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1.
Summary Conventional chemical fixation and paraffin-embedding procedures give good preservation of morphology, although the antigenicity of many proteins in the tissue sample is destroyed. On the other hand, fresh frozen sections can preserve the antigenicity, but provide poor morphological preservation. To overcome this dilemma, cryofixation and freeze drying were used on human skin tissue, applying methodology which has only been used to study lymphoid tissue. First, fresh human skin was cryofixed in liquid isopentane (–160° C) cooled by liquid nitrogen. The skin was then freeze-dried at –40° C and 10–2 atmospheric pressure for 72 h, followed by embedding in paraffin. Sections 4 m thick taken from this cryofixed, freeze-dried, and paraffin-embedded skin were stained with hematoxylin-eosin or used for immunolabeling with antibodies against basement membrane antigen, including type IV and type VII collagen, bullous pemphigoid antigen, epidermolysis bullosa acquisita antigen, and GB3 antigen. The morphological preservation of these sections was as good as that of routine formalin-fixed and paraffin-embedded skin sections. The basement membrane was clearly immunostained with all antibodies used, and the intensity of the reaction was as strong as that seen in frozen sections. Evaluation of antigen distribution in conjunction with the detailed skin structure was therefore possible in the same sections.A part of this work was presented at the 90th Annual Meeting of the Japanese Dermatological Association, Kyoto, Japan, April, 1991 相似文献
2.
The mode of inheritance of hydronephrosis was investigated by crossing inbred DDD mice having a high incidence of hydronephrosis and C57BL/6 mice having normal kidneys. In the males, incidences of hydronephrosis in F1 animals were intermediate between the two parental strains at a rate of 32.6% in (DDD x C57BL/6)F1 and 23.4% in reciprocal F1. The same tendency was observed in F2 male animals. In BCF1 males, the number of affected mice was higher in (C57BL/6 x DDD) F1 x DDD (72.4%) than in (DDD x C57BL/6)F1 x C57BL/6 (11.1%). A few affected mice were found among the females of hybrids F1, F2 and BCF1. These results suggested that hydronephrosis in the DDD strain of mice was controlled by polygenes, and that male hormones may have some effect on the occurrence of hydronephrosis. 相似文献
3.
Formation of Recombinants Between Nontransmissible Drug-Resistance Determinants and Transfer Factors 总被引:5,自引:2,他引:3 下载免费PDF全文
Susumu Mitsuhashi Mitsuo Kameda Kenji Harada Mitsue Suzuki 《Journal of bacteriology》1969,97(3):1520-1521
Noninfectious drug-resistance determinants acquired conjugal transmissibility by the formation of recombinants with transfer factors, suggesting the origin of R factors. 相似文献
4.
Somatic mosaicism of expanded CAG repeats in brains of patients with dentatorubral-pallidoluysian atrophy: cellular population-dependent dynamics of mitotic instability. 总被引:8,自引:1,他引:7 下载免费PDF全文
H. Takano O. Onodera H. Takahashi S. Igarashi M. Yamada M. Oyake T. Ikeuchi R. Koide H. Tanaka K. Iwabuchi S. Tsuji 《American journal of human genetics》1996,58(6):1212-1222
Dentatorubral-pallidoluysian atrophy (DRPLA) is an autosomal dominant neurodegenerative disease caused by unstable expansion of a CAG repeat in the DRPLA gene. We performed detailed quantitative analysis of the size and the size distribution (range) of the expanded CAG repeats in various regions of the CNS of eight autopsied patients with DRPLA. Expanded alleles (AE) showed considerable variations in size, as well as in range, depending on the region of the CNS, whereas normal alleles did not show such variations, which indicates the occurrence of somatic mosaicism of AE in the CNS. The AE in the cerebellar cortex were consistently smaller by two to five repeat units than those in the cerebellar white matter. Moreover, the AE in the cerebral cortex were smaller by one to four repeat units than those in the cerebral white matter. These results suggest that the smaller AE in the cerebellar and cerebral cortices represent those of neuronal cells. The ranges of the AE in the cerebral cortex, cerebral white matter, and cerebellar white matter showed considerable variation ranging from 9 to 23 repeat units, whereas those in the cerebellar cortex showed little variance and were approximately 7 repeat units. The ranges of the AE in the cerebral cortex, cerebral white matter, and cerebellar white matter were much broader in patients with higher ages at death than they were in patients with lower ages at death, raising the possibility that the range of AE increases with time, as the result of mitotic instability of AE. 相似文献
5.
M Miyachi H Tanaka K Yamamoto A Yoshioka K Takahashi S Onodera 《Journal of applied physiology》2001,90(6):2439-2444
The cross-sectional area (CSA) of large-conductance arteries increases in response to endurance training in humans. To determine whether training-induced changes in arterial structure are systemic in nature or, rather, are confined to the arteries supplying exercising muscles, we studied 10 young men who performed one-legged cycle training [80% of one-legged peak O2 uptake (VO2 peak)), 40 min/day, 4 days/wk] for 6 wk and detraining for another 6 wk. There were no significant differences in baseline one-legged VO2 peak) and CSA of the common femoral artery and vein (via B-mode ultrasound) between experimental and control legs. In the experimental leg, one-legged VO2 peak) increased 16% [from 3.0 +/- 0.1 to 3.4 +/- 0.1 (SE) l/min], arterial CSA increased 16% (from 84 +/- 3 to 97 +/- 5 mm2), and venous CSA increased 46% (from 56 +/- 5 to 82 +/- 5 mm2) after endurance training. These changes returned to baseline during detraining. There were no changes in one-legged VO2 peak) and arterial CSA in the control leg, whereas femoral venous CSA in the control leg significantly increased 24% (from 54 +/- 5 to 67 +/- 4 mm2) during training. Changes in femoral arterial and venous CSA in the experimental leg were positively and significantly related to corresponding changes in one-legged VO2 peak) (r = 0.86 and 0.76, respectively), whereas there were no such relations in the control leg (r = 0.10 and 0.17). When stepwise regression analysis was performed, a primary determinant of change in VO2 peak) was change in femoral arterial CSA, explaining approximately 70% of the variability. These results support the hypothesis that the regional increase in blood flow, rather than systemic factors, is associated with the training-induced arterial expansion. Femoral arterial expansion may contribute, at least in part, to improvement in efficiency of blood transport from the heart to exercising muscles and may facilitate achievement of aerobic work capacity. 相似文献
6.
