Elevated 1-h plasma glucose following 75-g oral glucose load is a predictor of arterial stiffness in subjects with normal glucose tolerance

AIMS

The study aimed to investigate arterial stiffness in subjects with normal glucose tolerance.

METHODS

BMI, systolic blood pressure, fasting plasma glucose, lipid variables, ankle-brachial pressure index and brachial-ankle pulse wave velocity were measured in 2059 subjects from Takasaki city, located approximately 100 km north of Tokyo in Japan. Following a 75-g oral glucose tolerance test, only subjects with normal glucose tolerance were selected.

RESULTS

One-hour post-challenge plasma glucose levels were correlated with brachial-ankle pulse wave velocity values (r = 0.340, P < 0.0001). When subjects with normal glucose tolerance were divided into three groups-group 1 (1-h plasma glucose < 8.56 mmol/l, n = 1595), group 2 (1-h plasma glucose ≥ 8.56 and < 10.17 mmol/l, n = 334) and group 3 (1-h plasma glucose ≥ 10.17 mmol/l, n = 130)-the brachial-ankle pulse wave velocity of group 3 (1473 ± 322 cm/s) was significantly higher than that of group 2 (1355 ± 252 cm/s) and brachial-ankle pulse wave velocity of group 2 was also significantly higher than that of group 1 (1275 ± 212 cm/s).

CONCLUSIONS

We have identified that, in normal glucose tolerance, arterial stiffness is advanced in subjects with higher 1-h post-challenge plasma glucose in spite of the normal range for BMI, systolic blood pressure, fasting plasma glucose and lipid variables. Higher 1-h plasma glucose level is a risk factor for arterial stiffness in normal glucose tolerance.

Early-onset ataxia with ocular motor apraxia and hypoalbuminemia: the aprataxin gene mutations

BACKGROUND

Early-onset ataxia with hypoalbuminemia is regarded as a variant form of Friedreich ataxia in Japan. Early-onset ataxia with hypoalbuminemia and ataxia with ocular motor apraxia have been considered as the same clinical entity because of the recent identification of a common mutation in the aprataxin gene. A new clinical entity named early-onset ataxia with ocular motor apraxia and hypoalbuminemia (EAOH) has been proposed to explain these two diseases.

OBJECTIVE

To disclose the clinical features of EAOH and to identify the mutations in the aprataxin gene in six patients in four Japanese families with EAOH.

METHODS

The clinical features, laboratory findings, sural nerve biopsy results, and brain MRI or CT findings for these patients were evaluated, and molecular analysis was performed, which involved sequencing of the aprataxin gene directly or use of the subcloning method.

RESULTS

Cerebellar ataxia and peripheral neuropathy were noted in all six patients. Ocular motor apraxia was observed in five patients; two of these patients had obvious head thrust. Choreiform movements of the limbs and mental deterioration were observed in five patients. Although foot deformity was noted in five patients, kyphoscoliosis was noted only in one patient. In all patients, hypoalbuminemia and hypercholesterolemia were evident, and brain MRI or CT showed marked cerebellar atrophy. Nerve biopsy revealed depletion of large myelinated fibers in three of the five patients examined. Molecular analysis of the aprataxin gene revealed an insertion mutation (insT at nt167) and two missense mutations (A-to-G transition at nt80 and C-to-T transition at nt95, the former being novel).

CONCLUSION

We found clinical heterogeneity in the patients with EAOH in this study. With the disease course, the choreiform movements tended to reduce in degree, and hypoalbuminemia became evident. Molecular analysis identified one insertion and two missense mutations including a novel missense one, which was located at a highly conserved amino acid residue in the aprataxin gene product.

