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41.
Methods of artificial insemination (AI) for indoor breeding in the Japanese monkey and the Cynomolgus monkey were investigated. For the Japanese monkey AI was carried out in six females during the winter mating season and in six females during the summer non-mating season. During the mating season, semen was inseminated near ovulation time in natural menstrual cycles. In the mating season study, three females inseminated at the uterine cavity became pregnant. Three inseminated at the cervical canal failed to become pregnant. For the non-mating season study, ovulation was induced artificially by PMSG and hCG and AI was carried out near the induced ovulation time. In the non-mating season, no animals became pregnant. Of four Cynomolgus monkeys used, pregnancy occurred in two animals inseminated near ovulation time in natural menstrual cycles. AI occurred at the uterine cavity in one and cervical canal in the other. In both species ovulation was verified by laparoscopy. Semen was collected by penile electro-stimulation then diluted to 2.5 to 5.0×107/ml with Whitten's medium. Diluted semen of 0.2l was inseminated at the uterine cavity or cervical canal. Our results indicate the usefulness of vaginal AI as a method of artificial indoor breeding.  相似文献   
42.
The ocelloid is an extraordinary eyespot organelle found only in the dinoflagellate family Warnowiaceae. It contains retina- and lens-like structures called the retinal body and the hyalosome. The ocelloid has been an evolutionary enigma because of its remarkable resemblance to the multicellular camera-type eye. To determine if the ocelloid is functionally photoreceptive, we investigated the warnowiid dinoflagellate Erythropsidinium. Here, we show that the morphology of the retinal body changed depending on different illumination conditions and the hyalosome manifests the refractile nature. Identifying a rhodopsin gene fragment in Erythropsidinium ESTs that is expressed in the retinal body by in situ hybridization, we also show that ocelloids are actually light sensitive photoreceptors. The rhodopsin gene identified is most closely related to bacterial rhodopsins. Taken together, we suggest that the ocelloid is an intracellular camera-type eye, which might be originated from endosymbiotic origin.  相似文献   
43.
A β-glucan produced by Aureobasidium pullulans (AP-PG) is consisting of a β-(1,3)-linked main chain with β-(1,6)-linked glucose side residues. Various β-glucans consisting of β-(1,3)-linked main chain including AP-PG are believed to exhibit anti-tumor activities, and actually, anti-tumor activities of AP-PG in mice have been demonstrated. In this study, we demonstrate that stimulation with AP-PG induces TRAIL expression in mouse and human macrophage-like cell lines. TRAIL is known to be a cytokine which specifically induces apoptosis in transformed cells, but not in untransformed cells. The expression of TRAIL mRNA after stimulation with AP-PG was increased in RAW264.7 cells, Mono Mac 6 cells, and macrophage-differentiated THP-1 cells. The mRNA expression of TNF-α and FasL is only weakly increased after stimulation with AP-PG. The induction activity of TRAIL by curdlan, a bacterial β-glucan, was very similar to that by AP-PG in RAW264.7 cells, but weaker in macrophage-differentiated THP-1 cells. Activation of caspases was found in HeLa cells after treatment with the supernatant of cultured medium from AP-PG-stimulated Mono Mac 6 cells, and was inhibited by the anti-TRAIL neutralizing antibody. These findings suggest that the stimulation with AP-PG effectively induces TRAIL in macrophages, and that it may be related to apoptosis induction of tumor cells.  相似文献   
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Photoacoustic tomography is a recently developed imaging modality that can provide high spatial-resolution images of hemoglobin distribution in tissues such as the breast. Because breast cancer is an angiogenesis-dependent type of malignancy, we evaluated the clinical acceptability of breast tissue images produced using our first prototype photoacoustic mammography (PAM) system in patients with known cancer. Post-excisionally, histological sections of the tumors were stained immunohistochemically (IHC) for CD31 (an endothelial marker) and carbonic anhydrase IX (CAIX) (a marker of hypoxia). Whole-slide scanning and image analyses were used to evaluate the tumor microvessel distribution pattern and to calculate the total vascular perimeter (TVP)/area for each lesion. In this clinical study, 42 lesions were primarily scanned using PAM preoperatively, three of which were reported to be benign and were excluded from statistical analysis. Images were produced for 29 out of 39 cancers (visibility rate = 74.4%) at the median depth of 26.5 (3.25–51.2) mm. Age, menopausal status, body mass index, history of neoadjuvant treatment, clinical stage and histological tumor angiogenesis markers did not seem to affect the visibility. The oxygen saturation level in all of the measured lesions was lower than in the subcutaneous counterpart vessels (Wilcoxon test, p value<0.001), as well as in the counterpart contralateral normal breast region of interest (ROI) (Wilcoxon test, p value = 0.001). Although the oxygen saturation level was not statistically significant between CAIX-positive vs. -negative cases, lesional TVP/area showed a positive correlation with the oxygen saturation level only in the group that had received therapy before PAM. In conclusion, the vascular and oxygenation data obtained by PAM have great potential for identifying functional features of breast tumors.  相似文献   
46.
