Exogenous microglia enter the brain and migrate into ischaemic hippocampal lesions

We compared migration of systemically injected microglia into normal brain vs. ischaemic brain using a model of ischaemic hippocampal lesion. Microglia were labeled by a fluorescent dye using our standard phagocytosis procedure of microscopic particles and then injected intra-arterially into Mongolian gerbils subjected to ischaemia reperfusion neuronal injury. Delayed death of pyramidal neurons was confirmed by conventional histological analysis and dUTP nick end labeling (TUNEL) method. Clusters of dye-tagged cells migrating into the hippocampal ischaemic lesions were confirmed histochemically to be microglia. Since peripherally injected microglia exhibit specific affinity for ischaemic brain lesions and does not exacerbate ischaemic neuronal injury in the present model, we suggest that microglia may have a potential to be used as a piggy-back ride to deliver therapeutic genes and/or drugs for CNS repair following transitory global ischaemic insult.

Brain-derived growth factor and nerve growth factor concentrations are decreased in the substantia nigra in Parkinson's disease

Using highly sensitive sandwich enzyme-linked immunosorbent assays (ELISA), we measured for the first time the concentrations of brain-derived growth factor (BDNF) in the brain (substantia nigra, caudate nucleus, putamen, cerebellum, and frontal cortex) from control and parkinsonian patients. BDNF in the human brain (the order of ng/mg protein) was significantly lower specifically in the nigrostriatal dopamine (DA) regions from parkinsonian patients than in those from control patients. The concentration of nerve growth factor (NGF) was also significantly decreased in the substantia nigra of parkinsonian patients in comparison with that in the controls. Since BDNF and NGF may play important roles in survival and differentiation of neuronal cells, the present data indicate that the lack of neurotrophins, especially BDNF, may be involved in the pathogenesis of PD during progress of neurodegeneration of the nigrostriatal DA neurons.

Comparative analysis of NMR and NIRS measurements of intracellular PO2 in human skeletal muscle

1H NMR has detected both the deoxygenated proximal histidyl NdeltaH signals of myoglobin (deoxyMb) and deoxygenated Hb (deoxyHb) from human gastrocnemius muscle. Exercising the muscle or pressure cuffing the leg to reduce blood flow elicits the appearance of the deoxyMb signal, which increases in intensity as cellular PO2 decreases. The deoxyMb signal is detected with a 45-s time resolution and reaches a steady-state level within 5 min of pressure cuffing. Its desaturation kinetics match those observed in the near-infrared spectroscopy (NIRS) experiments, implying that the NIRS signals are actually monitoring Mb desaturation. That interpretation is consistent with the signal intensity and desaturation of the deoxyHb proximal histidyl NdeltaH signal from the beta-subunit at 73 parts per million. The experimental results establish the feasibility and methodology to observe the deoxyMb and Hb signals in skeletal muscle, help clarify the origin of the NIRS signal, and set a stage for continuing study of O2 regulation in skeletal muscle.

Outgrowth of pseudopodial cables induced by all-trans retinoic acid in micromere-derived cells isolated from sea urchin embryos

Cultured cells derived from micromeres of sea urchin embryos underwent pseudopodial cable growth without spicule rod formation in the presence of all-trans retinoic acid (tRA) or insulin. Pseudopodial cable growth caused by tRA or insulin was inhibited by genistein, a protein tyrosine kinase inhibitor. Phosphorylation of protein tyrosine residue was augmented in the cells treated with tRA or insulin and was inhibited by genistein. Probably, protein tyrosine kinase takes an indispensable part in signal transduction systems for tRA and insulin in these cells. In tRA-treated cells, augmentation of the phosphorylation of protein tyrosine residue was accompanied by an increase in the activity of protein tyrosine kinase and was inhibited by actinomycin D, inhibiting cable growth. Activation of this enzyme in tRA-treated cells probably depends on RNA synthesis. In insulin-treated cells, augmentation of tyrosine residue phosphorylation occurred without any appreciable change in this enzyme's activity and was hardly affected by actinomycin D. Phosphorylation of protein tyrosine residue seems to be activated by the binding of insulin to an insulin receptor. Pseudopodial cable growth in these cells treated with tRA or insulin was inhibited by wortmannin. Phosphatidylinositol 3 kinase probably participates in tRA and insulin signal transduction systems.

Muscle deoxygenation in aerobic and anaerobic exercise

It has been generally accepted that the use of oxygen is a major contributor of ATP synthesis in endurance exercise but not in short sprints. In anaerobic exercise, muscle energy is thought to be initially supported by the PCr-ATP system followed by glycolysis, not through mitochondrial oxidative phosphorylation. However, in real exercise practice, we do not know how much of this notion is true when an athlete approaches his/her maximal capacity of aerobic and anaerobic exercise, such as during a graded VO2max test. This study investigates the use of oxygen in aerobic and anaerobic exercise by monitoring oxygen concentration of the vastus lateralis muscle at maximum intensity using Near Infra-red Spectroscopy (NIRS). We tested 14 sprinters from the University of Penn track team, whose competitive events are high jump, pole vault, 100 m, 200 m, 400 m, and 800 m. The Wingate anaerobic power test was performed on a cycle ergometer with 10% body weight resistance for 30 seconds. To compare oxygenation during aerobic exercise, a steady-state VO2max test with a cycle ergometer was used with 25 watt increments every 2 min. until exhaustion. Results showed that in the Wingate test, total power reached 774 +/- 86 watt, about 3 times greater than that in the VO2max test (270 +/- 43 watt). In the Wingate test, the deoxygenation reached approximately 80% of the established maximum value, while in the VO2max test resulted in approximately 36% deoxygenation. There was no delay in onset of deoxygenation in the Wingate test, while in the VO2max test, deoxygenation did not occur under low intensity work. The results indicate that oxygen was used from the beginning of sprint test, suggesting that the mitochondrial ATP synthesis was triggered after a surprisingly brief exercise duration. One explanation is that prior warm-up (unloaded exercise) was enough to provide the mitochondrial substrates; ADP and Pi to activate oxidative phosphorylation by the type II a and type I myocytes. In addition, transmural pressure created by the muscle contraction reduces blood flow, causing relative hypoxia.

