tissue of neonatal wildtype and CD200-deficient mice and preincubated with FGL prior to stimulation with lipopolysaccharide (LPS). Cells were assessed for mRNA expression of markers of microglial activation, CD11b, CD40 and intercellular adhesion molecule 1 (ICAM-1) and also the inflammatory cytokines, interleukin (IL)-1β, IL-6 and tumour necrosis factor (TNF)-α, while supernatant concentrations of these cytokine were also assessed. LPS significantly increased all these parameters and the effect was greater in cells prepared from CD200-deficient mice. Whereas FGL attenuated the LPS-induced changes in cells from wildtype mice, it did not do so in cells from CD200-deficient mice. We conclude that the FGL-induced changes in microglial activation are CD200-dependent and demonstrate that the interaction of astrocytes with microglia is critically important for modulating microglial activation.

ABI derived from the highest and lowest ankle pressure. What is the difference?

AIM

Different modes of ankle-brachial -index (ABI) calculation lead to different information. We looked for the peripheral arterial disease (PAD) prevalence estimated from ABI-high and ABI-low and analysed the effect of age and classical risk factors.

METHODS

Based on the Arteriomobil Project data, ABI was calculated considering the lowest of the four ankle artery pressures (ABI-low) or the higher ankle artery pressure of each leg (ABI-high), respectively. ABI <0.9 were defined to prove PAD.

RESULTS

Prevalence of PAD estimated using ABI-low was much higher than those using ABI- high (15.7% vs. 8.0%). Thus 8% of men and 7.5% of women suspected for PAD were not detected if prevalence rates are based on ABI-high alone. Estimating PAD prevalence only by measuring posterior tibial artery (ATP) pressure, prevalence rates were lowest with 2.4% for the left and 2.7% for the right ATP. Estimating PAD prevalence only by measuring anterior tibial artery pressure, prevalence rates were slightly higher, but still low. ABI-high systematically shows lower prevalence rates compared to ABI-low without divergence of the prevalence rates with increasing age. This parallelism of the curves remained unchanged when prevalence rates were separated for self-reported risk-factors; smoking, hypertension, hypercholesterolemia and diabetes.

CONCLUSION

The presented analysis of the Arteriomobil Project data support the hypothesis that the differences in prevalence rates estimated from ABI-high and ABI-low are mainly determined by anatomic variations of the plantar arch. Additional angiographic controlled studies are necessary to prove this hypothesis.

Nitrification at Low pH by Aggregated Chemolithotrophic Bacteria

A study was performed to gain insight into the mechanism of acid-tolerant, chemolithotrophic nitrification. Microorganisms that nitrified at pH 4 were enriched from two Dutch acid soils. Nitrate production in the enrichment cultures was indicated to be of a chemolithoautotrophic nature as it was (i) completely inhibited by acetylene at a concentration as low as 1 mumol/liter and (ii) strongly retarded under conditions of carbon dioxide limitation. Electron microscopy of the enrichment cultures showed the presence of bacteria that were morphologically similar to strains of known chemolithotrophic nitrifying genera. Many of the enriched bacteria, in particular those that were identified as ammonium oxidizers, were aggregated. Filtration experiments indicated that aggregated cells were able to nitrify at low pH, whereas single cells were not. It is hypothesized that cells inside the aggregates are protected against the toxicity of nitrous acid. Nitrification by aggregated chemolithoautotrophic bacteria may be the dominating process of nitrate formation in many acid soils as it does not appear to depend on the existence of microsites of high pH (acid-sensitive autotrophic nitrification) or on the availability of organic carbon (heterotrophic nitrification).

