Ultrasonographic evaluation of the caudal vena cava in dogs with right-sided heart disease

INTRODUCTION/OBJECTIVES

In humans with impaired right-sided cardiac function, the caudal vena cava (CVC) diameter serves as a marker of venous congestion. This study aimed to investigate whether ultrasonographic CVC variables could identify the presence of right-sided congestive heart failure (R-CHF) in dogs with right-sided heart disease (RHD).

ANIMALS

Fifty client-owned control dogs and 67 dogs with RHD were enrolled. The dogs with RHD were subdivided into the non-R-CHF (n = 43) and R-CHF (n = 24) groups.

MATERIALS AND METHODS

We measured and compared the ultrasonographic CVC variables and echocardiographic variables among the groups. Receiver operating characteristic (ROC) curve analysis was performed to calculate the sensitivity and specificity of the variables at optimal cutoff values.

RESULTS

We obtained the highest accuracies of the ratio of the shortest diameter (SD) of the minimal CVC area to the aorta diameter (Ao) during inspiration [SD(min)/Ao] and of the ratio of SD(min) to the longest diameter of the minimal CVC area during inspiration [LD(min),SD/LD(min)], with high sensitivities, specificities, and an area under the ROC curve greater than 0.925.

CONCLUSIONS

In addition to the echocardiographic assessment of right-sided cardiac function, the CVC variables in this study, especially SD(min)/Ao and SD/LD(min), would be useful diagnostic indices for identifying R-CHF in dogs with RHD.

Differential regulation of host plant adaptive genes in Pieris butterflies exposed to a range of glucosinolate profiles in their host plants

Specialist herbivores have often evolved highly sophisticated mechanisms to counteract defenses mediated by major plant secondary-metabolites. Plant species of the herbivore host range often display high chemical diversity and it is not well understood how specialist herbivores respond to this chemical diversity. Pieris larvae overcome toxic products from glucosinolate hydrolysis, the major chemical defense of their Brassicaceae hosts, by expressing nitrile-specifier proteins (NSP) in their gut. Furthermore, Pieris butterflies possess so-called major allergen (MA) proteins, which are multi-domain variants of a single domain major allergen (SDMA) protein expressed in the guts of Lepidopteran larvae. Here we show that Pieris larvae fine-tune NSP and MA gene expression depending on the glucosinolate profiles of their Brassicaceae hosts. Although the role of MA is not yet fully understood, the expression levels of NSP and MA in larvae that fed on plants whose glucosinolate composition varied was dramatically changed, whereas levels of SDMA expression remained unchanged. In addition, we found a similar regulation pattern among these genes in larvae feeding on Arabidopsis mutants with different glucosinolate profiles. Our results demonstrate that Pieris larvae appear to use different host plant adaptive genes to overcome a wide range of glucosinolate profiles in their host plants.

Interspecific Differences in the Larval Performance of Pieris Butterflies (Lepidoptera: Pieridae) Are Associated with Differences in the Glucosinolate Profiles of Host Plants

The tremendous diversity of plants and herbivores has arisen from a coevolutionary relationship characterized by plant defense and herbivore counter adaptation. Pierid butterfly species feed on Brassicales plants that produce glucosinolates as a chemical deterrent against herbivory. In turn, the larvae of pierids have nitrile specifier proteins (NSPs) that are expressed in their gut and disarm glucosinolates. Pierid butterflies are known to have diversified in response to glucosinolate diversification in Brassicales. Therefore, each pierid species is expected to have a spectrum of host plants characterized by specific glucosinolate profiles. In this study, we tested whether the larval performance of different Pieris species, a genus in Pieridae (Lepidoptera: Pieridae), was associated with plant defense traits of putative host plants. We conducted feeding assays using larvae of three Pieris species and 10 species of the Brassicaceae family possessing different leaf physical traits and glucosinolate profile measurements. The larvae of Pieris rapae responded differently in the feeding assays compared with the other two Pieris species. This difference was associated with differences in glucosinolate profiles but not with variations in physical traits of the host plants. This result suggests that individual Pieris species are adapted to a subset of glucosinolate profiles within the Brassicaceae. Our results support the idea that the host ranges of Pieris species depend on larval responses to glucosinolate diversification in the host species, supporting the hypothesis of coevolution between butterflies and host plants mediated by the chemical arms race.

Bioengineered osteochondral precursor for treatment of osteochondritis dissecans in a Thoroughbred filly

CASE REPORT

A 13-month-old Thoroughbred filly was diagnosed with osteochondritis dissecans (OCD) of the medial tibial malleolus. A sponge impregnated with platelet-rich plasma, bone morphogenetic protein-2, mesenchymal stem cells and gelatin β-tricalcium phosphate was applied to the OCD site following arthroscopy and debridement. Postoperative radiography (every week for 16 weeks), computed tomography (CT) (16 weeks postoperatively), arthroscopy (16 weeks postoperatively) and biopsy of the regenerated tissue (16 weeks postoperatively) were performed to evaluate the outcome. Radiographically, the defect began to diminish 3 weeks postoperatively and had disappeared by 12 weeks. CT images showed that the debrided site was filled with ossified tissue and arthroscopy showed that the regenerated tissue was covered with smooth tissue, which a biopsy showed was fibrocartilage.

CONCLUSIONS

Placing the impregnated sponge in the OCD lesion facilitated satisfactory regeneration of tissue in the debrided area, but the regenerated cartilage was fibrocartilage. This method may be a viable option for the treatment of cases of equine OCD, but further work to determine how to induce hyaline cartilage regeneration is required.

Long-term results of tension-band laminoplasty for cervical stenotic myelopathy

We reviewed 75 patients (57 men and 18 women), who had undergone tension-band laminoplasty for cervical spondylotic myelopathy (42 patients) or compression myelopathy due to ossification of the posterior longitudinal ligament (33 patients) and had been followed for more than ten years. Clinical and functional results were estimated using the Japanese Orthopaedic Association score. The rate of recovery and the level of postoperative axial neck pain were also recorded. The pre- and post-operative alignment of the cervical spine (Ishihara curve index indicating lordosis of the cervical spine) and the range of movement (ROM) of the cervical spine were also measured.

