The transcriptional landscape of the mammalian genome

This study describes comprehensive polling of transcription start and termination sites and analysis of previously unidentified full-length complementary DNAs derived from the mouse genome. We identify the 5' and 3' boundaries of 181,047 transcripts with extensive variation in transcripts arising from alternative promoter usage, splicing, and polyadenylation. There are 16,247 new mouse protein-coding transcripts, including 5154 encoding previously unidentified proteins. Genomic mapping of the transcriptome reveals transcriptional forests, with overlapping transcription on both strands, separated by deserts in which few transcripts are observed. The data provide a comprehensive platform for the comparative analysis of mammalian transcriptional regulation in differentiation and development.

Postoperative hyperperfusion associated with steal phenomenon caused by a small arteriovenous malformation

A 41-year-old woman presented with a small occipital arteriovenous malformation (AVM) manifesting as headache. Cerebral angiography showed an AVM in the right occipital lobe fed by the right temporooccipital artery and draining into the superior sagittal sinus and right transverse sinus. Single photon emission computed tomography showed the steal phenomenon in the ipsilateral temporal cortex fed by the main feeding artery preoperatively, and hyperperfusion in the same cortex after removal of the AVM. Postoperative systolic blood pressure was maintained between 100 and 120 mmHg to avoid disastrous hemorrhagic complications. Cerebral blood flow evaluation before and after surgery is important to avoid postoperative disastrous complications even in patients with small AVM.

Clinical features and management of brain arteriovenous malformations in elderly patients

BACKGROUND

Brain arteriovenous malformations (AVMs) of the elderly have not received sufficient attention, given the increase in age of individuals in recent years. We therefore designed a retrospective study to clarify features of brain AVMs in this age group in comparison with their counterparts in the general population.

METHODS

A retrospective study was performed, based on data for AVMs treated in Nara Medical University Hospital and affiliated hospitals over the past 13 years. The series included all cases of brain AVMs, except for pure dural AVMs, diagnosed from June 1989 to June 2003. A total of 175 patients were diagnosed as having an AVM during this period, including 32 patients more than 60 years old. Clinical features and effective treatment of brain AVMs in those over and under 60 were explored and outcome at 3 to 6 months after surgery was evaluated according to a modified neurological scale.

FINDINGS

The most common mode of presentation was intracranial hemorrhage in both groups, and this was remarkable in the elderly. Epilepsy at presentation was less frequent in the elderly (P< 0.05). In the elderly group infratentorial lesions were encountered more frequently (P< 0.05). Good or excellent outcomes of surgery were accomplished in 82.6% of the non-elderly group, and in 69.6% of the elderly group. When restricted to the grades I or II of Spetzler and Martin (S & M) grading, postoperative neurological scores of both groups were significantly better than preoperative values (P < 0.01). In the grade III cases, the non-elderly demonstrated significant improvement after surgery (P <0.01), but the elderly did not.

INTERPRETATION

Elderly patients with a brain AVM had clinical features of less frequent epileptic presentation and more frequent infratentorial lesions. It was suggested that surgery was acceptable in elderly patients with pallial AVMs of grade I and II. Surgery for grade III AVMs of the elderly remains to be clarified.

Dipyridamole protects the liver against warm ischemia and reperfusion injury

BACKGROUND

Adenosine, a metabolite of adenosine triphosphate degradation during ischemia, is reported to attenuate ischemia and reperfusion injury in several tissues. Dipyridamole is a nucleoside transport inhibitor that augments endogenous adenosine. In this study, we tested whether dipyridamole would attenuate hepatic I/R injury. For this purpose, dipyridamole was applied to a 2-hour total hepatic vascular exclusion model in dogs.

STUDY DESIGN

Dipyridamole (DYP) was given by continuous intravenous infusion for 1 hour before ischemia at a dose of 0.25 mg/kg (high-DYP, n = 6), 0.1 mg/kg (medium-DYP, n = 6), or 0.05 mg/kg (low-DYP, n = 6). Nontreated animals were used as ischemic controls (CT, n = 12). Two-week survival, systemic and hepatic hemodynamics, liver function tests, energy metabolism, adenosine 3', 5'-cyclic monophosphate (cyclic AMP) levels, platelet numbers, arachidonic acid metabolites, and histopathology were analyzed.

