Trinuclear Cu(II) complex for internucleoside linkage-specific cleavage of RNA

Trinuclear Cu(II) complex of N,N,N',N',N",N"-hexa[(2-pyridyl)methyl]-1,3,5-tris(aminomethyl)benzene (L3A) exhibits remarkable substrate-specificity for hydrolysis of 2'-->5' and 3'-->5' ribonucleotides. Up(2'-->5')U is hydrolyzed much efficiently than is Up(3'-->5')U, but Ap(3'-->5')A is overwhelmingly preferable to Ap(2'-->5')A.

Site-selective artificial ribonuclease using pinpoint RNA activation

An acridine residue attached to the end or the inside of a DNA activates the target phosphodiester linkages in complementary RNA. Due to this pinpoint activation, the RNA is site-selectively and efficiently cleaved at these linkages by various free metal ions under mild condition. Spectroscopic analyses show that the acridine moiety is sandwiched between neighboring bases, and pushes the opposite nucleotide out of the hetero-duplex.

Photo-regulation of RNA polymerase reaction by use of modified DNA carrying an azobenzene

Transcription reaction by T7-RNA polymerase was photo-regulated on the basis of two strategies as depicted in Scheme 1. It was found that incorporation reaction of azobenzene-tethered uridine triphosphate proceeded only when azobenzene took trans-form (Scheme 1(A)). On the other hand, the transcription was more efficient when the azobenzene moiety, tethered to the non-template strand of the promoter DNA, was in its cis-form under UV irradiation (Scheme 1(B)). Thus, azobenzene-tethered DNAs are promising for the photo-regulation of gene-expression.

Transfemoral, transvenous embolisation of dural arteriovenous fistula involving the isolated transverse-sigmoid sinus from the contralateral side

BACKGROUND

A dural arteriovenous fistula (AVF) involving the transverse-sigmoid (T-S) sinus which is occluded at its proximal and distal ends i.e., an isolated sinus, runs the risk of haemorrhaging or causing serious neurological deficits as a result of its retrograde leptomeningeal venous drainage. While lesions of this type have not been considered to be treatable by percutaneous, transvenous embolisation, this paper challenges this view.

CASE PRESENTATION

Two middle-aged men with dural AVFs involving the isolated left T-S sinus presented with motor aphasia due to focal brain edema or haemorrhage. Under local anaesthesia, transfemoral, transvenous embolisation was performed with a microcatheter that was passed through the occluded proximal transverse sinus from the right (contralateral) side. The isolated sinus was then occluded with platinum coils. This embolisation resulted in angiographic and clinical cure of dural AVFs in both patients.

INTERPRETATION

Transfemoral, transvenous embolisation is a therapeutic alternative for the treatment of dural AVFs involving the isolated T-S sinus. Embolisation obviates the need for craniotomy and general anaesthesia, which are required for the established modes of treatment, i.e., direct surgery or direct percutaneous sinus packing.

Anterior choroidal artery variant and acute embolic stroke. Case report

The anterior choroidal artery has the cortical branches to the temporal, parietal, and occipital lobes in the early embryological stage, which later become the posterior cerebral artery distal to the posterior communicating artery (P2-4). Acute embolic stroke occurred in a 57-year-old man with an anterior choroidal artery having such a persistent embryonic branch to the temporal lobe. Recognition of this embryological form of the anterior choroidal artery is clinically important in acute cerebral ischaemia because the cerebral region between the territories supplied by the middle cerebral artery and the anterior choroidal artery is shown on carotid angiography as an avascular area, which could be misunderstood as a region of the acute ischaemia.

Simultaneous dissection of intra- and extracranial vertebral artery. Report of two cases and review of literature

Two patients who developed subarachnoid haemorrhage are presented. The first patient was a 41-year-old woman whose angiograms showed right extracranial vertebral artery (VA) dissection starting at the C2 level extending to the intracranial VA near the VA union. Proximal occlusion of the right VA by the endovascular approach was performed. The second patient was a 57-year-old man whose angiograms showed the left intracranial VA dissection distal to the posterior inferior cerebellar artery and an extracranial aneurysmal dilatation of the left VA at the C1 level and extracranial VA dissection in the V3 portion of the right VA. Left intracranial VA dissection was surgically trapped, and the remaining lesions were conservatively treated. Simultaneous dissection of the intracranial and extracranial portions of the VA is rare. Such lesions usually cause brain ischaemia, but may cause intracranial subarachnoid haemorrhage.

Vein of galen aneurysms. Experience with eleven cases

SUMMARY

Eleven patients with so-called "vein of Galen aneurysms" are reported, six of whom presented with vein of Galen aneurysmal malformations (four with choroidal type and two with mural type malformations). The remaining five patients presented with vein of Galen aneurysmal dilatations secondarily due to an arteriovenous malformation in one patient, an arteriovenous fistula in another, dural arteriovenous fistulas in two patients, and a varix in another. Treatments for these patients were individualised with consideration given to the clinical manifestations and the angioarchitecture of their lesions. Endovascular intervention played a critical role in the treatment of these vein of Galen aneurysms.

