Collagen abnormalities in the spinal cord from patients with amyotrophic lateral sclerosis

During the last 10 years, we have demonstrated morphological and biochemical abnormalities of skin extracellular matrices in amyotrophic lateral sclerosis (ALS). However, currently little is known concerning collagen of the spinal cord in ALS. We measured the amount of collagen and characterized collagen at light and electron microscopic levels in posterior funiculus, posterior half of lateral funiculus and anterior horn of cervical enlargement of the spinal cord obtained from ten patients with ALS, 11 patients with other neurologic diseases (control group A), and ten patients without neurologic ones (control group B). In posterior half of lateral funiculus and anterior horn, (1) by light microscopy, there was no significant difference in vessel wall area between ALS patients and control groups A and B; (2) ultrastructurally, collagen bundles were more fragmented and widely separated, and the fibrils were randomly oriented in the perivascular space of capillaries in ALS patients, which were not observed in any areas of control groups or in posterior funiculus of ALS patients; and (3) the collagen contents in ALS were significantly lower (P<0.001 and P<0.001, respectively) than those in control groups A and B. Fragmented and widely separated collagen bundles in the interstitial tissue surrounding capillaries and markedly decreased amount of collagen in posterior half of lateral funiculus and in anterior horn of ALS could be related to the degeneration of the upper and lower motor neurons in the spinal cord in ALS, that is, selective neuronal vulnerability in ALS.     

Development of the brainstem: assessment by MR imaging

The morphological development of the brainstem was studied by means of MR imaging. The subjects were 74 cases ranging in age from 4 months to 16 years, and 6 adult cases. The brainstem development was rapid until 4-6 years of age and thereafter it slowed down. That is the brainstem showed exponential growth (w', t', v and u). The relationship between brainstem growth and the cranium size was divided into 4 types as follows: 1) linear increase with development (s/T-O), 2) plateau (w/T-I and v/RTP-LTP), 3) down and up (u/RTM-LTM and z/RTM-LTM) and 4) exponential (t/T-P). In the values of v, z (the size of the brainstem in axial view) and t/T-P (the ratio of the midbrain and the cranium size in sagittal view), there were significant sex differences for cases of 10-16 years old. These values in male subjects were greater than those in female subjects (v, p less than 0.05, z, p less than 0.01, and t/T-P, p less than 0.05). That is the brainstem in male subjects was greater than that in female subjects.     

Primary brain stem lesions caused by closed head injuries

Traumatic lesions of the brain stem are of two types: primary, which are considered to be caused at the moment of impact, and secondary, associated with supratentorial mass lesion. Of the 239 patients with a serious head injury who showed a severe disturbance of consciousness upon admisision and who had CT scan carried out immediately, 21 cases were considered to have a primary brain stem lesion with initial CT scan. A primary brain stem lesion was found in 21 of 239 (8.8%) of patients with serious head injury. Their injuries were caused primarily by traffic accidents. Sixteen of the 21 cases showed not only brain stem lesions but also other brain injuries such as cerebral contusion of the white and gray matter, callosal injury, intraventricular hemorrhage, and subarachnoid hemorrhage, which are considered to be caused by a diffuse shearing injury. Five cases who showed a single injury to the brain stem with no other brain lesions were considered to have a pure brain stem lesion. Primary brain stem lesions were observed on the dorsal side of the midbrain, where they can be differentiated from secondary brain stem lesions. These lesions are considered to result from the shearing mechanism in and around the brain stem very close to the tentorial edge, or to an injury of the lower brain stem by hyperextension of the cervical vertebrae. The prognosis of patients with a primary brain stem lesion was usually unfavorable, except in those with a single brain stem lesion.     

