beta1-integrin is dispensable for the induction of ErbB2 mammary tumors but plays a critical role in the metastatic phase of tumor progression.

Cross-talk between integrin receptors and activated growth factor receptors has been hypothesized to play a critical role in the initiation and progression of cancer. Despite in vitro evidence documenting the important role of integrin receptors in the regulation of cancer cell proliferation, the relative contribution of the integrin receptors to the initiation and progression of tumors remains unclear. Previous studies with a polyomavirus middle T mammary tumor model have indicated that targeted disruption of beta1-integrin in the mammary glands of these mice completely blocks tumor induction. To further explore the general significance of these observations, we have crossed these conditional beta1-integrin strains to a strain of mice carrying mouse mammary tumor virus/activated erbB2 (herein referred to as the NIC strain). In contrast to the tumor induction block in the polyomavirus middle T model, tumor onset in the beta1-integrin-deficient NIC mice was delayed by only 30 d and was 100% penetrant. This modest effect on tumor induction was not a result of inefficient excision, as all tumors were confirmed as beta1-integrin-null. Animals bearing beta1-integrin-deficient ErbB2 tumors exhibited significantly reduced tumor volume, which was associated with increased tumor cell apoptosis and a reduction in tumor angiogenesis. In addition, beta1-integrin-deficient tumors were compromised in their capacity to metastasize to the lung, a deficiency associated with abrogation of adhesion signaling. Taken together, these observations suggest that, although beta1-integrin is dispensable for the initiation of ErbB2 tumor induction, it plays a critical role in metastatic phase of tumor progression.

Effects of pre- and postpubertal social experience on sexual and social behavior in male and female brown lemmings (Lemmus sibiricus).

The effects of prepubertal social contact and postpubertal mating experience on sexual behavior were examined in male and female brown lemmings (Lemmus sibiricus). Subjects of both sexes were either isolated at weaning (18 days) or then housed with siblings for another 10 days before being isolated. Before testing for sexual behavior at the age of 75 days, half of each group of males received a series of exposures to estrous females and half of each group of females was housed with a stud male. The results of mating tests indicated that whereas prior sexual experience facilitated subsequent copulatory behavior in both sexes, prepubertal interactions subsequently facilitated contact social and sexual behavior in males but did not increase the behavioral scores of females, which engaged in high levels of sexual behavior regardless of prepubertal experience. The effect of prior copulatory activity on male sexual performance could not be attributed to increasing age (i.e., maturational processes) because the behavior of males tested once but at different ages did not differ appreciably. Prepubertal social interaction appeared to predispose males to benefit from sexual experience later in life.

DNA probe for detection of serogroup O157 enterohemorrhagic Escherichia coli.

To develop a probe for the detection of serogroup O157 enterohemorrhagic Escherichia coli (EHEC), plasmid DNA extracts from 16 E. coli strains that hybridized with the CVD419 probe were screened for restriction fragments present in plasmids of serogroup O157 E. coli strains, but not in plasmids of non-O157 E. coli strains. Using a single O157:H7 E. coli strain (639I), 10 serogroup O157 E. coli specific fragments were then removed, radiolabeled and hybridized (42 degrees C) with colony blots of both groups of strains. A 2.0 kb SmaI fragment probe (VPM1) was the most specific for serogroup O157 EHEC. Using a larger set of 41 non-E. coli and 107 E. coli strains from human, animal and meat sources, VPM1 hybridized with all 49 serogroup O157 EHEC strains. None of 8 enterotoxigenic E. coli (ETEC), including serogroup O157 strains, nor any of the 41 non-E. coli with the VPM1 probe. However, this probe hybridized with 5 of 50 non-O157 E. coli which were verotoxin (VT) or CVD419 probe-positive. Increased hybridization stringency (45 degrees C) reduced the 5 false-positives to 2 negatives and 3 trace responses, which were easily distinguishable from positive responses.

Oncology applications of flow cytometry.

