Modeling human peri-implantation placental development and function†.

It is very difficult to gain a better understanding of the events in human pregnancy that occur during and just after implantation because such pregnancies are not yet clinically detectable. Animal models of human placentation are inadequate. In vitro models that utilize immortalized cell lines and cells derived from trophoblast cancers have multiple limitations. Primary cell and tissue cultures often have limited lifespans and cannot be obtained from the peri-implantation period. We present here two contemporary models of human peri-implantation placental development: extended blastocyst culture and stem-cell derived trophoblast culture. We discuss current research efforts that employ these models and how such models might be used in the future to study the "black box" stage of human pregnancy.

Migration pattern, morphology and viability of cells suspended in or sealed with fibrin glue: a histomorphologic study.

INTRODUCTION: We studied the migration pattern, morphology and viability of cells suspended in five different fibrin glues. Besides this, the behaviour of chondrocytes seeded on porous matrices comprising different collagen types sealed with fibrin glue was investigated. MATERIAL AND METHODS: In an experiment A, cell suspension (0.5x10(6) cells) was incubated with different fibrin glues. Experiment B was set up to evaluate chondrocytes migration either through a collagen I/III (Chondro-Gide, Geistlich Biomaterials, Switzerland) or collagen II matrix sealed with different fibrin glues in a perfusion chamber system. Analysis were performed by lightmicroscopy (Mayer's hematoxylin-eosin; Masson-Goldner; TUNEL test) and by transmission and scanning electron microscopy. All fibrin glues were measured for TGF-beta 1 and 2 with a specific ELISA. RESULTS: After incubation of cell suspension in autologous fibrin glue, the morphology of cells is chondrocyte-like. Spindly, process-bearing cells were seen in commercial fibrin glue. Cells suspended in commercial fibrin glue revealed a significant higher percentage of TUNEL positive cells compared to fibrin tissue adhesives mixed with autologous serum (p=0.006). The TGF-beta 1 and 2 concentration was significantly higher in partial autologous fibrin sealant (PAF) compared to their commercial counterparts (p=0.001). Cells seeded on the collagen I/III matrix retained their chondrocytic morphology, while in the type II collagen matrix the chondrocytes displayed a fibroblastic phenotype. The ratio of TUNEL positive cells for the collagen I/III matrix was significantly surpassed by the values, when a collagen II matrix was used (p=0.008). No ingrowth of cells was seen in any of the experimental conditions. CONCLUSION: Partial autologous fibrin glue and collagen I/III matrices are favourable in respect to migration pattern, morphology and viability, but definitive conclusions can only be drawn after in vivo studies. This will be addressed in future animal studies.

Matrix testing for urothelial tissue engineering.

INTRODUCTION: Surgical reconstruction of the bladder is associated with many well-known complications. Tissue engineering is under discussion as a potential therapeutic strategy and many of the proposed benefits are of special interest for children. Biomaterials play a key role in tissue engineering. Many materials have been proposed for the experimental reconstruction of the bladder and urethra. They determine the biological and mechanical characteristics of the reconstructed tissues. Most publications focus on a single material. In order to identify the most suitable biomaterial it was the aim of this study to compare biological and mechanical features of different biomaterials seeded with urothelial cells in vitro. MATERIALS AND METHODS: Commercially available biomaterials (Biogide, Ethisorb, Lyoplant, SIS, Vicryl, Xenoderm) of biologic or synthetic origin were seeded with urothelial cells. Cell-matrix constructs were cultured and investigated by scanning electron microscopy for surface structure and cell morphology. They were also subjected to extension until failure and the force required was reported as f (max). Values obtained and curve shape were compared to specimens of bladder mucosa and submucosa. RESULTS: Cell adhesion and morphology showed marked differences between materials. Cell shape varied from single spherical cells to confluent layers of flat urothelium. f (max) ranged from 0.02 N to 48.86 N for tested materials and 1.19 N for native bladder mucosa/submucosa. DISCUSSION: The materials showed marked differences in biological and mechanical features in vitro. Cells cultured on biogenic matrices were more similar to native urothelium. Most of the tested materials showed different curve shapes and higher f (max) values than native bladder mucosa.

Ifosfamide, carboplatin and etoposide combined with 41.8 degrees C whole body hyperthermia for malignant pleural mesothelioma.

