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1.
When 7-aminocephalosporanic acid (7-ACA) was used as a single carbon source in the enrichment culture medium for screening 7-ACA-degrading microorganisms, pink yeast colonies appeared frequently, and these were identified as Rhodotorula glutinis. These intact R. glutinis cells converted (i) 7-ACA to deacetyl-7-ACA (7-ADACA) and (ii) monochloroacetyl-7-ACA to monochloroacetyl-7-ADACA at sufficiently high levels to be of commercial interest. Acetylation of 7-ADACA to 7-ACA, the reverse reaction of hydrolysis in an organic medium with methyl acetate as an acetyl donor, was also demonstrated.  相似文献   
2.
It has been shown that mammalian neurogenesis is partly controlled by multiple basic helix–loop–helix (bHLH) genes, as inDrosophila.Recently, mouse homologs ofDrosophila atonal,a proneural gene encoding a bHLH protein required for chordotonal organ and photoreceptor development, have been characterized to obtain further insights into the molecular nature of mammalian neurogenesis. Here, to assess their potential involvement in genetic neural disorders, we have determined genetic map positions for four mouseatonal-related genes,Atoh1, Atoh2, Atoh3,andNdrf,which encode MATH-1, MATH-2, MATH-3, and NDRF, respectively. Interspecific backcross analysis indicated thatAtoh1andAtoh2were located in separate positions of Chr 6 and thatAtoh3andNdrfwere mapped to Chr 10 and Chr 11, respectively. Thus, these structurally related genes are located separately on multiple chromosomes.  相似文献   
3.
Pharbitis nil, strain Violet which had been exposed to high-intensitylight (18,000 lux at 23?C) for 7 days followed by a low-temperaturetreatment (13–14?C) for 7 days initiated flower buds evenunder continuous light, but plants given these treatments inreverse order failed to bud. Three days of high-intensity lightat 23?C was most effective in promoting the flower-inducingeffect of the subsequent low-temperature period. Six days oflow temperature following the 3-day high-intensity light periodinduced near-maximum flowering response. DCMU (5?10–6M) given during the high-intensity light period inhibited flowering,but when given during or after the low-temperature period itwas ineffective. DCMU at the same concentration given before,during or after an inductive 16-hr dark period at 26?C did notinhibit flowering. Sucrose, ATP, NADPH and some other reducingagents tested did not nullify the DCMU effect nor substitutefor the effect of high-intensity light. But, the high-intensitylight effect could be substituted, at least partly, by 5-chlorosalicylicacid, 3,4-dichlorobenzoic acid and some other benzoic acid derivatives,which are highly effective in inducing long-day flowering inthe short-day plant, Lemna paucicostata. (Received October 20, 1981; Accepted February 3, 1982)  相似文献   
4.
Summary Trypsin treatment, which is frequently used in the field of immunocytochemistry to faciliate conjugated antibody penetration through the cell membrane, was applied for the immunoradiographic demonstration of alphafetoprotein in ascites hepatoma cells using 125I-labeled anti rat alpha-fetoprotein antibody. No significant number of silver grains were detectable in the group without trypsin treatment, while numerous silver grains were recognizable in the ascites hepatoma cells after trypsin treatment. This indicates that trypsin treatment is effective for the immunoradiographic demonstration of alpha-fetoprotein and contributes to the quantitative immunoradioautographic investigation.This work was supported in part by a grant-in-aid (No. 401060) from the Ministry of Education, Science and Culture, Japan  相似文献   
5.
The preparatory motion of a defensive motion in contact sport such as basketball should be small and involve landing on both feet for strict time and motion constraints. We thus proposed the movement creating a unweighted state. Ten basketball players performed a choice reaction sidestepping task with and without the voluntary, continuous vertical fluctuation movement. The results indicated that the preparatory movement shortened the time of their sidestep initiation (301 vs. 314 ms, p = 0.011) and reaching performance (883 vs. 910 ms, p = 0.018) but did not increase their peak ground reaction force or movement velocity. The mechanism of the improvement was estimated to be the following: in the preparation phase, the vertical body fluctuation created the force fluctuation; after the direction signal, the unweighted state can shorten the time required to initiate the sidestepping (unweighted: 279 ms; weighted: 322 ms, p = 0.002); around the initiation phase, the dropping down of the body and weighted state can contribute to the reaching performance. We conducted additional experiment investigating muscle–tendon-complex dynamics and muscle activity using ultrasound device and electromyography. The result suggests that the building up of active state of muscle might explain the improvement of sidestepping performance.  相似文献   
6.
Type I IFNs are a range of host-derived molecules with adjuvant potential; they have been used for many years in the treatment of cancer and viral hepatitis. Therefore, the safety of IFNs for human use has been established. In this study, we evaluated the mucosal adjuvanticity of IFN-β administered intranasally to mice with diphtheria toxoid, and suggested a method to improve its adjuvanticity. When IFN-β alone was used as a mucosal adjuvant, no clear results were obtained. However, simultaneous administration of IFN-β and chitosan resulted in an enhancement of the specific serum immunoglobulin G (IgG) and IgA antibody responses, the mucosal IgA antibody response, and antitoxin titers. Furthermore, the intranasal administration of IFN-α alone resulted in a greater increase in antibody titer than IFN-β, and a synergistic effect with chitosan was also observed. These findings suggest that intranasal administration of chitosan and Type I IFNs may display an effective synergistic mucosal adjuvant activity.  相似文献   
7.