The mean rate of recovery of the Japanese Orthopaedic Association score at final follow-up was 52.1% (sd 24.6) and significant axial pain was reported by 19 patients (25.3%). Axial pain was reported more frequently in patients with ossification of the posterior longitudinal ligament than in those with cervical spondylotic myelopathy (p = 0.027). A kyphotic deformity was not seen post-operatively in any patient. The mean ROM decreased post-operatively from 32.8° (sd 12.3) to 16.2° (sd 12.3) (p < 0.001). The mean ROM ratio was 46.9% (sd 28.1) for all the patients. The mean ROM ratio was lower in patients with ossification of the posterior longitudinal ligament than in those with cervical spondylotic myelopathy (p < 0.001). Compared to those with cervical spondylotic myelopathy, patients with ossification of the posterior longitudinal ligament had less ROM and more post-operative axial neck pain.

Focal brain edema and natriuretic peptides in patients with subarachnoid hemorrhage

Central salt wasting syndrome may be caused by pathological increases in serum natriuretic peptides after subarachnoid hemorrhage (SAH). However, it is unclear as to why the serum concentration of atrial natriuretic peptide (ANP) or brain natriuretic peptide (BNP) increases in the subacute phase of SAH. The present study was designed to assess the correlation between focal brain edema and serum concentration of ANP or BNP in patients with SAH. Focal brain edema was found in 8 SAH-patients and peaked between days 4 and 7 of SAH. The mean serum ANP and BNP levels in patients with focal brain edema were significantly higher than those in patients without focal brain edema between days 4 and 14 of SAH. These results suggest that focal brain edema might correlate with increased levels of ANP and BNP in the subacute phase of SAH.

Vascular endothelial growth factor expression in pituitary adenomas

Vascular endothelial growth factor (VEGF) is known to be a mediator of angiogenesis and vascular permeability. A cystic component and hemorrhage are often found in pituitary adenomas. In the present study we assess the VEGF expression based on immunohistochemical examinations in 48 pituitary adenomas. All the adenomas showed some VEGF immunoreactivity mainly in the cytoplasm of tumor cells. Of the 48 adenoma-cases, 16 cases had a strong VEGF immunoreactivity, 26 cases had a moderate one, and 6 cases had a weak one. On the MR images, a cystic component was found in 16 cases (33.3%), and a hemorrhage was found in 18 cases (37.5%). The VEGF immunoreactivity had a significant relationship with the cystic component but neither the hemorrhage, size, recurrence, or HE classification. These findings suggest that VEGF might play a potential role in the pathogenesis of cystic formation in pituitary adenomas.

A role of glial fibrillary acidic protein in hippocampal degeneration after cerebral trauma or kainate-induced seizure

Astrocytes perform a variety of functions in the adult central nervous system (CNS). Recent evidence suggests the robust upregulation of glial fibrillary acidic protein (GFAP) after CNS insult. However, little is known about the role of GFAP in the hippocampal degeneration after brain injury. We herein compared the GFAP knockout (KO) and wild type (WT) mice on the histological and behavioral outcome in response to cerebral trauma or kainic acid (KA)-induced seizure. Although all KO mice showed hippocampal CA3 neuronal degeneration. WT mice did not show any neuronal degeneration in CA3 subfield at 72 hrs after trauma. Thereafter, KO mice showed a higher susceptibility to KA-induced seizures and an increased number of pyknotic CA3 neurons 72 hrs after KA administration. These results indicate that GFAP plays a crucial role in the hippocampal neurodegeneration after CNS insult.

Mitogen-activated protein kinases phosphorylation in posttraumatic selective vulnerability in rats

Mitogenic stimulation of the Mitogen-activated protein kinase (MAPK) pathway modulates the activity of many transcriptional factors leading to biological responses. Of these, three MAPK cascades are well characterized as extracellular signal-regulated protein kinase (ERK), c-Jun NH(2)-terminal kinase (JNK), and p38 pathways. The aim of this study was to investigate the topographic distribution and the role of activated MAPK pathways after fluid percussion injury (FPI) in rats. In the present results, FPI significantly induced ERK- and JNK-phosphorylation, but not p38-phosphorylation in the cortex and hippocampus at the injury site. The immunoreactivity for phospho-ERK was localized in the superficial neuronal layers, dentate hilar neurons, and the damaged CA3 neurons after 30 mins of FPI. Double immunostaining showed that phospho-ERK was prominent in astrocytes 6 hrs after TBI. The current results suggest that MAPK pathways are involved in signal transduction after FPI.

Female gender as a risk factor for hypokalemia and QT prolongation after subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) often causes hypokalemia and QT prolongation. The sex disparities among 73 patients with SAH and 96 control subjects were examined. On the first day of SAH, the mean serum potassium level was significantly lower and the mean corrected QT interval was significantly longer in the female SAH group compared with either the female control or male SAH group. These findings suggest female susceptibility to hypokalemia and QT prolongation after SAH.

Lymphoepithelioma-like carcinoma of rectum: possible relation with EBV

Lymphoepithelioma-like carcinoma (LEC) of the colon is very rare. Here we report a case of LEC originating in the rectum that was closely associated with Epstein-Barr virus (EBV) infection. The histologic and immunohistologic features, namely, poorly differentiated adenocarcinoma with lymphoid stroma, showed this tumor to be an LEC. The EBV genome was detected by PCR using DNA obtained from tumor tissue sections. Immunohistochemically, EBV-determined nuclear antigen 2 was detected in the tumor cells, and in situ hybridization using EBV-encoded small RNAs probe showed positive labeling in some tumor cells together with a few stromal lymphoid cells. There are some reports of LEC cases that originated in the colon; however, a relation with EBV was not demonstrated. We report here a case of LEC of the rectum demonstrating a possible relation with EBV.