Dimerization effect of sucrose octasulfate on rat FGF1

Fibroblast growth factors (FGFs) constitute a family of at least 23 structurally related heparin-binding proteins that are involved in regulation of cell growth, survival, differentiation and migration. Sucrose octasulfate (SOS), a chemical analogue of heparin, has been demonstrated to activate FGF signalling pathways. The structure of rat FGF1 crystallized in the presence of SOS has been determined at 2.2 A resolution. SOS-mediated dimerization of FGF1 was observed, which was further supported by gel-filtration experiments. The major contributors to the sulfate-binding sites in rat FGF1 are Lys113, Lys118, Arg122 and Lys128. An arginine at position 116 is a consensus residue in mammalian FGF molecules; however, it is a serine in rat FGF1. This difference may be important for SOS-mediated FGF1 dimerization in rat.

Experimental gastritis in mice enhances anxiety in a gender-related manner

There is a gender-related comorbidity of pain-related and inflammatory bowel diseases with psychiatric diseases. Since the impact of experimental gastrointestinal inflammation on the emotional-affective behavior is little known, we examined whether experimental gastritis modifies anxiety, stress coping and circulating corticosterone in male and female Him:OF1 mice. Gastritis was induced by adding iodoacetamide (0.1%) to the drinking water for at least 7 days. Inflammation was assessed by gastric histology and myeloperoxidase activity, circulating corticosterone determined by enzyme immunoassay, anxiety-related behavior evaluated with the elevated plus maze and stress-induced hyperthermia tests, and depression-like behavior estimated with the tail suspension test. Iodoacetamide-induced gastritis was associated with gastric mucosal surface damage and an increase in gastric myeloperoxidase activity, this increase being significantly larger in female mice than in male mice. The rectal temperature of male mice treated with iodoacetamide was enhanced, whereas that of female mice was diminished. The circulating levels of corticosterone were reduced by 65% in female mice treated with iodoacetamide but did not significantly change in male mice. On the behavioral level, iodoacetamide treatment caused a decrease in nocturnal home-cage activity, drinking and feeding. While depression-related behavior remained unaltered following induction of gastritis, behavioral indices of anxiety were significantly enhanced in female but not male mice. There was no correlation between the estrous cycle and anxiety as well as circulating corticosterone. Radiotracer experiments revealed that iodoacetamide did not readily enter the brain, the blood-brain ratio being 20:1. Collectively, these data show that iodoacetamide treatment causes gastritis in a gender-related manner, its severity being significantly greater in female than in male mice. The induction of gastritis in female mice is associated with a reduction of circulating corticosterone and an enforcement of behavioral indices of anxiety. Gastric inflammation thus has a distinct gender-dependent influence on emotional-affective behavior and its neuroendocrine control.

A neural cell adhesion molecule–derived peptide reduces neuropathological signs and cognitive impairment induced by Aβ25-35

By means of i.c.v. administration of preaggregated oligomeric beta-amyloid (Abeta)25-35 peptide it was possible in rats to generate neuropathological signs related to those of early stages of Alzheimer's disease (AD). Abeta25-35-administration induced the deposition of endogenously produced amyloid protein. Furthermore, quantitative immunohistochemistry demonstrated time-related statistically significant increases in amyloid immunoreactivity, tau phosphorylation, microglial activation, and astrocytosis, and stereological investigations demonstrated statistically significant increased neuronal cell death and brain atrophy in response to Abeta25-35. Finally, the Abeta25-35-administration led to a reduced short-term memory as determined by the social recognition test. A synthetic peptide termed FGL derived from the neural cell adhesion molecule (NCAM) was able to prevent or, if already manifest, strongly reduce all investigated signs of Abeta25-35-induced neuropathology and cognitive impairment. The FGL peptide was recently demonstrated to be able to cross the blood-brain-barrier. Accordingly, we found that the beneficial effects of FGL were achieved not only by intracisternal, but also by intranasal and s.c. administration of the peptide. Furthermore, FGL-treatment was shown to inhibit the activity of GSK3beta, a kinase implicated in signaling regulating cell survival, tau phosphorylation and the processing of the amyloid precursor protein (APP). Thus, the peptide induced a statistically significant increase in the fraction of GSK3beta phosphorylated on the Ser9-position, a posttranslational modification known to inhibit the activity of the kinase. Hence, the mode of action of FGL with respect to the preventive and curative effects on Abeta25-35-induced neuropathological manifestations and cognitive impairment involves the modulation of intracellular signal-transduction mediated through GSK3beta.

