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1.
A 54-year-old female presented with subarachnoid hemorrhage due to rupture of a small middle cerebral artery aneurysm, found to be thrombosed at surgery and not visualized on the preoperative angiograms. One major branch of the middle cerebral artery was found to be occluded near the trifurcation. The lumen of the branch proximal to the occlusion had appeared as the aneurysmal opacification on the preoperative angiograms.  相似文献   
2.
Cerebral amyloid angiopathy (CAA) is an important cause of intracerebral hemorrhage and ischemic cerebrovascular disease in some normotensive elderly patients. The diagnosis is made by proof of amyloid deposition in the vessel wall. A case of recurrent and multiple intracerebral hemorrhages due to cerebral amyloid angiopathy after head injury is reported. A 74-year-old female was referred to our hospital because of head injury. CT scan showed traumatic subarachnoid hemorrhage and intraventricular hematoma. Her consciousness was clear but slight disorientation was recognized. Conservative therapy was performed. During the course subcortical hemorrhages occurred five times and during the second one, right frontal and right parietal hemorrhages occurred simultaneously. Her consciousness deteriorated. The second subcortical hemorrhage was especially complicated by a ventriculoperitoneal shunt operation. A biopsy of the cortex was performed and pathological examination revealed amyloid deposition in the walls of small pial and cortical vessels. Occasional duplicated wall, obliterative intimal proliferation and disappearance of elastic lamina were recognized. The patient sank into a vegetative state due to recurrent and multiple hemorrhages. CAA results in two possibilities, hemorrhage and ischemic cerebrovascular disease. When lobar or subcortical hemorrhage is encountered in a normotensive elderly patient, the possibility of a CAA-related hemorrhage should be considered. The author carefully emphasizes that there is indication for neurosurgical treatment in CAA patients and proposes that therapy for ischemic cerebrovascular disease should be given special attention.  相似文献   
3.
Previously, we demonstrated that human peripheral T lymphocytes revealed early apoptotic changes (annexin V-positive) and late apoptotic changes (propidium iodide-positive), at 13 and 24 h, respectively, after irradiation of 5 Gy. Changes in mitochondrial membrane potential were observed at 10 h after irradiation of 5 Gy. Subsequently, mitochondrial cytochrome c-release was confirmed. In order to elucidate the mechanism which acts prior to the mitochondrial membrane potential changes, we examined in the previous study the radiation dose and the timing of oxidative DNA damage induced in human peripheral T lymphocytes following 10 MV X-ray irradiation. As a result, the production of 8-oxoguanine, i.e., the product of oxidative DNA damage, was clearly identified starting at 10, 6, and 3 h, after 2, 5, and 20 Gy of irradiation, respectively. Therefore, we examined in the present study reactive oxygen species (ROS) formation in T lymphocytes following 5 Gy of irradiation. Using a CCD camera system, we monitored fluorescence in T lymphocytes loaded with the succinimidyl ester of dichlorodihydrofluorescein diacetate (H2DCFDA), which is non-fluorescent until oxidized by ROS. We found that ROS formation occurred immediately after irradiation, continued for several hours, and resulted in oxidative DNA damage. Therefore, the origin of hyper-radiosensitivity of T lymphocytes seemed to be the high production of ROS in the mitochondrial DNA following irradiation.  相似文献   
4.
In our previous study, we examined reactive oxygen species (ROS) formation in T lymphocytes following 5 Gy irradiation. We found that ROS formation occurred immediately after irradiation, continued for several hours, and resulted in oxidative DNA damage. Therefore, the origin of the hyper-radiosensitivity of T lymphocytes seemed to be the high production of ROS in the mitochondrial DNA following irradiation. In the succeeding study, we examined radiation-induced ROS formation, oxidative DNA damage, early apoptotic changes, and mitochondrial membrane dysfunction in the human osteosarcoma cell line HS-Os-1. We found that ROS formation and oxidative DNA damage were actually scarcely seen after irradiation of up to 30 Gy in these cells, that mitochondrial membrane potential was preserved, and that apoptotic changes were not demonstrated despite the relatively high-dose irradiation of 30 Gy. In the present study, we examined the immunocytochemical characteristics of the apoptotic-resistance of the HS-Os-1 cell line against irradiation in order to clarify its possible implications regarding radiosensitivity. The results showed that these cells lack P53 and Bax protein expression, and strong peroxidase activity was confirmed in the nuclei of the cells. Moreover, SODII (manganese superoxide dismutase II) protein expression was gradually increased in spite of irradiation of up to 30 Gy. Therefore, it is concluded that HS-Os-1 cells are originally apoptotic-resistant and that the cells possess a strong ability to scavenge for free radicals. To convert these cells to a state of apoptotic-susceptibility, a powerful oxidant such as hydrogen peroxide might exert such an effect in terms of the production of hydroxyl radicals in lysosomes in the cells as shown in our previous studies. The origin of the radioresistance of the human osteosarcoma cell line HS-Os-1 is considered to to be low degree of ROS formation following irradiation, reflecting the strong scavenging ability of these cells for free radicals including hydroxyl radicals.  相似文献   
5.
Allosensitization represents a major barrier to heart transplantation (HTx). We assessed the efficacy and safety of complement inhibition at transplant in highly sensitized heart transplant recipients. We performed a single-center, single-arm, open-label trial (NCT02013037). Patients with panel reactive antibodies (PRA) ≥70% and pre–formed donor-specific antibodies (DSA) were eligible. In addition to standard of care, patients received nine infusions of eculizumab during the first 2 months posttransplant. The primary composite endpoint was antibody-mediated rejection (AMR) ≥pAMR2 and/or left ventricular dysfunction during the first year. Secondary endpoints included hemodynamic compromise, allograft rejection, and patient survival. Twenty patients were included. Median cPRA and mean fluorescence intensity of immunodominant DSA were 95% (90%–97%) and 6250 (5000–10 000), respectively. Retrospective B cell and T cell flow crossmatches were positive in 14 and 11 patients, respectively. The primary endpoint occurred in four patients (20%). Survival at 1 year was 90% with no deaths resulting from AMR. In a prespecified analysis comparing treated patients to matched control patients, we observed a dramatic reduction in the risk of biopsy-proven AMR in patients treated with eculizumab (HR = 0.36, 95% CI = 0.14–0.95, p = .032). Our findings support the prophylactic use of complement inhibition for heart transplantation at high immunological risk. ClinincalTrials.gov, NCT02013037.  相似文献   
6.