Cisternal MHPG level inversely correlates with Glasgow coma scale after aneurysmal subarachnoid hemorrhage

We measured the concentrations of monoamines and amino acids in the cisternal cerebrospinal fluid obtained from 15 patients after aneurysmal subarachnoid hemorrhage. Based on the Glasgow Coma Scale (GCS), the patients were divided into two conscious (GCS always 14 or better from the third post-operative day to Day 12; n = 8) and unconscious groups (n = 7). We examined the concentrations of monoamines and amino acids between the two groups and evaluated the correlation between the concentrations and the GCS at CSF sampling. The concentration of MHPG was significantly higher in the unconscious than in the conscious group from Days 4 to 12. A significant inverse correlation was observed between the MHPG concentration and the GCS (r = approximately 0.635, p < 0.0001). Measuring the cisternal MHPG concentration may be useful for estimating convalescence after subarachnoid hemorrhage.

Neuroserpin, a neuroprotective factor in focal ischemic stroke

Because recent studies have indicated that tissue plasminogen activator (tPA) aggravates neurodegenerative processes in many neural pathologies, we studied whether the endogenous tPA antagonist neuroserpin has a neuroprotective effect in an animal model of focal ischemic stroke. After induction of a focal ischemic stroke in the mouse by occlusion of the middle cerebral artery, we found that microglial cells accumulated in the marginal zone of the infarct are the most important source for both plasminogen activators, tPA and uPA. To investigate the effect of neuroserpin on the size and the histology of the infarct we produced transgenic mice overexpressing neuroserpin approximately sixfold in the nervous system. In the brain of these mice the total tPA activity in the uninjured tissue was strongly reduced. After induction of a focal ischemic stroke in the transgenic mice by a permanent occlusion of the middle cerebral artery (MCA), the infarcts were 30% smaller than in the wild-type mice. Immunohistochemical analyses and in situ hybridization revealed an attenuation of the microglial activation in the reactive zone. Concomitantly, the microglial production of tPA and uPA, as well as the PA-activity in the infarct region was markedly reduced. Thus, our results indicate that neuroserpin reduces microglial activation and, therefore, the PA activity and has a neuroprotective role after focal ischemic stroke.

Peduncular hallucinosis due to a pineal meningioma. Case report

The authors report the case of a 53-year-old woman who experienced visual hallucinations diagnosed as peduncular hallucinosis (PH). The cause of the PH was compression of the quadrigeminal plate and/or the splenium due to a meningioma originating from the falcotentorial junction (pineal meningioma). The nature of the visual hallucinations was depicted in drawings created by the patient herself. This is the first report of PH caused by a tumor located in the pineal region.

Real time monitoring of glutamate following fluid percussion brain injury with hypoxia in the rat

In this study, extracellular glutamate (Glu) was monitored in real time using a biosensor following traumatic brain injury (TBI) either with or without inducing hypoxia in the rat Fluid-percussion model. We also measured the cortical contusion volume at 3 days after the insult. The animals were divided into 3 groups. Group 1 was subjected to TBI only, Group 2 to TBI followed by 20 min of moderate hypoxia (FiO2: 10%) and Group 3 to 20 min of moderate hypoxia without TBI. The surge increase in the extracellular Glu concentration occurred immediately after TBI in Groups 1 and 2. Group 2 showed a prolonged efflux of Glu during hypoxia. Group 3 Glu showed low continuous steady levels. The contusion volume in Group 2 was significantly larger than in Group 1. To test the possible involvement of apoptosis in Groups 1 and 2, rats were sacrificed at 1, 6, 24 and 72 h after TBI. Immunohistochemical studies showed an increased number of both CPP32 positive cells at 24 h and TUNEL cells at 72 h in Group 2. These results suggest that TBI with moderate hypoxia induced a prolonged efflux of Glu that resulted more cortical damage due to necrosis and apoptosis.

Mn-SOD and Bcl-2 expression after repeated hyperbaric oxygenation

To clarify the mechanism of ischemic tolerance induced by HBO, we investigated the effect of HBO on immunoreactivity to Bcl-2 and Bax, apoptosis-regulating protein, or Mn-SOD, a radical scavenging system, in the CA1 sector of the gerbil hippocampus. Pretreatment comprising, five sessions at 2 ATA (atmosphere absolute) every other day, but not that comprising, ten sessions at 3 ATA every day, caused significant increases in Bcl-2 and Mn-SOD immunoreactivity in the CA1 sector compared with in the sham pretreatment group. No significant differences in Bax immunoreactivity and neuronal density in the CA1 hippocampal neurons was observed between the groups. These results suggest that protection against mitochondrial alterations after ischemia through Mn-SOD and/or Bcl-2 expression is related to the ischemic tolerance induced by repeated HBO pre-treatment.

Hepatocyte growth factor reduces infarct volume after transient focal cerebral ischemia in rats

Hepatocyte growth factor (HGF) was originally discovered as a powerful mitogen for hepatocytes. HGF functions both as a neurotrophic factor as well as an angiogenetic factor. Furthermore, HGF has an anti-apoptotic effect on vascular endothelial cells. The present study examined the neuroprotective effect of HGF after transient focal cerebral ischemia in rats, in which an anti-apoptotic and an angiogenetic effect of HGF was assumed to contribute to the reduction of the infarct volume. The intraventricular administration of human recombinant HGF (90 micrograms) significantly reduced the infarct volume after 120 minutes occlusion of both the right middle cerebral artery (MCA) and the bilateral common carotid arteries (CCAs). In a separate series of experiments, we investigated both the anti-apoptotic effect on neurons and the angiogenetic effect of HGF histopathologically. The number of survival neurons and vascular lumina in the HGF group were significantly higher than those in the vehicle group. A large number of TUNEL positive neurons were observed in the inner boundary of the infarct area in the vehicle group, whereas only a few TUNEL positive neurons were observed in a corresponding area in the HGF group. In the HGF group, Bcl-2 protein was obviously represented in survival neurons as well as in vascular endothelial cells and in glial cells subjected to ischemia. These data suggest that HGF prevents apoptotic neuronal cell death by upregulating the production of Bcl-2 protein and by an angiogenetic effect in the central nervous system which affected transient focal cerebral ischemia.

