Analysis of nutritive sucking function in very low and extremely low birthweight infants in Japan: A pilot study

Aim: The purpose of the present study was to investigate the differences in nutritive sucking patterns between very low, extremely low birth‐weight infants (LBWI) and full‐term infants (FTI) and to examine the change in those sucking patterns within 5 months after birth. Methods: Sucking patterns of eight LBWI and seven FTI were compared. In addition, sucking patterns were measured in four of the LBWI and seven of the FTI until 5 months of age to determine change in sucking wave patterns over time. Results: During the first month after birth, there was a significant difference in the sucking wave between the LBWI and FTI. The sucking cycle time was significantly shorter and the intensity of the sucking pressure was significantly smaller in the LBWI than that in the FTI. By 5 months, significant correlations were noted between the actual age or the modified age and the sucking pressure in both LBWI and FTI. Conclusions: The findings suggest that the weakness of oral muscular function and less sucking skill can bring about the weakness of intensity of sucking pressure, decreased time of the sucking stage in a sucking cycle, and unstable intensity of sucking pressure and time of the sucking stage in LBWI infants, causing low efficiency of milk intake and smaller amounts of milk swallowing during each sucking period as they obstructs the development of oral muscular function itself. These problems last for a longer period of time in LBWI than in FTI, leading to a deficit in the development of masticatory function in LBWI. The results of the current pilot study will serve as a foundation to investigate the development of masticatory function in LBWI as they grow into early childhood.     

Increase of oxidized/total coenzyme Q-10 ratio in cerebrospinal fluid in patients with Parkinson's disease.

The concentrations of oxidized coenzyme Q-10 (CoQ-10) and reduced CoQ-10 in the cerebrospinal fluid (CSF) of patients with Parkinson's disease (PD) was examined in order to determine whether the balance in oxidized and reduced CoQ-10 is related to the pathogenesis of PD. The percentage of oxidized/total CoQ-10 (%CoQ-10) in the CSF was significantly higher in the untreated PD group (80.3+/-17.9%) compared to the normal control group (68.2+/-20.4%) (p<0.05). The %CoQ-10 in the CSF of PD patients showed significant negative correlation with the duration of illness. These findings in living patients provide in vivo evidence for a possible role for %CoQ-10 in the pathogenesis in the early stages of PD development.     

Evaluation of blood flow patterns of true and false lumens in dissecting aneurysms using MR phase-contrast techniques

The magnetic resonance phase-contrast technique for the measurement of flow velocity and volume in true and false lumens was studied in six patients with chronic dissecting aneurysms. Phase-contrast images were obtained at a level perpendicular to the dissecting aneurysms of the descending aorta. As the maximum diameter of aneurysms increased, the ratio of the cross-sectional area of the false to the true lumen increased and the peak average velocity in the true lumen during systole was decreased. This technique proved invaluable for determining prognosis and operability for this condition.     

Local muscimol disinhibits mesolimbic dopaminergic activity as examined by brain microdialysis and Fos immunohistochemistry

Infusion of muscimol (5×10⁻⁵ M, 60 min) into the nucleus accumbens (NAC) through a dialysis membrane caused a significant increase in extracellular dopamine (DA) and its metabolite, 3,4-dihydroxyphenylacetic acid (DOPAC). Fos-like immunoreactivity induced by intra-NAC infusion of muscimol was seen ipsilaterally in many accumbofugal target areas, but no Fos-positive neurons were seen in the vicinity of the dialysis membrane in the NAC. Sequential staining of Fos and tyrosine hydroxylase (TH) immunoreactivities revealed that a portion of A10 dopaminergic neurons were double-labelled. These results suggest that muscimol in the NAC disinhibits mesolimbic DA neuronal activity possibly through activity of the accumbofugal GABA neuron system.     

Arterial embolization as preoperative treatment for pulmonary aspergillosis with hemoptysis

Pulmonary aspergillosis associated with old tuberculosis is generally resistant to treatment. Thus, if patients are treated only with conservative therapy, their condition continues to deteriorate due to repetitive hemoptysis, and may even become critical. Surgical treatment is required for these patients; however, it is extremely difficult to resect the lesion due to severe adhesions to the chest wall and vascular proliferation surrounding the lesion. We performed preoperative arterial embolization, achieving good results in three patients with hemoptysis caused by pulmonary aspergillosis. The feeding arteries were embolized using microcoils and/or gelatin sponges, and a lobectomy was safely carried out in all patients. We concluded that preoperative arterial embolization is a safe and effective technique to prevent massive hemorrhage occurring at the time of surgery. This work was presented at the 11th Annual Meeting of the Japanese Association for Chest Surgery, held in Kyoto, Japan, May 13–14, 1994     