Anti-endothelial cell antibody in preeclampsia: clinical findings and serum cytotoxicity to endothelial cell

BACKGROUND

The role of anti-endothelial cell antibody (AECA) in systemic vasculitis has been reported. One candidate which may disrupt vascular function is AECA. In order to investigate the role of AECA in preeclampsia, the incidence of AECA positive patients, the characteristics of the clinical findings of AECA positive patients and also the cytotoxicity of AECA positive serum for cultured endothelial cells was studied.

METHODS

Serum samples were taken from 57 preeclampsia (including 37 severe cases) and 46 normal pregnant women. The AECA were measured by ELISA using human umbilical vein endothelial cells. The cytotoxicity for cultured endothelial cells by test serum was measured by using 51Cr release assay.

RESULTS

The incidence of IgG and IgM AECA were revealed in 26.3% and 10.5% of preeclampsia respectively. AECA was detected more frequently in severe (29.7%) than in mild preeclampsia (20.0%). In cases with severe proteinuria of greater than 200 mg/dl we detected a significantly higher incidence of AECA than in mild cases (p < 0.04). The incidence of AECA was not significantly increased in cases with severe hypertension or IUGR. The AECA positive sera had greater cytotoxic activity on endothelial cells than AECA negative sera (p < 0.03).

CONCLUSIONS

The appearance of AECA is related to the severity of proteinuria and the cytotoxicity to endothelial cells by AECA positive sera may play a role in causing the endothelial damage in preeclampsia.

Therapeutic effects of dopamine D1/D2 receptor agonists on detrusor hyperreflexia in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-lesioned parkinsonian cynomolgus monkeys

The effects of dopamine receptor agonists on urinary bladder function were evaluated in normal and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned parkinsonian cynomolgus monkeys to investigate the therapeutic efficacy in the treatment of urinary symptoms in Parkinson's disease. Under ketamine anesthesia, cystometrograms exhibited significant reduction in the volume threshold for the micturition reflex in MPTP-lesioned parkinsonian monkeys when compared with those of normal monkeys. The selective dopamine D2 receptor agonist bromocriptine significantly reduced the bladder volume threshold for the micturition reflex by 25 to 30% in both normal and MPTP-lesioned animals. The nonselective D1/D2 receptor agonist pergolide significantly reduced the bladder volume threshold by 22% in normal monkeys, but increased the volume threshold by 50% in MPTP-lesioned parkinsonian monkeys. Another D1/D2 agonist (5R,8R,10R)-6-methyl-8-(1,2,4-triazol-1-ylmethyl) ergoline maleate (BAM-1110) also increased the bladder volume threshold (by 80%) in parkinsonian monkeys without significant effects on the micturition reflex in normal monkeys. The reduction in the volume threshold by bromocriptine in both normal and MPTP-treated groups and by pergolide in normal monkeys was suppressed by pretreatment with the selective D2 antagonist sulpiride, whereas the increment in the volume threshold by pergolide and BAM-1110 in parkinsonian monkeys was antagonized by pretreatment with the selective D1 antagonist SCH 23390, but not by sulpiride. These findings suggest that concurrent activation of D1/D2 receptors, rather than selective stimulation of D2 receptors, might be beneficial for treating urinary symptoms caused by detrusor hyperreflexia in Parkinson's disease.

No association between apolipoprotein E alleles and olivopontocerebellar atrophy

Apolipoprotein E (apo E) epsilon4 is a risk factor for sporadic and late-onset familial Alzheimer's disease, but it is not well known whether the apo E is associated with spinocerebellar degeneration. We studied the frequency of apo E allele in 59 olivopontocerebellar atrophy (OPCA) patients, including 13 pathologically confirmed cases. The distribution of the apo E allele frequency did not differ between OPCA patients and controls. Apo E allele does not influence the development of OPCA.

Mutual link among the approaches to clipping of basilar aneurysms

The pterional approach for basilar aneurysm clipping, has become the most common approach among surgeons, since it was advocated by Yasargil in 1982. However, other approaches aiming at an adequate but less invasive surgery to meet conditions of peripheral blood vessels (including aneurysmal size, direction and perforating arteries and arteriosclerosis) and the direction of clip insertion have also been developed. The approaches will be recommended to be expanded according to situations of the actual intra-operative findings in the future. The mutual link among the approaches to clipping of basilar aneurysms was investigated.

