Effects of Diaspirin Crosslinked Hemoglobin (DCLHb) on microcirculation and local tissue pO2 of striated skin muscle following resuscitation from hemorrhagic shock.

The hemoglobin based oxygen carrier (HBOC) Diaspirin Crosslinked Hemoglobin (DCLHb) has been developed to substitute not only the blood volume, but also to restore the oxygen-carrying properties of blood during hemorrhagic shock. However, it has been suggested that HBOCs may enhance the formation of free oxygen radicals through the release of free iron ions via the Haber-Weiss reaction. The aim of this study was to investigate the effects of DCLHb on the microcirculation, leukocyte-endothelial cell interaction and local tissue oxygenation in striated skin muscle of Syrian golden hamsters during and after resuscitation from hemorrhagic shock.

[The presence of family members in the trauma room].

The fate of multiple trauma patients is witnessed by a considerable number of relatives. Although numerous studies report that the patient's course and treatment success are dependent on the family's confidence as well as its clarification over the clinical situation, scientifically based guidelines for contact with relatives in the context of acute care following severe traumatic injuries do not yet exist. The current guidelines of the European Resuscitation Council recommend the concept of "on scene" presence for the integration of the relatives into acute care in situations of circulatory and heart failure, thus recommending the presence of relatives during acute medical care.

Effects of ultra-purified polymerized bovine hemoglobin on local tissue oxygen tension in striated skin muscle -- an efficacy study in the hamster.

The development of hemoglobin-based oxygen carriers has been propagated for replacement of the oxygen carrying properties of red blood cells for almost one century. Using a Clark-type multi-wire oxygen surface electrode and the dorsal skin fold chamber model of the awake Syrian golden hamster, local tissue pO(2) was analyzed in the thin striated skin muscle before and after administration of an ultra-purified polymerized bovine hemoglobin solution (U-PBHb, Biopure Corp., Boston, Mass.

Quantitative imaging of tumour blood flow by contrast-enhanced magnetic resonance imaging.

Tumour blood flow plays a key role in tumour growth, formation of metastasis, and detection and treatment of malignant tumours. Recent investigations provided increasing evidence that quantitative analysis of tumour blood flow is an indispensable prerequisite for developing novel treatment strategies and individualizing cancer therapy. Currently, however, methods for noninvasive, quantitative and high spatial resolution imaging of tumour blood flow are rare.

Tissue distribution and penetration of 5-ALA induced fluorescence in an amelanotic melanoma after topical application.

Background: Photodynamic therapy (PDT) following topical application of 5-aminolevulinic acid (ALA) is increasingly employed for several types of malignancies. However, data with respect to tissue penetration and distribution of ALA-induced porphyrins after topical application are scarce. Therefore, it was our aim to study tissue distribution and the penetration potency of topically applied ALA.

Active and higher intracellular uptake of 5-aminolevulinic acid in tumors may be inhibited by glycine.

Topical 5-aminolevulinic acid is used for the fluorescence-based diagnosis and photodynamic treatment of superficial precancerous and cancerous lesions of the skin. Thus, we investigated the kinetics of 5-aminolevulinic acid-induced fluorescence and the mechanisms responsible for the selective formation of porphyrins in tumors in vivo. Using amelanotic melanomas (A-Mel-3) grown in dorsal skinfold chambers of Syrian golden hamsters fluorescence kinetics were measured up to 24 h after topical application of 5-aminolevulinic acid (1%, 3%, or 10%) for 1 h, 4 h, or 8 h by intravital microscopy (n = 54).

Pharmacokinetics and selectivity of aminolevulinic acid-induced porphyrin synthesis in patients with cervical intra-epithelial neoplasia.

Photodynamic therapy (PDT), due to its tumor selectivity, represents an alternative approach to diagnose and treat cervical intra-epithelial neoplasia (CIN) without altering normal surrounding tissue. Our aim was to investigate the pharmacokinetics and the selectivity of 5-aminolevulinic acid (5-ALA)-induced porphyrin fluorescence after topical administration, to obtain basic clinical data for future diagnostic fluorescence imaging and PDT protocols for CIN. Twenty-eight non-pregnant women with a cytological diagnosis of low-grade or high-grade squamous intra-epithelial lesions were included.

