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61.
Summary The ability of Kupffer cells, spleen macrophages, pulmonary macrophages, and peritoneal macrophages (PM) to produce cytotoxic factor (CTF) was investigated in vitro. The production of CTF by Kupffer cells elicited with Corynebacterium parvum (CP) or Lactobacillus casei YIT9018 (LC9018) was higher than that of spleen, pulmonary macrophages, or PM. In addition, oxygen radical (OR) production by Kupffer cells or PM was measured. The production of OR by Kupffer cells or PM was significantly augmented by i.v. or i.p. injection of LC9018 or CP. No significant correlation was observed between the increase in OR production by Kupffer cells or PM and CTF production by Kupffer cells or PM elicited with either organism. It was suggested that activated Kupffer cells may be one important source of CTF production in serum and that the CTF-producing macrophages may be different from the OR-producing macrophages.  相似文献   
62.
A new species, Mortierella sugadairana, is described for a fungus forming homothallic zygospores with a club-shaped macrosuspensor and a microsuspensor originating from the macrosuspensor. The species was isolated from cool regions in Japan and morphologically and phylogenetically close to a heterothallic species M. parvispora, which is the first species reported as a heterothallic species in the genus. Mycelial growth of the species was limited at 30 °C, whereas two isolates of M. parvispora can grow. This may indicate that the species and M. parvispora adapted to different climates from a common ancestor involving differentiation of the manner of reproduction.  相似文献   
63.
The calcium-sensing receptor (CaSR) plays an important role in sensing extracellular calcium ions and regulating parathyroid hormone secretion by parathyroid gland cells, and the receptor is a suitable target for the treatment of hyperparathyroidism. Cinacalcet hydrochloride is a representative CaSR agonist which widely used for the hyperparathyroidism. However, it has several issues to clinical use, such as nausea/vomiting and strong inhibition of CYP2D6. We tried to improve these issues of cinacalcet for a new pharmaceutical agent as a preferable CaSR agonist. Optimization from cinacalcet resulted in the identification of pyrrolidine compounds and successfully led to the discovery of evocalcet as an oral allosteric CaSR agonist. Evocalcet, which exhibited highly favorable profiles such as CaSR agonistic activity and good DMPK profiles, will provide a novel therapeutic option for secondary hyperparathyroidism.  相似文献   
64.
Abstract: To evaluate the role of various growth factors in naturally occurring cell death during development of the neural retina, we examined the effects of such factors on the nuclear morphology and the size of DNA in cultured chick embryonic neural retina cells. Basic fibroblast growth factor (bFGF) increased internucleosomal cleavage of DNA and nuclear fragmentation in a time- and dose-dependent manner. The effect was inhibited by anti-bFGF antibody, suramin, and cycloheximide. Epidermal growth factor, platelet-derived growth factor, nerve growth factor, tumor necrosis factor-α, and dexamethasone had no effect. These results provide evidence that bFGF may eventually act as a lethal factor inducing apoptotic cell death during the development of the neural retina in chick embryo.  相似文献   
65.
A novel type of zygospore formation is described in the heterothallic speciesMortierella capitata, which was repeatedly isolated from soils inhabited by pillbugs (Armadillidium vulgare, Isopoda). Zygospore formation was induced on media containing sterilized arthropods. Anisogamy and colorless zygospore walls are shared with other zygosporic species ofMortierella, but a unique feature ofM. capitata is the production of zygospores on elongated macrosuspensors which are covered by branches of the microsuspensors. This kind of zygosporogenesis is termed “capitata-type” here. The taxonomic position ofM. capitata is discussed based on the zygospore characteristics.  相似文献   
66.
The interaction between the T cell activation antigen gp39 and CD40, its receptor CD40 on B cells, plays a critical role in the regulation of humoral immune responses. Using a detailed three-dimensional model of the gp39 extracellular region, we have analyzed 20 mutations in gp39 that were, with one exception, isolated from patients with X-linked hyper IgM (XHIM) syndrome. On the basis of this analysis, the mutations were classified according to their predicted locations and effects. Twelve mutations are thought to compromise the gp39 structure by affecting interactions in hydrophobic core regions or at monomer interfaces, whereas seven others map closely to gp39 residues important for interaction with CD40. The latter mutations may thus, directly or indirectly, interfere with CD40 binding. One naturally occurring mutant whose carrier displays normal immune responses maps to a solvent-exposed position in a loop region of the molecule.  相似文献   
67.
68.

