Vertebrobasilar junction fenestration associated with dissecting aneurysm of intracranial vertebral artery

BACKGROUND

Vertebrobasilar junction fenestration is considered to be a subtype of fenestration of the proximal basilar artery, which has been described only in autopsy cases. The fenestration associated with a dissecting vertebral aneurysm is extremely rare.

CASE DESCRIPTION

A 47-year-old man presented with subarachnoid hemorrhage. The four-vessel angiogram showed a fusiform dilatation with an intimal flap of the left vertebral artery distal to the origin of the posterior inferior cerebellar artery and a fenestration at the vertebrobasilar junction, in which a small limb of the fenestration arising from the distal portion of the left vertebral artery bridged the proximal basilar trunk, while another limb had a large diameter showing the same diameter as the basilar artery. The dissecting aneurysm was treated with body clipping by directly clipping the ruptured portion of the aneurysm via a suboccipital approach in an early operation 48 hours after the ictus. The patient had a good recovery and returned to his work. He is well at a 5-year follow-up.

CONCLUSIONS

The relevant angiographic features of the vertebrobasilar junction fenestration and the surgical treatment of such associated aneurysms are discussed.

Proliferative cell nuclear antigen expression in follicular tumours of the thyroid with special reference to oxyphilic cell lesions

The expression of proliferative cell nuclear antigen (PCNA) in follicular tumours of the thyroid was examined by immunohistochemistry. Both usual nonoxyphilic cell follicular tumours (non-OCT) and oxyphilic cell tumours (OCT) were subdivided into benign, indeterminate, encapsulated carcinoma, and widely invasive carcinoma types. Among non-OCT the percentages of PCNA-positive cells in benign tumours, encapsulated carcinomas, and widely invasive carcinomas was 2.5%-8.6%, 11.8%-39.1%, and 18.6%-20.0%, respectively. There was a statistically significant difference between benign tumours and encapsulated or widely invasive carcinomas, as in previous studies. A value of 10% was appropriate to distinguish benign from malignant lesions. PCNA-positive cells in indeterminate-type non-OCT were not significantly different from those in benign tumours, ranging from 4.3%-19.6%, and occurring at more than 10% in three of six tumours. Among OCT the positivity was less than 10% in benign tumours (4.5%-7.8%) and more than 10% in malignant tumours (14.1%-35.9%) and all the eight indeterminate tumours (12.5%-27.3%), with a statistically significant differences between the benign tumour and each of the latter types. These results indicate that the examination of PCNA is valuable in diagnosis of thyroid follicular tumours and that the use of similar diagnostic criteria may be warranted in both non-OCT and OCT.

Possible role of metallothionein in the cellular defense mechanism against UVB irradiation in neonatal human skin fibroblasts

The role of metallothionein (MT) in protecting skin cells against UVB irradiation was investigated. Fibroblast strains from normal adult (HS-K) and neonatal (NB1RGB) human skins as well as keratinocyte strains from human skin (SV40-HSK) and newborn Balb/c mouse skin (Pam 212) were exposed to UVB irradiation. The sensitivity of HS-K and NB1RGB cells to UVB irradiation was similar; those of SV40-HSK and Pam 212 cells were two- and six-fold as sensitive to UVB irradiation as HS-K cells, respectively. The HS-K cells contained the greatest cellular reduced form of glutathione (GSH) levels compared to the three other skin cells: the levels were 13-, 7- and 6-fold of those in NB1RGB, SV40-HSK and Pam 212 cells, respectively. These results indicated that the sensitivity of skin cells to UVB irradiation was not always associated with their endogenous GSH levels. In particular, despite the fact that NB1RGB cells contained a relatively small amount of GSH, they were less sensitive to UVB irradiation. NB1RGB cells contained 4-30 times more MT than those in other skin cells examined. The sulfhydryl residues of MT molecules in the NB1RGB cells were estimated to be mostly unoccupied by metals, suggesting they act in a similar way to those of GSH. Moreover, NB1RGB cells in which the MT content was elevated by dexamethasone (1 microM) or Zn2+ (7 micrograms/mL) treatment were more resistant to UVB irradiation than nontreated ones. These results suggest that, at least in neonatal human skin fibroblasts, MT may play a role in protection against UVB irradiation.