Purpose

To determine the extent of enhanced blockade by the combined use of epidural fentanyl and mepivacaine. We compared the onset of hypoalgesia, analgesia and the threshold of pressure pain.

Methods

Thirty patients were randomly divided into three groups. The fentanyl group received 10 ml saline containing 0.1 mg fentanyl, mepivacaine group received 10 ml mepivacaine 1% and a mixed group received 10 ml mepivacaine 1% with 0.1 mg fentanyl. All solutions, without epinephrine, were injected through an epidural catheter at T5–6 to T6–7. The change in sensation, loss of pin-prick and pain threshold sensation, measured by pressure algometer, were assessed at 2.5-min intervals for 15 min at the T4 dermatome. Spread of analgesia was determined at 15 min.

Results

Loss of pinprick was more rapid in the mixed, 11.0 ± 2.7 (SD) min, than in the mepivacaine group, 15.0 ± 2.9 min, (P < 0.05), although there was no difference in change of sensation. Pressure pain threshold increased with time in the mepivacaine (P < 0.05) and mixed (P < 0.05) groups. It was higher in the mixed than in the fentanyl and mepivacaine groups at 5, 7.5 and 10 min (P < 0.05). The lower level of analgesia was lower in the mixed than in the mepivacaine groups (P < 0.05). Blood pressure was unchanged in the three groups, but heart rate decreased at 7.5, 10, 12.5, and 15 min in the mepivacaine and mixed groups (P < 0.05).

