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C-complex asteroids, rich in carbonaceous materials, are potential sources of Earth's volatile inventories. They are spectrally dark resembling primitive carbonaceous meteorites, and thus, C-complex asteroids are thought to be potential parent bodies of carbonaceous meteorites. However, the substantial number of C-complex asteroids exhibits surface spectra with weaker hydroxyl absorption than water-rich carbonaceous meteorites. Rather, they best correspond to meteorites showing evidence for dehydration, commonly attributed to impact heating. Here, we report an old radiometric age of 4564.7 million years ago for Ca-carbonates from the Jbilet Winselwan meteorite analogous to dehydrated C-complex asteroids. The carbonates are enclosed by a high-temperature polymorph of Ca-sulfates, suggesting thermal metamorphism at >300{\deg}C subsequently after aqueous alteration. This old age indicates the early onset of aqueous alteration and subsequent thermal metamorphism driven by the decay of short-lived radionuclides rather than impact heating. The breakup of original asteroids internally heated by radioactivity should result in asteroid families predominantly consisting of thermally metamorphosed materials. This explains the common occurrence of dehydrated C-complex asteroids., Comment: 19 pages, 8 figures, 2 tables

We report a case of liver abscess and portal vein thrombosis, which occurred due to diverticulitis at the terminal ileum in a 59-year-old man. The patient underwent a barium fluoroscopic examination 1 month before presenting to our hospital. He also showed liver dysfunction due to thrombosis at the superior mesenteric and portal veins. His inflammation gradually subsided after the initiation of treatment, but the recovery was not sufficient. Thus, surgery was performed. The patient condition improved after surgery and he was discharged. Barium examinations are relatively safe, but can sometimes cause severe adverse effects in patients with certain risk factors, and an appropriate diagnosis and treatment are necessary when symptoms appear.

The Ninth Symposium on Polar Science/Ordinary sessions: [OA] Antarctic meteorites / Hayabusa, Wed. 5 Dec. / 2nd floor of the Research/Administration Building at the JAXA Sagamihara Campusat

症例は28歳，男性．2010年5月腹痛を主訴に，救急外来を受診．上腹部は硬く，腹膜刺激症状および貧血を認めた．CTにて胃癌および転移リンパ節の破裂が疑われ入院．内視鏡検査で胃角部から胃前庭部後壁に2型胃癌を認め，生検にて低分化腺癌，免疫染色α-fetoprotein（AFP）陽性．血清AFPは133.7ng/ml．術前のCT再検にて，上腸間膜静脈に腫瘍栓を疑う欠損像を認めた．胃全摘術，D2郭清，門脈腫瘍栓摘出術施行．病理組織検査では原病巣は低分化腺癌に一部hepatoid patternを含みAFP陽性，腫瘍栓でも同様の所見を認めた．T2(MP)N3aM1(OTH)H0 P0，stageIVの診断．術後1カ月よりS-1にて補助化学療法を開始．現在術後1年経過するが再発徴候はない．転移リンパ節破裂を契機に診断された門脈腫瘍栓を伴うAFP産生胃癌に対し，根治的手術を行ったまれな症例を報告する．

症例は88歳，女性．嚥下困難を主訴に来院した．上部消化管内視鏡では，胃上部の圧排像と幽門前庭部小彎に早期胃癌を認めた．上部消化管造影では，食道裂孔ヘルニアにより胃が縦隔内に挙上されており，縦隔内に腫瘤影が見られた．CTにて，縦隔内の胃壁から突出する14×10cm大の腫瘤を認め，食道裂孔ヘルニアにより縦隔内に挙上した胃壁から発生した粘膜下腫瘍と診断した．開腹して食道裂孔を開き，腫瘍と胃を腹腔内に引き戻し，胃全摘術を施行した．病理所見により幽門前庭部に早期胃癌を合併した胃原発GIST（gastrointestinal stromal tumor）と診断した．術後経過は良好であったが，術後11カ月で肝・縦隔・左胸腔内にGISTの再発を見たため，imatinibによる治療を開始した．食道裂孔ヘルニアを伴う縦隔腫瘍の診断においては，縦隔に移動した胃壁から発生したGISTの可能性も考慮すべきと考えられた．