Validity of Electrode Placement at Fpz to Detect Alpha Wave

Abstract: The possibility on placing electrodes at Fpz-A₂ instead of C₃-A₂ was investigated to obtain a more stable configuration avoiding obstruction by the hair. Our original system of alpha wave detection by a microcomputer was used, and a total of 22 all-night hypnograms of five healthy young students waa recorded. Pearson's moment correlation coefficients of alpha wave % between the two positions were 0.780–0.948. Except for one subject, alpha wave % taken at Fpz-A₂ tended to be 3–5% lower than that at C₃-A₂. The above analysis indicates that using EEG electrode position of Fpz-A₂ is valid and useful as a stable electrode configuration for a long-time monitoring.     

EFFECTS OF SARAFOTOXIN S6c ON RENAL HAEMODYNAMICS AND URINE FORMATION IN ANAESTHETIZED DOGS

1. The effects of sarafotoxin S6c (S6c), a selective endothelin ETB receptor agonist, on renal haemodynamics and urine formation were examined in anaesthetized dogs. 2. Intrarenal arterial infusion of S6c at a rate of 1 or 5 ng/kg per min produced a transient increase in renal blood flow (RBF), with no change in systemic blood pressure and heart rate; RBF then decreased gradually to below the basal value. There were significant and dose-dependent increases in urine flow and free water clearance and decreases in urine osmolality during S6c infusion, whereas urinary excretion of sodium and glomerular filtration rate (GFR) remained unchanged. Simultaneously, S6c administration elicited a marked increase in urinary excretion of nitric oxide (NO) metabolites, N0₂^? and N0₃^? (UNO*V). 3. In dogs simultaneously administered S6c (5 ng/kg per min) and iV^G-nitro-L-arginine (NOARG; 40 (jig/kg per min), a NO synthase inhibitor, the renal vasodilator effect of S6c was abolished and marked reductions in RBF and GFR were observed. The S6c-induced diuretic action was not affected by NOARG. In the presence of NOARG, there was a small amount of UNO_xV at the basal level and the administration of S6c did not increase UNOxV. 4. These results suggest that an intrarenal arterial infusion of S6c enhances the production of NO in the kidney and that this enhancement contributes to the peptide-induced renal vasodilation. In contrast, it is unlikely that S6c-induced water diuresis is related to NO production stimulated by this peptide.     

Experimental study of spinal cord compression by epidural tumors using electron probe X-ray microanalysis and confocal laser scanning microscopy

Changes in the nerve fibers of the spinal cord were studied in rat experimental epidural tumor models. Light microscopy showed demyelinization in all with rats paraparesis and paraplegia. Cross-sectional views of nerve fibers stained with 3,3dipentyloxacarbo-cyanine iodide, obtained by confocal laser scanning microscopy, showed distorted, shrunken fibers with a low fluorescence intensity. Changes in the electrolyte contents of nerve fibers were studied by electron probe X-ray microanalysis. The K concentration in axons and the myelin sheath was increased in the paraparesis group, but was decreased in the paraplegia group. These findings suggest that, in the paraparesis group, compression of the spinal cord damaged cell membrane channels, which subsequently caused an increase in intracellular K, a decline in the action potential, and low-intensity fluorescence of nerve fibers. On the other hand, in the paraplegia group, destruction of cell membranes caused a decrease in intracellular K until it approached the extracellular level. This reduced both the action potential and the fluorescence intensity. As Ca and Mg concentrations in both axons and the myelin sheath increased in relation to the severity of neurologic damage, it appears that these electrolytes may also play an important role in damage to nerve fibers.     

Pharmacokinetics of amitriptyline and its demethylated metabolite in serum and specific brain regions of rats after acute and chronic administration of amitriptyline

The concentrations of amitriptyline (AMT) and its demethylated metabolite nortriptyline (NRT) in the serum and in specific brain regions were determined periodically after acute or chronic administration of 20 mg/kg of AMT in rats. Both AMT and NRT declined from the serum in a biexponential manner and were eliminated monoexponentially from the brain regions, with no significant difference in elimination among the eight brain regions examined. In the brain, both AMT and NRT were unevenly distributed after chronic administration, whereas an even distribution was observed after acute administration. The AUCbrain:AUCserum ratio of AMT was higher than that of NRT, indicating greater transport of AMT into the brain regions. The AUCAMT value in the serum increased 1.6 times after chronic administration, whereas no significant changes were observed in the brain regions. The AUCNRT values increased 9.0 times in the serum and 6.8 times in the brain, with the increase in the serum being greater. These results suggest inhibited distribution of the drugs into the tissues, including the brain regions, and enhanced metabolism of AMT.