A large Japanese SPG4 family with a novel insertion mutation of the SPG4 gene: a clinical and genetic study

We studied a large Japanese family with autosomal dominant pure hereditary spastic paraplegia (ADPHSP) clinically and genetically. To date, seven loci causing ADPHSP have been mapped to chromosomes 14q, 2p, 15q, 8q, 12q, 2q, and 19q. Among these loci, the SPG4 locus on chromosome 2p21--p22 has been shown to account for approximately 40% of all autosomal dominant hereditary spastic paraplegia (ADHSP) families. Very recently, Hazan et al. identified the SPG4 gene encoding a new member of the AAA (ATPases associated with diverse cellular activities) protein family, named spastin. We found a novel insertion mutation (nt1272--1273insA) in exon 8 of the SPG4 gene in the present family. Our study is the first to confirm the causative mutation of the SPG4 gene in Japanese. Clinically, it is noteworthy that the disease progression in the patients of this family was slow in spite of the late onset, and more than half of the patients showed severe constipation in addition to pure spastic paraplegia.

[Anesthetic management for an adult patient with secundum atrial septal defect associated with a large left-to-right shunt]

We describe the case of a 68-year-old woman with secundum atrial septal defect associated with a large left-to-right shunt and congestive heart failure. The patient with a pancreatic tumor was scheduled for hepatic cholangiojejunostomy and cholecystectomy. To determine the ratio of pulmonary to systemic flow (Qp/Qs) as an indicator for the magnitude of left-to-right shunt, oxymetric catheters were placed in the superior vena cava and pulmonary artery. In addition, oxygen delivery was assessed using superior vena cava oxygen saturation (SsvcO2). Although the patient was anesthetized with high-dose fentanyl to supplement nitrousoxide and sevoflurane, the Qp/Qs markedly increased after skin incision. Epidural local anesthetic was then administered. The Qp/Qs decreased to the preoperative value and the hemodynamic condition was improved thereafter. The operative course was uneventful. This case illustrates the potential usefulness of continuous measurement of the Qp/Qs and SsvcO2 for anesthetic management of adult patients with secundum atrial septal defect.

[Anesthetic management of a patient with deep venous thrombosis using temporary inferior vena cava filter]

A patient with deep venous thrombosis caused by a huge uterine leiomyoma underwent abdominal hysterectomy. To prevent pulmonary thromboembolism, the patient received anticoagulant therapy until 6 hr before surgery and temporary inferior vena cava filter was placed. A combination of preoperative anticoagulant therapy and the filter placement during perioperative period enabled this patient to be successfully-managed.

[A case of free rupture of abdominal aortic aneurysm into the peritoneal cavity during posture change after induction of anesthesia]

We report a case in which posture change for radiography after induction of anesthesia caused free rupture of the abdominal aortic aneurysm (AAA) into the peritoneal cavity, resulting in shock, although in the patient an AAA had ruptured into only the retroperitoneal space and hemodynamics had been stable preoperatively. The massive bleeding was controlled with autotransfusion using a washing salvaging autotransfusion device and a roller pump for hemodialysis. In addition, international mild hypothermia was effective for protection of the brain from suspected ischemia during shock. Meticulous attention should be paid for anesthetic management of patients with ruptured AAA even if their hemodynamic status is stable.

Malposition of the epiglottis after tracheal intubation via the intubating laryngeal mask

The intubating laryngeal mask has been reported to be a successful method of tracheal intubation although advancement of the tracheal tube via the laryngeal inlet into the trachea cannot be seen. Damage to the larynx or other tissues may occur during blind passage of a tracheal tube. We report a case in which the tracheal tube, advanced blindly, tucked the epiglottis into the laryngeal inlet, resulting in oedema of the epiglottis. This case illustrates the potential for airway obstruction after extubation when using the intubating laryngeal mask as a blind intubation guide.

[Anesthetic management of a patient with Bartter's syndrome]

A 48-year-old woman with Bartter's syndrome underwent right mastectomy under general anesthesia. Her operative course was uneventful. She was preoperatively complicated with severe hypokalemia but had no signs and symptoms of hypokalemia. In anesthetic care of patients with Bartter's syndrome, even when they have no symptoms of hypokalemia, the meticulous intravenous administration of potassium chloride is required in order to maintain the preoperative level of the serum potassium during anesthesia. In addition, attention should be paid to factors causing an additional reduction in the serum potassium concentration, such as alkalosis, elevated beta 2-adrenergic activity, increased availability of insulin and hypothermia.