Antiparkinsonian effects of BAM-1110, a novel ergoline derivative, in MPTP-treated cynomolgus monkeys

BAM-1110 [(5R,8R,10R)-6-methyl-8-(1,2,4-triazol-l-ylmethyl) ergoline maleate] is a newly synthesized dopamine agonist that produces little anorexic side effects (nausea and vomiting). The current study examines the effects of BAM-1110 on parkinsonian symptoms in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated monkeys, an animal model of Parkinson's disease. First, a significant antiparkinsonian effect of apomorphine hydrochloride (0.3 mg/kg given subcutaneously) was confirmed in these animals. BAM-1110 (0.1, 0.3, and 1 mg/kg subcutaneously) relieved parkinsonian symptoms in a dose-dependent manner. Significant effects were observed at doses of 0.3 and 1 mg/kg and lasted for at least 3 h. BAM-1110, at a dose of 0.3 mg/kg that produced the submaximal antiparkinsonian effect, did not induce significant abnormal behaviors such as hyperactivity and stereotyped behaviors. Significant stereotyped behaviors were observed at 1 mg/kg of BAM-1110. Apomorphine induced hyperactive and stereotyped behaviors in parallel with its antiparkinsonian effect. BAM-1110 appears to be a potentially useful dopamine agonist to treat Parkinson's disease because of its relatively weak drug-induced hyperactive disturbances and anorexic side effects.

Nationwide multicenter prospective study on the long-term effects of bromocriptine for Parkinson's disease. Final report of a ten-year follow-up

A 10-year nationwide multicenter prospective study on the long-term efficacy of bromocriptine for Parkinson's disease is reported. Six patients remained on bromocriptine monotherapy for 10 years, while 22 patients achieved good disease control with bromocriptine plus levodopa (added during the course of the study). In the 6 patients on bromocriptine alone, the disease remained in Hoehn and Yahr stage I or II for 10 years. In the other 22 patients on bromocriptine plus levodopa therapy, disease progression was very slow for 7-8 years. None of the 6 patients remaining on bromocriptine monotherapy experienced adverse reactions like the wearing-off phenomenon, dyskinesia, or the on-off phenomenon. Among the 22 patients who started levodopa therapy during the course of the study, these adverse reactions to levodopa were infrequent (10, 3, and 3 patients, respectively). Thus, early introduction and long continuation of bromocriptine therapy with restricted concomitant use of levodopa may have led to very slow disease progression and the suppression of adverse reactions. Although the patients who could be maintained long-term on bromocriptine monotherapy might represent a population who have very slowly progressive disease, their adequate disease control and the low incidence of adverse reactions in the patients who later started concomitant levodopa suggest that the unwanted effects of levodopa may be reduced by early and sustained treatment with bromocriptine. Introduction of bromocriptine monotherapy at an early stage of Parkinson's disease or with restricted use of additional levodopa therapy to bromocriptine when necessary may be a useful strategy for achieving adequate and sustained disease control.

Neuroleptic malignant syndrome in parkinsonian patients: risk factors

A syndrome resembling the neuroleptic malignant syndrome (NMS) is known to develop occasionally following interruption of dopaminergic medications in patients with Parkinson's disease. However, NMS can develop even without withdrawal of antiparkinsonian drugs. In parkinsonian patients who continually received dopaminergic medications, the development of NMS occurred exclusively in warm seasons, May to August. The development of NMS could occur at any season in association with the cessation of dopaminergic drugs. A female parkinsonian patient showed two episodes of NMS during the premenstrual period. It is suggested that hot weather or dehydration and aggravation of parkinsonism premenstrually constitute risk factors for the development of NMS, in addition to withdrawal of antiparkinsonian drugs.

Effects of anti-endothelial cell antibody in pre-eclampsia on endothelin-1 release from cultured endothelial cells

In order to investigate the pathophysiological significance of anti-endothelial cell antibody (AECA) in pre-eclampsia, the effects of AECA on endothelin-1 (ET-1) and prostaglandin I2 (PGI2) release from cultured human umbilical vein endothelial cells (HUVEC) was evaluated. Serum samples were taken from 85 pre-eclamptic and 20 normal pregnant women. Anti-endothelial cell antibody was measured by ELISA using HUVEC. The release of ET-1 and 6-keto PGF1-alpha, a stable metabolite of PGI2, from HUVEC were evaluated after incubation with IgG-AECA-positive sera and IgG isolated from AECA-positive sera. The incidence of IgG- and IgM-AECA was 24.7 and 8.2%, respectively. The release of ET-1, in the medium containing IgG-AECA-positive sera was significantly greater than in the medium containing IgG-AECA-negative sera. There was significant correlation between the levels of IgG-AECA and the release of ET-1 from endothelial cells. The ET-1 release by IgG isolated from AECA-positive sera was greater than that from AECA-negative sera. However, the release of 6-keto PGF1-alpha by AECA-positive sera was not significantly different from that of AECA-negative sera. It is concluded that IgG-AECA in pre-eclampsia increases ET-1 release from endothelial cells and that AECA may affect local vascular function in this disorder.