Staged spinal cord decompression through posterior approach for thoracic myelopathy caused by ossification of posterior longitudinal ligament

STUDY DESIGN

Prospective clinical study of the effect of staged elimination of anatomic factors inhibiting posterior shift of the thoracic spinal cord on the degree of posterior shift of the thoracic spinal cord and its significance in augmenting the safety of ossification of posterior longitudinal ligament (OPLL) manipulation in thoracic OPLL myelopathy.

OBJECTIVES

To develop a comprehensive method that enables safe and sufficient decompression of the spinal cord for thoracic OPLL myelopathy.

SUMMARY OF BACKGROUND DATA

Decompression of the spinal cord by direct manipulations of thoracic OPLLs, via either anterior or posterior approach, caused some iatrogenic catastrophic spinal cord injuries, and methods to prevent such injuries during surgery have not yet been developed.

METHODS

Procedures of elimination of anatomic factors inhibiting posterior shift of the thoracic spinal cord were performed in stages at intervals of between 1 month and 11 years depending on patients' neurologic status. The first stage operation consisted of extensive cervicothoracic laminoplastic decompression with or without posterior longitudinal durotomy, and if the decompression were insufficient, measures for OPLL-spinal cord separation with or without OPLL manipulation were added.

RESULTS

All 17 patients with thoracic OPLL myelopathy showed improvements of neurology comparable with those with successful anterior approaches after decompression. The mean follow-up period was 42 months (range 6-101 months). Neurologic improvements persisted for the entire follow-up period in all patients except one patient who developed arachnoid cyst compressing the dorsum of the once-decompressed spinal cord 30 months after surgery.

CONCLUSIONS

Staged posterior decompression to eliminate anatomic factors inhibiting posterior shift of the thoracic spinal cord is the safest and the most reliable method of spinal cord decompression to treat thoracic OPLL myelopathy, so far. However, long-term results are required before the methods can be established.

Preferential conditions for and possible mechanisms of induction of ischemic tolerance by repeated hyperbaric oxygenation in gerbil hippocampus

OBJECTIVE

We reported previously that repeated hyperbaric oxygenation (HBO) as pretreatment induced ischemic tolerance in the gerbil hippocampus. This study was conducted to determine the preferential conditions for induction of ischemic tolerance by HBO and the mechanism of this induction through immunohistochemical analysis of Bcl-2, Bax, and manganese superoxide dismutase expression.

METHODS

Five-minute forebrain ischemia was produced in gerbils after pretreatment with 2 atmospheres absolute (ATA) HBO once every other day for one, three, or five sessions, 2 ATA hyperbaric air once every other day for five sessions, or 3 ATA HBO once daily for 10 sessions. Histological examinations were then performed. Two days after pretreatment with 2 ATA HBO once every other day for five sessions or with 3 ATA HBO once daily for 10 sessions, sections were analyzed immunohistochemically.

RESULTS

Pretreatment with 2 ATA HBO once every other day for three or five sessions induced ischemic tolerance; however, pretreatment with 2 ATA HBO for one session, 2 ATA hyperbaric air once every other day for five sessions, or 3 ATA HBO once daily for 10 sessions did not. Pretreatment with 2 ATA HBO once every other day for five sessions, but not with 3 ATA HBO once daily for 10 sessions, significantly increased Bcl-2 and manganese superoxide dismutase immunoreactivity in the CA1 sector.

CONCLUSION

These results suggest that protection against mitochondrial alterations after ischemia through manganese superoxide dismutase and/or Bcl-2 expression may be related to induction of ischemic tolerance by repeated HBO pretreatment.

Evaluation of spontaneous intracranial hypotension: assessment on ICP monitoring and radiological imaging

We describe two recent cases of spontaneous intracranial hypotension. A 38-year-old woman developed a severe postural headache. Magnetic resonance imaging (MRI) showed marked dural enhancement. Histopathological findings of dural biopsy showed numerous dilated vessels in the dura, rather than hypertrophic change. Lumber CSF pressure was 5 cmH2O and RI cisternography suggested CSF leakage. A 58-year-old woman with postural headache and vertigo had bilateral subdural haematoma associated with diffuse dural enhancement on MRI. Lumber CSF monitoring confirmed persistent low pressure ranging from 0-5 cm H2O. MRI myelography revealed multiple CSF pouches along the whole spinal axis. CSF leakage was demonstrated on Radioisotope (RI) cisternography. Both cases described in this report were diagnosed as spontaneous intracranial hypotension caused by CSF leakage from spinal meningeal diverticula and were successfully treated by intravenous Factor XIII administration.

Hepatocyte growth factor reduces the infarct volume after transient focal cerebral ischemia in rats

Hepatocyte growth factor (HGF) was originally discovered as a powerful mitogen for hepatocytes. HGF also has been reported to function as a neurotrophic factor as well as an angiogenetic factor. The present study examined the neuroprotective effect of HGF against transient focal cerebral ischemia in rats, in which an anti-apoptotic and an angiogenetic effect of HGF was assumed to contribute to the reduction of the infarct volume. The intraventricular administration of human recombinant HGF prevented neuronal death after 120 min of occlusion in the right middle cerebral artery and the bilateral common carotid arteries. HGF significantly reduced the infarct volume in a dose-dependent manner. In a separate series of experiments, we next histopathologically investigated both the anti-apoptotic effect on neurons and the angiogenetic effect of HGF. A large number of TUNEL positive neurons were observed in the inner boundary of the infarct area in both the control and the vehicle group whereas only a few TUNEL positive neurons were observed in the corresponding area in the HGF group. In the HGF group, Bcl-2 protein was obviously represented in surviving neurons subjected to ischemia. The number of the vascular lamina in HGF group were significantly higher than those in the vehicle group. These data suggest that HGF appears to have an ability to prevent apoptotic neuronal cell death while also possessing an angiogenetic effect in the central nervous system which was affected with transient focal cerebral ischemia.

