The adrenergic modulation of firings of respiratory rhythm-generating neurons in medulla-spinal cord preparation from newborn rat

We analysed the modulation of respiratory neurons by adrenaline or noradrenaline (NA) in a newborn rat brainstem-spinal cord preparation. Adrenaline or NA caused a dose-dependent depression of the respiratory rhythm and induced C4 spinal tonic discharges. The inhibitory effect of adrenaline (ED₅₀=0.5 μM) on the respiratory rhythm was stronger than NA (ED₅₀=5 μM). The adrenaline respiratory rhythm depression was partially blocked by the α₁-antagonist prazosin or by the α₂-antagonist yohimbine. The C4 tonic discharge elicited by adrenaline was blocked by the α₁-antagonist prazosin. The direct effects of adrenaline on pre-inspiratory (Pre-I) neurons were examined in a synaptic blockade solution (low Ca), and fifty-six percent of Pre-I neurons were found to continue firing. In low-Ca solution, Pre-I neurons were excited (n=29 of 39) or depressed (n=5 of 39) by adrenaline, and excited by α₁-agonist phenylephrine or depressed by α₂-agonist clonidine. These results suggest that the respiratory rhythm depression under intact network conditions is mediated by some other inhibitory system. The inhibitory effect of adrenaline on the respiratory rhythm was partially blocked by the GABA_A-antagonists bicuculline or picrotoxin, but not by the GABA_B-antagonist phaclofen. The present results suggest that: (1) respiratory rhythm generation is more sensitive to adrenaline than NA through α-adrenergic action of adrenaline; (2) the activity of Pre-I neurons could be directly regulated by excitation via α₁-receptors and inhibition via α₂-receptors; and (3) the depression of the respiratory rhythm by adrenaline is partly mediated by GABA_Aergic neurons. Received: 8 April 1997 / Accepted: 6 October 1997     

Production of CA125 by human lung cancer cell lines

CA125, which until recently was considered an ovary specific tumor marker, is elevated in the serum of patients with many pathological conditions, including lung cancer. In order to investigate the production of CA125 by human lung cancer cell lines, cell culture and immunochemical staining were performed in three cell lines. Our results showed the cell surface expression of CA125 in both adenocarcinoma and large cell carcinoma cell lines and the production of CA125 in culture medium. This is considered as evidence for in vitro production of CA125 by human lung cancer, and suggests that CA125 elevation is not only the result of ovarian cancer but may be due to other pathological conditions, including lung cancer.     

Sotos syndrome associated with a de novo balanced reciprocal translocation t(5;8)(q35;q24.1).

We describe a de novo balanced reciprocal translocation between the long arms of chromosomes 5 and 8 [46,XX,t(5;8)(q35;q24.1)] in a 15-month-old girl with a typical Sotos syndrome phenotype. Involvement of the 5q35 region was previously reported (Maroun et al. [1994: Am J Med Genet 50:291-293]) as one of translocation breakpoints in the present patient. We suggest that the gene responsible for Sotos syndrome is located to a distal long-arm region of chromosome 5.     

Total energy expenditure of elite synchronized swimmers measured by the doubly labeled water method

To determine the daily energy requirement of elite synchronized swimmers during moderate-intensity training, the average daily energy expenditure measured by the doubly labeled water method, was calculated for nine female Japanese national team synchronized swimmers [four senior; mean (SD) 22.5 (1.0) years old, 52.2 (3.6) kg, and five junior; 17.6 (1.1) years old, 52.8 (2.3) kg]. Their total energy expenditure (TEE) was 11.5 (2.8) MJ · day⁻¹ [2738 (672) kcal · day⁻¹]. When compared with estimated energy requirements derived from “Recommended Dietary Allowances for the Japanese”, 12.1 (0.6) MJ · day⁻¹ [2897 (139) kcal · day⁻¹], there was no difference between mean actual and estimated energy requirements. However, there were considerable differences observed on an individual basis. Their energy intake, estimated from 7- day self-reported dietary records, was 8.9 (1.7) MJ · day⁻¹ [2128 (395) kcal · day⁻¹], which was significantly lower than their TEE (P < 0.05). Resting energy expenditure (REE), as determined by indirect calorimetry, was 5.2 (0.3) MJ · day⁻¹ [1247 (75) kcal · day⁻¹]. Their physical activity level (TEE/REE) was 2.18 (0.43). These results demonstrate that the TEE values of elite female synchronized swimmers are not dissimilar to those reported for athletes participating in other sports, especially competitive swimmers during moderate-intensity training. Accepted: 26 May 2000     

The relationships between autonomic function and heart rate in essential hypertension

The circadian variation of blood pressure (BP) may be mediated at least in part by circadian variation of autonomic nervous system activity. In the present study power spectral analysis of hourly R-R intervals for 24 hours was done to obtain the low frequency variability (LF: 0.04 to 0.15Hz) and high frequency variability(HF: 0.15 to 0.40Hz) in 93 patients with untreated essential hypertension. LF/HF ratio and HF were considered to be an index of sympathetic nervous activity and parasympathetic nervous activity, respectively. The relationship between heart rate (HR) and systolic blood pressure (SBP), diastolic blood pressure (DBP), HF, and LF/HF was examined. Both SBP and DBP were correlated positively with HR(r = 0.28, p < 0.05 and r = 0.27, p < 0.05, respectively) in the daytime. HF was correlated negatively and significantly with HR in both daytime and nighttime (r = -0.40, p < 0.05, and r = -0.38, p < 0.05 respectively). After averaging for SBP of 24 hours, HR in the patients whose SBP was 135mmHg or more was significantly higher than that in the patients whose SBP was less than 135mmHg. These results suggest that the decreased parasympathetic nervous activity seems to be responsible for the rise in BP.     

Male with type II autosomal recessive cutis laxa

A 5-year-old boy, who had pre- and postnatal growth retardation, delayed motor development, cutis laxa, delayed closure of large fontanels, congenital hip dislocation and characteristic facies, is described. Disorders with cutis laxa are now divided into five types. The patient had clinical manifestations very similar to those of cutis laxa with bone dystrophy (type II autosomal recessive cutis laxa). Eighteen patients have been reported, the ratio of males to females being 5 to 14. This is the fifth case of this disorder occurring in a male, which provides further evidence for autosomal recessive inheritance.     

New medical education of laboratory medicine at Tohoku University

The purpose of this paper is to give an insight into the medical education program of our division at Tohoku University. Laboratory medicine in medical education is a field of learned basic clinical tests. Students have to learn the clinical laboratory through early clinical exposure in the first grade and try clinical technology through small-group learning in the fifth grade. Finally, they learn laboratory medicine such as infection control in our or another clinical hospital. The objects of our course are to encourage and promote the highest standards of training and post-graduate education of physicians and scientists at our university.     

Chronic myelogenous leukemia with a complex Ph1 translocation in an XYY male

We encountered a 38-year-old Japanese male patient with chronic myelogenous leukemia (CML), whose bone marrow and peripheral blood cells during the chronic and blastic phases contained a complex Ph¹ translocation and an extra Y chromosome [i.e., 47,XYY,t(9;22;13)(q34;q11;q14)]. A karyotypic analysis of PHA-stimulated lymphocytes showed the constitutional karyotype to be 47,XYY. Thus, it was considered that CML with a complex Ph¹ translocation developed in an XYY male; such a case has not been reported, so far. A B-lymphocyte cell line with the complex Ph¹ translocation was established by the procedure of Epstein-Barr virus transformation. The presence of the complex Ph¹ translocation in the B-lymphocyte cell line suggests that some of the B lymphocytes in this patient originated from the CML clone.