RESULTS

Two-week animal survival was 25% in CT, 17% in high-DYP, 100% in medium-DYP, and 17% in low-DYP. Dipyridamole significantly improved postreperfusion hepatic blood flow and energy metabolism, attenuated liver enzyme release and purine catabolite production, and augmented cyclic AMP levels. The medium dose of dipyridamole lessened platelet aggregation, thromboxane B2 production, and polymorphonuclear neutrophil infiltration, and improved survival.

CONCLUSIONS

We demonstrated marked hepatoprotective effects of dipyridamole against severe ischemia and reperfusion injury in canine livers. Dipyridamole is a promising agent for liver surgery and transplantation.

[A case of arteriovenous malformation associated with moyamoya phenomenon]

A case with arteriovenous malformation (AVM) associated with moyamoya phenomenon is reported. The 44 year-old female patient was presented with headache and vomiting. Computed tomography (CT) scan showed intraventricular hemorrhage. Cerebral angiography showed right frontal AVM and severe stenosis of right internal carotid artery. The AVM was fed by typical moyamoya vessels, Heubner's artery, and external carotid artery (ECA). We tried to embolize a bleeding point, compartment attached to lateral ventricle, but we could not. So, we embolized feeders from ECA and sent the patient to radiosurgery. We discuss here treatment and etiology of such rare condition.

Static-dynamic friction transition of FRP esthetic orthodontic wires on various brackets by suspension-type friction test

A new testing apparatus for the measurement of frictional properties was designed and the frictional coefficients were obtained and compared with each other in various combinations of brackets and orthodontic wires, including esthetic fiber-reinforced plastic (FRP) wire that was especially designed and manufactured. Three kinds of wires (stainless steel, nickel-titanium, and FRP) and four brackets (single-crystal alumina, polycrystalline alumina, polycarbonate, and stainless steel) were used. The testing was done under dry and wet conditions. The friction testing equipment was designed to attach the bracket to a C-shaped bar suspended with a variable mass, and sliding along a fixed wire. The transition between static and dynamic friction was measured as a breakaway force, with the use of a universal test machine. In addition to material properties, this testing fixture eliminates geometrical factors, such as the rotational moment at the edge of the bracket slot, deflection of the orthodontic wire, and tension of the ligature wire. Nearly ideal frictional properties between materials are obtained. The frictional properties of FRP wire were similar to those of metal wires on all brackets, except the polycrystalline alumina bracket. The frictional coefficient between the polycrystalline ceramic bracket and FRP wire was larger than that of other combinations. There was little difference in frictional coefficients between dry and wet conditions.

Association between minor physical anomalies and lateral ventricular enlargement in childhood and adolescent onset schizophrenia

OBJECTIVE

The primary purpose of this study was to investigate the association between morphological abnormalities of brain and minor physical anomalies (MPAs) in childhood and adolescent onset schizophrenia.

METHOD

Twenty-seven patients who had been diagnosed with schizophrenia according to DSM-IV criteria before 18 years of age were included in the study. MPAs were evaluated with the modified version of Waldrop scale (WS) by Green et al. Morphological abnormalities of brain was evaluated with ventricular-brain ratio (VBR) by using cerebral magnetic resonance imaging (MRI) examination.

RESULTS

A significant positive correlation was observed between WS scores and VBRs.

CONCLUSION

This result indicates a relationship between MPAs and lateral ventricular enlargement, and supports neurodevelopmental etiology in childhood or adolescent onset schizophrenia.

Melanoma chondroitin sulfate proteoglycan regulates matrix metalloproteinase-dependent human melanoma invasion into type I collagen

Tumor cell adhesion and proteolysis of the extracellular matrix proteins surrounding the cells are tightly linked processes in tumor invasion. In this study, we sought to identify components of the cell surface of a vertical growth phase melanoma cell line, WM1341D, that mediate invasive cellular behavior. We determined by antisense inhibition that melanoma chondroitin sulfate proteoglycan (MCSP) and membrane-type 3 matrix metalloproteinase (MT3-MMP) expressed on WM1341D are required for invasion of type I collagen and degradation of type I gelatin. MT3-MMP co-immunoprecipitated with MCSP in WM1341D melanoma cells cultured on type I collagen or laminin. The association between MT3-MMP and MCSP was largely disrupted by removing chondroitin sulfate glycosaminoglycan (CS) from the cell surface, suggesting CS could mediate the association between the two cell surface core proteins. Recombinant MT3-MMP and MT3-MMP from whole cell lysates of WM1341D cells were specifically eluted from CS- conjugated affinity columns. The results indicate that MT3-MMP possesses the potential to promote melanoma invasion and proteolysis and that the formation of a complex between MT3-MMP and MCSP may be a crucial step in activating these processes.