IL-1beta-induced pro-apoptotic signalling is facilitated by NCAM/FGF receptor signalling and inhibited by the C3d ligand in the INS-1E rat beta cell line

AIMS/HYPOTHESIS

IL-1beta released from immune cells induces beta cell pro-apoptotic signalling via mitogen-activated protein kinases (MAPKs) and nuclear factor-kappaB (NF-kappaB). In neurons, the neural cell adhesion molecule (NCAM) signals to several elements involved in IL-1beta-induced pro-apoptotic signalling in beta cells. Pancreatic beta cells express NCAM, but its biological effects in these cells are unclear. The aim of this study was to investigate whether there is cross-talk between NCAM signalling and cytokine-induced pro-apoptotic signalling.

MATERIALS AND METHODS

Western blotting was used to investigate levels of NCAM and inducible nitric oxide synthase, phosphorylation of Src and MAPKs, and cleavage of caspase-3. MAPK activity was investigated with an in vitro kinase assay. Apoptosis was detected by cleaved caspase-3 and a Cell Death Detection ELISA(plus) assay. NCAM-induced fibroblast growth factor receptor (FGFR) activation was investigated in NCAM(-/-) Trex293 cells where FGFR phosphorylation was measured by Western blotting after NCAM transfection.

RESULTS

Pre-exposure of INS-1E cells to the FGFR-inhibitor SU5402, but not to the Src-inhibitor PP2, dose-dependently inhibited IL-1beta-mediated MAPK activity. A synthetic peptide, C3d, reported to bind NCAM, did not activate MAPK or Akt as reported in neurons but inhibited IL-1beta-induced MAPK activity, thereby mimicking the effect of SU5402. Furthermore, C3d inhibited NCAM-induced FGFR phosphorylation and apoptosis induced by IL-1beta plus IFN-gamma, but did not affect IL-1beta-induced NF-kappaB signalling.

CONCLUSIONS/INTERPRETATION

We suggest that NCAM signalling through FGFR is required for efficient IL-1beta pro-apoptotic signalling by facilitating IL-1beta-induced MAPK activation downstream of the NF-kappaB-MAPK branching point. Further, these data identify a novel function of C3d as an inhibitor of NCAM-induced FGFR activity and of IL-1beta-induced MAPK activation in beta cells.

A neural cell adhesion molecule–derived fibroblast growth factor receptor agonist, the FGL-peptide, promotes early postnatal sensorimotor development and enhances social memory retention

The neural cell adhesion molecule (NCAM) belongs to the immunoglobulin (Ig) superfamily and is composed extracellularly of five Ig-like and two fibronectin type III (F3) modules. It plays a pivotal role in neuronal development and synaptic plasticity. NCAM signals via a direct interaction with the fibroblast growth factor receptor (FGFR). A 15-amino-acid long peptide, the FG loop (FGL) peptide, that is derived from the second F3 module of NCAM has been found to activate FGFR1. We here report that the FGL peptide, when administered intranasally to newborn rats, accelerated early postnatal development of coordination skills. In adult animals s.c. administration of FGL resulted in a prolonged retention of social memory. We found that FGL rapidly penetrated into the blood and cerebrospinal fluid after both intranasal and s.c. administration and remained detectable in the fluids for up to 5 hours.

