MR Imaging Findings of Carcinoma Ex Pleomorphic Adenoma Related to Extracapsular Invasion and Prognosis

BACKGROUND AND PURPOSE

MR imaging can reflect the pathologic progression of carcinoma ex pleomorphic adenoma (CXPA). This study aimed to identify the imaging findings related to extracapsular invasion of CXPA. Additionally, the pathologic background of these findings was investigated.

MATERIALS AND METHODS

This retrospective study included 37 patients with histologically confirmed CXPA. Three radiologists independently evaluated whether the CXPA showed the following characteristic MR imaging findings: border, capsule, the corona sign on fat-saturated T2WI and contrast-enhanced fat-saturated T1WI, and the black ring sign. The corona sign appeared larger on fat-saturated and/or contrast-enhanced fat-saturated T1WI than on T1WI. The black ring sign was defined as an intratumoral nodule with a thick low-intensity rim on T2WI. Interreader agreement of the visual assessment was performed using κ analysis, and MR imaging and histopathologic findings were also correlated. Kaplan-Meier survival and the log-rank test were used to estimate the 3-year disease-free survival.

RESULTS

MR imaging findings, especially peritumoral findings, showed a significant difference between invasive and noninvasive CXPA. The reliability was poor for the border and capsule. In contrast, it was good for the corona sign on fat-saturated and contrast-enhanced fat-saturated T1WI and the black ring sign. Pathologically, the corona sign reflected the invasiveness of the tumor and inflammatory cells, while the black ring sign reflected hyalinization or fibrosis. The corona sign also showed a significant difference in the 3-year disease-free survival.

CONCLUSIONS

MR imaging findings, including the corona and black ring signs, reliably differentiated invasive and noninvasive CXPA. The corona sign can be used as a prognostic factor for CXPA.

P6415Combined assessment of contrast-enhanced ultrasound of carotid plaque and carotid intima-media thickness improves the prediction of future coronary events in patients with coronary artery disease

Background

This study examined whether combined ultrasound assessment of plaque size and intraplaque neovascularization in the carotid artery had an additive effect for predicting coronary events in patients with coronary artery disease (CAD).

Methods

CEUS of the carotid plaques using perfluorobutane microbubbles as an ultrasound contrast agent and Ultrasound assessment of carotid plaque maximum intima-media thickness (max IMT) was performed in 221 patients with CAD and carotid plaque IMT over 2mm. Intraplaque neovascularization was identified on the basis of microbubbles within the carotid plaque and graded as: G0, not visible; G1, moderate; or G2, extensive microbubbles. All study patients were followed up prospectively for 5 years or until the occurrence of a cardio-vascular event.

Result

During the follow-up period, 53 coronary events (9 cardiac deaths, 44 ACSs) were occurred. Multivariate Cox hazards analysis showed that max IMT and CEUS grade were independent predictors of coronary events (HR 1.59, 95% CI 1.15–2.21 p=0.005 and HR 2.26, 95% CI 1.52–3.36 p<0.01) that were independent of age, gender, diabetes and LDL-C levels. C-statistics for logistic models predicting future coronary events using conventional risk factors with or without the addition of max IMT alone, CEUS grade alone, and both max IMT and CEUS grade in combination (area under the ROC curve; 0.55,0.61,0.69 and 0.71, respectively). The addition of the plaque enhanced intensity to traditional risk factors resulted in net reclassification improvement (NRI) and integrated discrimination improvement (IDI) (NRI 0.42, p=0.002; and IDI 0.04, p=0.002).

CEUS grade and ROC curve for 3models

Conclusions

Combined ultrasound assessment of carotid plaque IMT and intraplaque neovascularization has an additive value on the prediction of coronary events.

P3448Influence of severity of pectus excavatum as indicated by the Haller Index on actual heart compression and ECG findings

Background

Pectus excavatum (PEX) is a depression of the sternum relative to the costal cartilages. The Haller index (HI) is an anatomical indicator of the severity of PEX that is calculated from CT.

Purpose

We evaluated the influence of anatomical severity of PEX as indicated by HI on the severity of actual heart compression and ECG findings

Methods

A total of 28 patients (23 males; 20±19 years) with PEX underwent unenhanced CT and ECG. On CT, HI and degree of compression of right (RA) and left atria (LA) were evaluated simultaneously.

Results

As indicated by CT, the mean HI was 5.80±2.34. We observed 7, 15, 5, and 1 patient with none, mild, moderate, or severe RA compression, respectively. In addition, we observed 8, 13, 4, and 3 patients with none, mild, moderate, or severe LA compressions, respectively. The mean HI was calculated as 4.28±0.92, 5.40±2.01, 6.85±1.81, and 9.61±0.00 in patients with none, mild, moderate, or severe RA, respectively, and the findings were significant (P=0.021). The mean HI was calculated as 4.17±0.91, 5.97±2.23, 5.95±1.51, and 6.69±2.93 in patients with none, mild, moderate, or severe LA compression, respectively, although the findings were not significant (P=0.145). On ECG, a P wave with a negative portion >1 mm in depth and >40 ms in duration in the V1 lead, complete or incomplete right bundle branch block (RBBB), sinus arrhythmia, or right-axis deviation of a QRS wave were diagnosed in 23, 10, 8, and 6 patients, respectively. The HI between patients with (n=23) and without (n=5) a negative portion of the P wave in the V1 lead showed a significant difference (6.45±2.43 vs. 4.62±1.68; P<0.05). The correlation coefficient between absolute values of the maximum negative portion of the P wave in the V1 lead and HI was 0.36 (n=28). The HI between patients with and without a complete or incomplete RBBB showed a significant difference (6.98±2.43 vs. 5.14±2.07; P<0.05). The HI between patients with and without a sinus arrhythmia did not show a significant difference (5.45±2.66 vs. 5.94±2.25). The HI between patients with and without a right axis deviation on a QRS wave also did not show a significant difference (4.76±1.53 vs. 6.08±2.64). The inter-observer agreement of HI between the two observers was 0.978.

Haller index and heart compression on CT

Conclusion

In patients with PEX, compression of RA on CT, a negative portion of the P wave in V1, complete or incomplete RBBB, sinus arrhythmia, and a right axis deviation on a QRS wave are common. The degree of compression of RA on CT, negative portion of the P wave in the V1 lead and complete or incomplete RBBB on ECG are associated with anatomical severity as indicated by the HI. However, our results showed that HI severity was unrelated to either the degree of compression of LA on CT, or sinus arrhythmia and right-axis deviation of the QRS wave on ECG. These observations may be due to variation of location of maximum sternum depression, such as high- or low-positioned dominant-type compressions.