Presence of third molar germs in orthodontic patients in Japan

The purpose of this investigation was to evaluate the existence of third molar germs in orthodontic patients in Japan and to examine the relationship between the existence of third molars and sagittal maxillomandibular jaw relationships. The subjects comprised 306 patients from the orthodontic clinic of Hokkaido University Dental Hospital who were younger than 15 years. The subjects were divided into 2 groups: 1 group included 144 patients who were born between 1966 and 1969 (60s group), and the other group included 162 patients who were born between 1980 and 1987 (80s group). Assessments were made from panoramic radiographs and lateral cephalograms. The following results were obtained: (1) all 4 third molar germs were present in 77% of subjects, (2) mandibular third molars were present significantly more often than maxillary third molars, and (3) the percentage of skeletal Class III subjects who had all 4 third molars was lower than that of skeletal Class II subjects. The chi(2) test was used to determine statistical significance in differences.

Isolation and characterization of a new immortal rat astrocyte with a high expression of NGF mRNA

We have established a new line of immortalized rat astrocytes through transfection of plasmid pSV3-neo encoding the large T antigen of simian virus 40 into normal astrocytes. One of these immortalized astrocytes (ACT-57) with a flat and polygonal cell shape, exhibited stable growth in a chemically defined medium (modified N-2 medium) as well as in medium containing ordinary serum. ACT-57, retained a detectable level of expression of glial fibrillary acidic protein (GFAP) and its mRNA, and exhibited a stronger expression of nerve growth factor (NGF) mRNA than that of normal rat astrocytes or C6 glioma cells. NGF mRNA was significantly up-regulated by phorbol ester (12-O-tetradecanoylphorbol 13-acetate, TPA) and gamma-amino-n-butyric acid (GABA) but not by hydrocortisone. None of stimulants (TPA, dibutyryl cyclic AMP (db-cAMP), hydrocortisone, L-glutamate, carbacol, GABA, dopamine, or isoproterenol) changed the expression level of either brain-derived neurotrophic factor (BDNF) or neurotrophin-3 (NT-3). There was a discrete difference between ACT-57 and normal astrocytes in the response to GABA and isoproterenol. These findings imply that normal cortical astrocytes possess a functional heterogeneity whereas the clonal astrocyte, ACT-57, does not, indicating that ACT-57 cells may be useful for in vitro studies of neuron-astrocyte interactions involving the induction of neurotrophic factors such as NGF.

Crystal structure and charge distribution of YbFeMnO4

The structure of synthetic YbFeMnO(4) has been refined by single-crystal X-ray diffraction. Space group R3m, a = 3.4580 (1), c = 25.647 (3) A, V = 265.59 (3) A(3), Z = 3. Yb is in octahedral coordination, whereas Fe and Mn are disordered on a single crystallographic type of trigonal bipyramid, in which the cation is off-centred from the basal plane. Assuming perfect stoichiometry, R(1) = 0.0195, but the charge distribution (CD) analysis suggests incomplete occupation of the Yb site. Refinement of the occupancy lowers R(1) to 0.0175, resulting in s.o.f.(Yb) = 0. 963 (3), with a significant improvement of the Fourier difference. The electroneutrality is likely preserved through incomplete occupancy of one of the two oxygen sites: the compound is thus non-stoichiometric, with the formula Yb(0.963)FeMnO(3.945). Another mechanism for preserving the electroneutrality is the oxidation of a small amount of Mn(2+) to Mn(3+), which is, however, less probable because of the reduction conditions in which the sample was synthesized. Both models give a satisfactorily CD result, but they cannot be definitively distinguished by X-ray data.

[Successful treatment using low-dose carbamazepine for a patient of personality change after mild diffuse brain injury]

A 19-year-old male had a traffic accident while driving his motorbike and suffered an injury to the left frontotemporal part of the head. He remained conscious, had no focal neurological signs, and brain-computed tomography was unremarkable at the prefectural hospital, department of neurosurgery. Six months later he demonstrated a personality change, which was marked by irritability, aggression, labile moods, childishness, irresponsibility, and a lack of motivation. He sometimes made trouble for those around him, and he consulted our hospital 2 years and 9 months after the accident. He was diagnosed as having posttraumatic personality disorder and was treated with clonazepam, a dosage of up to 1.5 mg/day. Although his symptoms were moderately improved, he complained of sleepiness as an adverse effect. Carbamazepine (100 mg/day) was added in expectation of further improvement. Within a few days he improved to his preaccident personality. After the administration of clonazepam was discontinued, he maintained his good mental status. Now about two years after the initiation of therapy, he works in social welfare facilities and has no relapses. Even if a head injury is mild without definite organic signs in brain, it may have a possibility of causing personality change, which may be treatable.