Muscle architecture and function in humans

The present study focused on architectural factors which are considered to influence the linkage of muscle fiber and joint actions. By means of real-time ultrasonography we can observe clearly and noninvasively in vivo the movement of fascicle and aponeurosis in human muscle and measure directly the changes in pennation angle and length of fascicle during muscle contraction. During dorsi and plantar flexion without load the movement of tendinous tissue in human tibialis anterior muscle (TA) appeared to synchronize with the displacement of the ankle joint, indicating that the muscle tendon complexes are stiff relative to the applied force, which is fairly small in the case of foot shaking motion. On the other hand, when the ankle joint was fixed and the TA contracted 'statically' the ultrasonic echo from deep aponeurosis in the TA was observed to move proximally, indicating the elastic component (i.e. mainly tendinous tissue) was stretched significantly by the contraction force of muscle. In the case of the kneejoint, a length of fascicle in vastus lateralis decreased by 18% with the extension of the knee passively from a 100 degrees flexed position. When the knee extensors contracted 'statically' the fascicle length decreased at every joint angles and its magnitude was greater (30%) when the knee was closer to full extension than (5%) at the flexed positions. The present results clearly show that the architecture of actively contracting muscle fibers differ considerably than that which occurs when movement is passively induced. The use of cadaver data in the study of architecture and modeling of muscle functions would result in inaccurate, and in some cases even erroneous results.

Differential therapeutic effects of dopamine D1 and D2 agonists in MPTP-induced parkinsonian monkeys: clinical implications

L-DOPA, the precursor of dopamine, remains most effective in the treatment of patients with Parkinson's disease, but prolonged L-DOPA treatment often produces adverse effects, including dyskinesia and psychosis. Dopamine receptors can be divided into two major subtypes, D1 and D2. Might both subtypes of the dopamine receptor be equally relevant to amelioration of parkinsonian symptoms and responsible for the adverse side effects? To address this question, the effects of D1 or D2 receptor agonists alone and in joint administration were examined in MPTP-induced parkinsonian monkeys. The parkinsonian symptoms, such as tremor, bradykinesia and rigidity, and the adverse side effects, such as hyperactivity and aggressiveness, were evaluated independently using different behavioral criteria. The results showed that antiparkinsonian effects can be exerted either by the D1 agonist (SKF 82958) alone or by the D2 agonist (quinpirole) alone, whereas hyperactivity and aggressiveness manifested by dopamine agonists require coactivation of the D1 and D2 receptors. Thus, the antiparkinsonian effect can be dissociated from the adverse effect by therapeutic strategy. It is implied that imbalances in activation of the D1 and D2 receptors may provide a favorable approach for long-term treatment of parkinsonian patients with dopamine drugs.

Nine-year follow-up study of bromocriptine monotherapy for Parkinson's disease

A 9-year nationwide study of bromocriptine monotherapy and combination therapy with bromocriptine and levodopa in Parkinson's disease is reported. Eleven patients were on bromocriptine monotherapy, 35 patients were on combined treatment of bromocriptine and levodopa for a certain time during a 9-year period. Maintenance doses of bromocriptine at the end of the 9th year in the two groups were 11.1 mg/day in the monotherapy and 12.7 mg/day in the combination therapy group with levodopa. Changes in Hoehn and Yahr's grading between the time of trial start and the end of 108 months' treatment revealed that 5 of 11 cases in the monotherapy group remained in the same stages, the other 2 cases improved in condition from stage II to I, and another 4 deteriorated compared with pretreatment grade. On the other hand, 20 of 35 cases in the combination-therapy group reached more advanced stages, 3 patients moving to stage V. Four of them, however, improved, and 11 did not change at the end of 9 years of treatment. Although it is difficult to prove the neuroprotective effect of a dopamine receptor agonist, our long-term nation-wide collaborative studies will help us to answer the question of how bromocriptine works in pharmacokinetic aspects.

Effects of 20 days of bed rest on physiological cross-sectional area of human thigh and leg muscles evaluated by magnetic resonance imaging

The present study was to investigate the effects of 20 days of bed rest on morphological characteristics of lower limb skeletal muscles. Ten sedentary volunteers (5 males and 5 females) were participating in this study. Magnetic resonance imaging techniques were used to measure the physiological cross-sectional areas (PCSAs) of the major muscles and muscle groups of the lower limb. Consecutive images were taken from the right thigh and leg of subjects, and muscle volumes (MV), muscle length, and fiber length were calculated. PCSA of each muscle was determined as MV times the cosine of the angle of fiber pennation divided by fiber length. PCSA of knee extensor and flexor muscles were significant reduced during and after bed rest. MV and PCSA of individual muscles in the knee extensors decreased by -5.1 % to -8.0%. In knee flexors, MV and PCSA in biceps femoris (long head), semitendinosus, semimembranosus, and sartorius decreased during and after bed rest. MV and PCSA in medial and lateralis [correction of andateralis] gastrocnemius, and soleus were remarkably reduced by -9.4 to -10.3% after bed rest. The results suggest that there is a great variability of muscle atrophy in the lower limb muscle groups or individual muscle after bed rest and that the plantar flexors primarily affected.

[Treatment of Parkinson's disease with multiple drugs]

All major symptoms of Parkinson's disease, i.e., rigidity, tremor, hypokinesia and postural instability are induced by an impaired dopaminergic neurotransmission in the nigro-striatal pathway. Levodopa pioneered the symptomatic therapy of Parkinson's disease. While it is effective on the motor symptoms, long-term levodopa therapy often results in dyskinesia, motor fluctuations and psychosis. Coadministration of levodopa and dopamine agonists, bromocriptine and pergolide, decreases these adverse side effects. Anticholinergics and amantadine are often effective as adjuvant drugs for the early stage of patients with Parkinson's disease. Furthermore, L-threo-DOPS, nor-adrenergic precursor drug, is sometimes effective for the advanced stage of Parkinson's disease. Thus coadministration of multiple antiparkinsonian drugs, rather than single therapy of levodopa, is useful for the long-term treatment of Parkinson's disease.