P1227Remnant lipoprotein is a residual risk of future cardiovascular events in patients with stable coronary artery disease and on statin LDL-cholesterol levels less than 70 mg/dl

Background

Recent guidelines recommend a target of low density lipoprotein cholesterol (LDL-C) <70 mg/dL in patients at very high risk of cardiovascular disease (CVD). However, a considerable residual risk of CVD persists despite achievement of the LDL-C goal on statin treatment.

Purpose

This study examined the predictive value of remnant lipoprotein levels for cardiovascular events (CVE) in patients with stable coronary artery disease (CAD) and LDL-C levels <70 mg/dL on statin treatment.

Methods

Serum levels of remnant lipoproteins (remnant-like lipoprotein particles cholesterol; RLP-C) were measured by an immunoseparation method in 247 consecutive patients with CAD who had on-statin LDL-C levels <70 mg/dL. All the patients were followed prospectively for a period of ≤60 months or until the occurrence of the primary composite endpoint of cardiac death, nonfatal myocardial infarction, unstable angina requiring coronary revascularization, worsening heart failure, peripheral artery diseases requiring endovascular or surgical intervention, aortic events, and ischemic stroke.

Results

During a mean follow-up period of 38 months, 33 CVEs occurred. Kaplan-Meier estimates in time-to-first-event analysis demonstrated that higher RLP-C levels (>3.9 mg/dL, determined by ROC-curve) resulted in a significantly higher probability for the primary endpoint than did lower RLP-C levels (<3.9 mg/dL) (p<0.01 by log-rank test). Stepwise multivariate Cox proportional hazard analysis showed that RLP-C was a significant predictor of the primary endpoint after adjustment for known risk factors and lipid variables including triglycerides (TG), and total apolipoprotein B (ApoB) (HR 1.62, 95% CI 1.26–2.07, p<0.01). The c-statistics showed that addition of RLP-C had a significant incremental effect on the predictive value of traditional risk factors (area under curve; traditional risk factors: 0.68 vs. traditional risk factors + RLP-C: 0.77, p=0.02). Category-free NRI and IDI demonstrated the additive value of RLP-C to the traditional risk factors plus non-high-density lipoprotein (HDL)-C and ApoB levels (NRI 0.52, p<0.01; IDI 0.06, p<0.01).

Conclusions

RLP-C levels are a residual risk factor for future CVEs in patients with CAD and on-statin LDL-C <70 mg/dL.

P2706Persistent impairment of coronary endothelial vasomotor responses is related to atheroma plaque progression in the infarct-related coronary artery of AMI survivors

Background

Although coronary endothelial vasomotor dysfunction predicts future coronary events, there are few human studies showing the relationship between endothelial vasomotor dysfunction and atheroma plaque progression in the same coronary artery.

Purpose

This study examined whether endothelial vasomotor dysfunction is related with atheroma plaque progression in the infarct-related coronary artery of ST-segment elevation myocardial infarction (STEMI) survivors using serial assessment of coronary plaque size with intravascular ultrasound (IVUS) and coronary vasomotor responses to acetylcholine (ACh).

Methods

This study included 50 patients with a first acute STEMI due to occlusion of left anterior descending coronary artery (LAD) and successful reperfusion therapy with percutaneous coronary intervention (PCI). IVUS and vasomotor response to ACh in the LAD were measured within 2 weeks after AMI (1st test) and repeated 6 months (2nd test) after AMI under optimal anti-atherosclerotic therapies. The impairment of vasomotor response to ACh was defined as <10% of the responses to ACh in 25 control subjects.

Results

Percent atheroma volume (PAV) and total atheroma volume (TAV) in the LAD progressed over 6 months of follow-up in 18 and 14 patients, respectively. Epicardial coronary artery dilation and coronary blood flow increase in response to ACh were persistently impaired at both the 1st and 2nd tests in 18 and 19 patients. In logistic regression analysis, the progression of PAV and TAV was significantly associated with patients with the persistent impairment of epicardial coronary diameter and blood flow response to ACh (PAV, OR, 6.2 [95% CI, 1.4–28], P=0.02 and 4.3 [1.2–16], P=0.03, respectively. TAV, 6.0 [1.4–26], P=0.02 and 5.5 [1.4–21], P=0.01, respectively). The progression of PAV and TAV had no significant association with the coronary vasomotor responses to ACh at the 1st test, traditional risk factors, PCI-related variables, medications, and the coronary vasomotor responses to sodium nitroprusside, an endothelium-independent vasodilator.

Conclusions

Persistent impairment of endothelial vasomotor function in the conduit arterial segment and the resistance arteriole was related to atheromatous plaque progression in the infarct-related coronary arteries of STEMI survivors despite optimized anti-atherosclerotic therapies.

Acknowledgement/Funding

None

Evaluation of cervical myelopathy using apparent diffusion coefficient measured by diffusion-weighted imaging

BACKGROUND AND PURPOSE

Intramedullary high signal intensity on T2-weighted imaging was frequently observed in patients with CSM, although this finding does not well correlate with severity or prognosis of CSM. Instead of this nonquantitative information, another measure for CSM is desired. The work was focused primarily on assessing the relationships between ADC values and clinical and radiologic severity for the diagnosis of CSM.

MATERIALS AND METHODS

The relationship between ADC values measured in the spinal cord at 322 intervertebral levels of 66 patients and clinical factors were analyzed.

RESULTS

ADC values in the spinal cord significantly increased with the degree of spinal cord compression and decreased with time after decompression surgery. Patients with higher ADC values had lower preoperative JOA scores and tended to show poorer clinical recovery.

CONCLUSIONS

ADC values appear to indicate the severity of spinal cord compression and clinical recovery after decompression surgery, so spondylotic myelopathy may partly be predicted preoperatively by using ADC values.

Head and neck MRI of Kimura disease

OBJECTIVES

The purpose of our study was to describe the MR appearance of Kimura disease and to interpret the differences in appearance from malignant parotid gland tumours.