A 79-year-old man with a cardiac pacemaker for bradycardia fell down and presented with sudden onset of right hemiplegia and aphasia. Initial computed tomography (CT) showed no cerebral infarction but angiography revealed occlusion of the left middle cerebral artery (MCA). Local intra-arterial thrombolysis with tissue plasminogen activator (tPA; tisokinase, 1,600,000 units) was performed 3 hours after the onset, and the MCA was partially recanalized. Further administration of tPA was suspended because of nosebleed. However, the patient’s neurological findings did not improve. His consciousness gradually deteriorated to coma and quadriplegia with dilation of the left pupil 2.5 hours after thrombolysis. CT disclosed marked mass effect with a left acute subdural hematoma and a small intracerebral hematoma in the left frontal lobe. He underwent urgent craniotomy and removal of the subdural hematoma. The subdural hematoma originated in a frontal cerebral contusion. He died of severe brain edema 2 days after surgery. Acute subdural hematoma is a very rare complication of intra-arterial thrombolysis. Presumably he had suffered head trauma at the first onset. Evidence of head trauma should be considered a contraindication for the use of thrombolytic agents in a patient with acute stroke.

症例は51歳女性. 2001年7月,喀血を主訴に当院呼吸器科受診,胸部レントゲン所見上,右下肺野に浸潤影を認めた.気管支鏡検査を施行したが,出血源の同定は不可能であった. 2002年2月,再び喀血したため,気管支鏡検査を再施行したが,出血に関して有意な所見はなかった. 2002年4月, 3度目の喀血があり,精査加療目的に当院呼吸器科入院となった.気管支動脈造影および肺動脈造影にて気管支動脈-肺動脈シャントが描出されたので,気管支動脈-肺動脈シャントに起因する喀血と診断,喀血のコントロールを目的に2002年6月3日,右肺底区域切除を施行した.術後病理診断は肺アスペルギルス症であった.術後経過は良好であり以降喀血はない.術前に肺アスペルギルス症とは診断しえなかったが,喀血に対して外科治療は有効であった.気管支動脈-肺動脈シャントと肺アスペルギルス症に関して若干の文献的考察を加えて報告する.

A 56-year-old man with ruptured right P2-P3 junction aneurysm and a 66-year-old man with ruptured left P2-P3 junction aneurysm of the posterior cerebral artery associated with acute-stage packed intraventricular hemorrhage. The aneurysms were successfully clipped through the transcortical transchoroidal fissure approach. This approach requires less retraction of the temporal lobe, provides a wider surgical field, and the P2 segment can be easily reached. The present approach is very useful for the treatment of ruptured aneurysms at the P2-P3 junction, in particular for acute stage surgery associated with packed intraventricular hemorrhage.

Object. The effects of the adenosine receptor antagonists theophylline (for A1 and A2) and ZM 241385 (for A2A) on hippocampal injury and Morris water maze (MWM) performance in rats were investigated following normoglycemic and hyperglycemic cerebral ischemia (induced by four vessel occlusion for 10 minutes). Methods. Theophylline (36 mg/kg), ZM 241385 (1 mg/kg), or an equivalent volume of saline was administered to rats intraperitoneally 30 minutes before ischemia was induced. Moderate hyperglycemia was achieved by intraperitoneal administration of D-glucose (3 g/kg, 15 minutes before induction of ischemia). Morris water maze trials were performed on the 6th, 7th, and 8th days after ischemic insult. After the conclusion of the performance tests, the rat brains were cut into 8-xm sections, stained with cresyl violet and acid fuchsin, and evaluated in a blinded fashion to determine the extent of injury. Theophylline worsened injury in the hippocampus following normoglycemic and hyperglycemic ischemia. Moreover, theophylline significantly (p < 0.05, six animals) worsened latency and learning index (LI) scores during the MWM trials in both normoglycemic and hyperglycemic animals. On the other hand, ZM 241385 had no effect on either ischemic injury or MWM performance in normoglycemic animals. In the animals in the hyperglycemic ischemia group, however, ZM 241385 significantly (p < 0.05, five animals) reduced injury in the CA1 (94.6 ± 1.7% compared with 79.2 ± 10.9%), CA3 (26 ± 12.5% compared with 11.2 ± 4.3%), and hilum (22.4 ± 8.1% compared with 11 ± 5.5%) regions. In addition, ZM 241385 significantly improved latency (52 ± 29.7 seconds compared with 24.8 ± 11.2 seconds, p < 0.05) and LI scores (203.2 ± 33.3 compared with 152.1 ± 31.8, p < 0.05) in the MWM trials. A statistically significant correlation was also found between hippocampal injury (CA1, CA3, and hilum) and MWM performance. Conclusions. The results of this study provide further evidence for a neuromodulatory role of adenosine during normoglycemic and hyperglycemic ischemia.

