Development of a new wound dressing with antimicrobial delivery capability

A bilaminar wound dressing composed of an outer membrane and an inner three-dimensional matrix of a fabric or a sponge may be considered to constitute an ideal structure that promotes wound healing: the outer membrane prevents body fluid loss, controls water evaporation, and protects the wound surface from bacterial invasion, and the inner matrix encourages adherence by tissue growth into the matrix. Using this concept, we developed a biosynthetic wound dressing with a drug delivery capability. This medicated wound dressing is composed of a spongy sheet of a chitosane derivative and collagen mixture that is laminated to an antimicrobial-impregnated polyurethane membrane. In this study, a gentamycin sulfate-impregnated wound dressing was prepared and evaluated. The antimicrobial efficacy of this wound dressing was examined on an agar plate seeded with Pseudomonas aeruginosa. Also, the cytotoxicity of an antimicrobial released from this wound dressing was examined in an in vitro system with cultured skin substitutes. Both in vitro tests have shown that this wound dressing is capable of suppressing bacterial growth and minimizing cellular damage. In addition, in the treatment of wounds inflicted on rats and rabbits, this wound dressing was shown to be efficacious in covering full-thickness and split-thickness skin defects. Finally, the efficacy of this wound dressing was evaluated in a nonrandomized open-label study of 31 clinical cases. In 31 cases treated with this wound dressing, good or excellent wound healing was achieved.     

Teaching nurses about neuromotor development: an evaluative study.

A neuromotor screening tool, The Chandler Movement Assessment of Infants Screening Test (CMAI-ST), was selected to teach nurses who care for premature infants about neuromotor development. After training with the CMAI-ST, the nurses were more adept at recognizing major components of neuromotor development.     

Long-lasting effect of ceruletide on dyskinesia and monoaminergic neuronal pathways in rats treated with iminodipropionitrile

In a model of dyskinesia induced by the administration of iminodipropionitrile (IDPN) in the rat, we evaluated the effects of ceruletide, an analogue of cholecystokinin, on behavioral abnormalities and monoaminergic neuronal function. Vertical head twitching in the IDPN-treated animals was inhibited for over 5 h following a single subcutaneous dose of 160 micrograms/kg ceruletide. In animals dosed daily for 2 or 3 days, the number of head twitches at 24 h after the last dose was about one-third of the number before treatment. After repeated daily doses of ceruletide for 6 days, the number of head twitches was reduced to low levels and remained significantly below pretreatment levels until the 4th posttreatment day. These results indicate that the inhibition of dyskinesia by ceruletide was long-lasting. Assays of monoaminergic neurotransmitters and their metabolites in various brain regions indicate that an imbalance between dopaminergic and serotonergic neuronal systems plays a major role in the pathogenesis of the IDPN-induced dyskinesia, i.e. the ratio of (DOPAC+HVA)/5-HIAA was significantly greater in the striatum but significantly smaller in the hippocampus of the IDPN-treated vs normal animals. This initially abnormal ratio of (DOPAC+HVA)/5-HIAA in the striatum and hippocampus of IDPN-treated animals returned to normal following treatment with ceruletide, corresponding with the reduction of the head twitching. The alterations in monoaminergic neuronal function induced by repeated administration of ceruletide persisted for at least 3 days, even though its plasma half-life is several minutes. Ceruletide also exerted a marked effect on monoaminergic neuronal function in the IDPN-treated rats, in contrast to only a slight effect in normal animals.(ABSTRACT TRUNCATED AT 250 WORDS)     

Gorog Thrombosis Test: analysis of factors influencing occlusive thrombus formation.

We used the Gorog Thrombosis Test to analyze the factors influencing the occlusion time, which represents platelet activation and subsequent occlusive thrombus formation, in 132 healthy Japanese volunteers (116 men, 16 women; mean age, 45.0 +/- 12.0 years). The Gorog Thrombosis Test was designed to evaluate platelet aggregation and thrombolytic activity under a high shear stress condition (175 dynes/cm) in a native blood sample in vitro. The mean +/- SD occlusion time was 154.8 +/- 64.7 s (men, 153.4 +/- 64.2 s and women, 165.4 +/- 56.5 s). The occlusion time was inversely correlated with von Willebrand factor ristocetin cofactor activity (VWF:Rco) (r = -0.242, P = 0.0055) and von Willebrand factor antigen (r = -0.230, P = 0.0080). The mean occlusion time in the group with VWF:Rco of at least 170% (137 s) was significantly shorter than that in the group with VWF:Rco less than 170% (156 s, P < 0.05). Platelet counts, other coagulation markers and smoking showed no significant correlations with occlusion time. Red blood cells (r = -0.177, P = 0.0365), hemoglobin (r = -0.191, P = 0.0245) and hematocrit (r = -0.182, P = 0.0329) also showed inverse correlations with the occlusion time. This report is the first to clearly demonstrate the role of von Willebrand factor in the formation of occlusive thrombi in the Gorog Thrombosis Test.     