Effects of diaspirin-cross-linked hemoglobin (DCLHb) on the microcirculation of striated skin muscle in the hamster: a study on safety and toxicity.

Hemoglobin-based oxygen-carrying solutions are reported to exert vasoconstrictor effects and to enhance oxygen radical formation, particularly during ischemia-reperfusion. This study investigates whether diaspirin-cross-linked hemoglobin (DCLHb) affects the microvascular integrity of striated skin muscle. The microcirculation model in the hamster and intravital fluorescence microscopy were applied for investigation of the microvascular changes in striated skin muscle.

Effects of ultra-purified polymerized bovine hemoglobin on the microcirculation of striated skin muscle in the hamster.

Since the beginning of this century, the development of hemoglobin based oxygen carriers has been propagated for replacement of the oxygen carrying properties of red blood cells. A breakthrough has been impeded by problems related to the hemoglobin molecule itself and the ingredients of the solution, resulting in nephrotoxic side effects, limited intravascular half-life, vasoconstrictor potential and potential catalysis of oxygen free radical formation. Using intravital fluorescence microscopy and the dorsal skin fold chamber model of the awake Syrian golden hamster, the microcirculatory changes occurring in the thin striated skin muscle were quantitatively analyzed before and after administration of an ultrapurified polymerized bovine hemoglobin solution (U-PBHb) under the following experimental conditions: (1) Hypervolemic infusion of U-PBHb at approximately 10% of calculated blood volume, (2) isovolemic exchange transfusion with U-PBHBb by replacing approximately 50% of calculated blood volume and (3) severe hemorrhagic shock by acute bleeding of approximately 50% of calculated blood volume to a MAP of 35 +/- 5 mm Hg for 45 min followed by resuscitation with U-PBHb.

Role of Mac-1 and ICAM-1 in ischemia-reperfusion injury in a microcirculation model of BALB/C mice.

The leukocyte beta 2-integrin Mac-1 (CD11b/CD18) and its endothelial ligand intercellular adhesion molecule 1 (ICAM-1) are involved in leukocyte adhesion to and macromolecular leakage from postcapillary venules during inflammatory reactions. Both events are also encountered after ischemia-reperfusion of striated muscle, suggesting a central role of both adhesion proteins in reperfusion injury. Using intravital fluorescence microscopy and a microcirculation model in awake BALB/C mice, we investigated the effects of monoclonal antibodies (MAb) and Fab fragments to Mac-1 and MAb to ICAM-1 on leukocyte-endothelium interaction and macromolecular leakage of fluorescein isothiocyanate-dextran (1.

Leukocyte rolling in venules of striated muscle and skin is mediated by P-selectin, not by L-selectin.

Leukocyte rolling in post-capillary venules is mediated by adhesion molecules of the selectin family expressed on both leukocytes (L-selectin) and endothelial cells (E- and P-selectin). With the use of intravital fluorescence microscopy, the effects of antibodies against these selectins were analyzed in the skinfold chamber model of BALB/c mice and the ear model of homozygous hairless mice (hr/hr) that permit chronic observation of striated muscle and skin microcirculation in awake animals, respectively. Mice were injected intravenously with monoclonal antibodies (MAb) to murine L-selectin and E-selectin and affinity-purified polyclonal antibodies to P-selectin.

Diaspirin crosslinked hemoglobin: evaluation of effects on the microcirculation of striated muscle.

Hemoglobin-based oxygen carriers such as diaspirin-crosslinked hemoglobin (DCLHb) have been proposed for blood substitution due to their plasma expansion and oxygen transport capacity. This study investigates the effects of DCLHb on the microcirculation of striated muscle after moderate topload infusion and isovolemic exchange transfusion in awake hamsters. The skinfold chamber model in hamsters and intravital fluorescence microscopy were used for analysis of vessel diameter, red blood cell velocity (RBCV), leukocyte sticking to the microvascular endothelium, and macromolecular leakage in striated skin muscle.