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51.
Three phases of neurogenesis can be recognized during Xenopus spinal cord development. An early peak during gastrulation/neurulation is followed by a phase of low level neurogenesis throughout the remaining embryonic stages and a later peak at early larval stages. We show here that several genes known to be essential for early neurogenesis (X-NGNR-1, XNeuroD, XMyT1, X-Delta-1) are also expressed during later phases of neurogenesis in the spinal cord, suggesting that they are involved in regulating spinal neurogenesis at later stages. However, additional neuronal determination genes may be important during larval stages, because X-NGNR-1 shows only scant expression in the spinal cord during larval stages. Thyroid hormone treatment of early larvae promotes neurogenesis in the spinal cord, where thyroid hormone receptor xTRalpha is expressed from early larval stages onward and results in precocious up-regulation of XNeuroD, XMyT1, and N-Tubulin expression. Similarly, thyroid hormone treatments of Xenopus embryos, which were coinjected with xTRalpha and the retinoid X receptor xRXRalpha, repeatedly resulted in increased numbers of neurons, whereas unliganded receptors repressed neurogenesis. Our findings show that thyroid hormones are sufficient to up-regulate neurogenesis in the Xenopus spinal cord. 相似文献
52.
We compared morphological and morphometric data on various motor neurons in the human pyramidal system using the modified Klüver-Barrera staining method with extremely minimized shrinkage ratio and an image-analyzer. We classified motor neurons in the human pyramidal system into three groups according to the measurement data. This report may be of interest to better understand the process of nerve conduction in the human pyramidal system. 相似文献
53.
Akiko Hori Masahiro Kami Sung-Won Kim Aki Chizuka Rie Kojima Osamu Imataki Michiyo Sakiyama Tamae Hamaki Yasushi Onishi Noriko Usubuchi Yukiko Kishi Naoko Murashige Kinuko Tajima Shigesaburo Miyakoshi Yuji Heike Shigeru Masuo Shuichi Taniguchi Yoichi Takaue 《Biology of blood and marrow transplantation》2004,10(1):65-72
Little information is available on the clinical characteristics of infectious complications that occur in the early period after reduced-intensity stem cell transplantation (RIST). We retrospectively investigated the clinical features of neutropenic fever and infectious episodes within 30 days after RIST in 76 patients who had received fluoroquinolones as part of their antibacterial prophylaxis. Preparative regimens included cladribine 0.66 mg/kg or fludarabine 180 mg/m2 plus busulfan 8 mg/kg. All but 1 patient survived 30 days after transplantation, and 75 patients (99%) became neutropenic within a median duration of 9 days. Neutropenic fever was observed in 29 patients (38%), and bacterial infection was confirmed in 15 (20%) of these, including bacteremia (n = 13), bacteremia plus pneumonia (n = 1), and urinary tract infection (n = 1). The causative organisms were gram-positive (n = 9) and gram-negative organisms (n = 7), with a mortality rate of 6%. Neither viral nor fungal infection was documented. Multivariate analysis showed that the presence of neutropenia at the initiation of preparative regimens was an independent risk factor for subsequent documented bacterial infections (P =.026; 95% confidence interval, 1.25-35.1). We conclude that neutropenic fever and bacteremia remain common complications in RIST. 相似文献
54.
The prevalence of TT virus (TTV) infection and its relationship to hepatitis in children 总被引:4,自引:0,他引:4
Iriyama M Kimura H Nishikawa K Yoshioka K Wakita T Nishimura N Shibata M Ozaki T Morishima T 《Medical microbiology and immunology》1999,188(2):83-89
TT virus (TTV) is a newly discovered virus from a patient with post-transfusion hepatitis. We investigated the frequency
and pathogenesis of TTV infection in children. A semi-nested PCR assay was used to amplify TTV-DNA in serum samples from 254
ambulatory children without liver disease, 20 with hepatitis of unknown etiology, and 18 transfusion recipients or hemophiliacs.
In positive samples, TTV-DNA was quantified by real-time quantitative PCR using a fluorescent probe. We detected TTV-DNA in
20% of children with hepatitis of unknown etiology, which was not statistically different from the 23% prevalence in ambulatory
children. In transfusion recipients or hemophiliacs, the frequency was higher (50%) than that in ambulatory children (P = 0.01). Among ambulatory children, TTV-DNA was frequently detected in children with acute gastroenteritis (36%). TTV-DNA
was detected in 10% of the infants under 6 months old, and 20% of the children from 7 to 12 months old. The prevalence was
constant after the age of 1 year; however, the copy number of TTV-DNA was significantly higher in children under 1 year of
age (mean: 105.4 versus 103.8 copies/ml, P= 0.008). Finally, TTV-DNA was quantified serially in three children with chronic hepatitis who were positive for TTV-DNA.
The presence or amount of TTV-DNA was unrelated to the serum alanine aminotransferase level. These results indicate that TTV
infection is common in children. The larger quantity of TTV-DNA in infants and the high prevalence of TTV in children of all
ages suggest that TTV may be transmitted in early childhood. Its relationship to hepatitis is doubtful in children.
Received: 8 April 1999 相似文献
55.