Climbing exercise increases bone mass and trabecular bone turnover through transient regulation of marrow osteogenic and osteoclastogenic potentials in mice.

To investigate the relationship between the effects of bone turnover and bone marrow cell development in bone cells, we developed a mouse voluntary climbing exercise model. Climbing exercise increased bone volume and transient osteogenic potential of bone marrow. This model would be suitable for investigating the mechanistic roles of mechanical loading. INTRODUCTION: The relationship between bone mass gain and local bone formation and resorption in mechanically loaded bone is not well understood. MATERIALS AND METHODS: Sixty-five C57BL/6J mice, 8 weeks of age, were assigned to five groups: a baseline control and two groups each of ground control and climbing exercise mice for 2 and 4 weeks. Mice were housed in a 100-cm tower and had to climb toward a bottle placed at the top to drink water. RESULTS: Compared with the ground control, bone mineral density of the left femur increased in the climbing mice at 4 weeks. At 2 and 4 weeks, bone formation rate (BFR/BS) of periosteal surface, the cross-sectional area, and moment of inertia were increased in the climbing mice, whereas BFR/BS and eroded surface (ES/BS) of endosteal surface did not differ. The trabecular bone volume (BV/TV) of the proximal tibia increased in climbing mice, and osteoclast surface (Oc.S/BS) and osteoclast number decreased at 2 weeks. At 4 weeks, there were increases in BV/TV and parameters of bone formation, including mineralized surface, mineral apposition rate, and bone formation rate. In marrow cell cultures from the tibia, the number of alkaline phosphatase+ colony forming units-fibroblastic and the area of mineralized nodule formation in climbing mice were increased, and the number of osteoclast-like TRACP+ multinucleated cells was lower at 2 weeks. At 4 weeks, these parameters recovered to the levels of the ground controls. CONCLUSION: Our results indicate that climbing increased trabecular bone volume and reduced bone resorption, with a subsequent increase in bone formation. Intermittent climbing downregulates marrow osteoclastogenic cells and upregulates osteogenic cells initially, but further exercise seemed to desensitize them. Cortical envelopes were enlarged earlier, but the response seems to differ from trabecular bone.     

Rapid monitoring of changes in water diffusion coefficients during reversible ischemia in cat and rat brain

Changes in the diffusion constant of water during reversible brain ischemia and cardiac arrest were monitored with a 10-s time resolution. Results (five cats, three rats) indicate that these changes are reversible and that the bulk of the changes are not caused by temperature or motion related to brain pulsations and blood flow. The rapid time course of the changes corresponds to the known time course for changes in energy state, signal transduction, and ionic homeostasis.     

Depressed convulsions by diazepam and its effects on brain monoamines and amino acids in E1 mice

The effect of diazepam on inbred mutant E1 mice, which develop convulsive seizures after repeated sessions of being tossed up, was examined. Acute administration of diazepam (32 mg/kg, i.p.) completely inhibited the convulsions. At that time, the dopamine level was increased in the cortex and hippocampus, and the norepinephrine level in the cerebellum was decreased. 5-Hydroxytryptamine levels were not changed. As for amino acids, the glutamine level increased and the levels of GABA, glutamic acid, aspartic acid, alanine and other amino acids were not changed.     

Possible role of cytomegalovirus in the pathogenesis of inflammatory aortic diseases: a preliminary report.

To search for possible evidence of a relationship between human cytomegalovirus and aortic diseases, we examined 41 aortic lesions excised at surgery and 16 aortic tissues obtained at autopsy for the presence of cytomegalovirus DNA, by use of polymerase chain reaction. Cytomegalovirus DNA was present in seven (88%) of eight lesions of inflammatory aortic diseases with periaortic fibrosis, five of six inflammatory aneurysms, and all of two aortic occlusive lesions with inflammation. Cytomegalovirus DNA was detected in 20 (61%) of 33 atherosclerotic aneurysms, whereas it was detected in only five (31%) of 16 autopsy samples that showed neither inflammation nor atherosclerosis. Thus the possibility that cytomegalovirus may play a role in the pathogenesis of inflammatory aortic diseases warrants further attention.