Conditions of Alzheimer-type dementia in the old-old and oldest-old patients with special reference to extreme conditions of brain aging

A neuropathological study on 1540 consecutive autopsy brains ranging from 60 to 107 years of age revealed the following points. (1) Of the of the demented cases of the plaque-predominant type, 93% were complicated with multiple tiny cortical infarcts. They showed a tendency for dementia to develop before or after the appearance or worsening of a systemic disorder such as cardiovascular disease, respiratory infection and cancer. However, there was no case showing Alzheimer-type dementia (ATD). (2) The plaque-predominant type might be an extreme condition of brain aging in terms of senile plaques (SP). It is likely that although the pathological appearance of SP alone is not responsible for dementia, its coexistence with multiple cortical infarcts could be the cause of dementia. Therefore, this type should be distinguished from ATD. (3) Primary hippocampal degeneration could also be an extreme condition of brain aging in terms of neurofibrillary tangles. This condition was different pathologically from the hippocampal lesion in ATD. (4) Several characteristics of old-old and oldest-old patients were clarified.     

Autoperfusion balloon catheter for treatment of vertebral artery stenosis

Percutaneous transluminal angioplasty (PTA) of the vertebral artery was performed with an autoperfusion balloon catheter in five patients. There were no complications in the form of embolic episodes or neurological deficits due to brain ischaemia during inflation. In critical cases with insufficient collateral circulation during temporary occlusion, the use of an autoperfusion balloon catheter may expand the indications for PTA in patients with ischaemic cerebrovascular disease.     

Treatment strategies for hepatic metastasis from colorectal cancer

Hepatic micrometastases of the parenchyma adjacent to a macroscopic lesion were detected in 17 of 31 resected liver metastases. Fifty-nine micrometastatic lesions were detected in total; 26 lesions were situated in the portal vein (PV), 22 in the central vein (CV), 5 in the bile duct (BD), and 6 in the sinusoid (SS). A histological study confirmed the direct invasion of the macrometastatic cancer cells into the adjacent PV, CV, BD, and SS. According to the tumor doubling time, the mean diameter of the macrometastases in 19 remnant livers was calculated to have been 0.57±0.87 cm at the time of the primary resection. The calculated diameter of 3 of these 19 macrometastases was found to be less than 0.01 cm, the minimum implantable size, indicating that the cancer recurrence in these specimens may have developed from macroscopic metastatic lesions as a satellite, and not from the primary tumor. In 13 patients who received doses of 5250 mg or more of 5 fluorouracil (FU) via the hepatic artery, the cumulative disease-free rate 2 years postoperatively was 100%; this value was 47.6% in 11 patients who received less than 5250 mg of 5 FU via the hepatic artery, and 0% in 39 patients who received no chemotherapy (P<0.005). These results suggest that anatomical hepatic resection for satellite lesions, combined with prophylactic hepatic arterial chemotherapy for micrometastases, decreases the recurrence rate of hepatic metastases in the remnant liver.     

Effects of isoflurane on oxygenation during one-lung ventilation in pulmonary emphysema patients

Background: Hypoxic pulmonary vasoconstriction has an important role in human one-lung ventilation (OLV) in the lateral decubitus position under general anesthesia. During OLV, inhalational anesthesia may inhibit hypoxic pulmonary vasoconstriction and the decrease in arterial oxygenation. We studied the effect of isoflurane administration on arterial oxygen tension in chronic obstructive pulmonary disease patients.
Methods: Ten patients who had thoracoscopic laser ablation of bullous emphysema were studied. Patients received 2% isoflurane in oxygen from induction until the first 20 min of OLV in the lateral decubitus position, then were switched to 1% isoflurane lasting 20 min and next were switched to 0.5% isoflurane lasting 20 min. After each 20-min inhalation, pulmonary and hemodynamic parameters were measured. The given concentrations for isoflurane were merely vapor meter concentrations.
Results: PaO₂/FIO₂, Qs/Qt respiratory rate peak inspiratory pressure and PaCO₂ showed no significant changes at each point of isoflurane. Expiratory tidal volume significantly decreased (P<0.05) with 0.5% isoflurane compared to that with 2% isoflurane. Cardiac output, mean arterial pressure, mean pulmonary arterial pressure, systemic vascular resistance and pulmonary vascular resistance showed no significant changes at each point of isoflurane.
Conclusions: In patients with pulmonary emphysema, arterial oxygenation is not affected by low isoflurane concentration during OLV in the lateral decubitus position.