[Spinal microsurgery at the thoracic to sacral level in the "prone-oblique" position]

Until the present time, almost all posterior approaches to the thoracic to sacral region have been made in either the knee-elbow or the prone position. Those positions, however, have potential disadvantages such as respiratory suppression and/or disturbance of venous return due to compression of the anterior chest and belly. In order to avoid the above mentioned disadvantages, the patient was laid on the operating table in a "Prone-Oblique" position, with the body rotating about 40 degrees around the long axis. The authors performed, with successful results, spinal operations via the posterior route in the "Prone-Oblique" position in 30 cases. An illustrative case was presented of a metastatic intramedullary tumor at the T11/12 level from an unresectable mammary cancer. The cancer had infiltrated and bulged out of the left anterior chest wall so severely and extensively that an operation in the conventional position was impossible. The metastatic tumor was totally and successfully removed via the posterior approach in the "Prone-Oblique" position without any complications related to the position. This "Prone-Oblique" position seems to be physiologically suitable, giving rise to no harmful compression of any part of the patient's body and it provides the surgeon a comfortable posture and a good operative view during microsurgery.

[Radical endovascular surgery of a huge cavernous internal carotid artery aneurysm of an aged patient]

A case of a huge aneurysm of the cavernous portion of the internal carotid artery (ICA) is reported. The aneurysm was successfully treated by endovascular surgery. A 78-year-old woman presenting with mild headache and cavernous sinus syndrome on the left side was incidentally disclosed to have a huge aneurysm at the cavernous portion of the left ICA by MRI and MRA. An angiogram revealed that the aneurysm had a broad neck. In view of patient's age, concomitant coronary ischemia and wide aneurysmal neck, endovascular surgery under local anesthesia was thought to be the treatment of choice. The aneurysmal sac was completely embolized with platinum coils and the ICA by a balloon proximal to the aneurysm. Over the 5 months period, the patient's symptoms has all disappeared save for mild abducens palsy. It is believed that neck clipping is the method of treatment of intracranial aneurysms. However, endovascular surgery is less invasive and may be applicable to some of high risk patients.

[A case of pituitary apoplexy: remarkable improvement of visual acuity and field by surgical intervention at the subchronic stage]

A case is reported of a pituitary apoplexy which shows remarkable improvement of visual acuity and field by transsphenoidal surgery performed 33 days after hemorrhage. Possible factors contributing to this excellent surgical outcome are speculated about as follows; atrophic brain (wide suprasellar cistern), destruction of the sella floor by the tumor (infrasellar/extracranial decompression), no vasospasm (pure intracapsular hemorrhage), no hypopituitarism, less invasive operation (transsphenoidal surgery), and so on. Transsphenoidal surgery is thought to be worth performing for pituitary apoplexy, even if timing for the operation is later than the acute stage and even if initial visual impairment is severe.

[Usefulness of transcranial magnetic stimulation in the objective assessment of therapy for adrenoleukodystrophy]

Adrenoleukodystrophy (ALD) is a hitherto untreatable, X-linked recessive disorder of the central nervous system characterized by the systemic accumulation of very-long-chain fatty acids. Although various treatments have been proposed, objective evidence of their efficacy is insufficient. This is partly due to the absence of an appropriate method for evaluating the functions of the central nervous system (CNS). In this study, we took up the central motor conduction time (CMCT) as an index of the CNS functions, and measured it in two patients with ALD under steroid pulse therapy to know if this parameter is useful in assessing the effects of therapy. The right and the left motor cortex was stimulated separately with a MAGSTIM 200 magnetic stimulator, using a round coil of 9cm mean diameter to stimulate the hand area or a double cone coil to stimulate the leg area. CMCT, the time an impulse takes to travel from the motor cortex to the anterior horn cells in the corresponding region, was measured by a combination of transcranial magnetic stimulation (TMS) and F wave technique. Before treatment, CMCT to the cervical cord was prolonged slightly in both patients; CMCT to the lumbar cord was prolonged slightly in one and moderately in the other. After repeated steroid pulse therapy, a definite improvement, although partial and transient, was observed in either case. TMS thus seems to be useful not only for detecting functional derangement of the pyramidal tract but for evaluating the efficacy of therapy for this disease.