Conclusions

The addition of fentanyl to mepivacaine accelerates the onset of analgesia and enhances the analgesic effect of epidural block.  相似文献   
7.
With the purpose of obtaining an accurate definition of coronary arteries anatomy in complete transposition of the great arteries (concordant atrio-ventricular connection and discordant ventriculo-arterial connection), we performed a new angiographic technique in 14 patients with d-transposition of the great arteries and 1 patient with double-outlet right ventricle. This technique consists of using a balloon catheter with the frontal X ray tube cine-angiographic camera in caudal angulation (about 45 degrees), with balloon occlusion of the ascending aorta during the injection of the contrast medium. The results were compared with echocardiograms and surgical results. In all our cases, except 2, the technique gave us a very clear definition of the coronary anatomy and we were able to define the origin and course of the coronary arteries without difficulty. In the most common coronary artery pattern, the left coronary artery arose from sinus #1 (left aortic sinus) and gave origin to the anterior descending and left circumflex arteries, while the right coronary artery arose from aortic sinus #2 (right aortic sinus). In our series, the coronary arteries always originated from one or both facing sinuses of the aorta and the angiographic correlation with the surgical reports was accurate in all the cases. The anatomical and angiographic findings of this series are discussed. In conclusion, we find the aortogram with caudal angulation a very useful technique to improve the visualization of coronary anatomy in d-transposition of the great arteries, which has surgical significance in those cases which are candidates for anatomical correction.  相似文献   
8.
Postoperative myocardial perfusion and function were evaluated using thallium-201 myocardial imaging and technetium-99m cardiac pool imaging in five patients with an anomalous left coronary artery arising from the pulmonary artery. The patients underwent reimplantation of the left coronary artery at an age ranging from 10 months to 13 years. Postoperative electrocardiographic and radionuclide studies were performed both at rest and during stress 1 to 4 years after the operation. Electrocardiograms which were abnormal preoperatively returned to normal after surgery except that the T wave in lead aVL remained negative. Postoperatively, left ventricular ejection fraction measured by technetium-99m cardiac pool imaging was normal in all patients. Postoperative thallium-201 myocardial imaging, however, showed a perfusion defect with incomplete redistribution at the high-lateral or antero-lateral segment in all patients after a stress test. These data suggest that although myocardial ischaemic change decreases and global cardiac function improves after establishment of a dual coronary artery system, severe myocardial damage remains at the high-lateral or antero-lateral segment.  相似文献   
9.
We successfully treated a case of mitral regurgitation due to chest trauma in Barlow's disease. A 71‐year‐old man was admitted with severe mitral regurgitation after blunt compression of the chest by a heavy object 5 months earlier. Preoperative examination revealed wide chordae tendineae rupture and myxomatous changes to the bileaflets. Neo‐chordae reconstruction of the anterior mitral leaflet using loop technique, triangular resection of the posterior mitral leaflet, and ring annuloplasty was performed via surgical robot. Robotic mitral valve plasty for severe mitral regurgitation due to chest trauma in Barlow's disease was achieved safely with good clinical and excellent cosmetic results.  相似文献   
10.
Echocardiographic left ventricular (LV) dimensions in patients with complete transposition of the great arteries (TGA's) were measured before and after the Jatene procedure and/or pulmonary artery banding (PAB). The LV posterior wall thickness at end-diastole (LVPWTD) increased from 3.5 +/- 0.4 to 4.9 +/- 0.9 mm (mean +/- 1SD) (p less than 0.01) after PAB, but it did not show a significant change following the Jatene procedure (from 4.5 +/- 1.0 to 5.3 +/- 0.8 mm). The LV end-diastolic internal dimension (LVIDD) increased from 17.7 +/- 4.0 to 22.6 +/- 6.5 mm after PAB (p less than 0.01), but remained unchanged after the Jatene procedure (from 24.5 +/- 5.0 to 25.0 +/- 3.0 mm). The LV shortening fraction (LVSF) decreased from 0.62 +/- 0.10 to 0.47 +/- 0.14 after PAB (p less than 0.01), but remained unchanged after the Jatene procedure (0.40 +/- 0.10 to 0.37 +/- 0.10). the a/b ratio at end-systole: (a/b)s, which indicates the flatness of the LV configuration, increased from 0.27 +/- 0.14 to 0.60 +/- 0.21 after PAB (p less than 0.01) and from 0.61 +/- 0.13 to 0.74 +/- 0.17 after the Jatene procedure (p less than 0.01). The data obtained became stable 1 month after operation. One patient died of low cardiac output with no evidence of myocardial infarction after the Jatene procedure. In this patient, LVPWTD was 5.7 mm, LVIDD was 26 mm, LVSF was 0.71 and the (a/b)s ratio was 0.55.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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