METHODS

MR studies of seven patients with Kimura disease were reviewed. The MR studies included T(1) weighted, T(2) weighted, short tau inversion-recovery, diffusion-weighted (DW) and dynamic contrast-enhanced imaging.

RESULTS

Typical Kimura disease featured subcutaneous lesions, continuously infiltrated parotid lesions from the subcutaneous lesions with or without intraparotid lymphadenopathies, and reactive cervical lymphadenopathies. The subcutaneous lesions showed gradual upward enhancement on dynamic contrast-enhanced MR images. Reactive lymph nodes showed early enhancement on contrast-enhanced MR images and marked high intensity and low apparent diffusion coefficient values on DW images.

CONCLUSION

An indication for making the diagnosis of Kimura disease should be the subcutaneous tissue of the head and neck showing gradual upward enhancement on dynamic contrast-enhanced MRI and a lack of high intensity on DW images, associated with reactive lymph nodes.

Diagnostic value of spinal MR imaging in spontaneous intracranial hypotension syndrome

BACKGROUND AND PURPOSE

Spontaneous intracranial hypotension (SIH) presents with orthostatic headache, and the diagnosis is made on the basis of low CSF pressure and brain MR imaging findings characteristic of the disorder. However, a broad spectrum of symptoms and MR imaging findings of SIH is recognized, and some cases have no typical MR imaging abnormalities. SIH is believed to be caused by CSF leakage from the spinal dural sac, whereas the usefulness of MR imaging of the spine remains unclear. Our aim was to elucidate the diagnostic value of brain and spinal MR imaging

MATERIALS AND METHODS

The sensitivities for the detection of SIH were retrospectively evaluated in 18 patients with SIH treated in our institutions between January 1998 and August 2007.

RESULTS

Brain MR imaging detected abnormalities in 15 of the 18 patients (83%): diffuse pachymeningeal enhancement in 15 (83%), descent of the cerebellar tonsil in 13 (72%), brain stem sagging in 13 (72%), enlargement of the pituitary gland in 12 (67%), and subdural fluid collection in 13 (72%). Spinal MR imaging detected abnormalities in 17 of the 18 patients (94%): distention of the epidural veins in 14 (78%), epidural fluid collection on fat-saturated T2-weighted images in 16 (89%), and abnormal visualization of the nerve root sleeve in only 1 (6%). The sensitivity for SIH was 83% for brain MR imaging and 94% for spinal MR imaging.

CONCLUSIONS

Spinal MR imaging is useful for the diagnosis of SIH, especially in the early stage.

Neurophysiological analysis of visuo-vestibular conditioning in Lymnaea stagnalis

Lymnaea are capable of learning an association between light and rotation. The conditioning paradigm to produce this association and the unconditioned escape response are the same for both Lymnaea and Hermissenda, but the underlying neural mechanisms appear to differ between the two species due to differences in the organization and function of their visuo- and vestibular-sensory systems. The RPeD11 interneuron in Lymnaea controls withdrawal behavior. We analyzed the electrophysiologic characteristics of the RPeD11 and observed an increase in cell excitability; that is, spontaneous activity of the postsynaptic potential in the RpeD11 was increased in conditioned animals after learning acquisition.

Relationship between developmental synaptic modulation and conditioning-induced synaptic change in Lymnaea

Though adult Lymnaea are bimodal breathers, young animals breathe mainly through the skin and adults through the lung. Operant conditioning changes adult breathing behavior from aerial to cutaneous. We hypothesized that this behavioral change is caused by alterations in the neuronal circuit during both development and conditioning. We focused our study on whether the synaptic connection between RPeD1 and RPA6 neurons is modulated during development and conditioning. Our findings indicated that the RPeD1 has an excitatory monosynaptic contact with the RPA6 in young naive and operantly-conditioned adult animals. The relationship of this contact was well correlated with their respiratory behavior.

Immunohistological studies on the distribution of learning-related peptides in the central nervous system of conditioned Lymnaea

Behavioral conditioning in Lymnaea increased the amount of immunolabeling in the central nervous system for the memory-associated protein calexcitin. The staining level of anti-calexcitin positive neurons was always stronger in conditioned animals than in naive animals. In the visuo-vestibular conditioned animals, right-parietal and visceral group neurons as well as withdrawal-related neurons were positively stained with anti-calexcitin antibody. In taste-aversion conditioned animals, right-parietal visceral G-group neurons and withdrawal-related neurons were selectively stained. These neurons are candidate neurons for modulation by these conditioning paradigms.

Decreased diameter of the optic nerve sheath associated with CSF hypovolemia

The subarachnoid space around the optic nerve can be detected by fat-saturated T2-weighted MR imaging of the orbit, and dilation of this space reflects increased intracranial pressure. We examined 3 patients with CSF hypovolemia with MR imaging of the orbit and measured the optic nerve sheath diameter before and after treatment. We showed that the subarachnoid space is decreased in patients with CSF hypovolemia and the usefulness of this finding.

Tracer clearance in radionuclide cisternography in patients with spontaneous intracranial hypotension

We semiquantitatively analysed radionuclide cisternography in three patients with spontaneous cerebrospinal fluid (CSF) leakage diagnosed by typical symptoms and magnetic resonance imaging findings before and several months after treatment with epidural blood patch. Radioactivity in the whole CSF space was measured immediately after and at 1, 5, 7 and 24 h after intrathecal injection of (111)In-diethylenetriaminepentaacetic acid (DTPA). Initial findings included the vague appearance of leakage in the thoracic spine in two patients, early bladder filling at 1 h in one and a lack of tracer filling into the high cranial convexity in all three. The radioactivity count rapidly decreased within several hours after injection and reached 20% of the initial value at 24 h. In contrast, no rapid decrease was observed after treatment and more than 50% of tracer remained at 24 h after injection. Semiquantitative analysis of tracer clearance may provide additional information in the diagnosis of CSF leakage, especially with no obvious qualitative findings.

