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The flowering response of Dianthus gratianopolitanus Vill. 'Bath's Pink' was characterized after varying durations at vernalizing temperatures. Genetically identical clonally propagated plants were treated at 5 degrees C for 3, 6,...
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The flowering response of Dianthus gratianopolitanus Vill. 'Bath's Pink' was characterized after varying durations at vernalizing temperatures. Genetically identical clonally propagated plants were treated at 5 degrees C for 3, 6, 9, 12, or 15 weeks in Expt. I; at 0, 5, or 10 degrees C for 2,4,6, or 8 weeks in Expt. II and at 0, 5, 10, or 15 degrees C for 1, 2,4,6, or 8 weeks in Expt. III. Dianthus gratianopolitanus 'Bath's Pink' exhibited a quantitative vernalization response after treatment at 0 to 10 degrees C and did not vernalize after 8 weeks at 15 degrees C, which was the longest duration tested. Complete flowering was achieved after 4 or more weeks at 0 degrees C, 3 or more weeks at 5 C degrees, and 8 weeks at 10 degrees C. Based on time to anthesis and node number at anthesis, the flowering response was saturated after vernalization treatment at 0 degrees C for 4 or more weeks and 5 degrees C for 3 or more weeks. However, maximum flowers at anthesis were produced after 8 weeks at 0 degrees C and 6 or more weeks at 5 degrees C.. Flowering was delayed after the 8-week treatment at 10 degrees C compared with 6 or more weeks at 0 degrees C and 4 or more weeks at 5 degrees C. Based on the minimum vernalization duration required to achieve the maximum flowering response, the order of efficacy of vernalizing temperatures was 5 degrees C > 0 degrees >> 10 degrees C.
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Studies in Arabidopsis thaliana have provided us with a wealth of information about the genetic pathways that regulate plant morphogenesis. This developmental genetic treasure trove represents a fantastic resource for researchers ...
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Studies in Arabidopsis thaliana have provided us with a wealth of information about the genetic pathways that regulate plant morphogenesis. This developmental genetic treasure trove represents a fantastic resource for researchers interested in the microevolution of development. Several laboratories have begun using molecular population genetic analyses to investigate the evolutionary forces that act upon loci that regulate shoot morphogenesis. Much of this work has focused on coding sequence variation in transcription factors; however, recent studies have explored sequence variation in other types of proteins and in promoter regions. Several genes that regulate shoot development contain signatures of selective sweeps associated with positive selection or harbor putative balanced polymorphisms in coding and noncoding sequences. Other regulatory genes appear to be evolving neutrally, but have accumulated potentially deleterious replacement polymorphisms.
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PURPOSE:: In vernal keratoconjunctivitis (VKC), giant papillae are commonly observed on the superior tarsal conjunctiva. We found 3 cases of giant papillae on the inferior tarsal conjunctiva, and diagnosed them as being VKC based ...
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PURPOSE:: In vernal keratoconjunctivitis (VKC), giant papillae are commonly observed on the superior tarsal conjunctiva. We found 3 cases of giant papillae on the inferior tarsal conjunctiva, and diagnosed them as being VKC based on their clinical and histopathological features. METHODS:: Three patients with inferior tarsal giant papillae were studied. In 2 patients, the giant papillae were resected for therapeutic purposes. Immunohistochemical analysis was carried out by indirect immunofluorescent staining using anti-CD3, anti-CD20, anti-CD35 antibodies. RESULTS:: In all 3 patients, giant papilla formation was observed on the inferior lid margin. Clusters of CD20 B lymphocytes with CD35 follicular dendritic cells, and CD3 marginal zone T lymphocytes, common features of lymphoid neogenesis, were observed. In 2 patients, typical giant papillary formation was also observed on the superior tarsal conjunctiva. In all the patients, topical dexamethasone and tacrolimus treatments were found to be effective. CONCLUSIONS:: The giant papillae of VKC can occur not only on the superior tarsal conjunctiva but also on the inferior tarsal conjunctiva. The possibility of the presence of giant papillae on the inferior tarsal conjunctiva should be considered in the clinical examination of patients with VKC.
