A novel mutation at position +12 in the intron following exon 10 of the tau gene in familial frontotemporal dementia (FTD-Kumamoto)

Exonic and intronic mutations in the tau gene cause familial frontotemporal dementia and parkinsonism linked to chromosome 17. Here, we describe a new mutation, consisting of a C-to-T transition at position +12 of the intron following exon 10 of the tau gene in the Kumamoto pedigree, showing frontotemporal dementia. The mutation caused a marked reduction in melting temperature of the tau exon 10-splicing regulatory element RNA and a large increase in exon 10-containing transcripts. Brain tissue from affected individuals showed an abnormal preponderance of exon 10-containing transcripts that was reflected at the protein level by an overproduction of tau isoforms with four microtubule-binding repeats. Immunostaining revealed the presence of tau aggregates in degenerating neurons and glial cells. Isolated tau filaments had a twisted ribbon-like morphology and were made of hyperphosphorylated four-repeat tau isoforms. The additional mutation located dose to the splice-donor site of the intron following exon 10 of the tau gene supports the view that intronic mutations exercize their pathogenic effect by destabilizing RNA secondary structure.

[Evaluation of risks for postoperative pulmonary complications using a preoperative consultation system]

We retrospectively investigated the perioperative management and postoperative pulmonary complications of patients who had preoperative respiratory problems and consultations with anesthesiologists. These patients numbered eight hundred, 23.7% of all patients who had preoperative consultations, and 40.9% and 62.0% of the 800 had preoperative and postoperative respiratory management, respectively. Forty eight patients (6.0%) received postoperative artificial respiration. One hundred and twenty four patients (15.5%) had some respiratory complications post-operatively, and 5 patients (0.7%) died mainly because of the complications. In an evaluation of these patients with the modified predicted risk factors of Okutsu including the obesity factor and smoking history, there was no respiratory complication in patients under 14 points. Patients with high points of more than 20 included almost all of the patients (114 patients, 91.9%) who had postoperative respiratory complications. We conclude that our preoperative consultation system works well and that the modified predicted-risk factors for postoperative pulmonary complications is useful for the standardization and objectivity of preoperative patient evaluation.

Intraoperative enzyme-amperometric monitoring of extracellular glutamate concentration with a dialysis electrode in ischemic human brain

Changes in the extracellular concentration of glutamate in the brain ([Glu]e) were monitored continuously by an enzyme-amperometric technique employing a dialysis electrode during ischemia caused by isolation of the brain tissue in rats and human patients. In the rat (n = 10), the dialysis electrode was placed in the frontal cortex and the frontal lobe was transected. A transient sharp increase in [Glu]e was frequently observed during the transection. A biphasic elevation (a rapid increase followed by a slowly continuing increase) subsequently occurred with a latent period of 1-3 min after the transection of the rat frontal lobe. In patients (n = 7), the dialysis electrode was placed in tumor-free cortical areas which were planned to be resected together with gliomas. Progressive increases in [Glu]e were observed in all of the patients as the isolation of the brain tissue progressed. A biphasic increase, similar to that seen in the rat, was identified in 2 patients in whom the cortical area surrounding the dialysis electrode was rapidly isolated. The present enzyme-amperometric technique employing a dialysis electrode appears to be useful for detecting the occurrence of potentially harmful ischemia and for securing minimal metabolic stress caused during various surgical manipulations.

Lactotransferrin immunocytochemistry in Alzheimer and normal human brain

Lactotransferrin (LF) expression was investigated immunocytochemically in postmortem brain tissues of normal controls and patients with Alzheimer's disease (AD). The antibody to LF stained some neurons weakly in young adult brains, but it stained many neurons as well as the glia of all types in elderly brains. LF expression was greatly up-regulated in both neurons and glia in affected AD tissue. It was very strongly associated with such extracellular pathological entities as diffuse and consolidated amyloid deposits and extracellular neurofibrillary tangles. In addition, it was identified in a minority of intracellular neurofibrillary tangles, neuropil threads, and degenerative neurites. LF is an iron scavenger and a complement inhibitor. Up-regulation may be a defense mechanism in AD-affected brain tissue.