Neonatal exposure to genistein reduces expression of estrogen receptor alpha and androgen receptor in testes of adult mice

We investigated the long-term estrogenic influence of genistein on the male reproductive system in mice. Newborn ICR male mice were treated with genistein (10, 100, or 1,000 microg/mouse) for neonatal 5 days. As positive control, administration of diethylstilbestrol (0.5-50 microg/mouse) was carried out. In mice exposed to genistein,we examined weight of testes, sperm counts, sperm motility, and mRNA expression levels of estrogen receptor a (ERalpha) and androgen receptor (AR) at 4, 8 or 12 weeks after birth. Moreover, at 12 weeks of age, we evaluated protein level of ERalpha. In our conventional reproductive-toxicological study (weight of testes, sperm counts and sperm motility), neonatal transient exposure to genistein did not show adverse effects on the male reproductive system in 4, 8 or 12 week old mice. However, in mice treated with genistein mRNA expression levels of ERa and AR were reduced at 8 weeks. This reduction was recovered at 12 weeks in mice treated with a lower dose (10 microg) of genistein but not in those with higher doses (100 microg and 1,000 microg). In addition, ERa protein levels tended to decrease in 12 weeks of adulthood. Our results exhibited that the disruption of gene expression continued for long term such as 3 months after administration of genistein, even if no effect was found at conventional reproductive-toxicological level. We have shown that neonatal administration of weak estrogenic compound (genistein) affects male reproductive organs at molecular levels in adulthood.

Evolution of incidentally-discovered fusiform aneurysms of the vertebrobasilar arterial system: neuroimaging features suggesting progressive aneurysm growth

This study investigated the natural history and biological behavior of incidental fusiform aneurysms in four patients with incidental fusiform aneurysms of the vertebrobasilar arterial system who had been followed up for more than 3 years (mean 3.5 years). Two lesions remained the same size, and two lesions gradually grew. Angiography showed the non-growing fusiform aneurysms as a circumferentially or unilaterally fusiform dilatation of a short segment of the vertebral artery with smooth walls and a steep slope of the dilatation, and the growing fusiform aneurysms as unilaterally fusiform involving a long segment of the vertebral artery or basilar artery with irregular walls and a gentle slope of dilatation. Magnetic resonance (MR) imaging demonstrated the non-growing fusiform aneurysms as a signal-void area, and the growing fusiform aneurysms as high and intermediate signals in addition to the normal flow void. The heterogeneous MR intensities probably correspond to turbulent flow, laminar flow, thrombosis, or intramural hematoma. Differentiation of growing and non-growing fusiform aneurysms is very difficult at the initial diagnosis. However, enlargement of the fusiform aneurysms is consistent with hemorrhage into the aneurysmal wall, which is confirmed by MR imaging. Fusiform aneurysms with the characteristics of the growing aneurysms cannot be overlooked because of the potential to develop into giant fusiform aneurysms which are very difficult to manage therapeutically.

Distal stump of an occluded intracranial vertebral artery at the vertebrobasilar junction mimicking a basilar artery aneurysm

The distal stump of an occluded intracranial vertebral artery (VA) can mimic a basilar artery aneurysm of the vertebrobasilar junction. Their differentiation is crucial to establishing the appropriate treatment. We report two cases with occlusion of the distal stump of the VA due to atherosclerosis and arterial dissection. Magnetic resonance images with three-dimensional constructive interference in steady state sequences are useful in revealing the occluded segment as a continuous anatomical structure from the proximal VA to the basilar artery. This information may prevent unnecessary exploratory surgery for a suspected basilar artery aneurysm.

A 3.2-French cerebral diagnostic catheter for all ages: technical note

We report our experience with a 3.2F cerebral diagnostic catheter system. Thirty patients (aged 6 months to 76 years) had undergone cerebral angiography. All targeted brachiocephalic vessels were catheterized except for one artery (98.9% success rate). The image quality obtained with the 3.2F catheter was judged to be comparable with that using the 4F catheter in all cases. This catheter system could be used for cerebral angiography as the standard for patients of all ages.

Primitive trigeminal artery variant aneurysm treated with Guglielmi detachable coils--case report

A 69-year-old woman had suffered from diplopia on right lateral gaze for the last 4 months due to right abducens nerve paresis. Right carotid angiography showed a cavernous internal carotid artery (ICA) aneurysm of 17 x 16 x 14 mm size and a primitive trigeminal artery (PTA) variant supplying the territory of the posterior inferior cerebellar artery. Intraluminal occlusion of the aneurysm was performed with 15 Guglielmi detachable coils. The flow of the PTA variant and the ICA was preserved. Right abducens nerve paresis improved partially. PTA variant is a primitive artery originating from the cavernous ICA supplying the cerebellum without opacification of the basilar artery. Only four of the 67 cases of PTA variant were associated with an aneurysm of the PTA variant. The possibility of this rare association should be considered when treating cavernous portion aneurysm because of the risk of cerebellar ischemia.