Adrenal chromaffin cells transdifferentiate in response to basic fibroblast growth factor and show directed outgrowth to a nerve growth factor source in vivo

Chromaffin cells exposed to basic fibroblast growth factor (bFGF) in vitro express characteristics of sympathetic neurons, extend neurites, and become dependent on nerve growth factor (NGF) for survival. We explored whether the growth factor responsiveness of chromaffin cells could be exploited to enhance the transdifferentiation, neurite outgrowth and functional efficacy of chromaffin cells implanted into rats with unilateral 6-hydroxydopamine lesions. Cografts of neonatal chromaffin cells and fibroblasts genetically modified to produce bFGF were placed into the dopamine-depleted striatum of adult rats. Either control-transfected or NGF-producing fibroblasts were then transplanted 1 mm distal to the cograft. Chromaffin cells transdifferentiated under the influence of bFGF, as indicated by the growth of neurites and the expression of neuron-specific proteins. Distal grafts of NGF-producing fibroblasts successfully induced chromaffin neurites to traverse through the host parenchyma to the NGF source. In the absence of NGF fibroblast grafts, neither neurite extension nor good, long-term survival of the chromaffin-derived neurons was observed. Assessments of apomorphine-induced rotational behavior 2- and 4-weeks postgrafting revealed no behavior improvements in any of the groups. These results indicate that localized sources of growth factors are effective in inducing the transdifferentiation of grafted chromaffin cells as well as the extension of chromaffin-derived neurites into the host parenchyma. Such chromaffin cell-derived neurons are, however, functionally ineffective in this rat model of Parkinson's disease. Whether the lack of behavioral improvement reflected the tropic growth of neurites to an inappropriate striatal region or the noradrenergic nature of the chromaffin cell-derived neurons remains to be clarified. Nonetheless, these results caution that promoting transdifferentiation and neurite extension from engrafted chromaffin cells may not be sufficient to achieve desired functional effects of such grafts.

[Neck clipping of an aneurysm at the basilar artery-anterior inferior cerebellar artery via presigmoid-transmastoideal approach]

A 51-year-old man presented severe disturbance of consciousness and massive subarachnoid hemorrhage. Angiography disclosed an aneurysm at the ventral bifurcation of the basilar and anterior inferior cerebellar arteries. Neck clipping and additional wrapping/coating were performed via the presigmoid-transmastoideal approach with successful result. The operative procedure was described and advantages of this approach were discussed.

Enhanced survival and neuronal differentiation of adrenal chromaffin cells cografted into the striatum with NGF-producing fibroblasts

Although adrenal medullary chromaffin cells have been used extensively for intracerebral grafting, their survival has generally been poor. Improved survival of the implanted cells has been achieved by exposing the chromaffin cells to NGF in vivo. Culture studies have shown, however, that chromaffin cells are converted into sympathetic neurons when NGF is included in the medium. The degree to which such a transdifferentiation may occur in vivo has not been determined. We assessed the effects of cografting chromaffin cells with primary fibroblasts genetically engineered to express NGF. Chromaffin cells from 10 d old rats were implanted with NGF-producing or beta-galactosidase-producing primary fibroblasts (control fibroblasts) into the striatum of 6-hydroxydopamine treated adult rats of the same strain. Eight weeks postgrafting, chromaffin cells cografted with NGF-producing fibroblasts displayed many of the features of mature sympathetic neurons such as large somata, long processes, transmitter vesicles similar to those found in neurons, and positive immunolabeling for the neuronal markers neurofilament, MAP2 and SCG10. Chromaffin-derived neuron number was also significantly enhanced in the presence of NGF-producing fibroblasts. While control fibroblasts were also found to increase chromaffin cell number above that of chromaffin cells grafted alone, the control fibroblasts did not induce neuronal transdifferentiation. These results demonstrate that chromaffin cells cografted with NGF-producing fibroblasts undergo transdifferentiation in vivo and express many characteristics of mature sympathetic neurons. The consequences of this transdifferentiation on the long term survival and function of the transplanted cells in vivo remain to be clarified.