The application of flow cytometry in evaluation of neoplasms is reviewed, with emphasis on DNA content analysis and surface-membrane antigen analysis. By measuring total nuclear DNA content one can determine the ploidy status and S-phase fraction of tumor cells. Aneuploidy, an abnormal DNA content, is a marker of malignancy and often a predictor of poor prognosis in a number of tumor categories. S-phase fraction reflects the proliferative activity of the tumor and is therefore related to the aggressiveness of the tumor. Surface-membrane antigen analysis of hematologic malignancies using monoclonal antibodies is useful in determining lineage and differentiation of tumor cells. This information is helpful in diagnosis and monitoring of patients and also has prognostic values. The flow cytometry is a new tool for the management of cancer patients because of its role in diagnosis, monitoring, and prognosis of tumors.

Postretention changes in canine position. Results of a long-term follow-up.

The aim of the present study was to evaluate sagittal, vertical and transverse changes in canine position and a possible correlation with relapse of lower anterior crowding. From a sample with a long-term follow-up of 15.7 +/- 4.4 years after treatment, patients with a full dentition were enrolled in the study. Post-treatment and long-term follow-up casts of 117 patients were measured and statistically analyzed. A decrease in intercanine width was found between post-treatment and long-term follow-up records, with more lingual inclination of the mandibular canine axis in the transverse plane. There was a significant correlation between maxillary and mandibular canine inclination. Concomitant changes were an increase in lower anterior crowding and a decrease in mandibular intercanine width. Relapse of anterior crowding has a multifactorial etiology. The results of this study suggest a possible influence of the canines. Functional causes in particular might have a profound influence and should be considered during treatment planning.

Bond strength of a fluoride-releasing bracket adhesive. Experimental study.

The aim of the study was to examine a new fluoride-releasing light-cured filling composite for its bonding and debonding qualities when used as a bracket adhesive. The material investigated was a hybrid composite containing a chemically modified fluoride apatite, which is claimed to provide the enamel with phosphate, calcium, and fluoride ions in the presence of an acid pH, recharging its resources of these ions through fluoride-containing toothpastes used in daily oral hygiene. Concurrently suitability as an enamel conditioner was tested in a new self-etching primer, which does not require water rinsing but is gently air dried instead. For comparison a conventional light-cure single-component adhesive was used together with 37% orthophosphoric acid. After application of the respective conditioners, mesh-backed metal brackets were bonded to 20 human premolars in each of the 2 adhesive groups and subjected to a shear test. Bond failure location was evaluated using the Adhesive Remnant Index (ARI). Average bond strength of the experimental bracket adhesive and the conventional etchant was 8.96 MPa. Conditioning with the self-etching primer led to a decrease of mean shear bond strength values to 6.55 MPa. Highest bond strength was determined in the control group (12.19 MPa). The bond strength results obtained in the shear test recommend the new material as a bracket adhesive to be used with orthophosphoric acid for etching.

Integrin-linked kinase has a critical role in ErbB2 mammary tumor progression: implications for human breast cancer.

Elevated expression of the integrin-linked kinase (ILK) has been observed in a variety of cancers and has been further correlated with poor clinical outcome. Here, we show that mammary epithelial disruption of ILK results in a profound block in mammary tumor induction. Consistent with these observations, inhibition of ILK function in ErbB2-expressing cells with small molecule inhibitor or RNA interference resulted in profound block in their in vitro invasive properties due to the induction of apoptotic cell death. The rare ILK-deficient tumors that eventually arose overcame this block in tumor induction by an upregulation of ErB3 phosphorylation. These observations provide direct evidence that ILK has a critical role in the initiation phase of ErbB2 tumor induction.

Evaluation of an antimicrobial and fluoride-releasing self-etching primer on the shear bond strength of orthodontic brackets.