[Two cases of giant aneurysms arising from the distal segment of the anterior cerebral circulation]

Giant aneurysm arising from the distal segment of the anterior cerebral circulation is extremely rare, and only 14 cases of anterior cerebral circulation aneurysms have been reported in the literature. This report describes two cases of giant intracranial aneurysms, one arising from the distal segment of the middle cerebral artery, and the other from the azygos anterior cerebral artery. Although both of the patients started with intracranial hemorrhage, their surgical outcomes were good. The growth mechanisms of each aneurysm are discussed based on the clinical and pathological findings. Since the wall of the middle cerebral artery aneurysm showed granulomatous changes with infiltration of many inflammatory cells, the aneurysmal enlargement is considered to have resulted from chronic inflammation of the wall. In the case of anterior cerebral artery aneurysm, hemodynamic stress through the azygos artery may have caused the giant aneurysm. Operative indication for giant intracranial aneurysm is controversial. Since the surgical outcomes of reported cases are definitely better than those of the patients with proximal giant aneurysm, we conclude that giant aneurysm arising from the distal segment of the cerebral artery should be treated surgically.

[Clinicopathological studies of three cases of cerebral aneurysms associated with systemic lupus erythematosus]

We report three cases of ruptured cerebral aneurysms associated with systemic lupus erythematosus (SLE). A 52-year-old woman (case 1) with a fifteen-year history of systemic lupus erythematosus suddenly lost consciousness. She was admitted in a state of deep coma. A computed tomography (CT) scan revealed acute hydrocephalus and diffuse subarachnoid hemorrhage in the basal, interhemispheric and bilateral Sylvian cisterns. Fifteen years prior to this admission, cerebral angiograms demonstrated no cerebral aneurysm. She underwent ventricular drainage immediately. Postoperatively, her condition did not improve, and she died on the 18th day. During the autopsy, two saccular cerebral aneurysms were found: one aneurysm was at the right middle cerebral artery bifurcation, and another one was on the anterior communicating artery, which had disruption of the internal elastic lamina and medial smooth muscle, and infiltration of inflammatory cells. In the major cerebral arteries, for example the bilateral internal carotid arteries, disruption or dissection of the internal elastic lamina, intimal fibrosis and transmural infiltration of inflammatory cells were observed. The second patient, a 36-year-old woman with a six-year history of SLE, was admitted to our hospital with sudden severe headache. A CT scan showed subarachnoid hemorrhage, and cerebral angiograms disclosed saccular cerebral aneurysms on the anterior communicating artery and the left superior cerebellar artery, and a fusiform one on the left posterior cerebral artery. Surgery was not recommended because of her multiple medical problems. Her consciousness improved gradually over 2 months. She was transferred to the department of internal medicine for treatment of renal failure.(ABSTRACT TRUNCATED AT 250 WORDS)

The usefulness of ultrasonic microprobe imaging for endoscopic variceal ligation

OBJECTIVES

This study investigated whether ultrasonic microprobe (UMP) imaging was useful in judging the therapeutic effect of endoscopic variceal (EVL) on varices as well as assessing varices and surrounding vessels before and after EVL.

METHODS

UMP imaging was performed repeatedly safely and easily via the biopsy channel of an endoscope in 20 patients with esophageal varices. Using this modality in combination with our method of "intensive ligation," we treated esophageal varices successfully.

RESULTS

Before EVL, UMP imaging displayed esophageal varices, periesophageal collaterals, and the azygous vein as echo-free lumens. In 15 of 20 patients, UMP imaging clearly detected the perforating vein, one of the optimal ligation sites for EVL, connecting the varix and collateral vein. Just after EVL, UMP imaging revealed a hyperechoic change ("snow ball" sign or "snow channel" sign), indicating blood flow stasis in the esophageal varices. On subsequent EVL, UMP imaging showed the cross-sectional area of varices was undetectable (occluded) or partially detectaable. After repeated EVL (2.9 treatment sessions on average), UMP imaging, as well as endoscopy, indicated that almost all varices were eradicated (undetectable). However, UMP imaging demonstrated that neither collaterals nor the azygous vein had significantly changed in size.

CONCLUSIONS

This modern diagnostic modality provided a clinical adjunct to current endoscopy when observing esophageal varices and surrounding vessels before and after EVL to determine the need for additional therapy.