Ossified spinal meningioma en plaque

Ossified spinal meningiomas alone are uncommon lesions and spinal meningiomas en plaque are even more. A rare case is presented of ossified meningioma en plaque in the midthoracic spine, which was totally removed. Characteristics of this tumor with reference to relatively pathognomonic neuroimagings are discussed. Microsurgical outcome of this type of tumor is expected to be good.

Expression of antitumor response. Role of attachment and viability of bacillus Calmette-Guérin to bladder cancer cells

BACKGROUND

Antitumor effects of Bacillus Calmette-Guérin (BCG) against superficial urinary bladder cancer is known to be strong when BCG is directly infused into the bladder cavity. For expression of that effect, attachment of BCG to tumor cells is reported to be essential as the first step. Our study was conducted to elucidate the significance of attachment of BCG to tumor cells in inducing the antitumor effect.

METHODS

BCG, Tokyo 172 strain, in the form of live bacilli, lyophilized bacilli, or autoclaved bacilli was co-cultured with MBT-2, mouse-origin transitional cell cancer cells. Various preparations of BCG were mixed with MBT-2 cells and transplanted to male C3H/He mice to see tumor growth-inhibiting effect.

RESULTS

Both live and lyophilized BCG attached strongly to MBT-2 cells. The maximal attachment to the cells with live BCG occurred 24 hours earlier than with lyophilized BCG. When BCG was autoclaved, it lost the ability to attach to the cells. Lyophilized or autoclaved BCG exerted a marked tumor growth-inhibiting effects. This effect was equal to the Tokyo 172 strain and the Armand Frappier Canada strain. Histologically, a high degree of infiltration by macrophages was seen.

CONCLUSIONS

The results indicated that coexistence of BCG, even as killed by autoclaving, with tumor cells activates local immunity. Accordingly, the significance of the attachment of BCG to tumor cells in intravesical infusion therapy is surmised to lie in the fact that it results in retention of the BCG at the reaction site. This may provide a clue on how to approach future development of safer and more stable BCG-derived antitumor drugs.

Preventive superficial cervical plexus block for postoperative cervicocephalic pain in neurosurgery

Eighty-six (54%) of a series of 160 patients who underwent neurosurgery experienced postoperative cervicocephalic pain. We performed a superficial cervical plexus block (SCPB) immediately after operation in the subsequent 240 patients, in which the incidence of postoperative cervicocephalic pain was reduced to 27% (65 patients), and the intensity of pain was apparently milder. SCPB is a worthwhile procedure to prevent postoperative cervicocephalic pain.

[Idiopathic normal pressure hydrocephalus in elderly patients: its pathophysiology and diagnosis]

We described 10 cases of idiopathic normal pressure hydrocephalus (NPH) in elderly patients who had good results after shunting. Retrospective analysis of our cases offers the following results which indicate the pathogenesis and surgical selection of idiopathic NPH. 1) Most of the patients had risk factors of ischemic cerebrovascular disease and had multiple small ischemic lesions such as lacunae. 2) Cerebrospinal fluid (CSF) pressure is below 20mmHg in all cases and its response to acetazolamide loading was suppressed or almost lost in most of cases. 3) The volume of the lateral ventricle was slightly reduced after the effective operation. 4) Some of the patients showed clinical improvement even if they had symptoms for more than 2 years before treatment. Two primary theories exist concerning the cause of NPH. One is extraventricular obstruction to CSF flow at the level of the arachnoid villi or the basal cistern. The other is periventricular white matter ischemic damage which decreases the tensile strength of the ventricular walls and leads to ventricular dilatation. Tangential periventricular shearing force due to ventricular dilatation produces the symptom of NPH. Our results support these descriptions as the causes of idiopathic NPH in elderly patients. We noticed, firstly, involvement of the ischemic risk factor. Other findings implied decreased elasticity or compliance of the brain and the loss of the autoregulatory properties of cerebral circulation which accelerate the ischemic damage to the periventricular white matter. In understanding the etiology, it is important to know the fragility of the aged brain and the mechanical and hemodynamic stress to which it is subjected.(ABSTRACT TRUNCATED AT 250 WORDS)