We performed a phase II study combining 41.8 degrees C whole body hyperthermia with ICE chemotherapy, i.e. ifosfamide (5 g/m(2)), carboplatin (300 mg/m(2)) and etoposide (150 mg/m(2) on days 2 and 3), administered every 4 weeks, for patients with malignant pleural mesothelioma. Of 27 chemonäive, non-metastatic patients enrolled, 25 patients were evaluable for response. Overall response rate was 20% (five partial remissions; 95% CI 8.9-39.1%). Median survival time from the start of treatment for all patients was 76.6 weeks (95% CI 65.4-87.8 weeks). Progression free survival for all patients measured 29.6 weeks (95% CI 24.4-34.7 weeks). One year overall survival was 68% and 2 year overall survival was 20%. Major treatment toxicities included grade 3/4 neutropenia and thrombocytopenia in 74 and 33% of treatment cycles, respectively. One patient died due to sepsis. These promising results are consistent with continued clinical investigation; a phase III clinical trial with whole body hyperthermia as the independent variable has been initiated.

Hyperthermia and mafosfamide in a human-derived malignant pleural mesothelioma cell line.

PURPOSE: Diffuse malignant pleural mesothelioma is the most common primary pleural malignancy. At the beginning of the last century, this tumor was of minor incidence. Meanwhile, the use of asbestos has led to and is still leading to a rise in pleural mesothelioma incidence. There is no standard therapy for this highly aggressive disease and the development of new therapeutic strategies is imperative. METHODS: We, therefore, investigated the morphological and pharmakokinetic effects of a combined thermochemotherapy consisting of the administration of different dosages of mafosfamide with and without the application of a 1-h hyperthermia at 41.7 degrees C on the human biphasic malignant pleural mesothelioma cell line MSTO-211H. After therapy, cells were prepared for light and electron microscopy. BrdU-incorporation for the S-phase fraction, TUNEL-labeling for detection of apoptosis, and quantitative assessments using the MTT assay were performed. RESULTS: Our results demonstrate that the combination of mafosfamide with hyperthermia leads to qualitatively and quantitatively enhanced cellular damage compared to monotherapy. During combined thermochemotherapy, cell damage and death is already induced at lower mafosfamide concentrations than without hyperthermia which suggests an additive effect from hyperthermia to the action of the alkylating drug mafosfamide. Cell death thereby mostly occurs as necrotic cell death rather than as apoptosis, although in a combined thermochemotherapy apoptosis is induced temperature-dependently, when comparing temperatures from 37 degrees C to 43 degrees C. CONCLUSIONS: We suggest that the effect of substances such as ifosfamide and cyclophosfamide which are in clinical use, might be enhanced by the combination of local or regional hyperthermia in order to improve the therapeutical index of these substances in the treatment of pleural mesothelioma.

Friulimicins: novel lipopeptide antibiotics with peptidoglycan synthesis inhibiting activity from Actinoplanes friuliensis sp. nov. II. Isolation and structural characterization.

Four novel lipopeptide antibiotics, friulimicins A, B, C, and D, were isolated from cultures of Actinoplanes friuliensis HAG 010964 after fermentation in different nutrient media. The new compounds were separated by ion-exchange chromatography from the acidic lipopeptides of the amphomycin type also present in the culture fluid, compounds A-1437 A, B, E, and G. The principal constituent friulimicin B, C59H94N14O19, was structurally characterized by mass spectrometric investigations of its hydrolysis and partial degradation products and by sequencing of the cyclic acyl peptide. The NMR data of friulimycin B and the amphomycin constituent A-1437 B were completely assigned by a variety of 2-D experiments, and confirmed the structures determined by mass spectrometry. All 8 lipopeptides possess an identical peptide macrocycle as their central element, linked via a diaminobutyric acid N-terminal either to an acylated asparagine residue or, in the case of the amphomycin series, to an acylated aspartic acid residue. The structures of the amphomycins have now been revised to take account of the peptide framework described herein and the determined cis-configuration of the exocyclic double bond. As a consequence of their higher isoelectric points, the new compounds friulimicin A, B, C, and D have different properties than the amphomycins.

Cefodizime, an aminothiazolylcephalosporin. V. Synthesis and structure-activity relationships in the cefodizime series.

