Radiographic findings after duodenal surgery (author's transl)]

A gastroduodenostomy as part of partial gastric resection may change function and morphology of the duodenum in a typical fashion. End to side anastomosis may produce a blind pouch. An end to end anastomosis may lead to postanastomotic dilatation, which may mimick a duodenal bulb (a so called "neo -- or pseudobulb"). Abnormal duodenal peristalsis with atony may follow vagotomy, pyloroplasty, gastroduodenostomy or excisional duodenal biopsy and may thus result in functional obstruction. A blind loop syndrome may develop after bypass procedures for duodenal stenosis.     

Influence of age and of desmotropic drugs on the step phenomenon observed in rat skin

Summary Comprehensive analysis of the mechanical properties of rat skin revealed the step phenomenon. This particular observation was made after constant strain rate (analysis of stress strain curves) as well as after constant load (creep experiments). Relative low extensions or low loads were necessary to provoke the steps. In most cases two, sometimes three steps were observed. The step phenomenon was found mainly in skin strips punched out perpendicularly to the body axis. Probably some bonds in the fibrous network are broken giving way to additional elongation whereafter stronger links take over the stress. Since earlier studies demonstrated a pronounced influence of age and of desmotropic drugs on mechanical properties at ultimate load, e.g., tensile strength, ultimate modulus of elasticity, and ultimate strain, also the step phenomenon was studied under these conditions. In stress-strain experiments most of the steps were found at the ages of 2 and 4 months. Total stress loss and total work loss due to the steps were the highest at the age of 4 months. If, however, these values were calculated as percentage of ultimate values, the highest figures were found in young animals. Elongation gain due to the steps also showed a maximum at time of maturation, e.g., 4 months. Similar findings were achieved in creep experiments at medium load (200 g). After treatment with prednisolone acetate more steps and after treatment with d-penicillamine fewer steps were observed. In stress-strain experiments total stress loss and total work loss due to steps were more than twice as high than controls after prednisolone treatment and only one half after d-penicillamine. If calculated as percentage of ultimate stress or percentage of work input, these changes disappeared because of similar changes at ultimate load. However, elongation gain due to steps, which was not significantly influenced by prednisolone acetate but significantly decreased by d-penicillamine, showed the same changes when calculated as percentage of ultimate strain. Under all conditions the step phenomenon mainly influenced the extension parameters. The data presented here confirm earlier observations that mechanical properties at low loads or low and medium extensions show at least to some extent a different pattern under the influence of maturation and age and after treatment with desmotropic drugs compared to the mechanical parameters at ultimate load.     

MAO inhibition and the effects of centrally administered LSD,serotonin, and 5-methoxytryptamine on the conditioned avoidance response in rats

Pretreatment with the MAO-inhibitors iproniazid, clorgyline, or deprenyl abolishes the effects of LSD on the conditioned avoidance response (CAR) in rats. The effects of serotonin (5-HT) and 5-methoxytryptamine (5-MT) are greatly potentiated by these substances. Brain levels of LSD are not affected by MAO inhibition whereas levels of 5-HT and 5-MT are significantly elevated. It is postulated that the decreased behavioral response to LSD is the result of MAO inhibitor-induced changes whereas the increased response of 5-HT and 5-MT results from increased brain levels of these compounds.     

In vitro germ cell models for the detection of fertility impairment

Pluripotent embryonic carcinoma cells and pluripotent embryonic stem cells established from undifferentiated cells of an early mouse embryo were investigated for induction of proliferation inhibition, sister chromatid exchanges (SCE) and single-strand breaks by treatment with various germ cell mutagens. The comparison of malignant cells with nonmalignant cells showed an increased sensitivity of nonmalignant cells independent of their state of differentiation. Mitomycin C (MMC) inhibited the proliferation of nonmalignant cells at a concentration of 10(-6) M but did not affect growth of the teratocarcinoma cell line P19. There were no differences between the investigated cell lines at a lower MMC concentration. At the concentration of 10(-6) M MMC the sister chromatid exchanges of P19 were enhanced up to 41 SCE per metaphase. Testing of another germ cell mutagen, ethylnitrosourea (ENU), gave similar results: a decreasing generation time of nonmalignant cell lines after treatment with 1 mM ENU and no effect on the teratocarcinoma cells. This concentration also induced a high number of SCE. Single-strand breaks could be produced by exposure to methanmethylsulphonate (MMS). 56.3% of embryonic stem cell DNA was passing through the filter after MMS treatment. In contrast to the embryonic stem cells, only 35.6% of teratocarcinoma DNA was affected.     

Expression of her-2/neu on acute lymphoblastic leukemias: implications for the development of immunotherapeutic approaches.

Her-2/neu is a tumor-associated antigen that is expressed on several adenocarcinomas and correlates with poor prognosis. In a previous study (H. J. Bühring et al., Blood, 86: 1916-1923, 1995), it has been demonstrated that Her-2/neu expression can be detected on blast cells from patients with hematological malignancies including acute lymphoblastic leukemia (ALL). Here, we show that Her-2/neu-specific CTLs induced in vitro using peptide-pulsed dendritic cells efficiently lyse primary ALL blasts constitutively expressing both Her-2/neu and human leukocyte antigen A2 in an antigen-specific and MHC-restricted manner. Furthermore, we analyzed the feasibility of this approach in an autologous setting and induced Her-2/neu-specific CTLs using dendritic cells generated from peripheral blood mononuclear cells from an ALL patient that were pulsed with peptides or transfected with in vitro-transcribed Her-2/neu mRNA. Our data demonstrate that Her-2/neu could be used as a potential target for the application of Her-2/neu-directed treatment strategies in ALL including vaccination approaches.     