Electroencephalographic activity associated with shifts of visuospatial attention

The neural processes underlying shifts of visuospatial attention were studied in normal adults by non-invasive recording of brain electrical activity. Event-related evoked potentials (ERPs) were recorded during target detection tasks with targets preceded by central or peripheral directional cues in the visual field, which are hypothesized to provoke voluntary and reflexive shifts of spatial attention. Reaction time to targets varied as a function of cue type and cue-target interval, indicating that the tasks induced shifts of spatial attention across the visual field. Event-related evoked potential recordings showed that central cues elicited negative potential shifts starting 240 ms after cue onset over posterior scalp sites contralateral to the cued visual field, which spread to anterior scalp sites over time. After 500 ms post cue, negative potentials were more negative in right temporal parietal sites regardless of cue direction. Peripheral cues enhanced the N1 component (140-200 ms post cue) over the contralateral hemisphere. Following N1 enhancement, a sustained negative potential shift appeared after 460 ms post cue at posterior scalp sites contralateral to cued field and spread over the temporal and central regions. These results suggest that the neural processes underlying spatial selection are initiated in the posterior region and that other cortical activities are recruited in a serial fashion. Symmetrical early activation of each contralateral hemisphere suggest independent involvement of the hemispheres in the early stages of shifting attention toward the contralateral visual field. A predominant contribution of the right hemisphere to sustained spatial attention was demonstrated in the late stage of cue processing at the right temporal and parietal regions. Different ERP patterns generated by central and peripheral cues support the hypothesis that distinct neural systems are involved in voluntary and reflexive mechanisms of attention shift.

A case of cytomegalovirus mononucleosis associated with pleural effusion

A 5 year old boy had a spiky fever accompanied by a mild pharyngitis, cervical lymphadenopathy and hepatosplenomegaly. Laboratory findings revealed leukocytosis with 26% atypical lymphocytes, and liver dysfunction. A chest X-ray showed pneumonia and a considerable amount of pleural effusion. Serum antibody titers for cytomegalovirus (CMV) were elevated significantly and CMV-DNA (polymerase chain reaction) was detected in the pleural effusion. Only 13 cases of pleural effusion associated with infectious mononucleosis have been reported previously in the literature, but there was no documentation that proved CMV infection. The case reported here suggests that the pleural effusion was caused by the infiltration of mononuclear cells to the pleura as a result of systemic inflammation, and the possible alternative of host immune response against CMV was related to recent Varicella zoster virus infection.

Subarachnoid hemorrhage due to rupture of infundibular dilation of a circumflex branch of the posterior cerebral artery: case report

The authors describe a rare case in which an infundibular dilation at the origin of a circumflex branch of the P1 segment of the posterior cerebral artery caused subarachnoid hemorrhage. Wrapping was performed by a subtemporal approach in the delayed stage. At the time of surgery, the rupture point was found in the infundibular dilation.

Deregulated expression of c-fos disturbs proliferative responses of B cells to sIg cross-linking

B cell activation by surface immunoglobulin (sIg) cross-linking is accompanied by transient expression of the c-fos protooncogene. This expression is strictly controlled in the B cells. To investigate a biological implication of the c-fos expression in the process of B cell activation by sIg cross-linking, we examined the proliferation of splenic B cells from H2-c-fos transgenic mice. Constitutive expression of the c-fos gene perturbs de novo synthesis of RNA and DNA in the B cells stimulated with anti-IgM antibody. Early events of signal transduction such as an increase in intracellular free calcium level and an induction of the endogenous immediate early genes (c-fos and c-myc) were apparently intact in those B cells. When the sIg stimulation of B cells was mimicked by the costimulation with 12-O-tetradecanoylphorbol 13-acetate and ionomycin, H2-c-fos B cells required higher concentrations of ionomycin for the optimal proliferative responses, suggesting that calcium-dependent signal transduction pathways are disturbed in those B cells. These results demonstrate a novel regulatory effect of c-fos protein on the proliferation of B cells mediated by sIg cross-linking.