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Aim: To investigate the role of some variables, including allergy and autoimmunity, in the pathogenesis of vernal keratoconjunctivitis (VKC). The VKC is a chronic and often severe form of bilateral keratoconjunctivitis. Usually, i...
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Aim: To investigate the role of some variables, including allergy and autoimmunity, in the pathogenesis of vernal keratoconjunctivitis (VKC). The VKC is a chronic and often severe form of bilateral keratoconjunctivitis. Usually, it begins during the first decade and disappears during the end of the second decade of life. Materials and methods: 26 patients with VKC were selected. The diagnosis was performed by the ophthalmologist through a score based on ocular signs and subjective symptoms before and after administration of 1% cyclosporine A (Cy) eyedrops. Each variable was graded: 0=absent; 1=mild; 2=moderate; 3=severe. Patients with a total score 7 were included in the study. Blood samples were collected at the initial time for the determination of autoimmunity by total IgE and antinuclear antibodies (ANA). A Skin Prick Test (SPT) was performed on each patient to common inhalants and food allergens. Results: 53.8% of the children resulted atopic. The most important allergens were house dust mites and grasses. 46.1% of the patients showed total IgE >100 UI/ml and 30.8% had ANA positivity at the first determination. The photophobia occurred in 42.3% of children, most frequently with respect to other symptoms like secretion or tearing (30.8%), foreign body sensation (15.4%), itching and conjunctival hyperemia (11.5%). Conclusions: Fortunately all children improved their symptoms after Cy eyedrop therapy. Moreover, there was an elevated percentage (30.8%) of children with ANA positivity compared with the values in the general pediatric population. Despite the fact that it is a non-specific autoantibody, its high presence in a population of children with VKC may have an important role in clarifying etiopathogenesis and chronic inflammation.
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Vernal pools have been identified as unique contributors to forest biodiversity, with habitat management guidelines commonly recommending concentric zones of varying conservation intensity. However, little is known about the assoc...
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Vernal pools have been identified as unique contributors to forest biodiversity, with habitat management guidelines commonly recommending concentric zones of varying conservation intensity. However, little is known about the associated edaphic and forest structure characteristics associated with vernal pools. At Pictured Rocks National Lake-shore (Michigan, USA), we measured a stratified-random sample of 18 of 51 vernal pools to investigate soil pH, down dead wood, tree stocking, species richness, species evenness, species diversity, and species importance values within and across these zones. Within the pool zone, live tree basal area and live tree density was significantly lower and down dead wood volume was significantly higher than either the buffer or matrix zones. Nested-ANOVA and NMDS ordination indicated that importance values of under-represented species increased closer to the vernal pool. Tree diversity and richness were positively correlated with vernal pool area. These findings suggest the buffer zone serves as a transition zone between vernal pools and the surrounding forest, complementing the proposed guideline goals of reducing impacts of forest management. Vernal pools are unique forested wetlands and may provide an opportunity to maintain and enhance ecosystem complexity and resiliency.
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Woodland vernal pools occur commonly throughout northeastern North America. These pools provide preferred breeding habitat for mole salamanders (Ambystoma spp.) and wood frogs (Rana sylvatica) and support an abundant and diverse m...
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Woodland vernal pools occur commonly throughout northeastern North America. These pools provide preferred breeding habitat for mole salamanders (Ambystoma spp.) and wood frogs (Rana sylvatica) and support an abundant and diverse macroinvertebrate fauna. Vernal pool hydrology, and especially hydro-period or duration of the wet phase, affects the composition and productivity of pool fauna. The hydrology of ephemeral wetlands is dominated by local weather conditions. In this paper, I report a ten-year record of the relationships between precipitation and evapotranspiration and water-level change and hydroperiod in four typical southern New England vernal pools. Long-term average precipitation is evenly distributed throughout the year in the Northeast; potential evapotranspiration peaks in the summer months and exceeds precipitation from mid-June through mid-September. This period of water deficit causes the period of maximum vernal pool drying. Vernal pool hydroperiods were shorter and pools dried earlier in those years with larger cumulative water deficits, especially when early spring ground-water resources were below long-term means and late winter snowpack was reduced or absent. Weekly water-level change in vernal pools was significantly related to precipitation and potential evapotranspiration, with precipitation having 2—5 times greater effect than evapotranspiration. Under climate-change predictions of more episodic precipitation and increased evapotranspiration, vernal pools would dry earlier in the year and remain dry longer. These changes would adversely affect the successful reproduction of pool-breeding amphibians and isolate the remaining productive pools.
