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71.
Recently, we developed an intraspecies spermatogonial transplantation technique in a pelagic egg spawning marine teleost, nibe croaker Nibea mitsukurii. Nibe croaker is an ideal candidate recipient for spermatogonial transplantation since it has a short generation time and small body size. In the present study, yellowtail Seriola quinqueradiata spermatogonia were transplanted into nibe croaker larvae, and the behavior of transplanted spermatogonia in recipient gonads was observed. Three weeks post-transplantation, yellowtail spermatogonia were incorporated into the gonads of 72 out of 88 recipients. An antiproliferating cell nuclear antigen was detected in incorporated yellowtail spermatogonia, suggesting that the xenogenic germ cells were proliferating in recipient gonads. Yellowtail vasa-positive spermatogonia survived for 11 months after transplantation in the gonads of recipient fish. Thus, we showed that the microenvironment in nibe croaker gonads can support the colonization, proliferation, and survival of germ cells derived from a different taxonomic family.  相似文献   
72.
Protein-glutaminase (PG) is an enzyme that catalyzes the deamidation of protein-bound glutamine residues. We found that an enzyme labeling technique (ELT), which is a stable isotope labeling method based on transglutaminase (TGase) reaction, is applicable for PG. PG catalyzed incorporation of (15)N-labeled ammonium ions into reactive glutamine amide groups in α-lactalbumin similarly to TGase and deamidated the most reactive glutamine amide group once labeled with (15)N. Furthermore, we investigated the effect of ammonium ions on the PG activity by peptide mapping, and more reactive glutamine residues were detected than were detected by the ELT in the presence of ammonium ions. This is probably because ammonium ions are competitive inhibitors, causing decreased reactivity for glutamine residues. We propose the reaction scheme of PG in the presence of the (15)N-labeled ammonium ions and show that the ELT method with PG is useful for evaluating the activity of PG.  相似文献   
73.
A 28-month-old African hedgehog was referred to our hospital with progressive tetraparesis. On the first presentation, the hedgehog was suspected as having wobbly hedgehog syndrome (WHS) and the animal was treated with medication and rehabilitation. The animal died 22 days after onset. Pathological examination revealed that the animal was involved in astrocytoma between the medulla oblongata and the spinal cord (C1). This report indicates that a primary central nervous system tumor should be considered as one of the differential diagnoses for hedgehogs presenting with progressive paresis, together with WHS.  相似文献   
74.
In terrestrial mammals, the surface molecule CD34 is used as a marker to identify hematopoietic progenitor cells. To clarify whether CD34 expression can be used to confirm the undifferentiated state of hematopoietic-like cells isolated from the bone marrow of bottlenose dolphin, Tursiops truncates, we determined in this study the sequence of dolphin CD34 cDNA and analyzed its mRNA expression. Dolphin CD34 cDNA can be expressed as two forms, one that encodes a full-length version and a variant, truncated version of the gene. Both forms were detected in bone marrow mononuclear cells and in various tissues using RT-PCR. The truncated form was not detected in peripheral blood mononuclear cells, and neither form was detected in polymorphonuclear leukocytes. This is the first report on CD34 in marine mammals and our results suggest that dolphin CD34 may be a useful marker to identify hematopoietic progenitor cells.  相似文献   
75.
Cassiopeia A is the youngest supernova remnant known in the Milky Way and a unique laboratory for supernova physics. We present an optical spectrum of the Cassiopeia A supernova near maximum brightness, obtained from observations of a scattered light echo more than three centuries after the direct light of the explosion swept past Earth. The spectrum shows that Cassiopeia A was a type IIb supernova and originated from the collapse of the helium core of a red supergiant that had lost most of its hydrogen envelope before exploding. Our finding concludes a long-standing debate on the Cassiopeia A progenitor and provides new insight into supernova physics by linking the properties of the explosion to the wealth of knowledge about its remnant.  相似文献   
76.
