The blood compatibility of chitosan and N-acylchitosans

A segment of silk polyfilament suture [No. 2-0(USP)], ca. 10 cm long, was coated with a thin membrane (2-6 micron) of chitosan, N-acetylchitosan, or N-hexanoylchitosan. The suture was directly inserted into the lumen of dog's peripheral veins. The in vivo blood compatibility of these membranes was macroscopically determined from the blood coagulum formed on the membrane surface at 2 h. An intense thick blood coagulum formed on the chitosan membrane surface and a thin blood coagulum formed on N-acetylchitosan membrane surface, but no blood coagulum formed on N-hexanoylchitosan membrane surface.     

Effect of bronchodilation on the deposition and clearance of radioaerosol in bronchial asthma in remission

Radioaerosol inhalation lung cine-scintigraphy and lung function tests were performed on ten patients with bronchial asthma in remission before and after inhalation of salbutamol following intravenously administered aminophylline. Radioaerosol inhalation lung cine-scintigraphy was very useful in revealing the changes not only in the deposition patterns of inhaled aerosol in the lungs but also in the dynamic transport of mucus on the airways. The bronchodilating effect of the combined treatment was significant; the inhaled aerosol deposited more homogeneously and less centrally in the lungs, the "penetration index" and the alveolar deposition ratio (ALDR) increased from 31 +/- 3 to 49 +/- 7%, and from 29 +/- 2% to 39 +/- 1%, respectively, while the airway deposition ratio (ADR) decreased from 72 +/- 2 to 61 +/- 1% immediately after the treatment. Lung function data including FVC, FEV 1.0, FEV 1.0%, MMF, V50 and Vp significantly improved after the treatment. There was, however, little visual or quantitative improvement in mucociliary clearance after the treatment.     

Feasibility of a self‐assembling peptide hydrogel scaffold for meniscal defect: An in vivo study in a rabbit model

The inner avascular zone of the meniscus has limited healing capacity as the area is poorly vascularized. Although peptide hydrogels have been reported to regenerate bone and cartilage, their effect on meniscus regeneration remains unknown. We tested whether the self‐assembling peptide hydrogel scaffold KI24RGDS stays in the meniscal lesion and facilitates meniscal repair and regeneration in an induced rabbit meniscal defect model. Full‐thickness (2.0 mm diameter) cylindrical defects were introduced into the inner avascular zones of the anterior portions of the medial menisci of rabbit knees (n = 40). Right knee defects were left empty (control group) while the left knee defects were transplanted with peptide hydrogel (KI24RGDS group). Macroscopic meniscus scores were significantly higher in the KI24RGDS group than in the control group at 2, 4, and 8 weeks after surgery. Histological examinations including quantitative and qualitative scores indicated that compared with the control group, the reparative tissue in the meniscus was significantly enhanced in the KI24RGDS group at 2, 4, 8, and 12 weeks after surgery. Immunohistochemical staining showed that the reparative tissue induced by KI24RGDS at 12 weeks postimplantation was positive for Type I and II collagen. KI24RGDS is highly biocompatible and biodegradable, with strong stiffness, and a three dimensional structure mimicking native extracellular matrix and RGDS sequences that enhance cell adhesion and proliferation. This in vivo study demonstrated that KI24RGDS remained in the meniscal lesion and facilitated the repair and regeneration in a rabbit meniscal defect model.     

High flow medullary venous malformation with aneurysm on the proximal artery--a case report

Medullary Venous Malformation with an aneurysm is uncommon and only 4 cases have been reported in previous papers. We reported a case of a medullary venous malformation (MVM) of the frontal lobe with an aneurysm on its proximal artery. A 48 year old female with numbness of right fingers visited our hospital. On the CT scan, an abnormal enhanced area was found inside the left frontal lobe. The left carotid angiography showed both of an aneurysm around A com A in early arterial phase, and "MVM with early blush" in capillary-early venous phase. MRI showed linear signal void crossing the cortex to join paraventricular low intensity area (LIA) with slight cortical atrophy on sagittal slice. The CBF study by Xe-SPECT proved a high flow lesion, with mean CBF 69 (left), 59 (right) mg/100 g brain/min, Protective operation only for aneurysm was performed. The MVM in our case was proved to be a "high flow-low resistance system" by CBF study, although MVM has been considered a "low flow system". Reviewing papers, there were 3 cases of "high flow MVMs" confirmed by the measurement of CBF, all of them were large sized (greater than 4 cm) and with early blush angiographically. We conclude that large sized MVM with early blush needs hemodynamic inspection and special care to prevent "high flow MVMs" from hemorrhage and the steal.     

Intramural duodenal hematoma: a case report

A 55-year-old male patient with acute onset of abdominal pain was examined. He had no apparent history of abdominal trauma or bleeding tendency. MRI showed three layered architecture, so-called "ring sign" distinctive of hematoma. MRI seemed to be very useful in non-invasively diagnosing intramural duodenal hematoma.     

Serum cathepsin-B levels and urinary-excretion of cathepsin-B in the patients with colorectal-cancer - possible indicators for tumor malignancy

Serum cathepsin B levels and urinary excretion of cathepsin B in patients with colorectal cancers were significantly higher than those in the control non-cancer patients. Moreover, cancer tissue cathepsin B content was significantly higher than that in the normal tissue. After radical curative operations for colorectal cancers, both the serum cathepsin B levels and urinary excretion of cathepsin B were restored to the control values. These results suggest a possible role of lysosomal enzyme, cathepsin B, in the pathogenesis of tumor growth, and also suggest that these parameters might be possible indicators for tumor malignancy.     

Pupillary responses in normal subjects following auditory stimulation

To clarify pupillary responses of humans following auditory stimuli, we studied both eyes of 61 normal subjects using a computed pupillograph. Unilateral auditory stimulation elicited pupillary dilatation in all cases. Pupillary responses were classified according to duration as being either “long” or “short”. The duration of dilatation was 1530±320 ms (mean±SD) in the longlasting group (n=45) and 850±250 ms in the short-lasting group (n=16). The latency time for dilatation was 460±80 ms. Both eyes of each subject showed the same response. Two drops of 10% guanethidine, a sympathetic blocking agent, were applied to one eye of 3 subjects. Although the early phase of dilatation was barely affected, the late phase was inhibited, as seen in long-lasting dilatation. The short-lasting response was unaffected. We conclude that the long-lasting response consists of an early pupillary dilatation due to inhibition of parasympathetic nervous activity and a late dilatation due to excitation of sympathetic activity. The short-lasting response is produced only by inhibition of the parasympathetic component.