[Significance of periventricular hyper-intensity in T2 weighted MRI on memory dysfunction and depression after stroke]

We studied the effect of periventricular hyperintensity (PVH) in T2 weighted MRI on memory function and post-stroke depression in 159 patients with cerebrovascular diseases. Memory function was assessed with Hasegawa's scale, and depressive state was estimated with Zung's self-rating depression scale. Patients showing diffusely distributed PVH had significantly low scores in memory function tests. Localized PVH around the anterior horns of the laterals ventricle was also associated with impaired memory function when the area of PVH was large. The incidence of post-stroke depression was high in patients with large PVH around the anterior horn in comparison with patients with PVH around the posterior horn. The severity of PVH around the posterior horn did not affect memory function and post-stroke depression. These findings suggest that memory dysfunction and post-stroke depression were accelerated by the diffusely or anteriorly distributed PVH.

Respiratory load compensation during hypercapnic ventilatory response in pulmonary emphysema

The purpose of this study is to examine the relationship between mechanical factors and the load compensation during hypercapnia in emphysema. In 36 clinically stable patients, we conducted pulmonary function tests and hypercapnic ventilatory response (HCVR) tests with and without inspiratory flow-resistive loading (IRL) (17 cm H2O/L/s). The mean value of HCVR significantly decreased with IRL, while that of the mouth occlusion pressure (P0.1) response increased. Regardless of IRL, the HCVR values were correlated with FEV1/FVC and airway resistance. The load compensation, evaluated by the ratio of the HCVR value and the P0.1 response before and after IRL, was inversely correlated with percent FRC (r = -0.38, r = -0.39; both p < 0.05). Breathing pattern analysis at the end-tidal pressure of carbon dioxide of 55 mm Hg elicited the decrease of (tidal volume/inspiratory time (VT/TI) and the increase of TI and TI/TTOT. Although the absolute changes of VT and f were inconsistent among subjects, each relative ratio before and after IRL was correlated again with percent FRC (r = -0.46, r = 0.44: both p < 0.01). Therefore, the position of the inspiratory muscles at the onset of inspiration may influence the load compensation during hypercapnia in emphysema.

A clinical and histopathological study of factors affecting MRI signal intensities of pituitary adenomas

Our aim was to elucidate the factors which determine the MRI signal intensities of pituitary adenomas. We examined 51 patients with surgically-confirmed pituitary adenomas. Using a spin-echo pulse sequence (SE 500/15), coronal and sagittal images (3 mm slices) were obtained. Signal intensities on T1-weighted images were measured in the parenchyma of the adenoma and in normal grey matter. The relative intensity of the adenoma was assessed by calculating the ratio of its signal intensity to that of the normal grey matter of the same patient. Paraffin-embedded sections were used for haematoxylin and eosin staining. The number of cells in a prescribed area was counted, and the mean of five such counts was taken as the cell density. Immunohistochemically stained sections using antibodies for various pituitary hormones were similarly examined; the ratio of the total number of hormone-positive cells to the overall total number of adenoma cells was calculated. Four independent variables were used in the analysis: the age of the patient, the maximum diameter of the adenoma, the cell density and the proportion of hormone-positive cells in the adenoma and, with the signal intensity ratio as the dependent variable, a multiple regression analysis was performed. This revealed that the the greatest influence upon the signal intensities on T1-weighted images was the proportion of hormone positive cells.