The aim of the present study was to examine the effect of the somatic cell count (SCC) in milk on reproductive performance, such as pregnancy status in the prepartum period and ovarian function in the postpartum period, in dairy cows. Blood samples were collected every week from one month prepartum to parturition in order to measure the concentrations of 13,14-dihydro-15-keto-PGF (PGFM), estrone sulfate (E1S) and progesterone. Milk samples were collected three times per week in both the prepartum (for one month before the dry period) and postpartum periods (for 3 months immediately after parturition) to measure the SCC. Progesterone was also determined in the whole milk of postpartum cows to define the day of the first ovulation. In the prepartum period, the maximum SCC negatively correlated with the pregnancy period (r = –0.77), but not the calf birth weight. Positive and negative correlations were observed between the average SCC and PGFM or progesterone concentrations in plasma, respectively (r = 0.84 or –0.92, respectively), at 39 weeks of pregnancy. In the postpartum period, a correlation was observed between the day of the first ovulation and both the average and maximum SCC (r = –0.74 and –0.75, respectively), whereas days open was not related to the SCC. These results suggest that a high SCC in the prepartum period may advance parturition by increasing PGF and decreasing progesterone and that the first ovulation in the postpartum period was affected by a high SCC.  相似文献   
77.
This retrospective study of a series of 18 cases aimed to describe the clinical and pathological findings of oral tumours in rabbits, as there have been few reports detailing spontaneous oral tumours in this species. A total of 13 different tumour types were diagnosed: squamous cell carcinoma (three), ameloblastoma (two), fibrosarcoma (two), osteosarcoma (two), cementoma (one), complex odontoma (one), giant cell epulis (one), sarcoma (one), chondrosarcoma (one), trichoepithelioma (one), papilloma (one), malignant melanoma (one) and basal cell carcinoma (one). Odontogenic tumours were relatively common in this study as compared to the oral tumours typically identified in dogs and cats. The most common clinical sign in this study was feeding abnormalities. Surgical excision and radiation therapy were found to be effective in rabbits.  相似文献   
78.
79.
We first developed the method to produce inulin from sucrose using an enzyme from Bacillus sp. 217C-1. Synthesized inulin consists of a linear polymer having beta(2-1) linkages of d-fructose with one terminal glucose. The synthesized inulin has similar properties (pH and thermal stability, Maillard reaction, and in vitro fermentation) to plant-derived inulin. The marked difference is the polydispersity of the inulin chain length. Synthesized inulin with a narrow degree range of fructose polymerization shows better solubility in water than plant-derived inulin. Synthesized inulin (5%, w/w) treatment for 12 weeks reduced the elevation in body weight and serum and liver lipids in rats fed high fat- and high sucrose-supplemented diets, and blood glucose in rats fed a standard diet. Synthesized inulin (15%, w/w) significantly suppressed the elevation in blood glucose of human healthy subjects after dextrin loading. These results suggest that daily intake of synthesized inulin modulates carbohydrate and lipid metabolism.  相似文献   
80.
Mycoplasma species identification is based on biochemical, immunological, and molecular methods that require several days for accurate identification. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a novel method for identification of bacteria and has recently been introduced into the clinical microbiology laboratory as a rapid and accurate technique. This method allows a characteristic mass spectral fingerprint to be obtained from whole inactivated mycoplasmal cells. In this study, we evaluated the performance of the MALDI-TOF MS for the identification of Mycoplasma by comparison with standard sequence analysis of 16S rRNA. We developed the first database of MALDI-TOF MS profiles of Mycoplasma species, containing Mycoplasma pulmonis, M. arthritidis, and M. neurolyticum, which are the most common pathogens in mice and/or rats, and species-specific spectra were recorded. Using the database, 6 clinical isolates were identified. Six tracheal swabs from 4 mice and 2 rats were cultured on PPLO agar for 4 to 7 days, and the colonies were directly applied to analyze the protein profiles. Five strains were identified as M. pulmonis, and 1 strain from a mouse was identified as M. neurolyticum (spectral scores were >2.00); the results were consistent with the results of the 16S rRNA gene sequence analysis (homologies>97.0%). These data indicate that MALDI-TOF MS can be used as a clearly rapid, accurate, and cost-effective method for the identification of M. pulmonis isolates, and this system may represent a serious alternative for clinical laboratories to identify Mycoplasma species.  相似文献   
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