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141.
BACKGROUND: The cytologic appearance of basaloid squamous carcinoma (BSC) arising in the lower respiratory tract has not been described very well because of its rarity. This article describes a surgical case of bronchial BSC and provides the first documentation of the sputum and imprint cytologic features of the tumor. CASE: A 74-year-old man presented with hemoptysis. An abnormal intrabronchial mass was revealed by computed tomography and bronchoscopy. Preoperative cytology and biopsy showed that the mass was composed of small, round, atypical cells, but correct diagnosis was difficult. Under a tentative diagnosis of small round cell carcinoma, a right lobectomy was performed. The resected tumor was composed of small cells showing peripheral palisading and partial epidermoid differentiation. There was no glandular differentiation. Focal necrosis was also noted. Immunohistochemical markers for smooth muscle and neuroendocrine cells were negative. The tumor was eventually diagnosed as BSC or basaloid carcinoma (BC) with squamous differentiation. CONCLUSION: It is important to recognize this disease, especially when undetermined small round cell carcinoma is noted in cytologic specimens, in order to properly assess prognosis. Cytologic detection of nuclear palisading of the neoplastic cells, one of the hallmarks of the disease, may be difficult, however, careful examination to reveal neoplastic cells showing squamous differentiation appears helpful for diagnosis.  相似文献   
142.
143.
We have reported that the administration of di(2-ethylhexyl)phthalate (DEHP) increased the formations of quinolinic acid (QA) and its lower metabolites on the tryptophan-niacin pathway. To discover the mechanism involved in disruption of the tryptophan-niacin pathway by DEHP, we assessed the daily urinary excretion of QA and its lower metabolites, and enzyme activities on the tryptophan-niacin pathway. Rats were fed with a niacin-free, 20% casein diet or the same diet supplemented with 0.1% DEHP or 0.043% phthalic acid and 0.067% 2-ethylhexanol added for 21 days. Feeding of DEHP increased the urinary excretions of QA and its lower metabolites in a time-dependent manner, and the increase of these excretions reached a peak at 11 days, but feeding of phthalic acid and 2-ethylhexanol had no effect. Feeding of DEHP, however, did not affect any enzyme activity including alpha-amino-beta-carboxymuconate-epsilon-semialdehyde decarboxylase (ACMSD), affecting the formation of QA, on the tryptophan-niacin pathway.  相似文献   
144.
Aspergillus oryzae produces multinucleate conidia, which makes the obtaining of homokaryons labor-intensive. Analysis of conidia by flow cytometry clarified the relationship that conidia of lower nuclear number were smaller in size. Based on this, we have developed a simple way to enrich uninucleate conidia with a membrane filter. Our results also suggest that the method is useful for elimination of heterokaryons.  相似文献   
145.
Cysteinyl residues in proteins were alkylated with acrylamide during sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) to yield a thioether derivative, cys-S-beta-propionamide (PAM cys). The process was termed in situ alkylation with acrylamide. Using this method, the recovery of PAM-cys peptides from bovine serum albumin (BSA) was 88.6% at 10 picomol in one-dimensional (1-D) SDS-PAGE and 97.1% at 50 picomol in two-dimensional (2-D) SDS-PAGE. The coverage of tryptic peptide of BSA in 1-D and 2-D SDS-PAGE was 83.7% and 81.1%, respectively. The advantages of in situ alkylation with acrylamide were the following: (i) cysteinyl peptides were effectively derived in a single PAM cys and then proteins were precisely identified using databases; (ii) marked reduction of salts compared with post alkylation, e.g., using carboxymethylamide (CAM), resulting in higher signal intensity and wider coverage of cysteinyl peptides from PAM cys, compared with those of CAM derivatives, in mass spectrometry peptide mapping; and (iii) shorter duration by excluding the processes of post alkylation and desalting before peptide mapping.  相似文献   
146.
BACKGROUND: In allergic inflammation involving allergic rhinitis, the predominance of Th(2) lymphocytes is one of the primary causal agents in promotion of the allergic condition. Thymus and activation-regulated chemokine (TARC/CCL17) is a recently identified chemokine that induces the development of Th(2) lymphocytes. One of the sources of TARC has been reported to be peripheral blood mononuclear cells (PBMCs). OBJECTIVE: We investigated TARC production from PBMCs by the stimulation of specific antigens and Th(2) type cytokines. METHOD: PBMCs were isolated from both allergic rhinitis patients and healthy volunteers. PBMCs were incubated with cytokine. TARC mRNA expression was examined by real time PCR methods and the amount of TARC production was examined by ELISA. RESULTS: IL-13 was found to be the most potent inducer for TARC mRNA expression and protein production in PBMCs. Furthermore, tumour necrosis factor alpha and IL-13 synergistically induce TARC. The amount of TARC from allergic rhinitis patients was significantly larger than that from healthy volunteers. Moreover, TARC was induced by a specific antigen, and was 35% inhibited by an anti-IL-13 neutralizing antibody. CONCLUSION: These results indicate that IL-13 is important in TARC mediated Th(2) lymphocytes infiltration in the nasal mucosa.  相似文献   
147.