Escherichia coli dnaJ deletion mutation results in loss of stability of a positive regulator, CRP

The dnaJ deletion mutant K7052(lambda dnaK) has a temperature-sensitive defect in the synthesis of beta-galactosidase. We confirmed this operon-specific and temperature-sensitive defect in cell-free extracts prepared from the mutant cells and found that the missing factor was CRP. In the mutant, the cellular concentration of CRP was too low to allow the expression of the lac operon at a nonpermissive temperature. Introduction of a CRP over-producing plasmid into the dnaJ deletion mutant suppressed the defect of beta-galactosidase synthesis. The lower content of CRP in the mutant was found to result from extreme instability of the protein. These results strongly suggested that the heat shock protein dnaJ is involved in the stabilization (or degradation) of CRP.

[Primary central nervous system malignant lymphoma originating from the cerebellum and extending along the lower cranial nerves]

We report a case of primary central nervous system (CNS) malignant lymphoma of the central nervous system originating from the cerebellum and growing along the lower cranial nerves. A 67-year-old woman presented with hoarseness, vertigo, nausea, and vomiting. Gd-DTPA enhanced MRI showed a homogeneous enhanced mass lesion extending from the cerebellum to the medulla oblongata around the jugular foramen on the right side. Although pre- and intra-operative diagnosis had been schwannoma, histopathological examination revealed a B-cell, diffuse malignant lymphoma. The growth pattern of malignant lymphoma in the present case, which extended extra-axially, is considered to be rare. We discuss here the growth patterns and difficulties of diagnosis of primary CNS malignant lymphoma in this area.

Prodromal signs and clinical factors influencing outcome in patients with intraventricular rupture of purulent brain abscess

OBJECTIVE

To elucidate prodromal signs and clinical factors influencing the prognosis in patients with intraventricular rupture of brain abscess (IVROBA) to prevent and manage this catastrophic condition.

METHODS

In this study, 33 consecutive patients with IVROBA diagnosed by computed tomography (CT) were treated. Basic and therapeutic parameters were evaluated as independent predictive factors of a poor prognosis by using univariate analysis. The factors were statistically analyzed based on the interval between initial symptoms and IVROBA.

RESULTS

Patients with a good outcome were younger (<21 yr old) (P < 0.003) and had fewer complications after IVROBA (P < 0.03). For the most part, these patients had undergone aspiration for brain abscess with ventricular drainage combined with the immediate administration of appropriate intravenous and intrathecal antibiotics (P < 0.02). In just a short time, abscesses located in the parieto-occipital region ruptured into the ventricle (P < 0.004), and those with nonsterile cultures (P < 0.01) developed into IVROBA. Just before IVROBA, patients had severe headaches, signs of meningeal irritation, and a rapidly deteriorating clinical condition within 10 days after the signs of meningeal irritation developed. A CT scan obtained before IVROBA ascertained localized enhancement of the ventricular wall adjacent to the abscess.

CONCLUSION

Our findings suggest that signs of meningeal irritation and localized enhancement of the ventricular wall adjacent to the abscess, as observed on CT scans, preceded IVROBA. To decrease the mortality rate associated with purulent brain abscesses, signs forewarning of IVROBA should be recognized, and aggressive management of IVROBA should be initiated. Aggressive CT-guided aspiration of deep-seated abscesses, particularly in the parieto-occipital region, at the time forewarning signs of IVROBA are observed lead to the prevention of IVROBA and an improvement in outcome.

Immunologic reactions in amyotrophic lateral sclerosis brain and spinal cord tissue

Expression of proteins associated with immune function was investigated immunohistochemically in postmortem brain and spinal cord of patients with amyotrophic lateral sclerosis (ALS). Reactive microglia/macrophages displaying high levels of leukocyte common antigen (LCA), the immunoglobulin receptor Fc gamma R1, lymphocyte function associated molecule-1 (LFA-1), the complement receptors CR3 and CR4, the class II major histocompatibility complex molecules HLA-DR, HLA-DP and HLA-DQ and common determinants of the class I HLA-A,B,C complex were abundant in affected areas in ALS. These areas included the primary motor cortex, motor nuclei of the brain stem, the anterior horn of the spinal cord, and the full extent of the corticospinal tract. A significant number of T lymphocytes of the helper/inducer (CD4+) and cytotoxic/suppressor (CD8+) subtypes were observed marginating along the walls of capillaries and venules and extending into the parenchyma of affected areas. Clusters of complement activated oligodendroglia as well as degenerating neurites positive for C3d and C4d were frequently detected in ALS-affected areas. These data provide evidence of immune-effector changes in ALS. They are consistent with an autoimmune or slow virus theory of the disorder, but may reflect only secondary changes.