Acceleration of de novo Cholesterol Synthesis in the Epidermis Influences Desquamation of the Stratum Corneum in Aged Mice

Cholesterol, a component of intercellular lipids, is important for stratum corneum (SC) homeostasis, including its barrier function and desquamation. However, cholesterologenesis in the epidermis decreases under basal conditions with aging. We found that the number of horny layers in murine SC increased with the decrease of desquamation in the outermost corneocytes associated with aging. The cholesterol content decreased and the cholesterol sulfate content increased in the horny layer with aging, which resulted in an increase in the ratio of cholesterol sulfate to cholesterol. Moreover, we investigated the effects of accelerated cholesterologenesis on desquamation in aged murine skin following topical application of mevalonic acid. The ratio of cholesterol sulfate to cholesterol in aged murine SC significantly decreased following topical treatment with mevalonic acid, which resulted from an increase in cholesterol content via the acceleration of cholesterologenesis. Treatment with mevalonic acid also significantly reduced the number of cell layers in the SC along with the acceleration of desquamation, as measured by desmoglein I content, corneocyte surface area and proteinase activity. These results indicate that an improvement in the ratio of cholesterol sulfate to cholesterol content by de novo cholesterologenesis may be important for desquamation of the SC in aged epidermis.

Intramedullary spinal cord germinoma expresses the protooncogene c-kit

A 33-year-old woman first noticed numbness in the both lower extremities and the numbness gradually extended up to the thorax. Magnetic resonance (MR) imaging demonstrated a mass with moderate and heterogeneous enhancement and peritumoural intramedullary cysts in the spinal cord at the T-1 to T-3 levels. The tumour was explored partially and intra-operative pathological examination demonstrated the so-called "two-cell pattern" typical of germinoma. The margin of the tumour was not clear. Histological examination showed germinoma with strong c-kit protein expression on the tumour cell surface. Chemotherapy and radiation therapy were given following surgery. Her neurological deficits were improved but not resolved.

Effects of glycolic acid on desquamation-regulating proteinases in human stratum corneum

In order to investigate the mechanism of glycolic acid (GA) function in human stratum corneum, we monitored changes in cathepsin D-like (CD) and chymotrypsin-like (SCCE) proteinases for 3 weeks following topical GA application (50% w/v, pH 0.9) for 30 min to human skin. In the early phase, weakened stratum corneum cohesion in the lower layers was observed on day 2 and the amount of active CD in the upper layer of the stratum corneum was significantly decreased from 30 min until day 2, whereas that in the lower layer remained normal. In contrast, the amount of active SCCE showed no change during the experimental period. The surface pH of the stratum corneum drastically decreased to pH 2 at 30 min and slightly recovered to around pH 3 until 1 day after treatment. From 9 to 19 days, a decrease in corneocyte cell area and a remarkable long-term increase in the amount of active CD in the upper layer were observed. In an in vitro study, the activities of desquamation-regulating proteinases were shown to have remarkably increased at around pH 3, due to activation of CD at its optimal pH. These results suggest that GA functions via at least two different mechanisms, acute activation of CD in the lower layer by acidification around pH 3, along with inactivation of CD in the upper layer, and long-term enhancement of de novo CD production in the few weeks following GA treatment.

Cathepsin D, but not cathepsin E, degrades desmosomes during epidermal desquamation

BACKGROUND

We previously reported that an ambient aspartic proteinase is crucial to desquamation of the stratum corneum at pH 5. Identification of this aspartic proteinase by using enzyme inhibitors suggested it to be cathepsin D, although we could not exclude cathepsin E.

OBJECTIVES

To determine the identity of this aspartic proteinase and its distribution within the stratum corneum.

METHODS

We measured enzyme activities of cathepsin D and cathepsin E in the salt and detergent extracts from callus stratum corneum, using a fluorogenic peptide as a substrate and comparing the effect of addition of Ascaris pepsin inhibitor (specific for cathepsin E) with that of pepstatin A (which inhibits both cathepsin D and cathepsin E). Both enzymes were then extracted and purified from plantar stratum corneum samples and identified by Western blotting. Immunofluorescence microscopy was used to investigate the localization of proteinases within human plantar stratum corneum sample sections.

RESULTS

We found that 20% of total aspartic proteinase activity could be attributed to cathepsin E, the remainder to cathepsin D. Two subunits of cathepsin D were identified, a mature active form at 33 kDa and an intermediate active form at 48 kDa; cathepsin E was also identified at 48 kDa, although in a stained band 10-fold weaker in the immunoblot. Immunofluorescence microscopy showed the antibody to cathepsin D to be localized in the lipid envelopes of the stratum corneum, whereas that to cathepsin E stained the tissue diffusely. The labelling for cathepsin D was similar to that observed for desmosomes, and immunoelectron microscopy confirmed that cathepsin D was present on desmosomes. On the other hand, cathepsin E occurred intracellularly within the squames.

CONCLUSIONS

We conclude that cathepsin D, and not cathepsin E, causes desquamation by degrading desmosomes.

Suppression of melanogenesis by induction of endogenous intracellular metallothionein in human melanocytes

Nitric oxide (NO) is a potent intercellular mediator of melanogenesis, whereas metallothionein (MT) is an inducible intracellular antioxidant that has been reported to scavenge NO. We investigated the existence and induction of MT in melanocytes, and its inhibitory effect on NO-induced melanogenesis. The expression of MT was detected in melanocytes, however, at a lower level than in keratinocytes, and its induction was possible by the addition of zinc chloride. Further, an NO-stimulated increase of tyrosinase activity in melanocytes was remarkably suppressed, when MT was induced prior to NO stimulation. Melanogenesis was also suppressed, when dexamethasone was used to induce MT. However, an NO-stimulated increase of tyrosinase expression was not suppressed at the gene and protein level, when MT was induced in melanocytes. The same suppressive effect of melanogenesis was also observed, when alpha-melanocyte-stimulating hormone or endothelin-1 was used as a stimulator. Because these results implied a mechanism other than NO scavenging to explain the suppressive effect of MT induction on melanogenesis, the direct inhibition of tyrosinase by MT was examined. Melanosome fractions were prepared from melanocytes, whose melanogenesis was suppressed by the induction of MT. Tyrosinase suppression was observed in the melanosome fractions, which was neutralized by the addition of anti-MT antibody. These results suggest that MT induction may be effective to suppress melanogenesis stimulated by NO as well as other melanogens, and these suppressive effects might be due to a direct inhibition of tyrosinase activity in melanosome and not a scavenging effect of NO.