The synthesis as well as in vitro antibacterial activity and pharmacokinetic behavior of cefodizime (HR 221, 1a), its analogs and derivatives is described. In this comparison, cefodizime stands out for its balance between its high antibacterial activity, prolonged elimination half-life and high AUC in mice and dogs.

3874 H1 and H3, novel antifungal heptaene antibiotics produced by Streptomyces sp. HAG 003874.

New antifungal antibiotics, designated as 3874 H1 and H3, were discovered in the fermentation broth of the strain Streptomyces sp. HAG 003874. The compounds were obtained as yellow powders after sequential purification by chromatography on MCI Gel CHP20P, Fractogel HW-40 and ODS reversed phase chromatography. On the basis of the results of spectroscopic analysis, it was found that 3874 H1, C58H86N2O18, MW 1098, belongs to the p-aminoacetophenone containing family of heptaene antibiotics, while 3874 H3, C57H87NO18, MW 1073, is a non-aromatic heptaene. In addition to these, a minor component, 3874 H2, C59H88N2O18, MW 1112, a N-methyl derivative of 3874 H1 has been detected. The structures were elucidated through mass spectral analyses and 1-D and 2-D homonuclear and heteronuclear NMR data. The outstanding physico-chemical feature of 3874 H3 is its improved solubility. The new heptaenes are potent antifungal compounds with broad activity spectra, encompassing dermatophytes, yeasts and filamentous fungi.

Ala(0)-actagardine, a new lantibiotic from cultures of Actinoplanes liguriae ATCC 31048.

The actagardine-producing strain Actinoplanes liguriae ATCC 31048, forms an additional lantibiotic when it is cultured on mannitol and soya meal. The new compound, Ala(0)-actagardine (1), has been isolated by solid-phase extraction followed by a two-step chromatographic separation. The molecular formula of 1 is C84H129N21O25S4. Its chemical structure was determined by 2D-NMR analysis and was further confirmed by an amino acid analysis, Edman degradation, and partial synthesis from actagardine. 1 exhibits a slightly higher biological activity than the parent compound actagardine. The synthetic analogs Lys(0)-actagardine (2) and Ile(0)-actagardine (3) demonstrate also antibacterial activities and emphasize the importance of the N-terminus for further derivatization.

Differences in morphology and cytoskeleton of MCF-7 and MX-1 cells after therapy with OH-tamoxifen and the pure estrogen antagonist ZM 182780. An immunofluorescence and scanning electron microscopic study.

The adjuvant endocrine therapy of breast cancer with non-steroidal antiestrogens of the triphenylethylene-type such as tamoxifen is clinically well established, and pure steroidal antiestrogens are being introduced in clinical trials to circumvent the probable occurrence of tamoxifen resistance. Nevertheless, there do still remain some unsolved questions about the exact mechanisms of these substances. We therefore investigated the different effects of 4-OH-Tamoxifen (OHT), a non-steroidal antiestrogen, versus ZM 182780, a pure steroidal antiestrogen, on the morphology and on the cytoskeleton of MCF-7 (estrogen receptor-positive) and MX-1 (estrogen receptor-negative) cells. For this purpose cells were treated for 2, 5 and 7 days with OHT, ZM182780 and different concentrations of beta-estradiol. Interestingly, in scanning electron microscopy, MCF-7 cells showed more differentiation by forming three-dimensional structures such as acini or tubule-like structures under ZM 182780 therapy than with OHT. As expected, MX-1 cells showed no effects after ZM 182780-therapy, but OHT led to a decrease in the number of these cells and produced a fibroblast-like appearance of the estrogen receptor-negative MX-1 cells. The following immunocytochemical experiments on the tubulin, vimentin, cytokeratin and actin cytoskeleton surprisingly did not show marked differences within the morphologically differentiated ZM 182780-treated population compared to the control group of MCF-7 cells. Only the OHT-treated cells of both, the ER(+) and the ER(-) cells, showed a rearrangement of actin filaments and cytokeratin which appeared even more pronounced within the ER(-) MX-1 cells. No experimental group showed morphologically detectable changes in tubulin or vimentin distribution. These data suggest a non ER-mediated OHT-effect on the cytoskeleton that also affects the ER(-) cell line MX-1.