Purification and characterization of a Bacillus sp. SAM1606 thermostable alpha-glucosidase with transglucosylation activity

We purified a novel alpha-glucosidase to homogeneity from an Escherichia coli recombinant transformed with the alpha-glucosidase gene from thermophilic Bacillus sp. SAM1606. The enzyme existed as mono- and multimeric forms of a promoter protein with a relative molecular weight of 64,000 and isoelectric point of 4.6. We isolated a monomeric form of the enzyme and characterized it. The enzyme was unique among the known alpha-glucosidases in both broad substrate specificity and high thermostability. The enzyme hydrolysed a variety of O-alpha-D-glucopyranosides such as nigerose, maltose, isomaltose, sucrose, and trehalose efficiently. The molecular activity (k0) and the Michaelis constant (Km) values at 55 degrees C and pH 6.0 for sucrose were 54.6 s-1 and 5.3 mM, respectively. The optimum pH and temperature for hydrolysis were pH 5.5 and 75 degrees C, respectively. The enzyme exhibited a high transglucosylation activity: it reacted with 1.8 M sucrose at 60 degrees C for 70 h to yield oligosaccharides containing theanderose in a maximum yield of 35% (w/w). High thermostability of the enzyme (stable up to 65 degrees C at pH 7.2 for 10 min) permits the transglucosylation reaction at high temperatures, which would be beneficial for continuous production of oligosaccharides from sucrose.

Protein kinase C and protein kinase A regulate the expression of angiotensin II receptor mRNA in smooth muscle cells

Using reverse transcription polymerase chain reaction and fura-2 microfluorometry of intracellular Ca2+ concentrations, we investigated the effects of angiotensin II and cyclic AMP on the expression of angiotensin II type 1 receptor mRNA and the relationship between angiotensin II receptor mRNA level and physiological responsiveness in rat aortic smooth muscle cells in primary culture. Angiotensin II (1 microM) induced a time- and dose-dependent transient decrease in the level of angiotensin II receptor mRNA. The maximal decrease (50 +/- 13% of control) occurred at 6 h, followed by a gradual return to the control level within 24 h. H-7 (30 microM), a relatively specific protein kinase C inhibitor, inhibited decrease in the expression of angiotensin II receptor mRNA induced by 6 h angiotensin II treatment, while 6 h stimulation by 0.3 microM phorbol 12-myristate 13-acetate also induced a decrease (35 +/- 8% of control) in the expression of angiotensin II receptor mRNA. An increase in cellular cyclic AMP induced by 10 microM forskolin plus 10 microM 3-isobutyl-1-methyl-xanthine, decreased the angiotensin II receptor mRNA level to 50 +/- 13% of the control at 6 h and increased it to 219 +/- 39% of the control at 48 h of treatment. Angiotensin II-induced decrease and cyclic AMP-induced increase in the expression of angiotensin II receptor mRNA were accompanied by a reduction and enhancement in [Ca2+]i transients induced by angiotensin II, respectively. In contrast with angiotensin II receptor mRNA level (102 +/- 8% of control), the [Ca2+]i transients were markedly decreased in angiotensin II plus H-7 treated cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Identification of the 23 kDa subunit of tau protein kinase II as a putative activator of cdk5 in bovine brain

Tau protein kinase II (TPKII) was reported previously to be composed of a neuron-rich cdc2-related kinase (PSSALRE/cdk5) and 23 kDa subunit. Here we show that the 23 kDa subunit is a putative activator for the kinase activity. Amino acid sequence analysis revealed that the protein was novel and included a partial similarity of amino acids to a cyclin box important for the interaction with cdc2-related kinase. These results suggest that the 23 kDa subunit, but not cyclin, activates cdk5 in neuronal cells, which no longer exhibit cell cycling but are terminally differentiated cells.

[Prospective study on the influence of social activity on development of dementia in the neurologically normal elderly]

We investigated the rate of development of dementia in 84 neurologically normal elderly subjects living in an old-age home (30 subjects, mean 77.2 years) or their own home 954, 73.7) prospectively. We examined cerebral blood flow (CBF), Hasegawa's scale (HS) and Kohs' block design test 6 to 9 years before this study (1991). HS and Kohs' IQ were significantly lower in the old-age home group than that in their own home group at that time. However, there were no demented subjects. Mortality was 21%, and we confirmed 9 dementia and 6 stroke cases during the period of observation. Twenty-seven percent of the old-age home group showed dementia in 1991. This rate was significantly higher than that for the elderly living in their own home (6.7%). Occurrence of stroke was also significantly higher in the former group than in the latter group. The subjects who developed stroke during observation showed a high incidence of dementia. Mean CBF measured on the first examination was significantly lower in dementia cases with stroke than in dementia cases without it. We performed MRI in 4 demented cases in 1991 (Fig. 1). Two cases showed no significant lesions and the other cases showed cerebral infarction which could cause dementia. These results indicate that life style and social environment may have significant effect on aging of the brain and on development of dementia in the elderly.