Coxsackievirus and adenovirus receptor (CAR)-positive immature osteoblasts as targets of adenovirus-mediated gene transfer for fracture healing

Adenovirus vectors are expected to be a powerful tool for gene therapy to treat severe fractures. Adenovirus invades cells through binding to the coxsackievirus and adenovirus receptor (CAR) on the cell membrane. CAR expression is low in normal adult animals, but it is induced on regenerating cells in some experimental models. We made a rib fracture model in mice and evaluated the histological changes and CAR mRNA expression by RT-PCR 1, 5, 10, 14, and 21 days after the fracture. CAR mRNA was expressed exclusively in the fractured ribs at each time point, but not in the normal ribs. We detected the CAR protein immunohistochemically in fibroblast-like cells in the fracture callus on days 10 and 14 after fracture. In situ hybridization showed that these fibroblast-like cells expressed mRNA of type I collagen and osteopontin, but not osteocalcin, defining the cells as immature osteoblasts. We then transferred small doses (10(4)-10(8) PFU) of lacZ-expressing adenovirus vector into immature osteoblasts on day 14. beta-galactosidase was detected only on the immature osteoblasts at every dose. Immature osteoblasts play an important role in the matrix replacement step in fracture healing. CAR-mediated gene transfer into immature osteoblasts can be reasonable for adenovirus-mediated treatment of fracture healing.

Anatomical variations of the ten triangles around the cavernous sinus

The dimensions of the 10 triangles around the cavernous sinus were measured to define the anatomical characteristics of the triangles and to compare their consistency in shape and area. Twelve tissue blocks containing the bilateral cavernous sinuses and medial two-thirds of the middle cranial fossae were obtained from Japanese adults at autopsy, fixed to a stereotactic frame, and examined with an operative microscope. The dimensions of each triangle were measured with calipers and compared, based on the same point and border. The anteromedial triangle and the superolateral (Parkinson's) triangle were more consistent in shape than the paramedial and oculomotor triangles, but the oculomotor triangle was larger in area than these other triangles. The posteromedial (Kawase's) triangle was more consistent in shape and larger than the anterolateral, lateral, and the posterolateral (Glasscock's) triangles. The anteromedial and superolateral (Parkinson's) triangles are important for the combined epi- and subdural approach to cavernous sinus lesions. The posteromedial (Kawase's) triangle is important for gaining access to the posterior cranial fossa from the middle cranial fossa.

Statistical analysis of factors affecting the outcome of patients with ruptured distal anterior cerebral artery aneurysms

The clinical factors affecting the outcome of patients with ruptured distal anterior cerebral artery (ACA) aneurysms were analyzed using multiple logistic regression analysis. The medical records were reviewed of 52 patients (57 aneurysms) with ruptured distal ACA aneurysms operated on by the same neurosurgeon over 25 years. The standard policy was early surgery for patients in Hunt and Kosnik grades I to IV. Age, sex, Hunt and Kosnik grade, timing of operation, size of aneurysms, number of aneurysms, association of intracerebral haemorrhage (ICH), intraventricular haemorrhage, and azygos ACA, use of temporary clipping, occurrence of premature rupture, and presence of psychiatric change were investigated. Univariant analysis disclosed that clinical grade (P = 0.0006), size of aneurysm (P = 0.005), and size of ICH (P = 0.012) affected the outcome of patients. Multiple logistic regression analysis found that Hunt and Kosnik grade (P = 0.010) and timing of operation (P = 0.033) affected the outcome. There was no significant relationship between long-term outcome and clinical factors, although a close relationship was found with Hunt and Kosnik grade (P = 0.071). Clinical grade and timing of the operation affected the outcome of patients with ruptured distal ACA aneurysms. Patients harboring ICH of over 3 cm diameter in poor grades should also be carefully treated.

Involvement of nitric oxide in UVB-induced pigmentation in guinea pig skin

Ultraviolet (UV) B irradiation evokes erythema and delayed pigmentation in skin, where a variety of toxic and modulating events are known to be involved. Nitric oxide (NO) is generated from L-arginine by NO synthases (NOS). Production of NO is enhanced in response to UVB-stimulation and has an important role in the development of erythema. NO has recently been demonstrated as a melanogen which stimulates melanocytes in vitro, however, no known in vivo data has been reported to support this finding. In this study, we investigated the contribution of NO with UV-induced pigmentation in an animal model using an NOS inhibitor. UVB-induced erythema in guinea pig skin was reduced when an NOS inhibitor, L-NAME (N-nitro-L-arginine methylester hydrochloride), was topically applied to the skin daily, beginning 3 days before UVB-irradiation. Delayed pigmentation and an increased number of DOPA-positive melanocytes in the skin were markedly suppressed by sequential daily treatment with L-NAME. Furthermore, melanin content 13 days after UVB-irradiation was significantly lower in skin treated with L-NAME than in the controls. In contrast, D-NAME (N-nitro-D-arginine methylester hydrochloride), an ineffective isomer of L-NAME, demonstrated no effect on these UV-induced skin responses. These results suggest that NO production may contribute to the regulation of UVB-induced pigmentation.

Up-regulation of tyrosinase gene by nitric oxide in human melanocytes

Ultraviolet light (UV) radiation causes skin-tanning, which is thought to be mediated by stimulating the release of melanogenic factors from keratinocytes as well as other cells. Nitric oxide (NO) has been reported to be generated after UV radiation and to stimulate melanocytes as one of the melanogens. In a previous experiment by another group on melanogenesis induced by NO, increases in both tyrosinase activity and tyrosinase protein levels were observed after daily stimulation of NO for 4 days. In the present study, we investigated tyrosinase gene expression within the first 24 hr of NO-induced melanogenesis. Tyrosinase mRNA expression was found to be induced 2 hr after a single treatment with S-nitroso-N-acetyl-L-arginine. An increase of tyrosinase activity was also detected time-dependently within the 24-hr period, accompanied by an increase of tyrosinase protein levels. The induction of mRNA expression was suppressed by a cyclic guanosine 3',5'-monophosphate (cGMP)-dependent protein kinase (cGMP/PKG) inhibitor. These results suggest that the enhancement of tyrosinase gene expression via the cGMP pathway may be a primary mechanism for NO-induced melanogenesis.

