Continuous measurement of oxygen consumption using the reversed fick method

We developed a continuous oxygen consumption (Vo₂) measurement system employed the reversed Fick method, in which Vo₂ in computed from continuously measured sured arterial and mixed venous oxygen saturation assed by pulse oximetry and mixed venous oximetry, respectively, and cardiac output by the heat deprivation technique. This system was compared with the conventional intermittent reversed fick method in 7 patients during surgery and with indirect calorimetry in 4 intensive care unit (ICU) patients. The Vo₂ measured by the continuous reversed Fick method showed a high correlation with those simultaneously measured by the intermittent Fick method (r=0.97,P<0.01) and by indirect calorimetry (r=0.74,P<0.01). The 95% confidence limits (bias±2 SD) of the continuous reversed Fick method were −0.6±45 ml·min⁻¹ with the intermittent Fick method and −31±56 ml·min⁻¹ with indirect calorimetry. The continuous Fick method is in satisfactory agreement with the conventional methods for the measured of Vo₂ and potentially allows for convenient assessment of Vo₂ in critically ill patients. This study was supported in part by Grants-in-Aid for the Encouragement of Young Scientists 01771185 and 04857171 from the Ministry of Education, Science and Culture of Japan     

Human T-cell leukemia virus type I associated lymphadenitis.

Histopathologic changes in lymph nodes were examined from ten patients with mild lymphadenopathy, a few atypical lymphocytes in their peripheral blood, skin lesions, and proviral DNA of human T-cell leukemia virus type I (HTLV-I) in their nodes. The proviral DNA of HTLV-I was detected by southern blot analysis, in situ hybridization, and/or polymerase chain reaction techniques. The lymph nodes showed preserved nodal architecture with diffuse infiltration of small to intermediate-sized lymphocytes in association with scattered transformed lymphocytes and a few immunoblast-like cells in the enlarged paracortex. The infiltrating lymphocytes were positive for CD4, but neither rearrangement nor deletion of T-cell receptors and immunoglobulin heavy chain genes was detected. Eight of ten patients received no therapy, and all patients were alive and healthy more than 5 months after the biopsies. The histologic findings resembled those of a viral infection and could be distinguished from HTLV-I associated lymphomas.     

Effects of a protein-free diet on the rat stomach

The effects of a protein-free diet containing a mixture of free amino acids on the stomach were studied using male Wistar strain rats. In the forestomach, thickening of mucosa and hyperkeratosis appeared and papillomas frequently developed, but they did not occur in the control rats fed a semipurified diet. Mucous neck cells increased and parietal cells and chief cells decreased in the fundus. Goblet cells occurred in the antral glands, and intestinal metaplastic glands developed in the late stage of the experiment. The number of deoxyribonucleic acid-synthesizing cells in the glandular stomach was significantly higher than that of the control. Moreover, in the antrum, somatostatin-producing cells increased in the early stage and gastrin-producing cells decreased in the late stage. These results suggest that dietary protein might play a crucial role in the differentiation of gastric epithelium and the development of intestinal metaplasia in the stomach.     

Effects of suramin on metastatic ability,proliferation, and production of urokinase-type plasminogen activator and plasminogen activator inhibitor type 2 in human renal cell carcinoma cell line SN12C-PM6

Effects of suramin, a polysulfonated naphthylurea compound, on metastatic ability, proliferation, and production of plasminogen activators and plasminogen activator inhibitors were studied using the highly metastatic human renal cell carcinoma cell line, SN12C-PM6. After renal subscapular implantation of tumor cells in nude mice, suramin significantly inhibited metastasis of tumor cells to the lungs and liver. In vitro growth of tumour cells was inhibited by suramin in a dose-dependent manner, at relatively low doses (ID₅₀ = 105 µg/ml). Plasminogen activator inhibitor type 2 (PAI-2) production by tumor cells was enhanced by suramin (100 µg/ml), whereas urokinase-type plasminogen activator (uPA) production was suppressed. Thus, the increase in PAI-2 and the decrease in uPA production correlated with the inhibitory effects on tumour growth and metastasis by suramin. Therefore suramin may be beneficial for the treatment of patients with an early stage of renal cancer with potential risk of metastasis.     