Contrast-enhanced ultrasonography with SonoVue after infliximab therapy in Crohn's disease

The introduction of biological treatments like monoclonal anti TNF-a antibodies (infliximab), is changing the clinical history of Crohn's disease (CD). The effects of these therapies are monitored emplying clinical indexes of active disease, laboratory parameters, endoscopy and histology, and also with imaging techniques. A new ultrasound contrast agent, SonoVue (Bracco SpA, Milano, Italy), is opening new perspectives in the study of microvasculature of several organs. Aim of this study is to evaluate by SonoVue enhanced ultrasonography (US) the occurrence of modifications in bowel wall microvasculature of CD patients and to correlate them with parameters of disease activity and to follow up the findings during infliximab therapy. After performing a basal color-doppler ultrasonography, the study of the affected bowel loop is performed after i.v. injection of SonoVue and the enhancement is evaluated on a qualitative basis. We report on the preliminary results obtained in twenty patients, eight of which have been treated with three infusions of infliximab (induction cycle) and evaluated at baseline and after the treatment. While at baseline we describe a positive correlation of SonoVue enhancement of the affected bowel loop with CRP, alpha1-glycoprotein and white blood cell number, after infliximab treatment in 6/8 cases a definite improvement was detected. Ultrasonographic evaluation of the changes of bowel wall enhancement after i.v. SonoVue during infliximab therapy might represent an useful, not invasive and relatively low cost imaging modality for the clinical monitoring of activity of small bowel Crohn's disease.

Cell-cycle-dependent regulation of cell motility and determination of the role of Rac1

To study cell motility in different phases of the cell cycle, time-lapse recording by computer-assisted microscopy of unsynchronised cells from three mammalian cell lines (L929, BT4Cn, HeLa) was used for the determination of the displacements of individual cells. The displacements were used for calculation of three key parameters describing cell motility: speed, persistence time and rate of diffusion. All investigated cell lines demonstrated a lower cell displacement in the G2 phase than in the G1/S phases. This was caused by a decrease in speed and/or persistence time. The decrease in motility was accompanied by changes in morphology reflecting the larger volume of cells in G2 than in G1. Furthermore, L-cells and HeLa-cells appeared to be less adherent in the G2 phase. Transfection of L-cells with constitutively active Rac1 led to a general increase in the speed and rate of diffusion in G2 to levels comparable to those of control cells in G1. In contrast, transfection with dominant-negative Rac1 reduced cell speed and resulted in cellular displacements, which were identical in G1 and G2. These observations indicate that migration of cultured cells is regulated in a cell-cycle-dependent manner, and that an enhancement of Rac1 activity is sufficient for a delay of the reduced cell displacement otherwise seen in G2.

Genera-specific immunofluorescence labeling of ammonia oxidizers with polyclonal antibodies recognizing both subunits of the ammonia monooxygenase

Polyclonal antibodies that recognize the two subunits AmoA and AmoB of the ammonia monooxygenase (AMO) were applied to identify ammonia-oxidizing bacteria by immunofluorescence (IF) labeling in pure, mixed, and enriched cultures. The antibodies against the AmoA were produced using a synthetic peptide of the AmoA of Nitrosomonas eutropha, whereas the antibodies against the AmoB had been developed previously is against the whole B-subunit of the AMO [Pinck et al. (2001) Appl Environ Microbiol 67:118-124]. Using IF labeling, the AmoA antibodies were specific for the detection of all species of the genus Nitrosomonas. In contrast, the antiserum against AmoB labeled all genera of ammonia oxidizers of the beta-subclass of Proteobacteria (Nitrosomonas, Nitrosospira, Nitrosolobus, and Nitrosovibrio). The fluorescence signals of the AmoA antibodies were spread all over the cells, whereas the signals of the AmoB antibodies were associated with the cytoplasmic membranes. The specificity of the reactions of the antisera with ammonia oxidizers were proven in pure and mixed cultures, and the characteristic IF labeling and the morphology of the cells enabled their identification at the genus level. The genus-specific IF labeling could be used to identify ammonia oxidizers enriched from various habitats. In enrichment cultures of natural sandstone, cells of the genera Nitrosomonas, Nitrosovibrio, and Nitrosospira were detected. Members of the genus Nitrosovibrio and Nitrosolobus were most prominent in enriched garden soil samples, whereas members of the genus Nitrosomonas dominated in enriched activated sludge. The antibodies caused only slight background fluorescence on sandstone and soil particles compared to oligonucleotide probes, which could not be used to detect ammonia oxidizers on these materials because of strong nonspecific fluorescence.