Quantification of relative mRNA expression in the rat brain using simple RT-PCR and ethidium bromide staining

We developed a protocol for quantification of relative gene expression using reverse transcription-polymerase chain reaction (RT-PCR) without the use of radioisotopes, special equipment or extra nucleotide fragments, such as competitors. The relative gene expression of GABA(A) receptor beta(1) subunit (GABA(A)Rbeta(1)) and phospholipase C beta(4) subtype (PLCbeta(4)) in rat cerebrum and cerebellum were determined by comparing the ratio of PCR products generated by linear amplification of the target cDNA segments and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) cDNA segment as a reference. The density of PCR products was measured from digitized images of photographs of ethidium-bromide-stained agarose gels. The linear region of PCR amplification was within the linear range (from 0.3 to 12 ng DNA in a single band) of the detection system. The accuracy of the present method was <2-fold difference in gene expression in a single determination and a 1.5-fold difference was statistically significant after repeated measurements. The estimated relative expression of PLCbeta(4) was significantly higher in cerebellum than cerebrum, and that of GABA(A)Rbeta(1) was the same in these two regions. Using the present method, it is possible to quantify several different subunits and subtypes of known ion channel, neurotransmitter receptor and intracellular signaling enzyme gene families.

Usefulness and pitfalls of intraoperative spinal motor evoked potential recording by direct cortical electrical stimulation

OBJECTIVE

The aim of this study is to investigate the usefulness and problems with spinal motor evoked potential (MEP) recording, especially the reasons for failed recording. We report our personal experience over the last 8 years in patients with lesions adjacent to the primary motor cortex.

METHODS

MEP records of 50 consecutive patients were retrospectively reviewed. MEP was recorded by a catheter electrode inserted in the cervical epidural space. Stimulation electrodes were placed on the cortical surface during surgery. SEP recording was also performed in 29 of 50 patients.

RESULTS

MEP was obtained in 40 cases, and SEP was recorded in all 29 cases. The central sulcus was identified in 93% of patients in whom both MEP and SEP were performed, whereas in only 86% of patients who underwent only MEP. The main reason for MEP failure were inadequate exposure of the motor cortex, pre-existing hemiparesis and technical errors. Postoperative deterioration of motor function was closely related to intra-operative MEP changes.

CONCLUSION

MEP is a useful tool to determine the motor cortex and to predict postoperative motor function. However, precise pre-operative craniotomy planning and combination with intra-operative SEP is essential to reduce the MEP failure.

Enhancing effect of electric stimulation on cytotoxicity of anticancer agents against rat and human glioma cells

Electropermeabilization, or electroporation, has been used to deliver genes or drugs into the cytoplasm through micropores in the cell membrane caused by electric stimulation. The cytotoxic effect of a combination of anticancer agents with electric stimulation on rat C6 and human T98G glioma cells was examined in vitro. Electric pulses of 100 microsec square waves (eight cycles at 1 Hz) at various electric fields were delivered to C6 or T98G glioma cell suspensions in combination with several anticancer agents. Cell growth was evaluated 48-72 h after treatment. Measurement of cell lysis by electric stimulation was used to assess the optimum field strength for electroporation. Electric stimulation enhanced significantly the cytotoxicity of bleomycin to both C6 and T98G cells by more than 1000-fold using an electric field of 1750 V/cm for C6 cells and 1000 V/cm for T98G cells. The enhancement disappeared when bleomycin concentration was reduced to 100 pg/ml. The cytotoxicity of carboplatin was weakly but significantly enhanced by electric stimulation when a high dose of carboplatin was used. However, there was no enhancement of the cytotoxicity of nimustine hydrochloride (ACNU), etoposide, and vincristine. These results indicate that the combination of bleomycin and electroporation is the most potent candidate for electrochemotherapy in vivo.

Chronological changes in MRI findings of spinal dural arteriovenous fistula

BACKGROUND

Intramedullary high-intensity changes on T2-weighted magnetic resonance images (MRI) occur in patients with spinal dural arteriovenous fistulas (AVF). Reduction of the high-intensity area after treatment has been noted; however, there are still questions about whether the change is related to preoperative clinical grade, postoperative improvement, or efficacy of treatment. This study tried to clarify the relationship between chronological changes in the high intensity area with the treatment and clinical course.

METHODS

Chronological changes in an intramedullary high-intensity area after surgery were retrospectively analyzed in recent 13 patients with spinal dural AVFs who were treated and followed by MRI.

RESULTS

Preoperative intramedullary high-intensity areas were observed on T2-weighted images in all cases. The extent of the high-intensity area correlated with preoperative neurological deficits. The intramedullary high-intensity area was reduced or diminished after successful interruption of AVFs. The high-intensity area started to decrease within 1 to 4 months after treatment in all patients, and disappeared at 2 weeks to 23 months in seven patients. The reduction may suggest interruption of the fistula and improvement of venous circulation, but was not always correlated to clinical improvement. The intramedullary high-intensity areas rapidly disappeared in two patients, but did not clearly correspond to the clinical improvement.

CONCLUSIONS

The time course of postoperative MRI changes is helpful for evaluating the efficacy of treatment after surgery for spinal dural AVFs.

Response of keratinocytes from normal and psoriatic epidermis to interferon-gamma differs in the expression of zinc-alpha(2)-glycoprotein and cathepsin D

Psoriasis is a T cell-mediated inflammatory disease characterized by hyperproliferation and by aberrant differentiation. We found cathepsin D and zinc-alpha(2)-glycoprotein, two catalytic enzymes associated with apoptosis and desquamation, to be present in the stratum corneum of the normal epidermis but absent from the psoriatic plaque. Psoriasis is characterized by an altered response to interferon-gamma (IFN-gamma), including the induction of apoptosis in normal but not in psoriatic keratinocytes, often with opposite effects on gene expression of suprabasal proteins. We found that IFN-gamma binding and signaling were attenuated in psoriasis: The IFN-gamma receptor, the signal transducer and activator of transcription STAT-1, and the interferon regulatory factor IRF-1 were strongly up-regulated by IFN-gamma in normal keratinocytes, but not in psoriatic ones. IFN-gamma strongly up-regulated the expression of the catalytic enzymes cathepsin D and zinc-alpha(2)-glycoprotein in normal keratinocytes but down-regulated them in psoriatic ones; the reverse was true of the apoptotic suppressor bcl-2. We believe that the aberrant response to IFN-gamma plays a central role in the pathophysiology of psoriasis, particularly the disruption of apoptosis and desquamation.

