Increase of DNA synthesis in uterine adenomyosis in mice with ectopic pituitary isograft.

Ectopic pituitary isografts (EPI) have been found to induce a high incidence of uterine adenomyosis in SHN mice. All the SHN mice given EPI in the right uterus at 40 days of age developed uterine adenomyosis, and more than 80% of mice showed the genesis of subserosal nodules, an advanced state of adenomyosis, 65 days after EPI. Activities of both thymidylate synthetase and thymidine kinase, i.e. DNA-synthesizing enzymes in de novo and salvage pathways of pyrimidine metabolism, respectively, were significantly increased in EPI-induced uterine adenomyosis to approximately 2-fold those in normal control uteri. Bromodeoxyuridine-immunoreactive cells were regarded as the cells in S phase, and the number in the endometrial epithelium and stroma in EPI-induced uterine adenomyosis was more than 1.5-fold that in normal control uteri. EPI may affect the genesis of uterine adenomyosis generally, but not locally, because there were no differences between the right uterus with EPI and the left without EPI in the incidence of adenomyosis, histology or DNA-synthesizing enzyme activities.     

Molecular cloning and characterization of an alkalophilic Bacillus sp. C125 gene homologous to Bacillus subtilis sec Y.

A 1.8 kb HindIII DNA fragment containing the secY gene of alkalophilic Bacillus sp. C125 has been cloned into plasmid pUC119 using the B. subtilis secY gene as a probe. The complete nucleotide sequence of the cloned DNA indicated that it contained one complete ORF and parts of two other ORFs. The similarity of these ORFs to the sequences of the B. subtilis proteins indicated that they were the genes for ribosomal protein L15-SecY-adenylate kinase, in that order. The gene product of the alkalophilic Bacillus sp. C125 secY homologue was composed of 431 amino acids and its M(r) value has been calculated to be 47,100. The distribution of hydrophobic amino acids in the gene product suggested that the protein was a membrane integrated protein with ten transmembrane segments. The total amino acid sequence of alkalophilic Bacillus sp. C125 secY homologue showed 69.7% homology with that of B. subtilis secY. Regions of remarkably high homology (78% identity) were present in transmembrane regions, and cytoplasmic domains (73% identity) with less homologous regions present in extracellular domains (43% identity).     

Calcifying nested stromal epithelial tumor of the liver in a patient with Klinefelter syndrome: a case report and review of the literature

Background

Calcifying nested stromal epithelial tumor (CNSET) is a primary neoplasm of the liver, characterized by well-demarcated nests consisting of spindle and epithelioid cells with calcification and bone formation. An association of Cushing syndrome with CNSET has drawn attention, but the origin of CNSET has not been clarified.

Case presentation

We report here the case of a 20-year-old male with Klinefelter syndrome who underwent liver resection for an increasing liver tumor that was pathologically diagnosed with CNSET. He was postoperatively followed up and received several examinations, and recurrences and extrahepatic lymph node metastases were detected on the 64th day after surgery. Chemoembolization and chemotherapy were not effective, leading to tumor progression with development of progressive liver failure, and the patient finally died 164 days after hepatectomy.

Conclusions

This case suggests that an imbalance of hormones affects the genesis and progression of CNSET, and indicates the importance of closely following patients with CNSET by imaging with attention to hepatic recurrence and extrahepatic metastases.

     

Glucose transport system in a facultative iron-oxidizing bacterium, Thiobacillus ferrooxidans

Properties of a heat-labile glucose transport system in Thiobacillus ferrooxidans strain AP-44 were investigated with iron-grown cells. [14C]glucose was incorporated into cell fractions, and the cells metabolized [14C]glucose to 14CO2. Amytal, rotenone, cyanide, azide, 2,4-dinitrophenol, and dicyclohexylcarbodiimide strongly inhibited [14C]glucose uptake activity, suggesting the presence of an energy-dependent glucose transport system in T. ferrooxidans. Heavy metals, such as mercury, silver, uranium, and molybdate, markedly inhibited the transport activity at 1 mM. When grown on mixotrophic medium, the bacteria preferentially utilized ferrous iron as an energy source. When iron was exhausted, the cells used glucose if the concentration of ferrous sulfate in the medium was higher than 3% (wt/vol). However, when ferrous sulfate was lower than 1%, both of the energy sources were consumed simultaneously.     

Regulation of the murine IgE antibody response. I. Characterization of suppressor cells regulating both persistent and transient responses and their sensitivity to low doses of X-irradiation.

Anti-ovalbumin (OA) IgE antibody responses were measured in B6D2F1 mice as a function of time and antigen dose. One hundred to 200 microgram of OA in Al(OH)3 elicited transient responses, whereas 1 to 10 microgram of OA in Al(OH)3 elicited persistent anti-OA IgE responses of high titer. T cells isolated from the spleens of mice mounting either a persistent or a transient response strongly suppressed primary anti-DNP IgE responses in unirradiated recipient mice that were immunized with DNP-OA in Al(OH)3; it was, therefore, concluded that suppressor T cells (Ts cells) were activated during both the persistent and transient IgE responses. Nevertheless, in the present study it was not possible to completely rule out the contention that IgG antibodies may also have been suppressing the IgE response. With a modified adoptive transfer system, it was shown that these Ts cells were sensitive to low doses (250 R) of x-irradiation. The suppressive activity of long-term OA primed cells was also shown to be markedly enhanced when cultured for 24 hr with soluble OA; this finding was interpreted to indicate the presence of memory suppressor cells.     