Hematological studies on naturally occurring substances. VI. Effects of an animal crude drug "chan su" (bufonis venenum) on blood coagulation, platelet aggregation, fibrinolysis system and cytotoxicity

During the screening test of the animal crude drug "Chan su" (Chinese name, toad-cake), the venom of Bufo bufo gargorizans CANTOR (Bufonidae), on blood coagulation, platelet aggregation, fibrinolysis system and cytotoxicity, the ethyl acetate extract showed promotive action on platelet aggregation and remarkable cytotoxic activity on HeLa-S3 cells. Nine kinds of bufadienolides were isolated from the ethyl acetate extract by bioactivity-guided fractionation and were identified by chemical and spectral analysis.

Differential roles of the caudate nucleus and putamen in motor behavior of the cat as investigated by local injection of GABA antagonists

In order to reveal a functional difference between the two distinctly separate nuclei of the striatum, i.e. the caudate nucleus (Cd) and the putamen (Put), we studied the effects of local bicuculline (BIC) and picrotoxin (PTX) injection into these nuclei on the motor behavior in the cat. The extent of diffusion of the injected BIC could be approximated by determining the extent of spreading of the dye fast green FCF (FCF) mixed with BIC solution since the extent of diffusion of radioactive [3H]BIC mixed with BIC and FCF solution was almost the same as that of FCF.BIC and PTX are GABA antagonists and are assumed to activate efferent neurons of the Cd and Put by removing the action of GABA-ergic inhibitory synapses on them. A total of 28 BIC and 22 PTX injections was made in 20 adult cats, 22 aimed at the Cd and 28 at the Put. Injection of BIC or PTX to either the head or body of the Cd unilaterally induced locomotor hyperactivity without any postural asymmetry or circling tendency. When BIC or PTX was injected into the Put, dystonic movements (dystonia) towards the contralateral side appeared frequently in the neck and trunk. Even though the injected BIC or PTX often spread to the external segment of the globus pallidus, claustrum, or anterior sylvian gyrus, none of these areas was consistently associated with dystonia. These results demonstrate that the Cd and Put are differentially associated with locomotor and postural functions.

Enhanced survival of cultured dopamine neurons by treatment with soluble extracts from chemically deafferentiated striatum of adult rat brain

A soluble fraction was extracted from a chemically deafferentiated striatum of adult Wistar rats after unilateral lesioning of the nigrostriatal pathway by 6-hydroxydopamine (6-OHDA) injection. The soluble extract from the lesioned side enhanced the survival of cultured mesencephalic dopamine (DA) neurons of 14-day-old rat embryos as evidenced by quantitative counting of tyrosine hydroxylase-like immunoreactive cells. The neurotrophic activity of this striatal extract for DA neurons was highest 14 days after 6-OHDA injection and became negligible in 28 days. The extract showed no promoting effects on cultured gamma-aminobutyric acid (GABA)-containing mesencephalic neurons. These observations indicate that the striatum of adult rats may initiate de novo synthesis of trophic substance(s) for DA neurons but not for GABA neurons when subjected to nigral dopaminergic deafferentiation.

Marked decrease of mitochondrial DNA with multiple deletions in a patient with familial mitochondrial myopathy

Muscle mitochondrial DNA (mtDNA) from a patient with mitochondrial myopathy was examined by Southern blotting. Her family history suggests autosomal dominant inheritance of this disorder. In contrast to other cases of this myopathy that are associated with a compensatory increase of mitochondria, in this patient, the content of mtDNA was markedly decreased (15% of controls), whereas protein of the ATP synthase beta-subunit was not decreased appreciably as judged by Western blotting. In addition, the mitochondrial DNA had multiple deletions, which were located between the replication origins of the heavy strand and light strand.