Application of SEM-modified X-ray microscope to entomology and histology, and effects of X-ray coherence in imaging

A projection X-ray microscope has been constructed by modifying a scanning electron microscope (HITACHI S-2500CX). Characteristic internal structures and their changes in an aphid, a fly, an ant, a water bear and a beetle are observed first, non-destructively, by X-ray microscope. Stereo-pair X-ray micrographs of Golgi-stained sections of porcine liver show a network of bile canaliculi and stellate cells. The very clear micrographs presented indicate the usefulness of the microscope in studies of entomology and histology. In some micrographs, very thin whiskers or hairs are visible, which suggests that a phase-contrast effect is present in the imaging. X-ray micrographs of an ant hair taken at various distances between the X-ray source and the specimen, D(s), indicate that the image enhancement due to the phase contrast increases with increasing D(s). Degree of the lateral coherence of X-rays of wave length 0.1 nm is theoretically estimated near the hair, with the result that the coherence increases from about zero (almost complete incoherence) at D(s) = 0.1 mm to about unity (almost complete coherence) at D(s) = 6 mm, in agreement with the observation.

Peripheral quantitative computed tomography of the femoral neck in 60 Japanese women

Peripheral quantitative computed tomography (pQCT) is able to evaluate trabecular and cortical bone separately, and to determine geometric properties from cross-sectional images for noninvasive assessments of mechanical strength. In order to assess the diagnostic value of pQCT of the femoral neck, 60 healthy women were examined with a new pQCT machine, XCT-3000 (Norland-Stratec, Germany), which is suitable for direct measurement of the hip. The region of interest chosen was the center of the femoral neck. pQCT of the distal radius and dual energy X-ray absorptiometry (DXA) of the lumbar spine and femoral neck were also performed. The study demonstrated that total bone mineral density (BMD) (femoral MD) and trabecular BMD (femoral-TBD) decreased with advancing age. Percent cortical area showed a small but significant decrease with advancing age and % trabecular area increased slightly. Both the endosteal perimeter and the periosteal perimeter were relatively constant with aging. Bone strength index (BSI) and stress-strain index (SSI), which reflect the mechanical strength of bone, declined with advancing age, especially after menopause. Femoral TBD correlated strongly with femoral neck BMD by DXA and L2-L4 BMD by DXA but femoral-CBD did not correlate with femoral neck BMD by DXA. Volumetric BMD of the femoral neck and distal radius were closely correlated. It is concluded that (1) cortical thinning occurs with aging by endocortical resorption and loss of femoral-TBD; (2) loss of femoral-CBD occurred at a slower rate than radial CBD, perhaps due to the weight-bearing effect; (3) biomechanical parameters such as the BSI and SSI may reflect increasing fragility of the femoral neck in pre- and postmenopausal women; (4) pQCT of the femoral neck had diagnostic value at least equivalent to that of DXA or pQCT of the distal radius.

Helicobacter pylori infection correlates with severity of reflux esophagitis: with manometry findings

The role of Helicobacter pylori infection in the development and exacerbation of reflux esophagitis was investigated. The prevalence of Helicobacter pylori infection, the severity of atrophic gastritis, and esophageal motility (determined by esophageal manometry by an infusion catheter method) were assessed in patients with mild (n = 46) and severe (n = 27) reflux esophagitis and subjects without reflux (n = 28). Compared with the prevalence of Helicobacter pylori infection in the non-reflux group, the prevalence in the mild and severe reflux groups (60.7%, 47.8%, and 14.8%, respectively) was significantly (P < 0.05) lower. Atrophic gastritis was milder in both reflux groups than in the non-reflux group. The degree of gastritis was also milder in the severe reflux group than in the mild reflux group. The esophageal sphincter pressure was significantly (P < 0.05) lower in the reflux groups than in the non-reflux group, and the amplitude of primary peristalsis was significantly (P < 0.05) lower in the severe reflux group than in the non-reflux group. There were no significant differences between reflux patients with and without Helicobacter pylori infection in the parameters of esophageal manometry. These data imply that a low prevalence of Helicobacter pylori infection may result in a milder grade of atrophic gastritis, and consequently, exacerbate reflux esophagitis.

Treatment of intradural paraclinoidal aneurysms

Intradural paraclinoidal aneurysm still presents conceptual confusion and technical surgical problems. The clinical features of 68 consecutive patients with paraclinoidal aneurysms were analyzed. The pterional approach was used in all patients. Subarachnoid hemorrhage (SAH) occurred in 37 patients from the paraclinoidal aneurysm and in 10 patients from another associated aneurysm. Thirty-four of the 37 ruptured paraclinoidal aneurysms were clipped, two blister-like aneurysms required trapping, and one blister-like aneurysm was coated. Thirteen of the 31 unruptured paraclinoidal aneurysms, consisting of 10 with ruptured associated aneurysm, four symptomatic, and 17 incidental, were clipped and 18 were coated. Favorable outcomes were obtained in 38 of 47 patients with SAH and 17 of 21 patients without SAH. Nine unfavorable outcomes in SAH patients were caused by primary brain damage (5), vasospasm (2), cerebral infarction after trapping (1), and pneumonia (1). All four unfavorable outcomes in non-SAH patients were due to surgical procedures for giant aneurysms or associated basilar artery aneurysm. Removal of the anterior clinoid process was performed to secure the proximal neck in 15 patients with large or giant aneurysms. Multiple clips with or without fenestrated clips were required in all giant aneurysms, and exposure of the cervical internal carotid artery (ICA) in 17 giant or large aneurysms. Fenestrated clips were also useful for one small aneurysm projecting posteriorly. A favorable outcome was achieved in 17 of 19 patients undergoing coating. Coating without clipping might be better for some blister-like ICA aneurysms, even if ruptured. Paraclinoidal aneurysms can be clipped with favorable results using these techniques except for giant aneurysms and associated basilar artery aneurysm.