Lassen sich geschlechtsspezifische Unterschiede bei Venenerkrankungen durch Schwangerschaften und Hormoneinnahme erklären?

AIM OF THE STUDY

Diseases of the venous system are among the most frequently occurring diseases in the German population. However, the last comprehensive population-based German data were obtained in 1979. Since then, diagnostic methods have improved substantially. Here, we examine the prevalence of venous diseases in women and their association with pregnancies and intake of hormones.

METHODS

We conducted a population-based cross-sectional study in Bonn and rural environments (Recruitment period: 11/2000 - 11/2001; response: 59 %; 3072 study participants (1350 men, 1722 women), 18 to 79 years of age; investigation: standardised medical history, physical examination, duplex sonography, photography and CEAP-classification of veins of the legs). The following definitions were used: 1) Varicosis: clinical classification C2-C6 (primary varicosis only, excluding those showing spider-bursts exclusively); 2) Chronic venous insufficiency (CVI): C3-C6. For women, the risk factors examined were the number of pregnancies (P) and intake of hormones. Odds ratios (OR) and 95 % confidence intervals (95 %-CI) were calculated by multiple logistic regression (adjusted for age, region of residence and socioeconomic status). In addition, never pregnant women and men were compared regarding the two outcome variables.

RESULTS

713 participants (23 %) had varicosis and 522 (17 %) CVI. The OR for women (reference group: men) was OR = 1.4, 95 %-CI: 1.25 - 1.79 (varicosis) and OR = 1.2, 95 %-CI: 0.93 - 1.42 (CVI). There was a positive dose-response relationship between the number of pregnancies and varicosis: 1 P: OR = 1.3 (95 %-CI: 0.89 - 1.96), 2 P: OR = 1.4 (95 %-CI: 1.00 - 2.07), 3 P: OR = 1.6 (95 %-CI: 1.05 - 2.41), 4 P: OR = 1.9 (95 %-CI: 1.18 - 3.20), > or = 5 P: OR = 2.2 (95 %-CI: 1.28 - 3.74) and this trend was similar for CVI. Never-pregnant women (n = 518) and men had a similar prevalence. We did not see a consistent effect of intake of hormones in varicosis (OR = 0.9 [95 %-CI: 0.68 - 1.22]), but a negative association with CVI (OR = 0.6 [95 %-CI: 0.47 - 0.89]).

CONCLUSIONS

Our results confirm the known association between diseases of the venous system and pregnancies, which seem to explain a big share of the sex-specific differences in the prevalence of these diseases.

Radiofrequency thermal ablation (RFA) of liver tumors: percutaneous and open surgical approaches

Radiofrequency Thermal Ablation (RFA) of liver tumors is done by percutaneous, laparoscopic and open surgical approach. Selection criteria for percutaneous or open surgical ablation of 65 hepatic lesions are here evaluated in 45 patients treated in a two-years period. Twenty-five patients were males and 20 females, ages ranged from 35 to 80 years (mean 63 years). RFA was performed in 57 procedures, ablating 14 hepatomas and 51 liver metastases. In 10 cases the treatment was repeated twice. Tumor size ranged from 0.5 cm to 8 cm, with a mean of 2.4 cm. Open surgical approach was performed in 14 cases (24.6%), seven of which were simultaneously treated for associated diseases. Percutaneous treatment was adopted in 43 cases (75.4%). A laparoscopic approach was not tempted in any case. Morbidity was 8.8%, mostly in open surgery (4 cases or 28.6%) but in one patient (2.3%) with percutaneous approach. Difference in between the two groups was statistically significant (p=0.013). Overall mortality was 2.2%: one patients deceased for myocardial infarction. The mean length of hospital stay was of 4.1 days for the percutaneous treatment group and 7.6 days for the open surgery approach. Number of the lesions did not interfere with surgical approach. Postoperative CT control showed no differences, in terms of complete ablation of the tumor, between the two groups of patients. Advantages of percutaneous approach include less invasiveness, reduced postoperative pain, shorter hospitalization, reduced costs and lower discomfort in repeating the procedure. In addition, open surgical RFA allows better cancer staging, avoidance of adjacent organ injury, accessibility to all liver areas and gives the chance to performe simultaneous organ resection. These results are encouraging in making the percutaneous approach of RFA the method of choice in these patients.