The viability of tumor cells in radionecrotic tissue after interstitial brachytherapy (BRTX) was evaluated using immunohistochemical markers of proliferative potential in primary and recurrent tumors. Tumor specimens from 30 patients with malignant gliomas (14 anaplastic astrocytomas, 16 glioblastomas) taken before and after BRTX were examined using MIB-1 monoclonal antibody. Histological examination of specimens obtained by craniotomy or stereotactic biopsy after BRTX revealed tumor recurrence in 18 patients and radionecrosis in 12 patients including two with pure radionecrosis and 10 with a mixture of both tumor and radionecrosis. The MIB-1 index of the tumors with radionecrosis was 7.6 +/- 5.5%, and that of the primary tumors was 17.0 +/- 11.2%, showing a significant difference (p < 0.05). There was no significant difference between the MIB-1 index of the primary tumors with local recurrence after BRTX and the primary tumors which underwent radionecrosis. Although morphologically viable tumor cells were found in the radionecrotic tissue, BRTX causes a reduction in the proliferative potential of these tumor cells.

A simple computed tomography- (CT) or magnetic resonance (MR) imaging-guided stereotactic method for guided microsurgical resection of either deep-seated gliomas or tumors adjacent to an eloquent area is described. The technique employs the Brown-Roberts-Wells stereotactic system and twist drills, 2.7 mm in diameter, for the stereotactic placement of 2.4 mm diameter scaled guidance catheters through the calvaria. In a patient with a deep-seated small glioma, less than 2 cm diameter, one catheter was implanted into the center of the enhanced mass through the cerebral cortex. In the other 14 patients, three to six catheters were used which made the tumor border clearer. After implantation of the guidance catheters, the stereotactic frame was removed and a standard open craniotomy performed. Target localization is not affected by brain movement, which is inevitable during open surgery. The tumor involved the frontal lobe in eight patients, the parietal lobe in two, and the thalamus in five. In all cases the lesion was quickly localized and radical removal was achieved. Neurological complications occurred in only one patient who suffered transient hemiparesis after the resection of a lesion in the pyramidal tract. The results demonstrate that microsurgery combined with CT- or MR imaging-guided stereotactic placement of guidance catheters is a new option for surgery of deep-seated gliomas or tumors adjacent to an eloquent area.

The effects of irradiation on a large volume of normal brain tissue as occurs in interstitial brachytherapy were investigated. Double iridium-192 seed assemblies were stereotactically implanted into the right centrum semiovale of eight adult Japanese monkeys (Macaca fuscata). The morphological changes induced in the normal brain tissue were evaluated with magnetic resonance (MR) imaging with and without gadolinium-diethylenetriaminepenta-acetic acid (Gd) enhancement at 2 days and 1, 3, and 6 months after the brachytherapy. After each MR imaging examination, randomly selected experimental animals were sacrificed to analyze the histological changes. The low intensity area seen inside the ring of contrast enhancement on the T1-weighted image with Gd enhancement was well correlated with histologically defined necrosis. The high intensity area seen outside the area showing contrast enhancement on the T2-weighted image was well correlated with an area of histological edema and demyelination. The sizes of the lesion and the high intensity area were maximum during the acute stage (2 days) following interstitial irradiation. This monkey model with MR imaging can be used to investigate the development of brain damage induced by interstitial irradiation. We further recommend careful monitoring to detect the development of brain edema during the acute stage after interstitial brachytherapy, especially when large tumors are treated.

The magnitude and time course of histological and neuroradiological changes due to interstitial hyperthermia in normal cerebral white matter were investigated in eight adult Japanese monkeys. A cooling system enveloping a 2450-MHz microwave antenna was inserted stereotactically into the brain under general anesthesia. A point located 5 mm away from the surface of the cooling system was used as the reference point (RP). Hyperthermia was given to maintain the RP at 43 degrees C for 60 minutes. Two animals were sacrificed under general anesthesia following the intravenous administration of Evans blue, immediately and 1, 3, and 7 days after treatment. After removing the brain, histological changes were investigated. Magnetic resonance (MR) imaging was performed at 1, 3, and 7 days after treatment. Evans blue extravasation was most prominent in the region heated to 43 degrees C or above immediately after treatment. MR imaging showed obvious enhancement in the region heated to 43 degrees C or above 1 day after treatment, related to the disruption of the blood-brain barrier (BBB) by hyperthermia. Three days after treatment, ring-like enhancement with a central low-intensity area was seen in the region heated to about 43 degrees C, caused by BBB disruption and slight neovascularization. One week after treatment, an enhanced ring was observed in the region heated to less then 43 degrees C which surrounded a low-intensity area. The enhancement seen 1 week after treatment was caused by prominent neovascularization. T2-weighted imaging showed a high-intensity area, caused by edema, most prominent 3 days after treatment. Thus chemotherapeutic agents should be given just before the end of hyperthermia.