[Influence of intubation maneuver with or without premedication for intracranial hemorrhage with unconsciousness]

PURPOSE

To clarify the influence of intubation maneuver with or without premedication for intracranial hemorrhage with unconsciousness.

METHODS

Between May 1995 and May 2000, we analyzed retrospectively 46 patients who had received intubation for unconsciousness and were found non-traumatic intracranial hemorrhage by head computer tomography at the Trauma and Critical Care Center, National Defense Medical College. They were divided into two groups, Drug group in which drugs were used before intubation and Control group which were intubated without drugs. Physical findings on admission, head CT findings, Glasgow Outcome Score(GOS) at discharge were analyzed between the groups.

RESULTS

There were no significant differences for background of subjects between the groups. In the Drug group, diazepam, pentazocine, lidocaine, nifedipine and nicardipine were used before intubation. GOS in the Control group was significantly greater than in the Drug group(p < 0.01).

CONCLUSION

In case of intubation for unconscious patients who may suffer intracranial hemorrhage, using premedication leads to favorable outcome.

[Tiny aneurysms of cortical arteries presenting as an acute subdural hematoma: a case report]

A case of an acute subdural hematoma due to the rupture of a tiny aneurysm of a cortical artery is described. A 68-year-old man lightly hit the right side of his head. About 1 hour later, he became drowsy and exhibited moderate hemiparesis on the left side on admission. Computed tomographic scanning demonstrated an acute subdural hematoma on the right temporoparietal region. In the past, he had undergone the clipping of a non-ruptured aneurysm and a subdural-peritoneal shunt operation on the same side in another hospital. On surgical evacuation of the subdural hematoma, a pulsating bleeding from a ruptured tiny aneurysm of a cortical artery was observed. There were also some similar tiny aneurysms on other cortical arteries. A photograph of such a tiny aneurysm was first taken and presented.

Cystic schwannoma of the orbit: case report

BACKGROUND

Cystic lesions of the orbit have diverse clinical findings and histopathological features. We report an orbital schwannoma composed of a single cyst.

CASE DESCRIPTION

A 62-year-old woman with an intraconal cystic tumor in the left orbital cavity is described. The cystic tumor was totally removed and the pathological diagnosis of the cyst wall was schwannoma composed of both Antoni type A and B.

CONCLUSIONS

A rare case of cystic schwannoma of the orbit is reported. This case may contribute to an improved preoperative differential diagnosis for cystic lesions of the orbit.

[Thallium-201 single photon emission tomography of intracranial angiomas]

We herein describe thallium-201 single photon emission tomography (T1-201 SPECT) findings in three cases with intracranial angioma. One of the lesions which was associated with chronic encapsulated intracerebral hematoma showed moderate accumulation of T1-201, but, others demonstrated no accumulation. The usefulness and limitations of T1-201 SPECT in differential diagnosis of intracranial mass lesions are discussed.

Solitary fibrous tumor of the meninges in the posterior cranial fossa: magnetic resonance imaging and histological correlation--case report

A 58-year-old female presented with a rare case of intracranial solitary fibrous tumor (SFT) manifesting as progressive ataxic gait and hearing loss on the left persisting for 6 months with recent symptoms of increased intracranial pressure. Computed tomography demonstrated a large isodense irregular-shaped mass in the left posterior cranial fossa. T2-weighted magnetic resonance imaging showed two components appearing as very low intensity and high intensity. Extreme-lateral suboccipital craniotomy was performed. Gross total resection was achieved except for some dural attachment in the jugular foramen. All symptoms and signs subsided after surgery. Histological, immunohistochemical, and electron microscopic examinations led to a diagnosis of SFT. The strongly hypointense areas on the T2-weighted images were hypocellular region characterized by disorganized spindle cells and thick bands of collagen. The hyperintense areas on the T2-weighted images were hypercellular region mimicking hemangiopericytoma. Strong immunoreactivity for CD34 was also helpful in the diagnosis. Electron microscopy revealed absence of pinocytic vesicles and dense laminae which are characteristic of hemangiopericytoma. The magnetic resonance imaging appearance of SFT seems to be pathognomonic.

The value of a new method for assessing the separate functions of the long tracts and involved segments in patients with cervical myelopathy

In order to assess accurately lesions of the spinal cord in patients with cervical myelopathy we have developed a new method of examination, which is based on the Japanese Orthopaedic Association (JOA) scoring system. The method attempts to assess separately the functions of the long tract and any involved cord segments in respect to the period after treatment. It was used in 117 consecutive patients who were divided into 2 groups based on whether or not there was a T2-high-intensity lesion within the spinal cord, as revealed by a preoperative magnetic resonance imaging scan (MRI). The results of this method correlated well with the MRI findings. It was assumed that the degree of function of the upper limbs in patients with a T2-high-intensity lesion revealed more about a segment than about the long tract.

