Preparation of Stable Silver Nanoparticles Having Wide Red-To-Near-Infrared Extinction.

The synthesis of silver nanoparticles (AgNPs) within the interlayer space of transparent layered titania nanosheet (TNS) films is investigated. A considerable number of silver ions (≈70% against the cation exchange capacity of the TNS) are intercalated in the TNS films using methyl-viologen-containing TNSs as a precursor. The silver ion (Ag+)-containing TNS films are treated with aqueous sodium tetrahydroborate (NaBH4), resulting in a gradual color change to bright blue. Various structural analyses clearly show that crystalline AgNPs are generated within the interlayer space of the TNSs. The NaBH4-treated films show intense and characteristic near-infrared (NIR) extinction spectra up to 1800 nm. The stability of the AgNPs within the TNS against oxygen and moisture is also investigated, and 96% and 82% of the AgNPs remain after standing in air for 1 month and 1 year, respectively. The NIR extinctions of the AgNP-containing TNS films are further extended by employing different preparation procedures, for example, using sintered TNS films as starting materials and irradiating the Ag+-containing TNSs with ultraviolet (UV) light. The obtained AgNP-containing TNS films exhibit photochemical activities in the production of hydrogen from ammonia borane under visible-light irradiation and the decomposition of nitrogen monoxide under UV-light irradiation.

[A case of traumatic petrous portion internal carotid artery aneurysm treated by endovascular parent artery occlusion].

Traumatic aneurysms are rare lesions. They differ markedly from saccular aneurysms in their clinical presentation and therapy. Early diagnosis of traumatic aneurysms is usually difficult. A 52-year-old female presented with massive epistaxis and ear bleeding caused by a traffic accident. On admission, her consciousness level was 7 points of the Glasgow coma scale. Computed tomography revealed hematoma in the sphenoid sinus and fractures in the right petrous bone, and right acute subdural hematoma. 7 years after trauma, she presented ear bleeding. Cerebral angiography showed a giant traumatic aneurysm at the petrous segment of the right internal carotid artery. Test occlusion of the right internal carotid artery was performed and was well tolerated without development of focal neurological deficits, so the right internal carotid artery was occluded using endovascular techniques. We recommend that more attention be paid to the traumatic aneurysm of the C4 to C5 portion when patients with skull base fracture are diagnosed.

Role of brain perfusion single-photon emission tomography in traumatic head injury.

This investigation examined the role of brain perfusion single-photon emission tomography (SPET) in traumatic head injury in 35 patients. The results were compared with those of X-ray computerized tomography (CT) and magnetic resonance imaging (MRI). CT and MRI detected brain contusions in seven patients, subarachnoid haemorrhage in one patient and both in nine patients. In 16 of the 17 subjects (94%), SPET with technetium-99m-hexamethylpropyleneamine oxime (Tc-HMPAO) revealed CT/MRI-negative abnormalities, such as hypoperfusion in the contre-coup region, frontal hypoperfusion related to personality change and cerebellar hypoperfusion associated with vertigo. In two patients presenting with diffuse axonal injury in the brainstem, hypoperfusion in the frontal cortex on the affected side was observed on SPET. SPET demonstrated hypoperfusion in the adjacent cortex, with no abnormality on either CT or MRI, in six of seven patients exhibiting acute epidural haematoma. SPET failed to provide additional information in two of five patients with acute subdural haematoma and in one of two patients displaying chronic subdural haematoma. In four of nine patients with post-traumatic amnesia, SPET detected hypoperfusion in the temporal lobe, with no abnormality on either CT or MRI. In five of eight patients with vertigo, SPET detected hypoperfusion in the morphologically normal cerebellum. In seven cases involving personality change, frontal hypoperfusion was observed in four; moreover, a markedly non-homogeneous pattern was evident in the remaining three. Overall, SPET afforded additional information in 26 patients (74%). CT possesses an advantage with respect to the detection of haemorrhagic lesions. MRI provides more precise information regarding contusions and axonal injury. Frequently, SPET may be the only examination to reveal perfusion abnormalities which are related to symptoms in the absence of other objective findings, such as post-traumatic amnesia, vertigo or personality change.

Calcification on the ventricle wall associated with a shunt tube--case report.

A 53-year-old man with renal failure presented with symptoms of shunt malfunction 11 years after placement of a ventriculoperitoneal shunt. Computed tomography showed high-density lesions on the lateral ventricle wall around the shunt tube. The shunt tube was replaced under monitoring with a neuroendoscope. The resected specimen from the ventricle wall lesion showed calcification and fibrosis. Disturbed calcium and phosphate metabolisms associated with renal failure may have been involved in this abnormal calcification on the ventricle wall.

Differential diagnosis in patients with ring-like thallium-201 uptake in brain SPECT.

UNLABELLED: This study was performed to investigate lesions with ring-like thallium-201 (201Tl) uptake and to determine whether SPECT provides any information in differential diagnosis. METHODS: A total of 244 201Tl SPECT images were reviewed. In each study, early (15 min postinjection) and late (3 hr) brain SPECT images were obtained with 111 MBq of 201Tl. The early uptake ratio (ER; lesion to normal brain average count ratio) and the late uptake ratio (LR) and the L/E ratio (ratio of LR to ER) were calculated. RESULTS: Ring-like uptake was observed in pre-therapeutic 26 SPECT images, including ten glioblastoma multiformes (ER, 3.45 +/- 0.64; LR, 2.74 +/- 0.54; L/E ratio 0.80 +/- 0.13), five meningiomas (6.48 +/- 2.34; 4.41 +/- 1.41; 0.72 +/- 0.19), four metastatic lung cancers (3.47 +/- 1.23; 2.40 +/- 0.98; 0.70 +/- 0.14), four brain abscesses (2.48 +/- 1.06; 1.59 +/- 0.30; 0.78 +/- 0.15), one invasive lesion of squamous cell carcinoma from the ethmoid sinus (1.54; 1.52; 0.99), one medulloblastoma (3.53; 3.52; 1.00) and one hematoma (3.32; 2.36; 0.71). The ER of meningioma was significantly higher than those of glioblastoma multiforme (p < 0.0005), metastatic lung cancer (p < 0.005) and brain abscess (p < 0.0005). There were no significant differences among these three entities. The LR of meningioma was significantly higher than those of glioblastoma multiforme (p < 0.005), metastatic lung cancer (p < 0.005) and brain abscess (p < 0.0001). The LR of brain abscess was significantly lower than that of glioblastoma multiforme (p < 0.05). The L/E ratio could not differentiate these four entities. CONCLUSION: High ER and high LR in a lesion with ring-like uptake is likely an indicator of meningioma. The LR of brain abscess was significantly lower than that of glioblastoma multiforme, but 201T1 SPECT has still difficulty in differentiating abscess from brain tumor.