Mitsue Shibata Satoshi Kikuchi Hiroshi Tanaka Masahiro Sueyoshi Hiroshi Yoshimaru Kaoru Niiyama 《Ecological Research》2009,24(1):1-9
The effects of local population density, sex morph [protogynous (PG) or protandrous (PA)], and individual tree size on the
demographic processes of seed production were investigated in a heterodichogamous maple, Acer mono Maxim. var. Marmoratum (Nichols.) Hara f. dissectum, in a temperate forest of Japan. As the distance from conspecific reproductive adults increased, the percentage of immature
seed fall and empty seeds increased significantly, indicating higher pollination success along with local population density.
Although the difference was not distinct, pollination success was affected by the local population density of the reciprocal
sex morph rather than that of both sex morphs. The trees at higher local population density sites suffered higher seed mortality
due to predation and decay, and tended to produce smaller seeds. Thus, the impacts of local population density operated both
positively and negatively on reproduction. As a factor of individual traits, tree size scarcely affected any demographic processes.
On the other hand, sex morph did affect pollination success. Trees of PG type had lower immature seed fall than those of PA
type, suggesting that the former has higher efficiency of pollen acceptance than the latter. The results on seed demography
presented here partly support previous suggestions that heterodichogamous plants exhibit reciprocal cross-pollination and
gender specialization as reproductive traits. 相似文献
7.
Maeda I Yamashiro H Yoshioka D Onodera M Ueda S Kawase M Miyasaka H Yagi K 《Applied microbiology and biotechnology》2006,70(4):397-402
A colorimetric whole-cell sensor for dimethyl sulfide (DMS) was constructed based on the in vivo conversion of intrinsic pigments
in response to the analyte. In a marine bacterium, Rhodovulum sulfidophilum, carotenoids are synthesized via the spheroidene pathway. In this pathway, demethylspheroidene, a yellow carotenoid, is converted
to spheroidene under catalysis of O-methyltransferase. Spheroidene monooxygenase (CrtA) catalyzes the terminal step of the pathway and converts spheroidene to
spheroidenone, a red carotenoid. Here, the CrtA gene in R. sulfidophilum was removed and then reintroduced downstream of the DMS dehydrogenase gene promoter. Using this whole-cell sensor, 3 μM DMS
or dimethyl sulfoxide can be detected without adding any color-forming reagent. The ratio of the red spheroidenone to total
carotenoids increased, as the DMS concentration was raised to 0.3 mM. Comparison of the signal to the background color indicated
a shift in the color coordinate from a yellow to a red hue. An intense signal was obtained with 1-day incubation at a high
cell density when sensor cells at the exponential growth phase were used. These results show that the genetically engineered
R. sulfidophilum cells can be used to monitor the quality of marine aquacultural environments by the naked eye. 相似文献
8.
Nomura M Katayama K Nishimura A Ishida Y Ohta S Komari T Miyao-Tokutomi M Tajima S Matsuoka M 《Plant molecular biology》2000,44(1):99-106
The small subunit of ribulose-bisphosphate carboxylase (Rubisco), encoded by rbcS, is essential for photosynthesis in both C3 and C4 plants, even though the cell specificity of rbcS expression is different between C3 and C4 plants. The C3 rbcS is specifically expressed in mesophyll cells, while the C4 rbcS is expressed in bundle sheath cells, and not mesophyll cells. Two chimeric genes were constructed consisting of the structural gene encoding -glucuronidase (GUS) controlled by the two promoters from maize (C4) and rice (C3) rbcS genes. These constructs were introduced into a C4 plant, maize. Both chimeric genes were specifically expressed in photosynthetic organs, such as leaf blade, but not in non-photosynthetic organs. The expressions of the genes were also regulated by light. However, the rice promoter drove the GUS activity mainly in mesophyll cells and relatively low in bundle sheath cells, while the maize rbcS promoter induced the activity specifically in bundle sheath cells. These results suggest that the rice promoter contains some cis-acting elements responding in an organ-pecific and light-inducible regulation manner in maize but does not contain element(s) for bundle sheath cell-specific expression, while the maize promoter does contain such element(s). Based on this result, we discuss the similarities and differences between the rice (C3) and maize (C4) rbcS promoter in terms of the evolution of the C4 photosynthetic gene. 相似文献
9.
Ridwansyah Iwan Yulianti Meti Apip Onodera Shin-ichi Shimizu Yuta Wibowo Hendro Fakhrudin M. 《Limnology》2020,21(3):487-498
Limnology - The Cimanuk River with a total watershed area of 4010.8 km2 flowing from the Garut Regency to Indramayu Delta is the longest in West Java Province. However, the cumulative... 相似文献
10.