The enhanced risk of dental caries is one negative side-effect of fixed appliances. A new antimicrobial and fluoride-releasing self-etching bonding system (Clearfil Protect Bond) has been introduced in restorative dentistry and clinical studies have already shown the potential for this primer to be used clinically with effective antiplaque properties. Therefore, this in vitro study was conducted in order to evaluate the new primer in comparison with a conventional bonding preparation. One hundred and twenty extracted human teeth were randomly divided into three groups of 40 specimens each (20 incisors, 20 premolars). In group 1 a conventional bonding procedure was used (etching, Transbond XT), in group 2 the new primer was used according to the manufacturer's recommendations when bonding to intact enamel, while in group 3 the new primer was used without prior etching. Shear bond strength (SBS) was measured with a universal testing machine and the adhesive remaining after debonding was determined using an optical microscope at x10 magnification. The adhesive remnant index was used in order to assess the mode of failure. No enamel fractures were detected in any of the specimens. In all groups acceptable bond strengths were observed. The only statistically significant difference (P = 0.004) was found for the incisors in group 2, which showed the highest mean SBS (17.46 MPa). Considering the acceptable bond strength and the mode of failure, use of the new primer without prior etching is recommended in patients with fixed appliances. Further in vivo studies will be carried out in order to evaluate clinical performance.

[Clinical relevance of the "cockade phenomenon" in abdominal ultrasonic diagnosis]. / Zur klinischen Relevanz des "Kokardenphänomens" in der abdominellen Ultraschalldiagnostik.

The ultrasonic diagnosis "cockade sign" in patients with unexplained abdominal complaints was investigated by means of endoscopy and X-ray studies of the gastrointestinal tract. The following final diagnoses were established: gastric cancer in 24 patients (16,2%), colonic carcinoma in 31 patients (21%), intraabdominal tumor without infiltration of the GI-tract in 19 patients (12,8%), inflammatory bowel disease in 35 patients (23,6%). In 39 patients (26,4%) no inflammatory or neoplastic process of the GI-tract could be found. Most of these patients were suffering of a spastic colon. If a tumor of the gastrointestinal tract can be made visible by ultrasonography, this may shorten the diagnostic procedure. However, ultrasonic investigation of the abdomen cannot exclude an abdominal inflammatory or neoplastic process. Therefore, it is only useful as a screening procedure.

[Extraintestinal manifestations of Crohn's disease]. / Extraintestinale Manifestationen des Morbus Crohn.

Specific extraintestinal manifestations of Crohn's disease are rare except the involvement of the anal region. Only few case reports have been published concerning Crohn's disease of the lips, the mouth, the hypopharynx, the skin, urogenital tract, bone and joints. However, Crohn's disease of the anal region is of great significance. About 30 % of the patients develope fistulae, fissures, abscesses and perianal edema. The anal disease is often a first important and often missed sign of intestinal M. Crohn. Biopsy and histological investigations of the diseased tissue reveals typical histological changes in up to 60-70 % of the patients with anal disease.

[Sonographic diagnosis in cholestasis (author's transl)]. / Ultraschalldiagnostik bei Cholestase. Ergebnisse einer prospektiven Studie.

In a prospective study, sonographic diagnosis was compared in 156 patients having jaundice or showing clinico-chemical signs of cholestasis, with the final diagnosis obtained via endoscopic-retrograde cholangiography, percutaneous transhepatic cholangiography, surgery or autopsy. The results show that in almost 90 per cent of the cases it is possible to differentiate between intrahepatic and extrahepatic cholestasis via sonography. The limitations of sonography concern the identification of prepapillary bile duct concrements which were present in 30 per cent of the patients. Hence, in most cases it was not possible to supply aetiological pointers towards determining the cause of the bile flow disturbance.

[Whipple's disease with severe gastrointestinal hemorrhage]. / Morbus Whipple mit schwerer Gastrointestinalblutung.

A case report is given of a 54 year old male patient, who had acute, relapsing, life threatening episodes of gastro-intestinal bleeding caused by hemorrhagic gastroduodenitis associated with Whipple's disease. The diagnosis was established by histological examination of duodenum biopsies, which contained the pathognomonic PAS-positive macrophages. The gastroduodenitis healed after treatment with tetracyclines und bleeding stopped consequently. Clinical, pathological, radiological and clinical chemistry findings of patients with Whipple's disease are discussed on the basis of literature.