Effects of tolcapone, a catechol-O-methyltransferase inhibitor, on motor symptoms and pharmacokinetics of levodopa in patients with Parkinson's disease

The effects of tolcapone, a catechol-O-methyltransferase inhibitor, on the bioavailability and efficacy of levodopa were evaluated in 12 patients with Parkinson's disease (PD), 8 of whom showed signs of daily motor fluctuations (wearing-off phenomenon). Motor disabilities were assessed in 12 patients at 7 time points before and after the chronic administration of tolcapone using the Unified Parkinson's Disease Rating Scale (UPDRS). The UPDRS score was improved at all points of determination. Eight patients with wearing-off phenomenon on levodopa showed symptomatic improvement on the combination. The area under the curve (AUC) for levodopa increased by 34% (p = 0.0059) after the administration of tolcapone. The elimination half-life (T1/2) of levodopa was significantly prolonged by 81% (p = 0.0001) after the treatment. The AUC of 3-O-methyldopa, a metabolite of levodopa, was decreased by 79% (p = 0.0001) and the Cmax (maximum concentration) was also decreased by 80%d after the administration (p = 0.0001) of tolcapone. The combination of tolcapone and levodopa was well tolerated. Our findings suggest that tolcapone improves the pharmacokinetics of levodopa in plasma and motor symptoms of fluctuating PD patients. It is suggested that tolcapone may be useful drug adjunct to levodopa in treating patients with PD with wearing-off phenomena.

Tendinous movement of a human muscle during voluntary contractions determined by real-time ultrasonography

The degree of shortening or lengthening of muscles during joint actions has not been clarified in humans, although such information is essential in understanding human muscle functions. In this study, the tendinous movement of a muscle was determined by real-time ultrasonography during voluntary contractions. The tibialis anterior muscle (TA) was tested in five healthy men who performed dorsi- and plantar flexion movements (shortening and lengthening of TA) at two frequencies (0.1 and 1.5 Hz). The insertion point (eta) of fascicles onto the aponeurosis was clearly visualized on the ultrasonogram, and its position relative to a fixed marker moved proximally and distally according to dorsi- and plantar flexion of ankle joint. The movement of eta occurred in phase with the angular change of ankle joint, giving high correlations (r = 0.93 to 0.97) between the displacement of eta and the angle. The displacement of eta for one radian of joint angle change, 46.5 +/- 1.7 (SD) mm, was comparable to the reported moment arm of TA. The present method has many potential applications in the field of muscle physiology and biomechanics in humans.

Influence of two different modes of resistance training in female subjects

In resistance training, it has been empirically accepted that muscle hypertrophy is developed by low intensity and high volume training, while muscle strength and power are developed by high intensity and low volume training. The purpose of the present study was to investigate the influence of two different modes of resistance training on isokinetic strength and muscle cross-sectional area (CSA) in females. Eleven females, who had no experience in resistance training, participated in this study and were randomly divided into two groups. The former consisted of 4-5 sets of 15-20 RM (repetition maximum) with sufficient rest between sets (Group H), while the latter consisted of 8-9 sets of 4-6R M with 90 s of rest between sets (Group S). The former was assumed to be appropriate for muscle hypertrophy and the latter muscle strength, respectively. All subjects completed isotonic knee extension exercise three times a week for 8 weeks. Measurements were made on quadriceps muscle cross-sectional area (CSA) and isokinetic torques at 0, 60, 180, and approximately 300 degrees before training, at the fifth week and the end of training period. Muscle CSA was defined as the sum of CSA measured at 30, 50 and 70% of femur length. After training, muscle CSA had significantly increased in both groups: 3.3 +/- 0.7% (p < .05) for group H and 3.6 +/- 1.1% (p < .05) for group S, respectively. While the changes in isokinetic torque were 43.4 +/- 47.5% (p < .05) for group H and 27.4 +/- 31.3% (p < .05) for group S, respectively. In both groups the percentage changes of the isokinetic strength were significantly higher than those of the CSA. No significant difference in these variables were found between the two groups. These results suggest that during the early phase of resistance training two different modes of resistance training may have similar effects on muscle CSA and isokinetic strength in untrained females.

Eight-year follow-up study of bromocriptine monotherapy for Parkinson's disease

An 8-year nationwide study of bromocriptine monotherapy and combination therapy with bromocriptine and levodopa in Parkinson's disease is reported. Fifteen patients were on bromocriptine monotherapy, and 44 patients on bromocriptine combined with levodopa for a certain time during an 8-year period. By judging from Hoehn and Yahr's grading, 4 of the 15 patients in the monotherapy group were in a better condition than before treatment, while 7 cases remained in the same grading, and only 4 showed deterioration. On the other hand, 26 of 44 patients on combination therapy showed more advanced grading at the end of 8 years compared to the stage at the onset of the trial. Maintenance doses of bromocriptine in the two groups were 12-13 mg per day, and levodopa doses were kept at a relatively low level (310-370 mg per day) during this study period. Whether dopamine receptor agonists have neuroprotective effect or not is extremely difficult to prove in human subjects, but this type of long-term follow-up study might give some clues as to these important questions.