Post-training administration of a synthetic peptide ligand of the neural cell adhesion molecule, C3d, attenuates long-term expression of contextual fear conditioning

The neural cell adhesion molecule (NCAM) plays a key role in synaptic plasticity and memory formation. We have recently developed a synthetic peptide, termed C3d, which, through the binding to the first, N-terminal immunoglobulin-like (Ig) module in the extracellular portion of NCAM, has been shown to promote neurite outgrowth and synapse formation in vitro, and to interfere with passive avoidance memory in rats in vivo. In this study, we investigated whether the i.c.v. administration of C3d, either 5.5 h after or 2 days before training, could be effective to modulate the strength at which emotional memory for aversive situations is established into a long-term memory. The effects of the peptide were evaluated in adult male Wistar rats trained in the contextual fear conditioning task. The results indicated that C3d significantly reduced the subsequent long-term retention of the conditioned fear response when administered 5.5 h post-training, as indicated by retention tests performed 2-3 and 7 days post-training. However, this treatment failed to influence conditioning for this task when injected 2 days pre-training. Additional experiments showed that C3d did not influence the emotional or locomotor behaviour of the animals, when tested in the open field task. Furthermore, hippocampal levels of microtubule-associated protein 2 (MAP2), Synaptophysin and NCAM were found unchanged when evaluated by enzyme-linked immunosorbent assay in crude synaptosomal preparations 2 days after peptide i.c.v. injection. Therefore, post-training injection of this synthetic peptide was efficient to attenuate the strength at which memory for contextual fear conditioning was enduringly stored, whilst it did not affect the acquisition of new memories. In addition to further support the view that NCAM is critically involved in memory consolidation, the current findings suggest that the NCAM IgI module is a potential target for the development of therapeutic drugs capable to reduce the cognitive impact induced by exposure to intensive stress experiences.

[Radiofrequency thermal ablation of hepatic nodules: selection criteria for percutaneous treatment]

Radiofrequency thermal ablation (RFA) of liver tumor is done by percutaneous, laparoscopic and open surgical approach. Selection criteria for percutaneous or open surgical ablation of 54 hepatic lesions are here evaluated in 30 consecutive patients. Open surgical approach was performed in 9 cases only, 5 of them due to concomitant treatment of associated diseases. Number and size of the lesions did not interfere with surgical approach. Postoperative CT control showed no differences in terms of complete ablation of the tumor in between the two groups of patients. Percutaneous approach of RFA is gone to be in the future the modality of choice in these patients.

CTC staining and counting of actively respiring bacteria in natural stone using confocal laser scanning microscopy

A method was established for staining and counting of actively respiring bacteria in natural stone by using the tetrazolium salt 5-cyano-2,3-ditolyltetrazolium chloride (CTC) in combination with confocal laser scanning microscopy (CLSM). Applying 5 mM CTC for 2 h to pure cultures of representative stone-inhabiting microorganisms showed that chemoorganotrophic bacteria and fungi-in contrast to lithoautotrophic nitrifying bacteria-were able to reduce CTC to CTF, the red fluorescing formazan crystals of CTC. Optimal staining conditions for microorganisms in stone material were found to be 15 mM CTC applied for 24 h. The cells could be visualized on transparent and nontransparent mineral materials by means of CLSM. A semi-automated method was used to count the cells within the pore system of the stone. The percentage of CTC-stained bacteria was dependent on temperature and humidity of the material. At 28 degrees C and high humidity (maximum water holding capacity) in the laboratory, about 58% of the total bacterial microflora was active. On natural stone exposed for 9 years at an urban exposure site in Germany, 52-56% of the bacterial microflora was active at the east, west, and north side of the specimen, while only 18% cells were active at the south side. This is consistent with microclimatic differences on the south side which was more exposed to sunshine thus causing UV and water stress as well as higher temperatures on a microscale level. In combination with CLSM, staining by CTC can be used as a fast method for monitoring the metabolic activity of chemoorganotrophic bacteria in monuments, buildings of historic interest or any art objects of natural stone. Due to the small size of samples required, the damage to these objects and buildings can be minimized.