Characterization of an Anion Transporter in the Plasma Membrane of Barley Roots

To examine the relationship between H⁺-ATPase and the transportof anions, we investigated the effects of various inhibitorson the activity of the H⁺-ATPase, the transport of protons,and the transport of Cl^- ions using plasma membrane vesiclesprepared from barley roots. Some inhibitors, namely, 4,4-diisothiocyano-2,2-stilbenedisulfonate (DIDS) and Zn²⁺ ions markedly inhibited H⁺- ATPaseactivity. Other compounds, such as phenylglyoxal (PGO) and niflumicacid (NIF), inhibited H⁺-ATPase activity by 20-30%, while anthracene-9-carboxylate(A-9-C) and tetraethylammonium chloride (TEA-Cl) had littleeffect on this activity. The ATP-dependent acidification ofthe interior of vesicles was strongly dependent on the presenceof permeant anions, such as chloride (Cl^-) and nitrate (NO₃^-),and it was completely inhibited by 0.2 mM NIF. Other compounds,namely, A-9-C of 0.1 mM and TEA-Cl of 10 mM, did not affectH⁺-transport activity. The inhibition of H⁺-transport activityby NIF was observed even when the activity was assayed in thepresence of KCl, KNO₃, or bis-tris-propane (BTP)-Cl. Using ³⁶cl,we quantified Cl^--transport activity by measuring the uptakeof Cl^- ions into the plasma membrane vesicles. The uptake dependedon the potential difference across the membrane that was generatedby H⁺-ATPase; it was enhanced by an inside-positive potentialgradient. At 0.1 mM, NIF completely blocked the voltage-dependentCl^--transport activity. From these properties of the Cl^- transporterand the inhibition of H⁺-transport activity by NIF, we suggestthat H⁺-transport activity across the plasma membrane mightbe modulated by the transport of anions via a NIF-sensitiveanion-permeable transporter that acts to collapse the inside-positivepotential generated by H⁺-ATPase. (Received September 7, 1995; Accepted July 23, 1996)     

Endothelin-3 stimulates inositol 1,4,5-trisphosphate production and Ca2+ influx to produce biphasic dopamine release from rat striatal slices

Summary 1. Real-time monitoring of dopamine (DA) release from rat striatal slices demonstrated that endothelin (ET)-3 (0.1–10M) produced a biphasic DA release consisting of transient and sustained components. When extracellular Ca²⁺ was removed, the sustained but not transient response remarkably decreased.2. ET-3 (1–10M) stimulated an increase in the intracellular Ca²⁺ concentration ([Ca²⁺]_i), which also consisted of two components. The external Ca²⁺ depletion inhibited primarily the sustained component of the Ca²⁺ response to ET-3.3. ET-3 increased inositol 1,4,5-trisphosphate (IP3) concentrations in striatal slices. This response peaked at 10 to 20 sec and returned to the basal level 2 min after stimulation, an event which was in good accord with a prompt and transient phase of both cytosolic Ca²⁺ activity and DA release evoked by ET-3.4. Thus, ET-3 produces a transient and a sustained release of DA from striatal slices by stimulating intracellular Ca²⁺ mobilization via IP3 formation and extracellular Ca²⁺ influx, respectively.     

Distribution of angiotensinogen in diseased human hearts

Extrahepatic synthesis and localization of angiotensinogen (ATN) have been described in animals, thus establishing the tissue renin-angiotensin (RA) system. However, there had been no reports of tissue RA systems in human organs, including the heart. In earlier, we have reported the possibility of ATN synthesis in the human heart using ribonuclease protection assay system. ATN mRNA was detected not only in the liver, but also in both the atrial and ventricular heart tissues, suggesting that ATN is synthesized in the human heart. In this report, we looked for the distribution of ATN in diseased human heart.Northern blot hybridization of cDNA with total RNA extracted from human liver, brain, kidney, atrial and ventricular tissues revealed that ATN mRNA exists in cardiac ventricule.Immunohistochemical studies using a specific antibody to ATN revealed a stronger reaction in the endocardial layer of the human left ventricle, than in the epicardial layer, and intense immunoreactivity in the conduction system and right atrium. This distribution pattern was similar to that of human atrial natriuretic peptide (hANP), which functions a smooth muscle relaxant. Double immunostaining of ATN and hANP demonstrated that all myocytes in the right atrium had immunopositive reactions to ATN, hANP or both of ATN and hANP. Double immunoelectron staining enabled us to show more detailed localization of ATN and hANP; hANP only existed in the specific granules and ATN existed in the myofibril, but not in the granule. Furthermore, our experiments provide evidence of ATN in healthy human hearts and also reveal a widespread immunopositive reaction for ATN in the left ventricle of diseased hearts.     

A new non-orthogonal decomposition method to determine effective torques for three-dimensional joint rotation

This paper describes a new non-orthogonal decomposition method to determine effective torques for three-dimensional (3D) joint rotation. A rotation about a joint coordinate axis (e.g. shoulder internal/external rotation) cannot be explained only by the torque about the joint coordinate axis because the joint coordinate axes usually deviate from the principal axes of inertia of the entire kinematic chain distal to the joint. Instead of decomposing torques into three orthogonal joint coordinate axes, our new method decomposes torques into three "non-orthogonal effective axes" that are determined in such a way that a torque about each effective axis produces a joint rotation only about one of the joint coordinate axes. To demonstrate the validity of this new method, a simple internal/external rotation of the upper arm with the elbow flexed at 90 degrees was analyzed by both orthogonal and non-orthogonal decomposition methods. The results showed that only the non-orthogonal decomposition method could explain the cause-effect mechanism whereby three angular accelerations at the shoulder joint are produced by the gravity torque, resultant joint torque, and interaction torque. The proposed method would be helpful for biomechanics and motor control researchers to investigate the manner in which the central nervous system coordinates the gravity torque, resultant joint torque, and interaction torque to control 3D joint rotations.