Postoperative oblique sagittal MR imaging of microvascular decompression for hemifacial spasm

Pre-operative and postoperative oblique sagittal gradient-echo magnetic resonance (MR) imaging was used to evaluate micro-vascular decompression of the facial nerves in 26 patients with hemifacial spasm. The pre-operative MR images were divided into two groups as follows: 22 images in Group I, clear imaging of a high-intensity line and/or spot at the root exit zone (REZ) of the facial nerve; and 4 in Group II, and unreliable image around the REZ. Surgery found that the causative vessel was the vertebral artery (VA) in 9 cases and the anterior inferior cerebellar artery (AICA) or the posterior inferior cerebellar artery (PICA) in 13 cases in Group I, and the AICA or the PICA in the 4 cases in Group II. Postoperative MR imaging showed clear decompression as the high-intensity line and/or spot completely separated from the REZ by a low- and/or iso- intensity area in 9 cases of VA compression repositioned to the petrous dura matter, in 11 cases of PICA or AICA compression treated by shredded Teflon pledgets in Group I and in 3 cases in Group II. Postoperative MR imaging showed an incomplete separation of any high-intensity line and/or spot in the REZ in 2 cases of PICA or AICA compression in Group I and in one in Group II. The outcome was excellent in 22 of 23 cases with clear decompression, and in 1 of 3 cases of unclear decompression. Hemifacial spasm persisted in 3 cases. Oblique sagittal gradient-echo MR imaging is a useful method for postoperative follow-up which can demonstrate changes around the REZ of the facial nerve if hemifacial spasm recurs.

Role of endogenous cathepsin D-like and chymotrypsin-like proteolysis in human epidermal desquamation

Even though the skin surface is acidic (about pH 5), most in vitro studies on desquamation have been performed at alkaline pH. We demonstrate that the standard in vitro model system, which achieves squame shedding upon incubation of plantar stratum corneum for 1 day in an alkaline buffer that must include a chelating agent, can be extended to a more realistic model in which the incubation is for 4 days, at varying pHs from 5 to 8, without exogenous chelators. Desmoglein I from stratum corneum was degraded by the squames shed at pH 5 as well as at pH 8. Squame shedding was inhibited to varying extents by the addition of proteinase inhibitors, whose specificity suggested that the crucial enzymatic activity at pH 8 was a chymotrypsin-like serine proteinase, while a similar activity at pH 5 was accompanied by an aspartic proteinase activity of comparable strength. Four degradation peaks were observed when the insulin B chain was reacted with shed squames at pH 5. Two of these peptides were suppressed by the addition of phenylmethylsulphonyl fluoride, the other two by pepstatin A; chymostatin inhibited all four, but E-64 and leupeptin showed no effect. The implied specificity was confirmed by reacting the insulin (without squames) with the standard enzymes human liver cathepsin D and pancreatic chymotrypsin, reproducing the expected degradation products. These results suggest that epidermal desquamation at acidic pH requires two proteolytic activities, one of which is an analogue of chymotrypsin and the other of cathepsin D. Endogenous proteinases corresponding to these activities have been previously identified, namely the stratum corneum chymotryptic enzyme and the mature active form of cathepsin D.

Technical points to improve surgical results in cases with basilar tip aneurysms

Surgical results in 82 cases with aneurysm (61 ruptured and 21 unruptured) of the bifurcation of the basilar artery were analyzed and the causes of unfavorable outcome and its measures were discussed. Operation was performed in grade I, II, III, or IV of the Hunt and Kosnik's classification for the patients with ruptured aneurysm. Both in ruptured and unruptured cases, patient's age was not considered. As it turned out, 10 elderly (70 years old or older) cases (8 ruptured and 2 unruptured) were included in this study. Unilateral pterional approach was adopted for all but one case, and temporary clip and/or division of the hypoplastic posterior communicating artery was actively used. Surgery was completed with clipping of the aneurysm in all but six cases and overall surgical result consists of 70% of favorable outcomes. The main causes of unfavorable outcome were surgical procedures and primary brain damage due to subarachnoid hemorrhage. And the factors influenced to increase surgical technical damage to the brain were the patient's age, size of the aneurysm, and/or height of the neck from biclinoids line. The outcome of the higher grade (grade III or IV) in elderly cases was miserable, whereas it was not different from anterior circulation aneurysms in younger cases. From the result we concluded that the surgical indication for elderly cases should be limited in cases with lower grade (grade I or II) without large and/or high-positioned aneurysm. To obtain further improvement of the surgical result in younger cases, additional surgical techniques have to be considered to avoid the injury of perforating arteries from P1 and to reduce the pressure of the brain retraction which are the most important hazards for aneurysm surgery in this area.

Oculomotor nerve palsy after surgery for upper basilar artery aneurysms

OBJECTIVE

The goals of this study were to evaluate the relationship between postoperative oculomotor nerve palsy and other clinical factors and to improve preoperative estimations of the risk. Such an evaluation has not been previously described in the literature.

METHODS

Patient records for 77 basilar tip aneurysm cases and 28 basilar superior cerebellar artery aneurysm cases treated between 1981 and 1997 were reviewed. Clinical and radiological parameters were separately analyzed using the chi2 test, and then multiple-regression analysis was used.

RESULTS

Postoperative oculomotor palsy occurred in 25 (32%) patients with basilar tip aneurysms and 11 (39%) patients with basilar superior cerebellar artery aneurysms, in addition to 2 patients with basilar tip aneurysms and 3 patients with basilar superior cerebellar artery aneurysms who exhibited oculomotor palsy before surgery. For both type of aneurysms, the size and direction of the aneurysms were closely related to oculomotor nerve palsy. The complication also tended to occur in early surgery cases, in younger patients, and in patients of poor-clinical grade status.

CONCLUSION

In this study, some clinical and radiological factors were found to be associated with postoperative oculomotor nerve palsy.

Cyclosporin in psoriasis: continuous monotherapy versus intermittent long-term therapy

Using two methods (continuous monotherapy and intermittent therapy) for the treatment of psoriasis with cyclosporine, we observed the clinical efficacy and adverse reactions of each treatment method for more than 36 months to evaluate the clinical usefulness of both methods. Thirty-seven cases were analyzed and the following results were obtained: 1) The PASI score evaluated at each visit was maintained between 5 and 10 by both treatment methods and the improvement rate was more than 70%, while there was no difference in the daily dose between the two treatment methods; 2) The period required to achieve remission tended to be prolonged by intermittent therapy, while no change was observed with continuous monotherapy; 3) The period up to relapse tended to become shorter with both treatment methods but this tendency was more marked with intermittent therapy; 4) E-PAP(evaluation for prognosis with averaged PASI) was lower in the continuous monotherapy group and the patients were more satisfied; 5) The incidence of adverse reactions was similar to that reported in previous studies, with no difference between the two treatment methods in this regard; 6) A significant increase in BUN levels was observed in elderly patients; 7) There were only three cases in which the drug was discontinued due to exacerbation and adverse reactions. Based on the above findings, continuous monotherapy seems to be of greater clinical usefulness than intermittent therapy.