[A case of paraventricular anaplastic astrocytoma following radiation therapy for craniopharyngioma]

A 20-year-old man received 60 Gy of radiation therapy after partial removal of craniopharyngioma. The patient had been well and follow-up CT scans did not show any aggravation for 16 years. Since his activity gradually diminished, he underwent an MRI at the age of 36 which revealed an abnormal mass on the corpus callosum. The mass lesion progressively enlarged thereafter, and was diagnosed as anaplastic astrocytoma by a stereotactic biopsy. He was treated with interferon, however, died at the age of 37. Review of literature disclosed 19 other cases of glioma following radiation therapy for sellar/parasellar tumors. Characteristic features of these cases included 1) lowness of age compared to common glioma cases, 2) tendency to be malignant, 3) tendency to occur in areas where significant doses of radiation had been received previously.

Evaluation of mixed chimerism by two-step polymerase chain reaction amplification of hypervariable region MCT118 after allogeneic bone marrow transplantation

We assessed the origin of peripheral blood cells and bone marrow cells of 92 samples obtained from 19 patients after allo BMT by two-step polymerase chain reaction (PCR) amplification of MCT118, one of the variable number of tandem repeat regions (VNTR) which has a different length in 19 of 32 sibling pairs examined, that can detect the DNA pattern of a minor cell population of only 1% without using radioisotopes. Mixed chimerism (MC) was detected in the hematopoietic cells of four patients. Two patients who showed progressive MC developed relapse of leukemia 3 months and 4 months after the detection of MC, and two patients died with bone marrow hypoplasia 61 days and 7 months after BMT. These data suggest the clinical importance of analyzing the correlation of MC and clinical complications after BMT by this method, which can be used to monitor MC in about two thirds of allo BMT patients with an adequate sensitivity.

Sensitivity of G-protein involved in endothelin-1-induced Ca2+ influx to pertussis toxin in porcine endothelial cells in situ

1. We designed a new method to determine quantitatively the intracellular Ca2+ concentration ([Ca2+]i) in endothelial cells in situ, using front-surface fluorometry and fura-2-loaded porcine aortic valvular strips. Using this method, we investigated the characteristics of the G-protein involved in endothelin-1 (ET-1)-induced changes in [Ca2+]i of endothelial cells in situ. 2. Endothelial cells were identified by specific uptake of acetylated-low density lipoprotein labelled with 1,1'-dioctadecyl-3,3,3',3'-tetramethyl-indocarbocyanine perchlorate (DiI-Ac-LDL). Double staining with DiI-Ac-LDL and fura-2 showed that the valvular strip was covered with a monolayer of endothelial cells and that the cellular component which contributed to the fura-2 fluorescence, [Ca2+]i signal, was exclusively endothelial cells. 3. ET-1 (10(-7) M) induced an elevation of [Ca2+]i consisting of two components: the first was a rapid and transient elevation to reach a peak, followed by a second, sustained elevation (the second phase). The first phase was composed of extracellular Ca(2+)-independent and -dependent components, while the second phase was exclusively extracellular Ca(2+)-dependent. The extracellular Ca(2+)-independent component of the first phase was due to the release of Ca2+ from intracellular storage sites. The second phase and part of the first phase of [Ca2+]i elevation were attributed to the influx of extracellular Ca2+. The Ca2+ influx component was completely inhibited by 10(-3) M Ni2+ but was not affected by 10(-5) M diltiazem. 4. Pertussis toxin (IAP) markedly inhibited the extracellular Ca2+-dependent elevation of [Ca2+]j, but had no effect on the extracellular Ca2+-independent elevation of [Ca2+], caused by ET-1 (10-7M).5. Bradykinin (10-7 M) or ATP (10- 5M) elevated [Ca2+]i and these responses also consisted of extracellular Ca2+-independent and extracellular Ca2+-dependent components. IAP had no effect on either component of the [Ca2+]i elevation induced by bradykinin or ATP.6. From these findings we conclude that, in porcine endotheliel cells in situ, ET-1 elevates [Ca2+]i as are result of a Ca2+ influx component from the extracellular space and release of intracelluarly stored Ca2+ .The Ca2+ influx is regulated by an IAP-sensitive G-protein, while the release of Ca2+ from the intracellular store is not.