A 79-year-old man with a cardiac pacemaker for bradycardia fell down and presented with sudden onset of right hemiplegia and aphasia. Initial computed tomography (CT) showed no cerebral infarction but angiography revealed occlusion of the left middle cerebral artery (MCA). Local intra-arterial thrombolysis with tissue plasminogen activator (tPA; tisokinase, 1,600,000 units) was performed 3 hours after the onset, and the MCA was partially recanalized. Further administration of tPA was suspended because of nosebleed. However, the patient's neurological findings did not improve. His consciousness gradually deteriorated to coma and quadriplegia with dilation of the left pupil 2.5 hours after thrombolysis. CT disclosed marked mass effect with a left acute subdural hematoma and a small intracerebral hematoma in the left frontal lobe. He underwent urgent craniotomy and removal of the subdural hematoma. The subdural hematoma originated in a frontal cerebral contusion. He died of severe brain edema 2 days after surgery. Acute subdural hematoma is a very rare complication of intra-arterial thrombolysis. Presumably he had suffered head trauma at the first onset. Evidence of head trauma should be considered a contraindication for the use of thrombolytic agents in a patient with acute stroke.

A 54-year-old man presented with unconsciousness. Computed tomography revealed acute subdural hematoma. Emergency evacuation of hematoma was performed showing any excessive tendency to bleed or difficulty to stop bleeding during the operation. However transfusion of fresh frozen plasma was needed to stop continuous bleeding from the surgical wound after the operation. The patient underwent craniotomy again 18 days after the operation because he suffered hemorrhagic infarction and recurrence of acute subdural hematoma. After the second operation, a coagulability examination revealed that his activated partial thromboplastin test was prolonged (74.5 seconds) and his plasma factor VIII level was 20% of normal, so he was diagnosed as having mild hemophilia A. Cranioplasty was accomplished with replacement therapy, and he was discharged with mild recent memory disturbance and homonymous hemianopsia.

Brainstem hemorrhage in descending transtentorial herniation is well known as Duret hemorrhage. However, CT or MRI rarely reveals Duret hemorrhage. The authors report a case of brainstem hemorrhage after craniotomy of spontaneous acute subdural hematoma. A 47-year-old man suffered sudden onset of severe headache and progressive consciousness disturbance. Initial CT scan demonstrated a right acute subdural hematoma and a marked shift of the midline structures to the left. Emergency craniotomy was performed but he remained comatose. CT scan after 8 days showed multiple petechial hemorrhages in the brainstem. We reported a rare case of Duret hemorrhage diagnosed by CT scan. Duret hemorrhage is almost fatal.

We investigated the effects of PD 81,723, an allosteric enhancer for the adenosine A(1) receptor subtype, on hippocampal injury and Morris water maze (MWM) performance following hyperglycemic cerebral ischemia and reperfusion (4-VO, 10 min) in the rat. PD 81,723 (3 or 10 mg/kg) or the equivalent volume of saline was administered intraperitoneally 30 min prior to ischemia. Moderate hyperglycemia was achieved by administration of D-glucose (3g/kg, i.p.) 15 min prior to induction of ischemia. Morris water maze trials were performed on the 6th, 7th, and 8th days after the ischemic insult. The rat brains were sectioned (8 microm), stained with cresyl violet/acid fuchsin, and evaluated for hippocampal ischemic injury by an experimenter blinded to the treatment conditions. At the higher dose, PD 81,723 (10 mg/kg) had no effect on hippocampal injury or MWM performance following hyperglycemic ischemia compared to corresponding saline-treated animals. In contrast, a lower dose of PD 81,723 (3 mg/kg) resulted in significant (P < 0.05, n = 8) reduction of hippocampal injury following hyperglycemic ischemia. Furthermore, corresponding Morris water maze performance (latency, learning index, and cumulative distance swum) was significantly improved by PD 81,723 (P < 0.05, n = 8). The results of the present study suggest that, in the presence of PD 81,723, an A(1) allosteric enhancer, endogenously produced adenosine is sufficient to exert significant neuroprotection during hyperglycemic ischemia. Moreover, the present study provides further evidence for a neuromodulatory role of adenosine during hyperglycemic ischemia.

