A 71-year-old male patient with severe stenosis of the right common carotid artery and internal carotid artery underwent aortography+cerebral arteriography+right internal carotid artery stenting under local anesthesia with contrast medium iodixanol injection. Head CT before operation showed no obvious abnormality. Ten hours after the operation, the patient developed neurological symptoms such as fever, drowsiness, choking in drinking water, incomplete motor aphasia, decrease of muscle strength and tension of left limb, convulsions, etc. Brain magnetic resonance imaging (MRI) showed increased signal intensity in the right cerebral sulcus and sulcus shallower. Contrast-induced encephalopathy caused by iodixanol was considered. After 3 days of symptomatic treatments with rehydration, glucocorticoid, and mannitol, the patient′s symptoms were improved. Brain MRI showed that the hyperintensity of right cerebral cortex decreased and the sulcus gradually returned to normal.

A 71-year-old male patient with severe stenosis of the right common carotid artery and internal carotid artery underwent aortography+cerebral arteriography+right internal carotid artery stenting under local anesthesia with contrast medium iodixanol injection. Head CT before operation showed no obvious abnormality. Ten hours after the operation, the patient developed neurological symptoms such as fever, drowsiness, choking in drinking water, incomplete motor aphasia, decrease of muscle strength and tension of left limb, convulsions, etc. Brain magnetic resonance imaging (MRI) showed increased signal intensity in the right cerebral sulcus and sulcus shallower. Contrast-induced encephalopathy caused by iodixanol was considered. After 3 days of symptomatic treatments with rehydration, glucocorticoid, and mannitol, the patient′s symptoms were improved. Brain MRI showed that the hyperintensity of right cerebral cortex decreased and the sulcus gradually returned to normal.

Objective To investigate the feasibility of urethral reconstruction by using stretched electrospun silk fibroin matrices.Methods Stretched electrospun silk fibroin matrix was prepared,and the structure of the material was assessed by electron microscopy.Canine urothelial cells were isolated,expanded and seeded onto the material for 1 week to obtain a tissue-engineered graft.The tissue-engineered graft was assessed using HE staining and electron microscopy scanning.A dorsal urethral mucosa defect was created in 9 female beagle dogs.In the experimental group,tissue-engineered mucosa was used to repair urethral mucosa defects in 6 dogs.No substitute was used in the 3 dogs of the control group.Retrograde urethrography was performed at 1,2 and 6 months after grafting.The urethral grafts were analyzed grossly and histologically.Results Electron microscopy scanning revealed that the material had a 3 dimensional porous structure.Urothelial cells grew on the material and showed good biocompatibility with the stretched silk fibroin matrices.Canines implanted with tissue-engineered mucosa voided without difficulty.Retrograde urethrography revealed no signs of stricture,and histological staining showed gradual epithelial cell development and stratified epithelial layers at 1,2 and 6 months.The canines in the control group showed difficulty in voiding.Retrograde urethrography showed urethral stricture,and histological staining showed that no or only one layer of epithelial cells developed.A severe inflammatory reaction was also observed in the control group.Conclusion Stretched electrospun silk fibroin matrices have good biocompatibility with urothelial cells,and could be a potential material for urethral reconstruction.

OBJECTIVETo evaluate the direct effects of dobutamine as compared to adenosine on the coronary microcirculation in both normal and stenotic segments using myocardial contrast echocardiography (MCE).

METHODSLeft anterior descending (LAD) coronary artery stenosis, which was not flow limiting at rest, was established in 9 dogs. At the baseline and during intracoronary infusion of dobutamine (2 mg.kg(-1).min(-1)) and adenosine (5 mg.kg(-1).min(-1)), the radiolabeled microsphere (RM)-derived myocardial blood flow (MBF) were determined, and the double product (DP) and myocardial vascular resistance (MVR) were calculated. MCE was performed to determine the myocardial blood volume (MBV, represented by A) and microbubble velocity (beta).

RESULTSAs compared to the baseline level, the MBF increased and MVR decreased significantly in both the normal and abnormal beds during infusion of both drugs (P<0.05). In the normal bed, adenosine had no effect on MBV, the decrease in MVR was the result of decreased arteriolar (plus venular) resistance, and the increase in MBF was predominately due to the increase in b (deltabeta/ deltaA=13.6). Dobutamine caused a 28% increase in MBV, responsible for 32% of the decrease in the total MVR, but the increase in MBF arose mainly from the increase in b (deltabeta/deltaA=5.9). In the abnormal bed, both the drugs caused a similar increase in MBF entirely by increasing b, and 14% and 15% of the increases in capillary resistance were associated with the capillary derecruitment during administration of dobutamine and adenosine, respectively.

CONCLUSIONThe direct effects of intracoronary dobutamine infusion on the coronary microcirculation are similar to that of adenosine, and the increase in MBF occurs mostly as the result of increased myocardial blood velocity.

Adenosine ; pharmacology ; Adrenergic beta-Agonists ; pharmacology ; Animals ; Blood Flow Velocity ; drug effects ; Coronary Circulation ; drug effects ; Coronary Stenosis ; diagnostic imaging ; Coronary Vessels ; diagnostic imaging ; Dobutamine ; pharmacology ; Dogs ; Echocardiography ; methods ; Microcirculation ; drug effects ; Vasodilator Agents ; pharmacology