Interleukin 3 as a trophic factor for central cholinergic neurons in vitro and in vivo

We have found that interleukin 3 (IL-3), a growth factor for hematopoietic cells, is a novel trophic factor for mouse and rat central cholinergic neurons. It enhanced neurite outgrowth and elevated choline acetyltransferase activity. The effect seems to be specific for cholinergic neurons, since somatostatin release and glutamic acid decarboxylase and 2',3'-cyclic nucleotide 3'-phosphodiesterase activities were not significantly influenced by IL-3. In vivo, IL-3 was infused into the lateral ventricles of rats after unilateral axotomy of the septohippocampal pathways. Two weeks later, the IL-3-treated animals showed significant numbers of acetylcholinesterase-positive neurons remaining in the septal region.

Impairment of active avoidance produced after destruction of pedunculopontine nucleus areas in the rat

Pedunculopontine nucleus areas were lesioned bilaterally in the rat by local injection of kainic acid. When rats so treated were tested for active avoidance behavior in shuttle boxes we found that their avoidance acquisition was completely abolished, whereas their intertrial locomotor activity and escape behavior were not affected. In the lesioned rats, choline acetyltransferase activity in the medial thalamus and substantia nigra decreased, but not in the lateral thalamus, hippocampus, or cerebral cortex. These findings suggest that the cholinergic pedunculopontine-medial thalamus projection plays an important role in memory acquisition in the rat.

Activation of mesencephalic dopamine neurons by chemical stimulation of the nucleus tegmenti pedunculopontinus pars compacta

Unilateral stereotaxic microinjection of a small amount of kainic acid (KA) into the nucleus tegmenti pedunculopontinus pars compacta (TPC) of male Wistar rats produced constant ipsiversive circling behavior. The rate of the TPC-derived circling was significantly attenuated by blocking agents of dopamine systems, including haloperidol and alpha-methyl-tyrosine (both injected intraperitoneally) and also 6-hydroxydopamine (injected into the bilateral medial forebrain bundles). Administration of norepinephrine antagonists (phenoxybenzamine hydrochloride and DL-propranolol) had no effect on the rate of the TPC-derived circling. Bilateral preinjections of atropine sulfate into the ventral midbrain tegmentum, including the ventral tegmental area and the pars compacta of the substantia nigra, significantly attenuated the rate of the circling. The unilateral KA injection into the TPC dramatically increased the ratio of HVA + DOPAC/dopamine, an indicator of dopamine turnover, in the nucleus accumbens as well as in the striatum bilaterally. The increase of the ratio in the nucleus accumbens was selectively suppressed by pretreatment with atropine sulfate administered into the bilateral ventral midbrain tegmentum. These facts indicate: (1) the TPC-derived circling behavior is mediated by the dopamine system, (2) the chemical stimulation of TPC by KA might produce an activation of midbrain dopamine neurons by excitatory TPC efferents to the dopamine neurons and enhance the dopamine turnover in the nucleus accumbens as well as in the striatum, (3) the excitatory TPC efferents may be muscarinic cholinergic in accordance with previous reports.

Neurophysiological analysis of ataxia in capsular ataxic hemiparesis

A quantitative analysis of ataxia and the readiness potential were studied in four cases of ataxic hemiparesis resulting from a small infarct in the posterior limb of the internal capsule. The ataxia appeared to be the result of involvement of the corticopontine tract originating from the precentral region (areas 4 and 6) at this level. The voluntary movements of the affected limbs were characterized by slowness and irregularity similar to those seen in cerebellar ataxia. The weakness per se was not such that it could account for the ataxia. The dentato-rubro-thalamo-cortical system did not appear to be significantly involved on the basis of normal readiness potentials.