Les facteurs qui contribuent aux effets de l'embolisation de la veine porte avant resection hepatique pour cancer hepatocellulaire ne sont pas clairs. Soixante-six patients ayant un cancer hepatocellulaire sont entres dans l'etude. On a enregistre les modifications de la fonction hepatique, de la pression dans la veine porte et le volume hepatique apres embolisation. Par analyse de regression lineaire multiple on a identifie les facteurs independants des effets de l'embolisation porte. Le rapport entre le volume du foie restant acceptable compare au volume du foie non embolise a ete calcule a partir des tests de fonction hepatique. La mortalite apres embolisation porte ou apres resection hepatique a ete nulle. On n'a note aucun changement significatif dans le taux de bilirubine totale ou du temps de prothrombine apres l'embolisation porte. Chez les patients qui ont eu une embolisation arterielle avant l'embolisation de la veine porte, on a remarque une augmentation significative des transaminases. Le seul facteur predictif des effets d'atrophie apres embolisation porte a ete l'embolisation arterielle anterieure. Le rapport entre le volume du foie non-embolise et le volume du foie restant etait inferieur a l'unite chez 18 des 40 patients, et il a augmente pour depasser l'unite apres embolisation porte dans tous les cas. L'embolisation porte a induit, respectivement, l'atrophie et l'hypertrophie du foie embolise ou non-embolise de facon suffisante, meme quand la fonction hepatique etait perturbee ou quand le foie etait cirrhotique. Les effets d'atrophie ont ete plus importants surtout lorsque l'embolisation arterielle a ete realisee avant l'embolisation porte.

We report 7 rare cases of recurrent breast cancers who presented with central nervous system (CNS) metastases as the initial relapse site without any other organ metastases. The average age of the patients at surgery was 42.6 years old of age (median 45:range 32-60), and 6 of the 7 cases (86%) were premenopausal. The mean disease-free period was 25.7 months (median 22, range 2-60 months). The primary tumors were all invasive ductal carcinomas. The estrogen receptor and progesterone receptor status of the 3 tumors available for study were all negative. The metastatic CNS lesions included the cerebrum (4 cases), cerebellum, cervical spinal cord, and meninges. In 6 out of these 7 cases (86%), the CNS metastasis was the initial recurrent lesion. Multidisciplinary treatments including surgery, radiotherapy and systemic or intrathecal chemotherapy were given. Although the mean survival time from clinical manifestations of the metastases of the 4 deceased patients was 20 months (median 20.5; range 6-33), one patient treated with surgery and radiotherapy is been still alive18 years later. These cases were also notable for the fact that the only metastatic site was in the CNS only during the entire clinical course, except for 2 cases, one with ocular adnexa metastasis, and the other with cervical lymph node metastasis. Premenopausal patients with negative hormone receptor status are more likely to develop this type of recurrence, regardless of the histological type. It is necessary to pay attention to neurological symptoms and signs during follow-up of breast cancer patients.

Three patients with tumours of the pineal region underwent interstitial Ir-192 brachytherapy. Histological diagnoses were obtained in all patients, by stereotactic biopsy and included one germinoma, one mixed pineoblastoma/pineocytoma, and one astrocytoma grade III. Our approach to pineal region neoplasms is first to decide whether stereotactic biopsy or surgery should be performed. When a pineal lesion is thought to be benign on the basis of imaging, such as benign teratoma, surgery is performed to resect the entire lesion. When a definitive diagnosis is not possible, stereotactic biopsy is performed to obtain a histological diagnosis for treatment planning, using a Brown-Roberts-Wells (BRW) stereotactic apparatus with computed tomography (CT) or magnetic resonance imaging (MRI). When a lesion is malignant and localized, stereotactic implantation of catheters for interstitial brachytherapy is performed simultaneously. Radioactive Ir-192 seeds are inserted into the catheters and maintained for 5-10 days to give 36 Gy of irradiation at the tumour periphery. Sequential CT scans and MRI after treatment revealed tumour disappearance in two patients with germinoma and high grade astrocytoma and tumour reduction in the patient with mixed pineoblastoma/pineocytoma. No significant morbidity or mortality occurred in any of these patients after stereotactic biopsy and brachytherapy. The technique and the advantages of this therapeutic approach to selected pineal region tumours are described and discussed.