Improving quality of life has been recognized as an important outcome for schizophrenia treatment, although the fundamental determinants are not well understood. In this study, we investigated the association between brain structural abnormalities and objective quality of life in schizophrenia patients. Thirty-three schizophrenia patients and 42 age-, sex-, and education-matched healthy participants underwent magnetic resonance imaging. The Quality of Life Scale was used to measure objective quality of life in schizophrenia patients. Voxel-based morphometry was performed to identify regional brain alterations that correlate with Quality of Life Scale score in the patient group. Schizophrenia patients showed gray matter reductions in the frontal, temporal, limbic, and subcortical regions. We then performed voxel-based multiple regression analysis in these regions to identify any correlations between regional gray matter volume and Quality of Life Scale scores. We found that among four subcategories of the scale, the Instrumental Role category score correlated with gray matter volume in the right anterior insula in schizophrenia patients. In addition, this correlation was shown to be mediated by negative symptoms. Our findings suggest that the neural basis of objective quality of life might differ topographically from that of subjective QOL in schizophrenia.  相似文献   
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Ueda M  Toji E  Nunobiki O  Sato N  Izuma S  Torii K  Okamoto Y  Noda S 《Human cell》2010,23(4):119-125
The clinical significance of glutathione-S-transferase GSTM1, GSTT1 and p53 codon 72 polymorphisms in cervical carcinogenesis was investigated. Germline polymorphisms of GSTM1, GSTT1 and p53 codon 72 together with human papillomavirus (HPV) types were examined in a total of 457 blood and cervical smear samples from normal healthy women and the patients with premalignant and malignant cervical lesions. The 167 patients with low-grade squamous intraepithelial lesion (LSIL), 49 with high-grade SIL (HSIL) and 83 with squamous cell carcinoma (SCC) had significantly higher frequency of high-risk HPV than 158 controls. The 49 patients with HSIL and 83 with SCC had statistically higher frequency of null GSTT1 genotype than 158 controls. There was an increased odds ratio for null GSTT1 genotype in HSIL and SCC cases compared with controls among 191 patients with high-risk HPV. The 67 cases with HPV types 16 and/or 18 had higher frequency of the GSTT1 null genotype than 186 with other types of HPV. There was no statistical difference in the polymorphic frequency of GSTM1 and p53 codon 72 genotypes between SILs and controls with or without high-risk HPV. These results suggest that GSTT1 null genotype may increase the risk of cervical cancer particularly in the cases with high-risk HPV types in a Japanese population.  相似文献   
50.
Plants can respond quickly and profoundly to changes in their environment. Several species, including Arabidopsis thaliana, are capable of differential petiole growth driven upward leaf movement (hyponastic growth) to escape from detrimental environmental conditions. Recently, we demonstrated that the leucine-rich repeat receptor-like Ser/Thr kinase gene ERECTA, explains a major effect Quantitative Trait Locus (QTL) for ethylene-induced hyponastic growth in Arabidopsis. Here, we demonstrate that ERECTA controls the hyponastic growth response to low light intensity treatment in a genetic background dependent manner. Moreover, we show that ERECTA affects low light-induced hyponastic growth independent of Phytochrome B and Cryptochrome 2 signaling, despite that these photoreceptors are positive regulators of low light-induced hyponastic growth.Key words: hyponastic growth, petiole, Arabidopsis, low light, ERECTA, differential growth, phytochrome B, cryptochrome 2Plants must adjust growth and reproduction to adverse environmental conditions. Among the strategies that plants employ to escape from unfavorable conditions is differential petiole growth-driven upward leaf movement, called hyponastic growth. Arabidopsis thaliana is able to exhibit a marked hyponastic response upon flooding, which is triggered by endogenous accumulation of the gaseous phytohormone ethylene.1 Moreover, a similar response is triggered upon low light intensity perception and in response to supra-optimal temperatures.25 By tilting the leaves to a more vertical position during submergence and shading, the plants restore contact with the atmosphere and light, respectively. The kinetics of the hyponastic growth response induced by the various stimuli is remarkably similar. This led to the hypothesis that shared functional genetic components may be employed to control hyponastic growth. Yet, at least part of the signaling cascades is parallel, as the hormonal control of the response differs between the stimuli. Low light-induced hyponastic growth for example does not require ethylene action.2 Whereas the response to heat is antagonized by this hormone.5 The abiotic stress hormone abscisic acid (ABA) antagonizes ethylene-induced hyponastic growth and stimulates heat-induced hyponastic growth.5,6 Moreover, ethylene-induced hyponasty does not involve auxin action7 whereas both heat- and low light-induced hyponasty require functional auxin signaling and transport components.2,5In our recent paper, published in The Plant Journal,8 we employed Quantitative Trait Locus (QTL) analysis to identify loci involved in the control of ethylene-induced hyponastic petiole growth. By analyzing induced mutants and by complementation