Combined effects of cabergoline and L-dopa on parkinsonism in MPTP-treated cynomolgus monkeys

The behavioral effects of L-dopa or cabergoline alone were compared with those of the joint administration of the two drugs in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned parkinsonian cynomolgus monkeys with attention to the induction of hyperactivity and dyskinesia. Cabergoline alone at 0.2 mg/kg or less improved in a dose-dependent fashion the parkinsonism without inducing hyperactivity and dyskinesia following a single subcutaneous injection. L-dopa alone improved the parkinsonism, but induced hyperactivity and dyskinesia, depending on the dose applied. Doses required for 50% amelioration by L-dopa and cabergoline were 10 and 0.038 mg/kg, s.c., respectively. With low doses (50%-amelioration doses), cabergoline or L-dopa alone improved the parkinsonism without induction of hyperactivity and dyskinesia, but the duration of action was brief. Cabergoline in combination with L-dopa was highly effective in improving motor disability without induction of hyperactivity and dyskinesia. Moreover, the duration of action was more prolonged with the coadministration than with the single administration of each drug. These findings suggest that the combined therapy with low doses of L-dopa and cabergoline is beneficial for treating patients with advanced Parkinson's disease.

Glycemic control, growth and complications in children with insulin-dependent diabetes mellitus--a study of children enrolled in a Summer camp program for diabetics in Kinki district, Japan

The influence of glycemic control on growth and on the development of complications in diabetic children was studied. The subjects of the study were 107 children with insulin-dependent diabetes mellitus (IDDM), who were enrolled in a Summer camp program for diabetic children in Kinki District, Japan from 1972 to 1990, and who had at least three determinations of HbA1 during the observation period. Many of the children had high mean levels of HbA1, regardless of age. The height and weight were below the standards for the respective ages in many children, indicating the retardation of growth. However, S.D. scores for height and weight and other physical indices were not related to the mean levels of HbA1. By contrast, the prevalence of diabetic retinopathy was related to an elevated mean level of HbA1, but that of albuminuria was not. Serum cholesterol levels were higher in children with higher mean levels of HbA1, but serum triglycerides appeared not to be related to glycemic control. The incidence of retinopathy during the observation period closely related to the degree of the mean levels of HbA1, but that of albuminuria did not.

Somatic mosaicism of CAG repeat in dentatorubral-pallidoluysian atrophy (DRPLA)

An unstable expansion of CAG repeat in the coding region of the DRPLA gene on chromosome 12p is the mutation specific for hereditary dentatorubral-pallidoluysian atrophy (DRPLA). We studied the CAG expansion in brain and other tissues from six unrelated DRPLA patients. The CAG repeat lengths showed distinct differences between tissues. The sizes of the CAG expansion in various regions of the brain except the cerebellum were generally larger by several repeats than in other peripheral tissues. Brain samples showed greater variation of the expansion compared with other tissues, but neither the size of the CAG expansion nor the degree of CAG repeat variation parallels the detailed findings of neuropathological involvement. We conclude that somatic instabilities of the CAG repeat cause tissue variability of the CAG repeat size in DRPLA but other region or cell type-specific factors would be involved to explain the selectivity of cell damage in DRPLA.

Combination treatment of the partial D2 agonist terguride with the D1 agonist SKF 82958 in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-lesioned parkinsonian cynomolgus monkeys

The optimal combination of a dopamine D2 agonist and a D1 agonist was evaluated for symptomatic treatment of Parkinson's disease. Behavioral effects of combination treatment of the full D2 agonist quinpirole or the partial D2 agonist terguride with the full D1 agonist SKF 82958 [(I) 6-Chloro-7, 8-dihydroxy-3-allyl-1-phenyl-2, 3, 4, 5-tetra-hydro-1H-3-benzazepine] were investigated in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned parkinsonian cynomolgus monkeys with attention to the induction of hyperactivity such as irritability, excitability and aggressiveness and of dyskinesias such as licking of paws, chewing and biting. Both quinpirole and SKF 82958 alone improved the parkinsonism with a slight induction of the hyperactivity and dyskinesias. Terguride also improved the parkinsonism but did not induce the hyperactivity and dyskinesias. Combination treatment of quinpirole with SKF 82958 not only showed a tendency to augment the antiparkinsonian effects but also induced the marked hyperactivity and dyskinesias. On the other hand, combination treatment of terguride with SKF 82958 also augmented the antiparkinsonian effects but did not induce any hyperactivity and dyskinesias. These findings suggest that combination therapy with a partial D2 agonist and a full D1 agonist or monotherapy with a dopamine agonist that has both partial D2 and full D1 agonist properties might be beneficial for treating motor dysfunction in Parkinson's disease without inducing dopaminergic side effects.

Behavioral involvement of central dopamine D1 and D2 receptors in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned parkinsonian cynomolgus monkeys

To clarify the roles of dopamine D1 and D2 receptors in behavioral symptoms of Parkinson's disease, antiparkinsonian effects of various dopamine agonists in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned parkinsonian monkeys were investigated with regard to induction of hyperactivity such as excitability, irritability and aggressiveness. The non-selective dopamine agonist apomorphine ameliorated the parkinsonism, but induced marked hyperactivity dose-dependently. Pretreatment with either the dopamine D1 antagonist SCH 23390 or the dopamine D2 antagonist sulpiride markedly suppressed the apomorphine-induced hyperactivity with slight attenuation of the antiparkinsonian effects. Both the dopamine D2-receptor agonist quinpirole and the dopamine D1-receptor agonist SKF 82958 ameliorated the parkinsonism in a dose-dependent manner with a slight induction of hyperactivity. Combination treatment of a threshold dose of quinpirole with that of SKF 82958 augmented the antiparkinsonian effects without a marked induction of hyperactivity. However, the combination treatment at higher doses induced marked hyperactivity accompanied by augmented antiparkinsonian effects. These results suggest that stimulation of either central dopamine D1 or D2 receptors is requisite for the antiparkinsonian effects and concurrent strong stimulation of both central dopamine D1 and D2 receptors causes marked hyperactivity which may be predictive of dopaminergic psychiatric side effects.