Disseminated necrotizing encephalopathy induced by methotrexate therapy alone

This report describes the autopsy findings in a 62-year-old woman who died of pneumonia and disseminated necrotizing encephalopathy following intrathecal methotrexate (MTX) therapy for meningeal infiltration of lymphoma cells. Radiation therapy was not given. An interesting pathological finding was exudation of fibrin around the small vessels in the demyelinated foci, suggesting increased vascular permeability. This observation and analysis of previous reports of similar cases suggest that primary vascular injury, probably due to the direct effect of MTX, may be involved in the pathogenesis of MTX-related disseminated necrotizing encephalopathy.     

Nucleotide sequence of dengue type 3 virus genomic RNA encoding viral structural proteins

Complementary DNAs to the 5 proximal region of the dengue virus type 3 RNA were cloned into bacterial plasmids and the nucleotide sequence of 3,000 bases from the 5 terminus of the genome were determined by DNA and RNA sequencing methods using dideoxy chain-termination reactions. Comparison of the nucleotide sequence thus obtained with those of other flavivirus genomes revealed significant homology existing in nucleotide sequence of the flavivirus genomes. When we compared amino acid sequence deduced from the nucleotide sequence with those of other flaviviruses, this genome region was found to include sequences encoding three viral structural proteins C, M, and E and a part of the viral nonstructural protein NS1 in this order in addition to the 5-noncoding sequence. The characteristics and functions of these proteins were discussed based on the deduced amino acid sequences and their hydrophobic profiles. The genetic relationship of flaviviruses was also discussed based on the genetic variation observed in their genomes.     

PROGRESSIVE MULTIFOCAL LEUKOENCEPHALOPATHY

Clinical, light- and electron microscopic, and immunohistochemical findings of a 44-year-old woman with progressive multifocal leukoencephalopathy were presented. Autopsy revealed a wide distribution of the demyelinating lesion in the cerebrum, cerebellum, brain stem and spinal cord, and intranuclear inclusion bodies and papova-like virions in transmission electron microscopy in the nuclei of oligodendrocytes. SV40 antigen was immunohistochemically detected in these inclusion bodies. The widespread extension of the lesions seemed to correlate with the duration of the patient's illness. The prolongation of the clinical course in this case may be dependent upon the lack of serious underlying diseases except for a small nodule of thyroid carcinoma, SV40 infection rather than JC virus infection and/or improved care of that kind of patient.     

Adrenomedullin and proadrenomudullin N-terminal 20 peptide (PAMP) are present in human colonic epithelia and exert an antimicrobial effect

The hypotensive and vasorelaxing peptides adrenomedullin (AM) and its gene-related peptide, proadrenomedullin N-terminal 20 peptide (PAMP), were found to be distributed on the surface of the colonic mucosa. AM and PAMP showed dose-dependent antimicrobial activity against E. coli. The results suggest that the novel vasoactive peptides AM and PAMP play an important role in mucosal defence.     

Fear conditioning-induced plasticity in auditory thalamus and cortex: To what extent is it expressed during slow-wave sleep?

After fear conditioning to a tone, rats received nonawakening presentations of the tone alone during slow-wave sleep (SWS) episodes. Multiunit activity was recorded in the medial part of the medial geniculate (MGm) and in the primary auditory cortex (ACx). Although tone-evoked responses were increased in MGm and ACx during the 3 conditioning sessions, group data failed to show any significant changes during SWS. Nonetheless, the few recordings (5/29) that exhibited the strongest conditioned responses during wakefulness expressed enhanced responding during SWS. Compared with previous data obtained in MGm during paradoxical sleep, associative plastic changes were less easily expressed during SWS. These results are discussed with regard to functional changes that occur in the thalamocortical system across vigilance states.