Long-term effect of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) on striatal dopamine content in young and mature mice

Long-term effects of MPTP on striatal dopamine (DA) content and the influence of aging on the recovery were investigated in mice. Male C57BL/6J mice, young (2-month-old) and mature (10-month-old), were used. Two different dosage schedules of MPTP, i.e., 4 doses subcutaneous injections of 20 mg/kg each, and 4 doses subcutaneous injections of 40 mg/kg each, were given to both young and mature mice at 12-h intervals. Assays of striatal DA and 3,4-dihydroxyphenylacetic acid (DOPAC) content were performed 1 week, 1 month, 2 months, and 3 months after the last injection of MPTP. MPTP produced a marked reduction (-75% to -80%) of striatal DA content in both young and mature mice 1 week after the last injection of MPTP. In young mice, the striatal DA content showed a partial recovery in the subsequent stages studied. In contrast, no apparent recovery occurred in mature mice until as long as 3 months after the last injection. The results suggest that mice have a capacity for partial recovery of the striatal DA contents which was depleted by MPTP, and this capacity for recovery appears to be impaired in mature mice.

Changes in gamma-aminobutyrate, glutamate, aspartate, glycine, and taurine contents in the striatum after unilateral nigrostriatal lesions in rats

Contents of five amino acids (gamma-aminobutyrate (GABA), glutamate, aspartate, glycine, and taurine) were assayed in the rat striatum in which nigrostriatal pathways were unilaterally destroyed by 6-hydroxydopamine. GABA content in the operated side was significantly increased 1 month after the surgery compared with that in the nonoperated side. Contents of four other amino acids assayed did not change significantly. Among possible mechanisms for this elevation we postulated that sprouting of the GABAergic terminals in the striatum would be most probable.

[Electrophysiological identification of neurons of the substantia innominata]

Recently in senile dementia of Alzheimer type, neuronal loss of cholinergic neurons in the substantia innominata is described. However these findings are based on morphological studies and, so far, these neurons have not been identified physiologically. In this study we tried to record these neurons electrophysiologically by antidromic activation. Cats were anesthetized with sodium pentobarbital and paralyzed with gallamine triethiodide. Three arreys of 3 or 4 silver-ball stimulating electrodes were fixed to the surface of the cerebral cortex. Each electrode was stimulated by rectangular pulses of 1 msec duration. Recording electrodes were glass micropipettes filled with 2 M NaCl saturated with fast green FCF and inserted into the ipsilateral substantia innominata stereotaxically. Twenty-eight neurons were constituted of mainly negative component; suggesting that they were recorded from cell bodies, not from axons. Also they responded in an all-or-none manner and showed constant latencies when stimulus intensities were at threshold level. When paired stimuli were applied, the latency of the action potential to the second stimulus was equal to that of the first one. These neurons were, therefore, considered to be activated antidromically. These neurons had axons of very slow conduction velocities. They are divided into two groups according to conduction velocities. The first group had mean conduction velocity of 2.3 m/sec and they responded to rather high frequency stimuli. The second group had mean conduction velocity of 1.0 m/sec and neurons belonging to this group showed quite long refractory periods. Based on conduction velocity analysis, the former is thought to include neurons with myelinated axons and the latter those with unmyelinated ones.(ABSTRACT TRUNCATED AT 250 WORDS)

Choriocarcinoma arising from the pituitary fossa with extracranial metastasis: a review of the literature

Since Askanazy's first report on a case of primary intracranial choriocarcinoma in 1906, more than 60 cases have been reported so far. We add to that a case of intrasellar choriocarcinoma with suprasellar extension: A 12-year-old girl showed cranial nerve palsies, hypopituitarism, and abnormally high titers of human chorionic gonadotropin (HCG) in blood and in cerebrospinal fluid (CSF). She died 3 months after surgery. At autopsy, an intra- and suprasellar choriocarcinoma, which penetrated through the clivus into the cerebellopontine angle and metastasized remotely to the lungs, was confirmed. This rare case is presented with a thorough review of the literature.