Quantitative tumor apoptosis imaging using technetium-99m-HYNIC annexin V single photon emission computed tomography.

PURPOSE: Radiolabeled annexin V may allow for repetitive and selective in vivo identification of apoptotic cell death without the need for invasive biopsy. This study reports on the relationship between quantitative technetium-99m- (99mTc-) 6-hydrazinonicotinic (HYNIC) radiolabeled annexin V tumor uptake, and the number of tumor apoptotic cells derived from histologic analysis. PATIENTS AND METHODS: Twenty patients (18 men, two women) suspected of primary (n = 19) or recurrent (n = 1) head and neck carcinoma were included. All patients underwent a spiral computed tomography (CT) scan, 99mTc-HYNIC annexin V tomography, and subsequent surgical resection of the suspected primary or recurrent tumor. Quantitative 99mTc-HYNIC annexin V uptake in tumor lesions divided by the tumor volume, derived from CT, was related to the number of apoptotic cells per tumor high-power field derived from terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling (TUNEL) assays performed on sectioned tumor slices. RESULTS: Diagnosis was primary head and neck tumor in 18 patients, lymph node involvement of a cancer of unknown primary origin in one patient, and the absence of recurrence in one patient. Mean percentage absolute tumor uptake of the injected dose per cubic centimeter tumor volume derived from tomographic images was 0.0003% (standard deviation [SD], 0.0004%) at 1 hour postinjection (PI) and 0.0001% (SD, 0.0000%) at 5 to 6 hours PI (P =.012). Quantitative 99mTc-HYNIC annexin V tumor uptake correlated well with the number of apoptotic cells if only tumor samples with no or minimal amounts of necrosis were considered. CONCLUSION: In the absence of necrosis, absolute 99mTc-HYNIC annexin V tumor uptake values correlate well with the number of apoptotic cells derived from TUNEL assays.     

Erste klinische Erfahrungen mit dreidimensionalem Ultraschall des Gehirns bei Neugeborenen

Zusammenfassung Fragestellung: Ausgehend von eigenen Erfahrungen mit der 3dimensionalen Echokardiographie wurde versucht, auch ultrasonographische transfontanelle Studien 3dimensional zu rekonstruieren und auf ihren Informationsgehalt zu untersuchen. Methode: Es wurden 16 Neugeborene und S?uglinge (Alter 4 Tage – 3 Monate, Median 12 Tage) untersucht. Ein konventioneller 5-MHz-Schallkopf wurde auf der anterioren Fontanelle plaziert und von einem computergesteuerten Motor im inneren Lumen eines offenen Zylinders um 180° um seine vertikale Achse gedreht. Bei jeder Drehung um jeweils 1° wurde eine Schicht des Gehirns aufgenommen, so da? 180 Schichten erhalten wurden, welche den 3dimensionalen Datensatz bilden. Innerhalb des Datensatzes k?nnen beliebig im Raum orientierte Schnittebenen rekonstruiert werden. Ergebnisse: Bei allen Patienten gelang es, Datens?tze aufzunehmen, welche qualitativ so gut waren, da? sie sp?ter 3dimensional rekonstruiert werden konnten. Die Daten konnten ohne Sedierung und in weniger als 60 s aufgenommen werden. Rekonstruktionen des Gehirns dauerten 2–33 min. Es konnten neue transversale Schnittebenen des Sch?dels rekonstruiert werden, welche bisher nicht erh?ltlich waren. Neue Informationen konnten über subarachnoidal gelegene Hirnl?sionen sowie die r?umliche Ausdehnung von Parenchymblutungen gewonnen werden. Schlu?folgerungen: Dieses neue bildgebende Verfahren k?nnte in Zukunft quantitative und qualitative diagnostische Informationen der herk?mmlichen Ultrasonographie verbessern.      

Breast cancer screening

Radiographic imaging of the breast began in the early years of the twentieth century. Continuous advances in film quality, energy sources, targets, grids, and filters have all contributed to superior image resolution. Federal quality standards now regulate screening mammography, and mass screening for breast cancer has become widely accepted in the United States. Wider application of screening has resulted in a dramatic apparent increase in incidence rates of breast cancer; a large proportion of this increase is in ductal carcinoma in situ. During the past 30 years, nine prospective, randomized trials to evaluate the ability of screening mammography to reduce mortality from breast cancer have been completed. These trials show a 30% reduction in mortality for women ages 50–69 years, but the benefit to women aged 40–49 years remains uncertain. This uncertainty is largely attributable to the lack of properly designed and conducted studies to evaluate screening efficacy in younger women. Although there is no biological reason to predict poor screening performance in the younger age groups, the sensitivity of screening mammography is lower in younger women. Additional data suggest that screening intervals longer than 12 months are ineffective in women younger than 50 years. With shorter screening intervals, the cost associated with screening mammography is comparable to other life-saving measures widely applied in the population. New breast imaging techniques hold promise for superior image quality, but they remain investigational as tools for mass screening. Until primary prevention of breast cancer is a reality, mass screening remains available to reduce mortality from breast cancer.