Insect–plant interactions are important to understanding the evolutionary mechanisms responsible for most of the diverse plant‐feeding insects. We aggregated data on sawfly–host plant associations and other resource associations from existing sources to address the following questions: (i) Is there a general correlation between host diversity and sawfly species richness? (ii) Is the pattern of host plant use consistent across sawfly lineages? and (iii) Is there a phylogenetically significant shift in species richness among sawflies? Our analysis comprised 8567 sawfly species, including 2087 species with host plant and other records. In total, there were 2126 records of host usage for sawflies, the overwhelming majority of which were sawflies using angiosperms as resources. Rosales are used by most of the species in sawfly families or subfamilies. We found that there was a strong correlation between the number of host plant orders and the species richness of sawfly families and subfamilies. To examine the points at which sawflies have experienced significant shifts in species richness, we compared sister taxon species richness. Several positive and negative shifts in species richness among sawflies were related to their range of host plant usage and specialized niche, respectively. In general, we found that most of the sawfly families and subfamilies used several orders as host plants, but mainly core eudicots, although some families or subfamilies were specialized on pteridophytes or gymnosperms.  相似文献   
8.
Endogenous fungal endophthalmitis (EFE) caused by disseminated fusariosis is a rare condition that generally has a poor outcome, even with intensive therapy. Here, we describe a case in which this type of EFE was diagnosed with vitreous sampling and was successfully treated with 25-gauge vitrectomy and antifungals, including liposomal amphotericin B and voriconazole. A 16-year-old male patient undergoing treatment for acute myeloid leukemia complained of eye pain and blurred vision in his right eye. Treatment was initiated for a vitreous opacity, possibly associated with herpetic retinitis, but the patient worsened and he was referred to us. Right-eye visual acuity was limited to light perception. We suspected endogenous endophthalmitis and performed 25-gauge vitrectomy with antibiotic perfusion of ceftazidime, vancomycin, and voriconazole. Vitreous culturing revealed the presence of Fusarium solani species complex, and enhanced computed tomography revealed disseminated fusariosis lesions in the lung, spleen, and the soft tissue of the left upper arm. The patient received antifungal treatment with liposomal amphotericin B and voriconazole, and these conditions were eliminated. Visual acuity recovered to 20/400 after additional vitrectomy for tractional retinal detachment and was maintained at this level during the 6-month follow-up period. The success of our treatment allowed the capture of optical coherence tomography images of the retina during fusarium-associated endogenous endophthalmitis and the follow-up period. Furthermore, this case showed that immediate vitrectomy for suspected EFE and intensive treatment can lead to a good clinical outcome.  相似文献   
9.
Ocular pigment epithelium (PE) cells promote the generation of T regulators (PE-induced Treg cells). Moreover, T cells exposed to PE acquire the capacity to suppress the activation of bystander T cells via TGFbeta. Membrane-bound TGFbeta on iris PE cells interacts with TGFbeta receptors on T cells, leading to the conversion of T cells to CD8(+) Treg cells via a cell contact-dependent mechanism. Conversely, soluble forms of TGFbeta produced by retinal PE cells can convert CD4(+) T cells into Treg cells in a manner that is independent of cell contact. In this study, we looked at the expression of immunoregulatory factors (TGFbeta, thrombospondins, CD59, IL-1 receptor antagonist, etc.) in PE cells as identified via an oligonucleotide microarray. Several thrombospondin-binding molecules were detected, and thus we focused subsequent analyses on thrombospondins. Via the conversion of latent TGFbeta to an active form that appears to be mediated by thrombospondin 1 (TSP-1), cultured iris PE and retinal PE cells induce a PE-induced Treg cell fate. After conversion, both ocular PE and PE-induced Treg cells express TSP-1. Regulatory T cell generation was amplified when the T cells also expressed TSP-1. In addition, PE-induced Treg cells significantly suppressed activation of bystander T cells via TSP-1. These results strongly suggest that the ability of ocular PE and PE-induced Treg cells to suppress bystander T cells depends on their capacity to produce TSP-1. Thus, intraocular TSP-1 produced by both ocular parenchymal cells and regulatory T cells is essential for immune regulation in the eye.  相似文献   
10.
In this study, we studied the effects of cortisol and cortisone on the age-related decrease in locomotion in the nematode Caenorhabditis elegans and on the tolerance to heat stress at 35 °C and to oxidative stress induced by the exposure to 0.1% H2O2. Changes in mRNA expression levels of C. elegans genes related to stress tolerance were also analyzed. Cortisol treatment restored nematode movement following heat stress and increased viability under oxidative stress, but also shortened worm lifespan. Cortisone, a cortisol precursor, also restored movement after heat stress. Additionally, cortisol treatment increased mRNA expression of the hsp-12.6 and sod-3 genes. Furthermore, cortisol treatment failed to restore movement of daf-16-deficient mutants after heat stress, whereas cortisone failed to restore the movement of dhs-30-deficient mutants after heat stress. In conclusion, the results suggested that cortisol promoted stress tolerance via DAF-16 but shortened the lifespan, whereas cortisone promoted stress tolerance via DHS-30.  相似文献   
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