Background

Lung transplantation has been established as the definitive treatment option for patients with advanced lymphangioleiomyomatosis (LAM). However, the prognosis after registration and the circumstances of lung transplantation with sirolimus therapy have never been reported.

Methods

In this national survey, we analyzed data from 98 LAM patients registered for lung transplantation in the Japan Organ Transplantation Network.

Results

Transplantation was performed in 57 patients as of March 2014. Survival rate was 86.7% at 1 year, 82.5% at 3 years, 73.7% at 5 years, and 73.7% at 10 years. Of the 98 patients, 21 had an inactive status and received sirolimus more frequently than those with an active history (67% vs. 5%, p<0.001). Nine of twelve patients who remained inactive as of March 2014 initiated sirolimus before or while on a waiting list, and remained on sirolimus thereafter. Although the statistical analysis showed no statistically significant difference, the survival rate after registration tended to be better for lung transplant recipients than for those who awaited transplantation (p = 0.053).

Conclusions

Lung transplantation is a satisfactory therapeutic option for advanced LAM, but the circumstances for pre-transplantation LAM patients are likely to alter with the use of sirolimus.  相似文献   
69.
Sphingomyelin from the guinea pig Harderian gland was isolated and characterized. The purified sphingomyelin gave a broad spot on thin-layer chromatography. The fatty acid composition of the whole sphingomyelin was 71% nonhydroxy acids and 29% 2-hydroxy acids. Methyl-branched fatty acids were only 2% of the total acids. The long-chain bases were composed of straight-chain sphingenines (50%) and sphinganines (6%). Methyl-branched long-chain bases were 44% of the bases. The sphingomyelin was further separated into four fractions (I, II, III, IV) by high-performance liquid chromatography. The ratio of fractions I, II, III, and IV was approximately 2:5:2:1, respectively. The fatty acids of fractions I and II consisted of nonhydroxy acids and those of fractions III and IV were 2-hydroxy acids. The long-chain bases of fractions I and III were sphinganines including 10-, 9-, and 8-methylsphinganines and anteiso-sphinganines. These methyl-branched bases occupied about 70% of the total sphinganines. The long-chain bases of fractions II and IV consisted of sphingenines. The methyl-branched unsaturated bases were only 30% of the total sphingenines, all in the anteiso-form. Thus, the sphingomyelin obtained from guinea pig Harderian gland had complex compositions of fatty acids and long-chain bases, and half the number of long-chain bases had methyl branches. The methyl-branched fatty acids were only a minor component. These characteristics are similar to those of cerebrosides isolated from the same source.  相似文献   
70.
Microsomal sn-glycerol 3-phosphate acyltransferase from the guinea pig Harderian gland was studied. Its specific activity (1.0 nmol/min X mg, with palmitoyl-CoA as a substrate) was almost the same as that of the rat liver microsomal enzyme. The enzyme acted on various types of acyl-CoA, the relative reaction rates being as follows: palmitoyl-CoA, 100(%); stearoyl-CoA, 30; oleoyl-CoA, 50; linoleoyl-CoA, 40; and arachidonoyl-CoA, 20. When assayed in the presence of 1 mM 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB), the activity on palmitoyl-CoA was inhibited by only 20-30%, whereas those for other acyl-CoAs were completely abolished. The DTNB-resistant activity was inhibited by 0.1 mM dihydroxyacetonephosphate and 0.5 mM dithiothreitol, whereas the DTNB-sensitive activity was not affected. Furthermore, heat treatment at 50 degrees C for 15 min abolished most of the DTNB-sensitive activity, but not the DTNB-resistant activity. These results, taken together, suggested that the microsomal fraction of the guinea pig Harderian gland contained at least two types of sn-glycerol 3-phosphate acyltransferase, and that, in contrast to in the case of rat liver microsomes, a DTNB-resistant enzyme that utilized exclusively palmitoyl-CoA was predominant.  相似文献   
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