Elevation of metallothionein level in preneoplastic lesions during chemical hepatocarcinogenesis of the Fischer 344 rat

Metallothionein (MT) is inducible by various stimuli such as metals and physiological stress. Although elevated MT expression in certain type of tumors has been reported, there are few data available on the roles of MT in tumor formation. In this study, we immunohistochemically examined MT expression in gluthathione S-transferase placental type p (GST-P)-positive preneoplastic liver lesions induced by a chemical carcinogen and further examined the relationship between MT expression and the proliferative activity of the preneoplastic cells, using bromodeoxyuridine (BrdU) labeling indices. Eleven male Fischer rats (F344/DuCrj, 9 weeks old) were subjected to the Solt-Farber protocol. Thereafter, the livers were removed, frozen and sectioned serially for immunohistochemical staining of MT and GST-P. Eight rats were given six injections of BrdU before sacrifice. In 92.8% of GST-P positive lesions, high MT staining intensity was demonstrated. On the other hand, there was no correlation between the intensity of MT staining and the BrdU labeling indices of the preneoplastic lesions. Our results indicate that MT is a useful positive marker for preneoplastic liver lesions, though the reason why MT is expressed in the preneoplastic and neoplastic lesions remains to be elucidated.

The effect of muscle-tone-reducing procedures in athetotic head movements: partial nerve block by lidocaine and surgical release of the neck muscles

OBJECTIVE

To investigate the effect of muscle-tone-reducing procedures (MTRPs), i.e. partial nerve block by lidocaine (PNB) and surgical release of muscle attachment to bone (SRMAB), on incessant involuntary head movements in athetotic patients.

METHODS

Pre/post-MTRP changes in neck-muscle activities, glabella movement and maximum isometric forces of the head were measured in six athetotic patients with severe spondylotic myelopathy resulting from incessant involuntary head movements.

RESULTS

Pre/post-MTRP changes in neck-muscle activities resembled those after gamma-block. In four patients, PNB reduced the maximum isometric force by no more than 40% of pre-PNB force, while decreasing the amount of involuntary head movements to 37-65% of the pre-PNB value in the frontal plane. MRSAB reduced the force by less than 40% of pre-SRMAB force in 4 MRSAB tested patients, while decreasing the amount of involuntary head movements to 12-45% of the pre-SRMAB value in all 6 patients.

CONCLUSION

MTRPs reduced involuntary head movements significantly while preserving voluntary muscle forces relatively well. PNB and SRMAB procedures have in common the effect of reducing gain in the myotatic reflex pathway by decreasing the excitatory inflows to alpha-motoneurons via muscle spindle Ia-afferents, which resulted from blocking mainly gamma-efferent conduction by PNB, and reducing background tension in muscle spindles by SRMAB.

New method of assessing outcome of treatment for cervical myelopathy (M/T method)--preliminary report

In some patients with cervical radiculomyelopathy, neurological examination reveals extreme muscle weakness in an upper extremity with no, or a relatively insignificant, sensory deficit. In assessment of treatment outcome in these patients, the previous method used is thought to be unsuitable. We developed a new method of assessment (the M/T method) in which the recovery of upper extremity muscle weakness is assessed. The purpose of this study was to evaluate this new method. In the M/T method, change in the function of the spinal cord, including the anterior root, is expressed as an index number (recovery rate) in relation to the time-course. The function of the nerve tissue is expressed as the value for the manual muscle testing (MMT) of muscle power, and the muscle tested is represented by one that has the least MMT value before treatment. The unit of measurement of the time-course is 3 months. The index is the difference between the MMT value at the time of follow-up and that before treatment, divided by the number of time units after treatment. The index can be expressed in both fractional and decimal forms. Fractions are useful for examining an individual patient's progress and the decimal form is useful for comparing the data of multiple patients. The M/T method was employed in 16 patients (13 men, 3 women; age, 45-79 years; follow-up, 6 months - 8 years) whose chief complaints were muscle weakness in the upper extremities and who had undergone double-door laminoplasty. Seven patients had an M/T index of 1 or more; the score was 4 in one patient, 2 in four patients, and 1 in two patients. Two patients had an M/T index between 0 and 1; 0.17 and 0.25. Five patients had an index value of 0. The M/T index in two patients was less than 0; -0. 17 and -0.11. Using the M/T method, recovery can be presented as an index number, and as a result, it is easy to compare differences in the recovery rate among patients. The M/T method is useful for evaluation of the viability of the spinal cord, including the anterior root; in particular for those patients in whom neurological examination reveals extreme muscle weakness in an upper extremity with no, or a relatively insignificant, sensory deficit.

Large empty sella with an intrasellar herniation of an elongated third ventricle. Case report

A 73-year-old female presented with a large empty sella with herniation of an elongated third ventricle concomitant with herniation of the surrounding subarachnoid space into the sella, manifesting as visual impairment and amenorrhea without galactorrhea. Magnetic resonance imaging and computed tomography cisternography clearly showed the large empty sella, without evidence of either hydrocephalus or benign intracranial hypertension, which is extremely rare.

A clinical study on the effects of pulsed Nd:YAG laser irradiation at root canals immediately after pulpectomy and shaping

OBJECTIVE

The effects of pulsed Nd:YAG laser irradiation for the treatment of root canals immediately after pulpectomy and shaping with regard to improvement of symptoms were evaluated clinically.

SUMMARY BACKGROUND DATA

The effects of pulsed Nd:YAG laser irradiation for the treatment of root canals were experimentally investigated using an animal model, but not under clinical conditions.

MATERIALS AND METHODS

Thirty-eight teeth from 29 patients were diagnosed as normal or irreversible pulpitis were used. After extirpation of pulp and shaping using a step-back technique and cleansing with 5% sodium hypochlorite (NaOCl) and 3% hydrogen peroxide (H2O2), laser irradiation was applied at 1 W and 15 pps for 1 second in 23 teeth (laser-treated group). Root canals were then obturated with gutta-percha points and sealer by the lateral condensation method. The condition of the obturations was confirmed radiographically. The control teeth were treated in the same way, but without laser irradiation. Occurrence of spontaneous pain was recorded 1 day after treatment and occurrence of percussion pain was recorded 1, 2, and 3 weeks after treatment.