Brain imaging in childhood- and adolescence-onset schizophrenia associated with obsessive-compulsive symptoms

OBJECTIVE

Childhood- and adolescence-onset schizophrenic patients with obsessive-compulsive symptoms (OCS) constitute a specific subgroup of schizophrenia. We performed magnetic resonance imaging in this group seeking evidence of neurodevelopmental insults.

METHOD

Thirty-two schizophrenic patients were compared with 19 controls. Schizophrenic subjects were divided into 15 patients with OCS (SOCS+ group; onset at 15.5 +/- 1.6 years) and 17 without OCS (SOCS- group; onset at 15.3 +/- 1.3 years). Areas of the hippocampus, frontal lobe, corpus callosum and putamen were analysed morphometrically.

RESULTS

The left hippocampus was significantly smaller in the SOCS+ group than in the SOCS- and control groups.

CONCLUSION

Reduced size of the left hippocampus in the SOCS+ group supports a neurodevelopmental etiology in this subgroup.

Use of spiral computerized tomography angiography in patients with subarachnoid hemorrhage in whom subtraction angiography did not reveal cerebral aneurysms

OBJECT

Patients with subarachnoid hemorrhage (SAH) in whom angiography does not demonstrate diagnostic findings sometimes suffer recurrent disease and actually harbor undetected cerebral aneurysms. The management strategy for such cases remains controversial, but technological advances in spiral computerized tomography (CT) angiography are changing the picture. The purpose of this prospective study was to examine how spiral CT angiography can contribute to the detection of cerebral aneurysms that cannot be visualized on angiography.

METHODS

In 134 consecutive patients with SAH, a prospective search for the source of bleeding was performed using digital subtraction (DS) and spiral CT angiography. In 21 patients in whom initial DS angiography yielded no diagnostic findings, spiral CT angiography was performed within 3 days. Patients in whom CT angiography provided no diagnostic results underwent second and third DS angiography sessions after approximately 2 weeks and 6 months, respectively. Six patients with perimesencephalic SAH were included in the 21 cases. Six of the other 15 patients had small cerebral aneurysms detectable by spiral CT angiography, five involving the anterior communicating artery and one the middle cerebral artery. Two patients in whom initial angiograms did not demonstrate diagnostic findings proved to have a ruptured dissecting aneurysm of the vertebral artery; in one case this was revealed at autopsy and in the other during the second DS angiography session. A third DS angiography session revealed no diagnostic results in 13 patients.

CONCLUSIONS

Spiral CT angiography was useful in the detection of cerebral aneurysms in patients with SAH in whom angiography revealed no diagnostic findings. Anterior communicating artery aneurysms are generally well hidden in these types of SAH cases. A repeated angiography session was warranted in patients with nonperimesencephalic SAH and in whom initial angiography revealed no diagnostic findings, although a third session was thought to be superfluous.

Ser787 in the proline-rich region of human MAP4 is a critical phosphorylation site that reduces its activity to promote tubulin polymerization

p34cdc2 kinase-phosphorylation sites in the microtubule (MT)-binding region of MAP4 were determined by peptide sequence of phosphorylated MTB3, a fragment containing the carboxy-terminal half of human MAP4. In addition to two phosphopeptides containing Ser696 and Ser787 which were previously indicated to be in vivo phosphorylation sites, two novel phosphopeptides, containing Thr892 or Thr901 and Thr917 as possible phosphorylation sites, were isolated, though only in in vitro phosphorylation. The role of phosphorylation at Ser696 and Ser787, which were differently phosphorylated during the cell cycle (Ookata et al., (1997). Biochemistry, 36: 15873-15883), was investigated in MT-polymerization, using MAP4 Ser to Glu mutants, which mimic phosphorylation at each site. Mutation of Ser787 to Glu strikingly reduced the MAP4's MT-polymerization activity, while Glu-mutation at Ser696 did not. These results suggest that Ser787 could be the critical phosphorylation site causing MTs to be dynamic at mitosis.