Naoko Tanda Shiro Mori Masato Nose Tetsuo Saito Shi-Taek Song Atsushi Sato Teiichi Teshima 《Pathology international》1996,46(9):639-645
The expression of -GlcNAcβ1–6Man-(β1–6) branched oligosaccharides In carcinoma cells has been considered to influence their metastatic potentials. In the present paper, the lectin histochemistry of oral squamous cell carcinomas obtained in biopsy from 34 patients with Phaseolus vulgaris leukoagglutinin (L-PHA), which potentially binds to N-glycosidic carbohydrates with β1–6 linked lactosamin antennae, was studied in order to analyze the relationship between their staining patterns and metastases. The L-PHA-binding oligosaccharides of the carcinomas were expressed on the cell surface in the following patterns: (i) all cells were positive for the staining ('positive'); (ii) some cells were positive but the rest of the carcinoma cells were negative ('weakly positive'); and (iii) all were negative ('negative'). Statistical analysis revealed that the incidence of the metastasis to regional lymph nodes in the 'positive' cases was significantly higher than that in the 'negative' cases. Moreover, the number of the CD14 positive cells including macrophages in the Stroma adjacent to the cardnomas in the 'positive' cases was less than that in the 'negative' or 'weakly positive' cases. The expression of L-PHA-binding oligosaccharides in oral squamous cell carcinoma may be responsible for their metastatic potential to regional lymph nodes, possibly Including their ability to escape macrophage recognition. 相似文献
56.
Miura N Yamamoto M Fukutake M Ohtake N Iizuka S Ishige A Sasaki H Fukuda K Yamamoto T Hayakawa S 《International immunology》2005,17(5):513-522
Recent studies have suggested that Fas-mediated apoptosis is involved in the pathogenesis of intestinal injury. In this study, we determined the role of Fas/Fas ligand (FasL) interactions in different T cell compartments using a murine model of small intestinal injury. An intraperitoneal injection of 145-2C11 (anti-CD3) antibody into C3H/HeN, BALB/c and MRL mice induced mucosal flattening and rapid, bi-phasic intestinal epithelial cell (IEC) apoptosis, which was detected by conventional light and electron microscopy and by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling. In the first, early phase, villous apoptosis was observed up to 4 h after injection, and in the second, later phase, apoptotic crypt cells gradually accumulated for up to 24 h. The early and later phases of apoptosis were reduced in lpr/lpr and nude mice compared with those in control strains. In addition, the kinetics of Fas-mediated killer activity induced by the antibody injection were different between intestinal intraepithelial lymphocytes (IEL) and splenocytes (SPL) and seemed to correlate with the bi-phasic occurrence of the apoptosis. Finally, the transfer of intestinal IEL from euthymic to nude mice induced both phases of apoptosis, whereas SPL induced the second phase's crypt apoptosis only by the antibody injection. Together, these results suggest the involvement of Fas-mediated killer activity of thymus-derived T cells in different compartments. Namely, T cell populations in different compartments are differentially involved in the induction of IEC apoptosis and contribute to the complex pathogenesis of immune-mediated intestinal injury in which Fas/FasL interactions may play a critical role. 相似文献
57.
We evaluated the effects of the erbium:YAG laser (2.9 m wavelength) on ocular structures. Energy was successfully transmitted through a fiberoptic bundle for intraocular and extraocular applications. The wavelength was strongly absorbed by ocular tissues, producing ablations with minimal thermal damage. Our results indicated that the erbium: YAG laser may have potential uses as a photoablative tool to reshape the corneal surface and as a surgical knife. 相似文献
58.
Kazuya Kusama Mayuko Miyagawa Koichiro Ota Naoko Kuwabara Kaori Saeki Yuki Ohnishi Yasuhiro Kumaki Tomoyasu Aizawa Toyokazu Nakasone Shigemi Okamatsu Hiroaki Miyaoka Kazuhiro Tamura 《Nutrients》2021,13(1)
The androgens testosterone and dihydrotestosterone (DHT) are essential for a variety of systemic functions in mature males. Alteration of these hormones results in late-onset hypogonadism (LOH) and benign prostate hyperplasia (BPH). The fruit bodies of fungi of the genus Cordyceps have been regarded as folk medicine or health food with tonic and antifatigue effects. The extract from the fruit body of Cordyceps militaris parasitizing Samia cynthia ricini (CM) was evaluated as a novel-candidate natural product for ameliorating male andropause symptoms. To explore the effects of CM on LOH and BPH, CM was applied to rat models and cultured testicular cells and prostate cells. The concentrations of androgens in the serum and culture media were determined by ELISA. Expression of steroidogenic enzymes and androgen-related genes was evaluated by qPCR, and prostatic cell proliferation was assessed with the cell-viability assay. CM maintained the serum levels of testosterone and DHT, but inhibited testosterone-induced prostate hypertrophy. CM also increased the secretion of testosterone and DHT by primary testicular cells, with no changes in the mRNA expression of steroidogenic enzymes, but decreased the growth of prostatic cell lines. Our data suggest that CM could improve both LOH and BPH in males. 相似文献
59.
60.
Kayoko Minakata Osamu Suzuki Takeshi Kumazawa Minoru Asano Naoko Harada 《International journal of legal medicine》1990,103(8):599-607
Summary An electron spin resonance (ESR) method already in use for the quantitative analysis of paraquat was applied to the analysis of diquat in blood, serum, urine, tissue homogenates and several drinks without purification of the samples. The diquat radical produced with ascorbic acid at alkaline pH was much more stable than that produced with the commonly used sodium dithionite. Radical decay in solutions covered with n-hexane was less than 5% after 60 min over a wide range of ascorbic acid concentrations. In 0.2N NaOH solution 85% of the radicals was present even after 24h. The limit of detection was 0.3 g/ml and the required amount of sample was 0.1 ml. When both diquat and paraquat were present in a sample the diquat was first extracted with 1-butanol prior to the ESR measurement, because both species were converted to the radicals. 相似文献