RESULTS

Effective ratio, which was the ratio of the number of "none" teeth to total teeth number in the laser-treated group, was higher than that in the control group, but there was no significant difference between 2 groups with regard to spontaneous and percussion pain (p > 0.05).

CONCLUSION

These results suggest that the clinical application of pulsed Nd:YAG laser might be advantageous for the one-visit treatment of root canals immediately after pulpectomy shaping and to reduce postoperative pain.

[The distribution of nerve endings in the human cervical nerve roots]

OBJECTIVE

To find out the distribution of nerve endings in the dural sheath of cervical nerve roots and to study the mechanism of cervical radicular pain.

METHOD

2069 20 microm serial sections were made from 39 cervical root-dorsal root ganglion specimens obtained from 18 postmortems. By using optical microscope and Suzuki silver impregnation method and Klüver-Brrera method, we examined the morphology, quantity and distribution of the nerve ending in the nerve sheath of the root, dorsal root ganglion (DRG) and the spinal nerve of these sections.

RESULT

There were several kinds of nerve endings such as free nerve endings in the nerve sheath of the root, the dorsal root ganglion, and the spinal nerve. Free nerve endings were distributed in the proximal and distal portions of DRG sheath more extensive than that in other parts of the dural root-sheaths.

CONCLUSION

The free nerve endings in the dural root-sheaths especially those in the DRG sheath are thought to play an important role in cervical radicular pain.

Chronic liver injury promotes hepatocarcinogenesis of the LEC rat

The Long-Evans rat with a cinnamon-like color (LEC) is a mutant rat that spontaneously suffers from chronic liver injury and subsequent hepatocellular carcinoma (HCC) caused by abnormal copper accumulation in the liver. We attempted to elucidate the role of prolonged liver cell injury on LEC rat hepatocarcinogenesis using a copper-deficient diet (CuDD) to inhibit the occurrence of consequent liver injury. The animals were fed the CuDD from the age of 4 weeks until being killed at the age of 10 months. Diethylnitrosamine (DEN) was administered at the age of 8 weeks. Groups fed a basal diet (BD) with or without the administration of DEN were also assigned as control groups. The animals fed the BD manifested liver injury, while those fed the CuDD did not show liver dysfunction until death. The number and volume of glutathione S-transferase placental form (GST-P)-positive preneoplastic lesions in the liver, which were calculated from the data on two-dimensional planes, were examined to clarify the promotive effect of chronic liver injury on the development of HCC. Regarding the size of the lesions, which indicated the intensity of the promotive effect, the lesions in the livers of rats fed the BD with DEN were much larger than those of rats fed the CuDD with DEN. Feeding the LEC rats with CuDD completely suppressed the manifestation of liver injury, and it was clearly shown that prolonged liver injury had a promotive effect on the LEC rat hepatocarcinogenic process.

Secretory meningioma with severe perifocal edema--case report

An 82-year-old male presented with a small parasagittal meningioma associated with disproportionately severe perifocal edema. Histological examination including immunohistochemical staining and electron microscopy resulted in a diagnosis of secretory meningioma. In addition to tumor size, the edema could not be explained by location, growth rate, vascular involvement, or other factors. We conclude that secretory meningiomas may possess an innate ability to cause brain edema.

Expression of p21(waf-1/cip-1) is significantly induced in the livers of LEC rats with chronic liver injury

It is reported that hepatocytes isolated from LEC rats with chronic liver injury show reduced growth activity in primary culture. To elucidate the molecular basis of this phenomenon, we examined expression of p21(waf-1/ciP-1) and p27, cyclin-dependent kinase inhibitors, by northern blot analysis. The expression of p21(waf-1/cip-1 ) in the LEC rat liver was 3-fold higher than that of age-matched SD rat liver, while there was no significant difference in p27 expression level. Western blot analysis also revealed a significant increase in p21(waf-1/cip-1) in the nuclear matrix fraction of the LEC rat liver. Immunohistochemically, p21(waf-1/cip-1) was detected in the nuclei of normal LEC rat hepatocytes, but not in those of hepatocellular carcinoma cells, suggesting selective growth of neoplastic hepatocytes.

Tension-band laminoplasty of the cervical spine

A new laminoplasty of the cervical spine has been developed using preserved ligaments as a tension-band. The laminae were enlarged in an open-door fashion and spacers inserted to maintain the spinolaminoligamentous complex intact. The stretched ligaments exerted a tension-band effect on the spacers and stabilised them so that neck movements could be started as soon as bleeding stopped. The spacers were iliac grafts, or were made of a bioactive ceramic which proved more satisfactory. The results of 102 cases with ceramic spacers showed an average preservation of preoperative movement between C2 and C7 to be 79% in cervical spondylotic myelopathy and 67% in ossification of the posterior longitudinal ligament at 3 years after operation. No spacer became displaced. CT showed new bone formation in the lamina-ceramic gap in 59% of the spacers used in cervical spondylotic myelopathy by sixth months and in 63% in cases of ossification of the posterior longitudinal ligament by the third month. Neurological recovery was comparable to that after other types of laminoplasty, but the new method allows better function of the neck and more new bone formation around the spacers.

Extradural tethering effect as one mechanism of radiculopathy complicating posterior decompression of the cervical spinal cord

STUDY DESIGN

This study used anatomical and clinical data to analyze the postoperative tension-status of cervical roots after posterior decompression of the cervical spinal cord. The efficacy of longitudinal durotomy with regard to prevention of postoperative palsy was investigated in a controlled study.

OBJECTIVES

To elucidate the mechanism of postoperative radiculopathy and to prevent its occurrence.

SUMMARY OF BACKGROUND DATA

Previous anatomical studies by the authors revealed that the posteromedial shift of the dura-root junction following posterior bulging of the cervical dural sac exerted a traction force on the portion of the roots outside the dural sac and reduced the tension on the rootlets inside the dural sac. These traction-related phenomena disappear after longitudinal durotomy.