Rapid normalization of marked dilatation of the cerebral duro-venous system in a newborn infant mimicking a great vein of Galen varix

A newborn infant with a marked dilatation of the cerebral duro-venous system is presented. The patient was diagnosed as having a vein of Galen aneurysmal varix by a cranial ultrasound examination immediately following delivery. Computed tomographic angiography on the following day, however, showed a marked dilatation of the cerebral duro-venous system, including the great vein of Galen, superior sagittal sinus, torcular herophili and transverse sinuses. There were no arteriovenous fistulas at the vein of Galen. Dilatation of the duro-venous system and concomitant heart failure subsided rapidly after intravenous administration of indomethacin for the treatment of the patent ductus arteriosus on the fourth day of life. Dilatation of the duro-venous system in a newborn infant should be differentiated from any form of vein of Galen aneurysm.

The second EF-hand is responsible for the isoform-specific sorting of myosin essential light chain

It has been known that isoforms of myosin essential light chain (LC) exhibit the isoform-specific sorting within cardiac myocytes and fibroblasts. In order to analyze which domain of LC is responsible for the sorting, various chimeric cDNA constructs between human nonmuscle isoform (LC3nm) and chicken fast skeletal muscle isoform (LC3f) were generated and expressed in cultured chicken cardiac myocytes. If chimeras contained LC3f sequence at the place that was restricted by BssHII and PstI, they were preferentially sorted to sarcomeres and precisely localized at A-bands, and their incorporation levels into the A-bands were identical with that of the wild type LC3f. However, other chimeras were distributed throughout the cytoplasm like the wild type LC3nm. Comparison of amino acid sequences revealed that 12 amino acids are different between chicken LC3f and human LC3nm in the BssHII-PstI fragment, and these amino acids are located within the second EF-hand of LC. These results indicated that the second EF-hand is responsible for the isoform-specific sorting of LC. Although the second EF-hand is not included in the key contacts with myosin heavy chain, it is supposed that this domain is important for the relative disposition of neighboring domains. Thus, the 12 amino acids in the second EF-hand might play a key role for modulation of overall configuration of LC, thereby influencing the precise association of the key contacts.

[Treatment for brain metastasis from lung cancer in the era of radiosurgery]

OBJECTIVE

The treatment for brain metastasis has undergone remarkable changes since the development of radiosurgery. We investigated the results of treatment for brain metastasis from lung cancer since the initiation of gamma knife radiosurgery (GKRS) and we discuss the usefulness of GKRS combined with other treatments in cases with recurrence.

METHODS

We treated 142 patients with brain metastasis from lung cancer. Sixteen patients were treated surgically, 11 patients were treated with whole brain radiation therapy (WBRT), and 115 patients were treated with GKRS. Our treatment plan is to use GKRS in cases with less than 5 lesions and lesions less than 3 cm in mean diameter. We use WBRT in cases with 5 or more lesions, and surgery in cases with lesions 3 cm or larger. If new lesions or tumor regrowth appeared after the initial treatment, we retreated them with one of the methods mentioned above.

RESULTS

Twice or three-time treatments were performed in 30 patients. Median survival including all cases was 10 months and the number of deaths due to local treatment failure was only 5 (6.5%) out of the total 77 deaths which occurred.

CONCLUSION

We were able to carry out less invasive treatment for brain metastasis from lung cancer by utilizing GKRS. Though we have to consider the indications for other treatments, we can say that radiosurgery is usually the treatment of first choice for brain metastasis from lung cancer. When new lesions appear in cases where a particular initial treatment was used, it is possible to maintain or improve the quality of life by retreatment, using a combination of GKRS, surgery or WBRT, to prolong the patient's life.

Interventional neuroangiography in neonates

Two neonates with either vein of Calen aneurysmal malformation or dural sinus malformation (congenital dural arteriovenous fistula at the torcular herophili) are reported. In neonatal interventional neuroangiography, special attention should be paid to body temperature, contrast material, infusion fluid, heparin, and angio-equipment. In the neonatal period, the umbilical approach provides unique access routes to both arterial and venous sides of the cerebral circulation. Among them, transumbilical venous, transcardiac approach through the foramen ovale allows transarterial intervention from the venous side.

"Early" apoplexy due to traumatic intracranial aneurysm--case report

A 76-year-old man presented with a traumatic aneurysm of the left internal carotid artery which caused repeated subarachnoid hemorrhages within 20 hours of a fall from a height. Early computed tomography (CT) detected no brain abnormalities, but repeat CT found subarachnoid hemorrhage. Internal carotid angiography detected a pseudoaneurysm, which was not treated because of his poor clinical condition. He died of multiple organ failure. Early detection of a traumatic intracranial aneurysm is important for the prevention of aneurysmal rupture, or "delayed" apoplexy. Review of 171 cases with traumatic aneurysms from the literature found that false negative angiography occurred only in three cases on post-trauma day 7 and thereafter. Early diagnostic angiography within a week of the initial trauma is indicated if traumatic aneurysm is suspected to detect early signs of irregularity, spasm, and narrowing of the arterial wall. Repeat angiography is indicated if aneurysmal formation is still highly suspected in spite of negative initial angiography.