Immunological detection of Nitrospira-like bacteria in various soils

Chemolithotrophic nitrite oxidizers were enriched from five different soils including freshwater marsh, permafrost, garden, agricultural, and desert soils and monitored during the cultivation procedure. Immunoblot analysis was used to identify the nitrite oxidizing organisms with monoclonal antibodies, which recognize the key enzyme of nitrite oxidation in a genus-specific reaction [Bartosch et al. (1999) Appl Environ Microbiol 65:4126-4133]. The morphological characteristics of the enriched nitrite oxidizers were additionally studied using transmission electron microscopy (TEM) and fluorescence microscopy. By means of the antibodies and TEM analysis Nitrospira could be clearly identified in enrichment cultures derived from freshwater marsh and from permafrost soil. Nitrospira cells were enriched simultaneously with cells of the genus Nitrobacter when nitrite concentrations of 0.2 g of NaNO2 L(-1) were used. However, in enrichment cultures containing 2 g of NaNO2 L(-1) Nitrobacter was exclusively detected. During fluorescence microscopic observations of DAPI stained samples microcolonies were found in enrichment cultures from freshwater marsh, permafrost, garden, and agricultural soil. They had a similar morphology to Nitrospira-like microcolonies from activated sludge. In conclusion, Nitrospira seems to be not only a common aquatic but also a usual soil bacterium.

The transcription factors CREB and c-Fos play key roles in NCAM-mediated neuritogenesis in PC12-E2 cells

The neural cell adhesion molecule (NCAM) stimulates axonal outgrowth by activation of the Ras-mitogen activated protein kinase (MAPK) pathway and by generation of arachidonic acid. We investigated whether the transcription factors, cyclic-AMP response-element binding protein (CREB) and c-Fos play roles in this process by estimating NCAM-dependent neurite outgrowth from PC12-E2 cells grown in co-culture with NCAM-negative or NCAM-positive fibroblasts. PC12-E2 cells were transiently transfected with expression plasmids encoding wild-type or dominant negative forms of CREB and c-Fos or an activated form of the MAPK kinase, MEK2. Alternatively, PC12-E2 cells were treated with arachidonic acid, the cAMP analogue dBcAMP, or protein kinase A (PKA) inhibitors. The negative forms of CREB and c-Fos inhibited neurite outgrowth mediated by NCAM, arachidonic acid, dBcAMP, or MEK2. Neither CREB nor c-Fos could compensate for the inactivation of the other, indicating that both factors are important in NCAM-mediated neuritogenesis. Treatment of primary hippocampal neurons with a synthetic NCAM peptide ligand known to stimulate neurite outgrowth induced phosphorylation of CREB and expression of c-fos. We thus present evidence that NCAM-mediated neurite outgrowth involves a series of signal transduction pathways, including the cAMP/PKA pathway, targeting c-Fos and CREB.

Intermediate filaments regulate astrocyte motility

Intermediate filaments (IFs) compose, together with actin filaments and microtubules, the cytoskeleton and they exhibit a remarkable but still enigmatic cell-type specificity. In a number of cell types, IFs seem to be instrumental in the maintenance of the mechanical integrity of cells and tissues. The function of IFs in astrocytes has so far remained elusive. We have recently reported that glial scar formation following brain or spinal cord injury is impaired in mice deficient in glial fibrillary acidic protein and vimentin. These mice lack IFs in reactive astrocytes that are normally pivotal in the wound repair process. Here we show that reactive astrocytes devoid of IFs exhibit clear morphological changes and profound defects in cell motility thereby revealing a novel function for IFs.