Differential effects of three dopamine receptor agonists in MPTP-treated monkeys

The behavioral effects of cabergoline, pergolide and bromocriptine were investigated in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned parkinsonian cynomolgus monkeys with attention to the induction of hyperactivity, as evidenced by irritability, excitability and aggressiveness. All three drugs improved the parkinsonism in a dose-dependent fashion following a single injection. Among the three dopamine (DA) receptor agonists used, the antiparkinsonian effect of pergolide was the strongest and had an immediate effect, while cabergoline showed the longest duration of the antiparkinsonian effect and was least potent in inducing hyperactivity.

Muscle metabolism during exercise using phosphorus-31 nuclear magnetic resonance spectroscopy in adolescents

Very little has been reported on muscle energetics during exercise in adolescents. This is attributable to the difficulty of subjecting children to muscle biopsy. The purpose of this study was to investigate the characteristics of muscle metabolism during exercise in vivo in adolescents by comparing firstly, with adults and secondly, the differences resulting from physical activity using phosphorus-31 nuclear magnetic resonance (31P NMR) spectroscopy. The subjects were boys aged 12 to 15 years, comprising 21 trained boys and 23 control boys, and 6 adults controls. The ratio of phosphocreatine (PCr):(PCr + P(i)), where P(i) is inorganic phosphate intracellular pH at exhaustion and the time constant of PCr during recovery were measured in all the subjects using 31P NMR. Both groups of children showed higher values of PCr:(PCr + P(i)) and intracellular pH at exhaustion than did the adult control group (P < 0.01 or P < 0.05). However, no significant differences were found between the trained boys and the control boys with respect to PCr:(PCr + P(i)) and intracellular pH at exhaustion. On the other hand, we found the same values for PCr time constant in all groups. This result suggested no differences of the muscle oxidative capacity between children and adults. We concluded that the adolescents, aged 12 to 15 years in both the trained and control groups, had less glycolytic ability during exercise than the adults.

Measurement of muscle fibre displacement during contraction by real-time ultrasonography in humans

The contact point (P) made by both the echoes of the aponeurosis and from interspaces among fascicles of the tibialis anterior muscle was detected by real-time ultrasound scanning in 12 adults. Movement in the location of P was observed during muscle contraction and its displacement was related to changes in ankle joint angles (r = 0.81, P < 0.01), i.e., P shifted proximally when the ankle joint was dorsiflexed. There was also a significant positive correlation between the degree of dorsiflexion and the velocity related to the change in location of P (r = 0.84, P < 0.01). Ultrasound measurements of the displacement and the velocity of P were reproducible as there was no variation noticed among measurements on different days. It is suggested from these results that the displacement of P reflected changes in muscle length during contraction and that this amount of change corresponded to changes in joint angles.

In vivo human myocardial metabolism during aerobic exercise by phosphorus-31 nuclear magnetic resonance spectroscopy

A few studies have been made in vivo on human myocardial energy metabolism. Hence, no discussion has taken place on metabolism during exercise or of training effects on metabolism. We examined human myocardial energy metabolism at rest and during exercise, and also training effects on the metabolism by phosphorus-31 nuclear magnetic resonance (31P NMR)-spectroscopy. Six sedentary male students (Cont) and six male long distance runners (Tr) were the subjects. Energy metabolism data were obtained from myocardium during rest and exercise by the region selection method using 31P NMR. Rotation of the legs while riding a bicycle, which was fitted with an ergometer we had made ourselves for NMR, imposed given exercise intensities. The heart rate was measured in a stationary phase during exercise. Although the heart rate at rest in the Tr group was significantly lower [Tr, 52.5 (SD 3.1) beat.min-1; Cont, 67.1 (SD 2.9) beat.min-1], no significant difference was observed in myocardial energy metabolism using the 31P NMR method [Tr, phosphocreatine/beta-adenosine 5'-triphosphate (PCr/beta-ATP); 1.51 (SD 0.02); Cont, 1.51 (SD 0.01)]. When NMR measurements were investigated at two different intensities of exercise, heart rates in the Cont group were significantly higher by about 20 beat.min-1 than those in the Tr group at both exercise intensities, while no difference in energy metabolism was observed between the groups or between rest and exercise [Tr, 75.9 (SD 3.6), 88.3 (SD 3.7) beat.min-1; PCr/beta-ATP 1.51 (SD 0.03), 1.51 (SD 0.03); Cont, 95.9 (SD 2.4), 115.1 (SD 3.5) beat.min-1, PCr/beta-ATP 1.51 (SD 0.01), 1.51 (SD 0.04)].(ABSTRACT TRUNCATED AT 250 WORDS)

Muscle energetics in short-term training during hypoxia in elite combination skiers