Failure of combination therapy with recombinant granulocyte colony-stimulating factor and erythropoietin in myelodysplastic syndromes

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) and erythropoietin (rhE-PO) were used to treat ten patients with myelodysplastic syndromes (MDS). None of the patients showed a favorable response in erythrocyte and platelet counts following 10 weeks' treatment, although favorable responses in neutrophil counts were observed in eight of ten patients (80.0%) and in seven of eight patients (87.5%) following 2 weeks' and 10 weeks' treatment, respectively. However, one patient with refractory anemia had a delayed favorable response in erythrocyte and neutrophil counts at week 14 in spite of the cessation of combination therapy at week 10. These results indicate that combination therapy with rhG-CSF and rhEPO is not beneficial to patients with MDS, based on the presently used protocol.

Treatment and prevention of tethered and retethered spinal cord using a Gore-Tex surgical membrane

The incidence of the tethered cord syndrome after repair of spinal dysraphism is not insignificant. A retethered spinal cord may also develop after an untethering operation. In order to treat and/or prevent the tethered and retethered spinal cord, the authors developed and successfully used a new method in 12 cases. After complete release and reconstruction of the spinal cord, a Gore-Tex surgical membrane was placed over the cord and fixed to the lateral dural surface with stay sutures. During a postoperative follow-up period ranging from 23 months to 7 years, no further neurological deterioration was observed in the 12 patients and magnetic resonance imaging studies showed no adhesion of the spinal cord to the operative site. It is concluded that this simple new method is effective for the treatment and prevention of tethering and/or retethering of the spinal cord, although a longer follow-up study is required.

A preoperative assessment of adjacent organ invasion by stomach carcinoma with high resolution computed tomography

Adjacent organ invasion by stomach carcinoma on computed tomography (CT) was studied. CT images of tumors and their adjacent organs, whose invasion was assessed at surgery, were retrospectively analyzed in 51 gastric cancer patients. An absence of fat planes or an irregularity of the border between the tumor and adjacent organs was not found to be significantly related with invasion. The mean densities of the region of interest (ROI) set at the border were greater at the invasion sites (60.0 +/- 38.1) than at noninvasion sites (35.6 +/- 55.5) (P < 0.05). The standard deviation of the densities in the ROI was not affected by invasion. The discriminant function determined invasion to the pancreas, liver, and colon with an accuracy of 75%, 61%, and 78%, respectively. In diagnosing the invasion of stomach cancer on CT, the conventional criteria were not practical, while a quantitative analysis of the density in the ROI with high resolution CT was considered to improve the accuracy.

[Experience with surgery for metachronous double cancer originated from thymus and lung]

A case with thymic cancer who developed pulmonary cancer ten years after the initial surgery was reported. A 50-year-old man was admitted to our hospital due to SVC syndrome. Chest X-ray examinations including venogram showed a mass lesion at the superior mediastinum. The patient underwent surgical removal and reconstruction of SVC, followed by radio-chemotherapy. The histologic diagnosis was thymic squamous cell carcinoma. He was admitted to our hospital again ten years after the initial surgery under the diagnosis of pneumonia. Bronchoscopic examination revealed nodular lesions at the right upper lobe bronchus and lower lobe bronchus, those lesions were diagnosed with squamous cell carcinomas cytologically. Right pneumonectomy was performed and the diagnosis was confirmed pathologically. Postoperative course was uneventful as of 10 months after the operation. It was concluded that this case showed metachronous double cancer of the thymus and the lung, as well as synchronous multiple bronchogenic carcinomas, which, to our knowledge, has never been reported yet.