S100A12 protein is a strong inducer of neurite outgrowth from primary hippocampal neurons

Several members of the S100 family of Ca(2+) binding proteins are at present known to be secreted and to have extracellular activities. We have investigated the neurite inducing potential of extracellularly added S100A12. Human recombinant S100A12 was found to dramatically induce neuritogenesis of hippocampal cells isolated from 17 to 19 days old rat embryos. The response to S100A12 was dependent on the dose in a bell-shaped manner. A 10-fold increase in neurite outgrowth was observed upon treatment with S100A12 in concentrations between 0.1 and 2.0 microM already after 24 h. Exposure to S100A12 for only 15 min was enough to induce neuritogenesis when measured after 24 h, but to obtain a maximal response, S100A12 had to be present in the culture for at least 4 h. The response to S100A12 was abolished by inhibitors of phospholipase C (PLC), protein kinase C (PKC), Ca(2+) flux, Ca(2+)/calmodulin dependent kinase II (CaMKII) or mitogen-activated protein kinase kinase (MEK). Therefore, we suggest that extracellular S100A12 triggers intracellular signal transduction in neurons, involving the classical mitogen-activated protein (MAP) kinase pathway and a phospholipase C-generated second messenger pathway leading to an increase in intracellular Ca(2+) and activation of PKC, ultimately resulting in neuronal differentiation.

Gaseous NO2 as a regulator for ammonia oxidation of Nitrosomonas eutropha

Cells of Nitrosomonas eutropha strain N904 that were denitrifying under anoxic conditions with hydrogen as electron donor and nitrite as electron acceptor were unable to utilize ammonium (ammonia) as an energy source. The recovery of ammonia oxidation activity was dependent on the presence of NO2. Anaerobic ammonia oxidation activity was observed in a helium atmosphere supplemented with 25 ppm NO2 after 20 h. Ammonia oxidation activity was detected after 2-3 days using an oxic atmosphere with 25 ppm NO2. In contrast, ammonia consumption started after 8-9 days under oxic conditions without the addition of NO2; in this case, small amounts of NO and NO2 were detected and their concentrations increased with increasing ammonia oxidation activities. Hardly any ammonia oxidation was detected when nitrogen oxides were removed by intensive aeration. It would seem, therefore, that NO2 is the master regulatory signal for ammonia oxidation in Nitrosomonas eutropha. Anaerobic ammonia oxidation activity was inhibited by the addition of NO. This inhibition was partly compensated by either increasing the NO2 concentration or by using 2,3-dimercapto-1-propane-sulfonic acid as a NO binding substrate. DMPS was inhibitory to nitrification under oxic conditions, while increased amounts of NO or NO2 led to increased oxidation activities.

The metastasis-associated Mts1(S100A4) protein could act as an angiogenic factor

The involvement of Mts1(S100A4), a small Ca(2+)-binding protein in tumor progression and metastasis had been demonstrated. However, the mechanism by which mts1(S100A4) promoted metastasis had not been identified. Here we demonstrated that Mts1(S100A4) had significant stimulatory effect on the angiogenesis. We detected high incidence of hemangiomas--benign tumors of vascular origin in aged transgenic mice ubiquitously expressing the mts1(S100A4) gene. Furthermore, the serum level of the Mts1(S100A4) protein increased with ageing. Tumors developed in Mts1-transgenic mice revealed an enhanced vascular density. We showed that an oligomeric, but not a dimeric form of the Mts1(S100A4) protein was capable of enhancing the endothelial cell motility in vitro and stimulate the corneal neovascularization in vivo. An oligomeric fraction of the protein was detected in the conditioned media as well as in human serum. The data obtained allowed us to conclude that mts1(S100A4) might induce tumor progression via stimulation of angiogenesis.