Four well-trained combination skiers were studied through pre- and post-training for the effects of short-term intermittent training during hypoxia on muscle energetics during submaximal exercise as measured by Phosphorus-31 nuclear magnetic resonance and maximal aerobic power (VO2max). The hypoxia and training in the cold was conducted in a hypobaric chamber and comprised 60-min aerobic exercise (at an intensity equivalent to the blood lactate threshold), using a cycle ergometer or a treadmill twice a day for 4, consecutive days at 5 degrees C, in conditions equivalent to an altitude of 2000 m (593 mm Hg). No change in VO2max was observed over the training period, while in the muscle energetics during submaximal exercise, the values of phosphocreatine/(phosphocreatine+inorganic phosphate) and intracellular pH were found to be significantly increased by training during hypoxia. During recovery, the time constant of phosphocreatine was found to have been significantly reduced [pre, 27.9 (SD 6.7) s; post, 22.5 (SD 4.7) s, P < 0.01]. The observed inhibition of phosphocreatine as well as that of intracellular pH changes after training during hypoxia and quicker recovery of phosphocreatine in submaximal exercise tests, may indicate improved oxidative capacity (i.e. a high adenosine 5'-triphosphate formation rate) despite the short-term hypoxia training.

Pharmacological characterization of the novel anxiolytic beta-carboline abecarnil in rodents and primates

beta-Carboline abecarnil was behaviorally and biochemically characterized as a new anxiolytic agent in rodents and primates in comparison with the benzodiazepine (BZ) anxiolytics. Oral treatment with abecarnil (0.5-10 mg/kg) showed a potent anticonflict activity in the water-lick test in rats. The minimal effective dose was lower than those of BZ anxiolytics, such as etizolam, diazepam, clotiazepam and tofisopam. Abecarnil also showed taming effects to suppress fighting and aggressive behaviors in mice and monkeys with little sedative and ataxic effects, in contrast to the BZ anxiolytics producing marked sedative and ataxic effects. Furthermore, abecarnil suppressed both the sedative and ataxic effects induced by diazepam. Abecarnil bound to rat cerebellar BZ1 receptors (Ki = 0.24 nM) with higher affinity than to rat spinal cord BZ2 receptors (Ki = 1.3 nM), whereas BZ derivatives bound to both the receptors with a low and equal affinity. GABA-ratios of abecarnil were 1.9 for the BZ1 receptors and 2.8 for the BZ2 receptors, and they were smaller than those of diazepam and flunitrazepam. Thus, in contrast to the BZ derivatives, abecarnil may act as a selective partial agonist at central BZ1 receptors, resulting in its potent anticonflict and taming effects with little sedative and ataxic effects.

Changes in magnetic resonance images in human skeletal muscle after eccentric exercise

To investigate the time-course of changes in transverse relaxation time (T2) and cross-sectional area (CSA) of the quadriceps muscle after a single session of eccentric exercise, magnetic resonance imaging was performed on six healthy male volunteers before and at 0, 7, 15, 20, 30 and 60 min and 12, 24, 36, 48, 72 and 168 h after exercise. Although there was almost no muscle soreness immediately after exercise, it started to increase 1 day after, peaking 1-2 days after the exercise (P < 0.01). Immediately after exercise, T2 increased significantly in the rectus femoris, vastus lateralis and intermedius muscles (P < 0.05) and decreased quickly continuing until 60 min after exercise. At and after the 12th h, a significant increase was perceived again in the T2 values of the vastus lateralis and intermedius muscles (P < 0.01) [maximum 9.3 (SEM 2.8)% and 10.9 (SEM 2.2)%, respectively]. The maximal values were exhibited at 24-36 h after exercise. In contrast, the rectus femoris muscle showed no delayed-stage increase. Also, in CSA, an increase after 12 h was observed in addition to the one immediately after exercise in the vastus lateralis, intermedius and medialis and quadriceps muscles as a whole (P < 0.01), reaching the maximal values at 12-24 h after exercise. The plasma creatine kinase activity remained unchanged up to 24 h after and then increased significantly 48 h after exercise (P < 0.05). Beginning 12 h after exercise, the subjects whose T2 and CSA increased less than the others displayed a faster decrease in muscle soreness.(ABSTRACT TRUNCATED AT 250 WORDS)

Dilemma in the treatment of Parkinson's disease with L-dopa

L-Dopa pioneered the symptomatic therapy of Parkinson's disease. While this treatment proved effective in the treatment of parkinsonian akinesia, rigidity and tremor, prolonged L-dopa treatment was often noted to result in dyskinesia, psychosis and 'on-off' phenomena. This increasing disability of L-Dopa-treated parkinsonian patients, however, is not correlated with the duration of L-dopa treatment. Mortality due to Parkinson's disease has decreased significantly after the introduction of L-dopa treatment. The development of D1-selective dopamine agonists and the introduction of neuroprotective rather than symptomatic therapy are required for treating Parkinson's disease.

Seven-year follow-up study of bromocriptine therapy for Parkinson's disease

A 7-year nationwide study of bromocriptine monotherapy and combination therapy with bromocriptine and levodopa in Parkinson's disease is reported. Of 22 patients who had been on bromocriptine monotherapy for 7 years (group B), 16 remained improved or remained in the same stages of Hoehn and Yahr, and no wearing-off phenomenon or dyskinesia was observed. In another 56 patients who were started on bromocriptine alone, but in whom combination therapy with levodopa was instituted at some time in the 7 years (group BL), disease progressed faster than in group B. A wearing-off phenomenon and dyskinesia occurred in 34% and 5.4% of the patients, respectively. These manifestations appeared only after initiation of levodopa. The favorable course of group B suggests possible neuroprotective effects of bromocriptine or may be due to the inevitable selection of patients who had a favorable course originally.