[Epidural buprenorphine does not improve diaphragmatic function after upper abdominal surgery]

We investigated the effect of epidural buprenorphine on diaphragmatic function using respiratory inductive plethysmography (RIP) in seven healthy patients after upper abdominal surgery. After surgery, changes of rib cage contribution to tidal volume (%RC) increased significantly from 25.3 +/- 7.3 (mean +/- SD) to 50.7 +/- 14.8% (P < 0.05). After the injection of epidural buprenorphine, visual analogue scale (VAS) score decreased significantly from 8.3 to 3.3 (P < 0.05). But, %RC was unchanged compared to the value before the injection. These results indicate that pain relief by epidural buprenorphine does not improve diaphragmatic function after upper abdominal surgery.

[Anesthetic management of a patient with Crow-Fukase syndrome complicated with severe heart failure]

A 31-year-old man with Crow-Fukase syndrome was scheduled for orthopedic surgery of the right lower limb. Preoperative examination revealed severe heart failure due to cardiomyopathy. Anesthesia was maintained with sevoflurane and nitrous oxide in oxygen, and supplemental fentanyl combined with continuous epidural block. During surgery, we evaluated cardiac function using transesophageal echocardiography. To maintain his cardiac function, intravenous dopamine and dobtamine were administered continuously, and the surgery was performed successfully. We must take care of cardiac function during anesthetic management of a patient with this syndrome.

[Catecholaminergic systems in the amygdaloid complex of SDAT and aged controls: tyrosine hydroxylase immunohistochemistry]

Catecholaminergic systems in the amygdaloid complex in patients with senile dementia of Alzheimer type (SDAT) and aged controls have been studied with tyrosine hydroxylase (TH) immunohistochemistry. TH-immunoreactivity was found in fibers in all subnuclei of human amygdala, although varying in density in the subnuclei. The most dense catecholaminergic innervation was observed in the central, basal, and cortical nuclei of amygdala. The prominent finding in the amygdaloid complex of SDAT was that swollen and bulbous TH-immunoreactive neurites were found in association with neuritic plaques, which have not, rarely if any, been found in controls. The numerical density of neurites was mostly in parallel with that of TH-immunoreactive fibers except for the central nucleus. Thus, it is suggested that a class of populations of TH-immunoreactive neurons are selectively affected in the amygdaloid complex in SDAT.

[A resolving sign of acute subdural hematoma: from report of two cases]

A 7-year-old-boy (Case 1) and a 60-year-old-man (Case 2) presented with rare spontaneous resolution of acute subdural hematoma (ASDH). They were admitted with consciousness disturbance, drowsy in Case 1 and sleepy in Case 2. Initial CT showed ASDH associated with a low density band between the hematoma and the inner wall of the skull base, combined with right parietal contusion in Case 2. Repeat CT showed that the hematoma had resolved spontaneously after a few hours, and the patients regained clear consciousness next day in Case 1 within a few days in Case 2 without surgical treatment. The mechanism of spontaneous resolution of ASDH was thought to involve pulsatile flow of cerebrospinal fluid (CSF) through the tear in the arachnoid membrane, resulting in redistribution and dispersal of the hematoma, and retrograde flow into the subarachnoid space. The characteristic feature of the CT findings, the low density band between the hematoma and the inner wall of the skull bone, probably shows this process. Spontaneous resolution of ASDH requires that the brain compensatory function maintains the normal outflow of CSF, and controls the intracranial pressure by CSF buffering, blood outflow via the venous system, and brain elasticity. The low density band may be a useful finding to distinguish cases with good and bad prognosis.

[Clinical evaluation of accuracy of a new disposable pump (Syrinjector) for continuous epidural infusion]

We evaluated the accuracy of a new disposable pump (Coopdech Syrinjector), which employed the negative pressure made by injecting fluid into the pump for continuous epidural infusion. Thoracic epidural catheter was placed at the T6-T8 level prior to the lung surgery. The continuous epidural infusion of 0.25% bupivacaine at 2 or 3 ml.h-1 was started immediately after the surgery. The residual volume of bupivacaine was recorded. From our results, the injection speed of Syrinjector was satisfactory for clinical use of continuous epidural infusion of bupivacaine. However, when this pump is reused or the volume of the residual local anesthetics is less than 10 ml, the infusion accuracy will be potentially imprecise.