METHODS

Lengths of various parts of an anterior root were measured in 20 Japanese adult cadavers. The shortest pre- and postoperative distances between the anterolateral mid-edge of the spinal cord and dura-root junction were compared, using computed tomography-myelograms of postoperative C5 radiculopathies. The effects of longitudinal durotomy were also investigated in a controlled study involving 118 patients with laminoplasty.

RESULTS

The length ratio between the longest and shortest anterior rootlet in each cervical root showed fairly constant values. Clinically, the length of the shortest rootlet could be calculated using a myelogram. Radiographical findings in cases of postoperative radiculopathies suggested increased tension on roots outside the dural sac but not on rootlets inside the dural sac. Application of longitudinal durotomy in a type of lateral opening laminoplasty resulted in the disappearance of postoperative radiculopathy.

CONCLUSIONS

An extradural tethering effect was suggested as one mechanism leading to postoperative radiculopathy. Durotomy may be useful in the treatment of postoperative palsy.

The high hepatocarcinogen susceptibility of LEC rats is genetically independent of abnormal copper accumulation in the liver

We previously reported that LEC rats, which show a spontaneous occurrence of liver injury and hepatocellular carcinoma (HCC), are highly susceptible to chemical carcinogens such as diethylnitrosamine (DEN). Since abnormal copper accumulation in the liver of LEC rats was found to be a cause of liver injury, it is necessary to elucidate whether the carcinogen susceptibility of LEC rats is related to the accumulation of copper in the liver. In this study we have examined the relationship between the susceptibility of FI [LEC x LEA or LEC x Fischer 344 (F344)] and FI backcross rats to DEN and hepatic copper concentration, as copper accumulation has been demonstrated to be inherited as an autosomal recessive trait. The groups of F1 and F1 backcross rats were given a single intraperitoneal injection of DEN (20 mg/kg wt) and subjected to a modified Solt-Farber protocol for assaying glutathione S-transferase placental form (GST-P)-positive foci. The hepatic copper concentration was examined by atomic absorption. Although no F1 rats showed a high copper concentration in the liver, the numbers of foci were as high as those in LEC rats which accumulate copper. Backcross rats separated into high and low copper concentration groups at an almost 1:1 ratio, but there was no significant difference in the mean numbers of foci between these two groups. The results clearly indicate that the high susceptibility of LEC rats to DEN is genetically independent of copper accumulation in the liver. A possible dominant inheritance of this high carcinogen susceptibility was suggested. Biochemical measurement of cytochromes P450 and b5 in the liver of F1 rats indicated that alterations in drug metabolizing enzymes may be partially responsible for the high carcinogen susceptibility of LEC rats.

Role of copper accumulation and metallothionein induction in spontaneous liver cancer development in LEC rats

The LEC rat spontaneously develops liver cancer after suffering chronic liver injury caused by abnormal copper accumulation in the liver, but the role of copper accumulation in the induction of liver cancer remains obscure. We histochemically and biochemically examined the content of copper and metallothionein (MT), a cytoplasmic copper binding protein, in spontaneously developed preneoplastic and neoplastic liver lesions and compared them with those in the surrounding liver tissues. Histochemically, the majority of the preneoplastic liver lesions (68%) and liver cancers (59%) showed lower copper contents than the surrounding liver tissues and no lesions were shown to accumulate more copper than the surrounding tissues. A marked heterogeneity in copper staining was observed in cancer tissues. In contrast, these lesions showed an equal to higher MT content than their surroundings. Biochemical measurements of copper and MT in cancer tissues supported the histochemical findings. The bromodeoxyuridine (BrdU) labeling index was high in all cancer tissues and some of the preneoplastic liver lesions. Parts of the cancer tissues with negative or weak staining for copper were highly labeled with BrdU. Taking these results together, copper accumulation may exert a growth inhibitory effect on surrounding hepatocytes, whereas the hepatocytes in the liver lesions could proliferate, escaping from the effect of copper toxicity by increasing their MT induction and lowering copper accumulation. Thus, accumulation of copper may act as a promoting factor for the development of liver cancer in LEC rats by creating a selective growth environment.

Adamantane as a brain-directed drug carrier for poorly absorbed drug. 2. AZT derivatives conjugated with the 1-adamantane moiety

Five AZT (azidothymidine) prodrugs conjugated with the 1-adamantane moiety via an ester bond were synthesized to improve the transport of AZT into the central nervous system (CNS). In in vitro degradation studies with rat and human plasma, it was demonstrated that the prodrugs were degraded enzymatically and converted quantitatively to their parent drug. AZT. As assessed by octanol-buffer partitioning, the prodrugs were much more lipophilic than AZT and were expected to penetrate the blood-brain barrier (BBB) readily. In in vivo studies, in which the prodrugs were administered intravenously to rat, the prodrugs in brain tissue were detected at 7-18 times higher concentrations than AZT in spite of the negligible amount of the prodrug in the cerebrospinal fluid. These results indicate that the introduction to AZT of the 1-adamantane moiety results in the enhancement of the BBB penetration. This pharmaceutical approach would be beneficial for the efficient treatment of the CNS infection by human immunodeficiency virus.

The LEC rat: a model for human hepatitis, liver cancer, and much more

The LEC rat is an inbred mutant strain with spontaneous hepatitis isolated from Long-Evans rats. Since approximately 40% of LEC rats die of fulminant hepatitis, the rat serves an animal model for studying the pathogenesis and treatment of human fulminant hepatitis. The remaining 60% of LEC rats survive and develop chronic (prolonged) hepatitis and subsequently develop liver cancer. Therefore, the LEC rat serves an important animal model for studying the significance of chronic hepatitis in the development of human liver cancer, which often develops in association with chronic hepatitis. The LEC rat can also be used as an animal model of Wilson's disease, since recent studies have disclosed high copper accumulation in the liver and low ceruloplasmin concentration in the serum of this mutant rat.