Matsui T  Omasa K 《Annals of botany》2002,89(6):683-687
We examined the relationship between morphological characteristics of anthers and fertility in japonica rice cultivars subjected to high temperature (37.5(26 degrees C day/night) at flowering. Percentage fertility was negatively correlated with the number of cell layers that separated the anther locule from the lacuna that formed between the septum and the stomium. The cell layers consisted of the remaining septum and degraded tapetum, and serve to keep the adjacent two locules closed. Anther dehiscence therefore requires the rupture of the cell layers. We conclude that the tight closure of the locules by the cell layers delayed locule opening, and decreased fertility at high temperatures.  相似文献   
148.
To examine the effects of aggregation-inducing motifs related to neurodegenerative diseases on amyloid formation of host protein, we prepared several chimera myoglobins, in which various aggregation-inducing motifs were inserted. The focused aggregation-inducing motifs included five (R5) or two (R2) oligopeptide repeats in yeast Sup35p, five octapeptide repeats (OPR) in the human prion protein, a nonamyloid beta component (NAC) in alpha-synuclein, and tandem repeats of 50 glutamines (Q50). Circular dichroism and infrared spectroscopies suggested that the OPR, R5, and Q50 motifs formed an antiparallel beta sheet as well as a random coil, whereas the R2 and NAC motifs mainly formed random coils. The OPR, R5, and Q50 mutants, but not the R2 and NAC mutants, readily formed the SDS-resistant aggregates under physiological condition, and electron microscopy revealed that the aggregates contained amyloid fibrils. The destabilization and increase in gyration radius of the OPR, R5, and Q50 mutants correlated with the tendency to form amyloid fibrils. A control mutant bearing a nonamyloidgenic sequence was also moderately destabilized but did not form amyloid fibrils. Therefore, we concluded that the OPR, R5, and Q50 motifs, even in a quite stable protein such as myoglobin, led the host protein to formation of amyloid fibrils under physiological condition.  相似文献   
149.
KPNAYKGKLPIGLWamide, a novel member of the GLWamide peptide family, was isolated from Hydra magnipapillata. The purification was monitored with a bioassay: contraction of the retractor muscle of a sea anemone, Anthopleura fuscoviridis. The new peptide, termed Hym-370, is longer than the other GLWamides previously isolated from H. magnipapillata and another sea anemone, A. elegantissima. The amino acid sequence of Hym-370 is six residues longer at its N-terminal than a putative sequence previously deduced from the cDNA encoding the precursor protein. The new longer isoform, like the shorter GLWamides, evoked concentration-dependent muscle contractions in both H. magnipapillata and A. fuscoviridis. In contrast, Hym-248, one of the shorter GLWamide peptides, specifically induced contraction of the endodermal muscles in H. magnipapillata. This is the first case in which a member of the hydra GLWamide family (Hym-GLWamides) has exhibited an activity not shared by the others. Polyclonal antibodies were raised to the common C-terminal tripeptide GLWamide and were used in immunohistochemistry to localize the GLWamides in the tissue of two species of hydra, H. magnipapillata and H. oligactis, and one species of sea anemone, A. fuscoviridis. In each case, nerve cells were specifically labeled. These results suggest that the GLWamides are ubiquitous among cnidarians and are involved in regulating the excitability of specific muscles.  相似文献   
150.
Phylogenetic relationships of the three lygosomine skink genera occurring both in the Old World and the New World (Mabuya, Scincella and Sphenomorphus) were inferred from mitochondrial DNA sequence of 12S and 16S rRNA genes. Results strongly suggested the non-monophyly for any of these three genera. Within the Mabuya group, Asian members appear to have diverged first, leaving the Neotropical and the Afro-Malagasy Mabuya as sister groups. These relationships, together with the absence of extant or fossil representatives of the Mabuya group from North America, strongly suggest the trans-Atlantic dispersals of Mabuya from Africa to Neotropics. Our results also indicated a closer affinity of the New World Scincella with the New World Sphenomorphus than with the Old World Scincella. Such relationships suggest the trans-Beringian dispersal of the common ancestor from Asia and its subsequent divergence into the North American Scincella and the Neotropical Sphenomorphus.  相似文献   
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