Spinal dural arteriovenous fistula with perimesencephalic subarachnoid haemorrhage

A case is reported of a 66 year old woman presenting with perimesencephalic subarachnoid haemorrhage (SAH) which was caused by a spinal dural arteriovenous fistula at the C1 level. The fistula drained into the venous system of the posterior cranial fossa through a perimedullary vein. The bleeding was thought to result from venous hypertension induced by the fistula. This case may support the hypothesis that perimesencephalic non-aneurysmal SAH can be ascribed to venous bleeding and that venous hypertension is the key to its pathology.

Melanoma chondroitin sulphate proteoglycan regulates cell spreading through Cdc42, Ack-1 and p130cas

Melanoma chondroitin sulphate proteoglycan (MCSP) is a cell-surface antigen that has been implicated in the growth and invasion of melanoma tumours. Although this antigen is expressed early in melanoma progression, its biological function is unknown. MCSP can stimulate the integrin-alpha4 beta1-mediated adhesion and spreading of melanoma cells. Here we show that stimulated MCSP recruits tyrosine-phosphorylated p130 cas, an adaptor protein important in tumour cell motility and invasion. MCSP stimulation also results in a pronounced activation and recruitment of the Rho-family GTPase Cdc42. MCSP-induced spreading of melanoma cells is dependent upon active Cdc42, a Cdc42-associated tyrosine kinase (Ack-1) and tyrosine phosphorylation of p130cas. Furthermore, vectors inhibiting Ack-1 or Cdc42 expression and/or function abrogate MCSP-induced tyrosine phosphorylation and recruitment of p130cas. Our findings indicate that MCSP may modify tumour growth or invasion by a unique signal-transduction pathway that links Cdc42 activation to downstream tyrosine phosphorylation and subsequent cytoskeletal reorganization.

Effects of aging on oxytalan fibre in mouse periodontal ligament

The reactions of periodontal tissues to the mechanical stimulation of teeth seem to be different in patients of different ages. Although the effects of aging on other structures of the periodontal tissues, i.e., collagen fibre, bone, and cementum, have been reported, there is very little information available concerning the effects of aging on periodontal oxytalan fibre, which is reportedly the only elastic element in the human periodontal ligament. The purpose of this research was to clarify the aging related changes in the distribution of oxytalan fibres in the periodontal ligament of mice. Histological sections of the periodontal ligament of the lower first molar of 10-week-old (control group) and 1-year-old (aged group) ICR mice were specifically stained for oxytalan fibres with aldehyde fuchsin after preoxidization, and observed by light microscopy and confocal laser scanning microscopy (CLSM). In the aged group, oxytalan fibres seemed to be more prevalent around blood vessels in comparison with the control group. Furthermore, CLSM clearly showed that oxytalan fibres in the aged group were relatively more tortuous and complex than those in the control group. This tortuosity and complexity might imply that the oxytalan fibres in aged mice have lost a considerable amount of their original elasticity. While further study of these changes is required, these results may help orthodontists to establish better treatment strategies and methods for adult orthodontic patients.

Subarachnoid hemorrhage from intracranial dissecting aneurysms of the anterior circulation. Two case reports

Two rare cases of intracranial dissecting aneurysms of the anterior circulation associated with subarachnoid hemorrhage (SAH) are described. A 56-year-old female presented with a dissecting aneurysm in the proximal segment of the left middle cerebral artery. Proximal occlusion of the affected artery and a superficial temporal artery-middle cerebral artery anastomosis were performed, but the outcome was poor. A 61-year-old male presented with a dissecting aneurysm in the proximal segment of the left anterior cerebral artery. Clipping was enhanced by a piece of fascia lata, allowing patency of the affected artery with a satisfactory outcome. Dissecting aneurysm of the carotid system should be considered in a patient with SAH but no evidence of berry aneurysm.

Intracranial Castleman's disease of solitary form. Case report

This 62-year-old woman presented with clumsiness in her right hand. Magnetic resonance imaging demonstrated a small lesion mimicking a meningioma, which had arisen from the tentorium and contained notable edema. Full recovery was achieved by total removal of the lesion, which was diagnosed as a lymphoid mass resembling giant lymph node hyperplasia on histological examination. The lack of notable findings on whole-body and laboratory studies was compatible with a rare case of intracranial Castleman's disease of solitary form. The authors document clinical, neuroradiological, and pathological features of this rare disease.