analysis of naturally occurring mutant accessions, we found that the leucine-rich repeat receptor-like Ser/Thr kinase gene ERECTA (ER) is a positive regulator of ethylene-induced hyponastic growth and most likely is causal to one of the identified QTLs. In addition, we demonstrated that the ER dependency is not via ER mediated control of ethylene production or sensitivity.Since low light-induced hyponasty does not require ethylene action,2 ER may be part of the proposed shared signaling cascade leading to hyponastic growth where ethylene and low light signals meet. Therefore, we studied low light intensity-induced hyponasty in various erecta mutants. Moreover, natural occurring er mutant accessions complemented with a functional, Col-0 derived, ER allele were tested. The response of Lan-0 (Lan-0; with functional ER) to low light was indistinguishable from the response of Landsberg erecta (Ler) (Fig. 1A). However, complemented Ler (ER-Ler) showed an enhanced response compared to Ler (Fig. 1B). The response of mutant er105 was slightly attenuated compared to the wild type Columbia-0 (Fig. 1C). Mutant er104, however, showed an indistinguishable hyponastic growth phenotype to low light compared to the wild type Wassilewskija-2 (Ws-2) (Fig. 1D). Complementation of the natural occurring erecta mutant accession Vancouver-0 (Van-0) resulted in an enhanced hyponastic growth response to low light (Fig. 1E), whereas this was not the case for Hiroshima-1 (Hir-1) (Fig. 1F). Together, these data suggest that ER acts as positive regulator of low light-induced hyponastic growth and therefore may be part of the shared signaling cascade towards differential petiole growth. Yet, the effect is strongly dependent on the genetic background since the effects were not observed in every accession tested.Open in a separate windowFigure 1ERECTA involvement in low light-induced hyponasty. Effect of exposure to low light (spectral neutral reduction in light intensity from 200 to 20 µmol m−2 s−1) on the kinetics of hyponastic petiole growth in Arabidopsis thaliana. (A) mutant (circles) Ler and wild type (dashed line) Lan-0, (B) Ler and Ler complemented (ER-; squares) with the Col-0 ERECTA allele (ER-Ler), (C) er105 and Col-0 wild type, (D) er104 and Ws-2 wild type, (E) natural mutant Van-0 and Van-0 complemented with the Col-0 ER allele (ER-Van-0), (F) natural mutant Hir-1 and Hir-1 complemented with the Col-0 ER allele (ER-Hir-1). Petiole angles were measured using time-lapse photography and subsequent image analysis. Data is pairwise subtracted, which corrects for diurnal petiole movement in control conditions. For details on this procedure, growth conditions and materials, transformation protocol, treatments, data acquirement and all analyses see.1,8 Error bars represent standard errors; n ≥ 12.Phytochrome B (PhyB) and Cryptochrome 2 (Cry2) photoreceptor proteins are required for a full induction of low light-induced hyponastic growth.2 We transformed the phyb5 cry2 mutant9 (Ler genetic background) with Col-0 derived ER. This complementation did not restore the ability of phyb5 cry2 to induce hyponastic growth to neither ethylene (data not shown) nor low light conditions (Fig. 2A). Mutant phyb5 cry2 plants have a typical constitutive shade avoidance phenotype, reflected by severely elongated organs. This includes enhanced inflorescence and silique length and thin inflorescences (Fig. 2B-D). Complementation with ER resulted in a significant additional effect on these parameters (Fig. 2B-D). Together, this suggests that ER is not an integral part of PhyB nor Cry2 signaling with respect to (hyponastic) growth. Moreover, PhyB and Cry2 control of plant architecture does not require ER action. Rather, ER seems to mediate growth via genetic interaction with light-reliant growth mechanisms, instead of being downstream of photoreceptor action. Studies on the effects of ER on shade avoidance responses and various hormone responses, including cytokinin and auxin, led to the similar conclusion, suggesting a possible role for ER as a molecular hub coordinating light- and hormone-mediated plant growth.10,11 One could speculate that ER fine-tunes other (than light) environmental clues with light signaling components. A comparable conclusion was drawn previously for gibberellin (GA) reliant growth mechanisms, as er enhanced the negative effect on plant size of the short internode (shi) mutation12 and er represses the positive effect of the spindly mutation in a GA independent manner.13Open in a separate windowFigure 2Effects of ERECTA on light signaling. (A) Effect of exposure to low light (spectral neutral reduction in light intensity from 200 to 20 µmol m−2 s−1) on the kinetics of hyponastic petiole growth of Ler (dashed lines), the photoreceptor double mutant phyb5 cry2 (circles) and this mutant complemented with the Col-0 ERECTA (ER-phyb cry2; squares). For details see legend Figure 1. (B) Plant height, (C) silique length and (D) inflorescence stem thickness of the above mentioned lines. These parameters were measured when the last flower on the plant developed a silique. Plant height was measured from root/shoot junction to inflorescence top. Stem thickness was measured ∼1 cm above the root/shoot junction with a caliper and silique lengths were measured from representative pedicels in the top ∼10 cm of the main inflorescence stem. Error bars represent standard errors; n ≥ 12. Significance levels; *p < 0.05; **p < 0.01; ***p < 0.001; ns = non significant, by Students t-test.  相似文献   
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