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As biennial recretohalophytes, Limonium bicolor plants need 2 years to complete their life cycle. A growth habit mutant Vernalization Requirement Loss 15 (vrl15) was obtained by ion implantation. However, the biological characteri...
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As biennial recretohalophytes, Limonium bicolor plants need 2 years to complete their life cycle. A growth habit mutant Vernalization Requirement Loss 15 (vrl15) was obtained by ion implantation. However, the biological characteristics of the mutant were unclear. In the current study, the related traits of vrl15 and some possible reasons for these traits were examined. Compared with wild type (WT), vrl15 can bolt and flower in approximately four months without vernalization. Moreover, vrl15 needed much less time to bolting and flowering than wild-type L. bicolor under different vernalization treatments. After 20 days’ vernalization, bolting vrl15 plants had 24 rosette leaves and bolting WT had 31 rosette leaves. Moreover, the pollen number per anther, the proportion of active pollen, the seed setting rate and the 1000 seed weight of vrl15 were all lower than those of WT. The soluble sugar content and soluble protein content in leaves of the vrl15 were much higher than those of WT sowed at the sametime. In addition, the GA content in the leaves of bolting vrl15 was higher than that of the non-bolting WT sowed at the same time and non-bolting vrl15, whereas the contents of ABA and BR were much lower than that of the non-bolting WT. These results indicate that to some extent the increase of GA and decrease of ABA and BR content may be involved in the growth habit and male fertility alteration of mutant vrl15 of L. bicolor.
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As biennial recretohalophytes, Limonium bicolor plants need 2 years to complete their life cycle. A growth habit mutant Vernalization Requirement Loss 15 (vrl15) was obtained by ion implantation. However, the biological characteri...
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As biennial recretohalophytes, Limonium bicolor plants need 2 years to complete their life cycle. A growth habit mutant Vernalization Requirement Loss 15 (vrl15) was obtained by ion implantation. However, the biological characteristics of the mutant were unclear. In the current study, the related traits of vrl15 and some possible reasons for these traits were examined. Compared with wild type (WT), vrl15 can bolt and flower in approximately four months without vernalization. Moreover, vrl15 needed much less time to bolting and flowering than wild-type L. bicolor under different vernalization treatments. After 20 days' vernalization, bolting vrl15 plants had 24 rosette leaves and bolting WT had 31 rosette leaves. Moreover, the pollen number per anther, the proportion of active pollen, the seed setting rate and the 1000 seed weight of vrl15 were all lower than those of WT. The soluble sugar content and soluble protein content in leaves of the vrl15 were much higher than those of WT sowed at the same time. In addition, the GA content in the leaves of bolting vrl15 was higher than that of the non-bolting WT sowed at the same time and non-bolting vrl15, whereas the contents of ABA and BR were much lower than that of the non-bolting WT. These results indicate that to some extent the increase of GA and decrease of ABA and BR content may be involved in the growth habit and male fertility alteration of mutant vrl15 of L. bicolor.
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Vernal Keratoconjunctivitis (VKC) is a severe chronic bilateral inflammation of the ocular surface characterized by seasonal exacerbations. Long-term prognosis is generally good; however, 6% develop sequelae responsible for perman...
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Vernal Keratoconjunctivitis (VKC) is a severe chronic bilateral inflammation of the ocular surface characterized by seasonal exacerbations. Long-term prognosis is generally good; however, 6% develop sequelae responsible for permanent visual impairment. Corneal involvement is almost always present, consisting of punctate keratitis, shield ulcers (3-11%) and late corneal neovascularization. In recent years, topical cyclosporine A preparations at 2% in oil or at 1% in polyvinyl alcohol, have been successfully proposed for long term VKC treatments. It has been previously proven that medical treatment is not always sufficient, especially when it is employed to treat shield ulcer plaques. In such conditions, surgery may be effective for avoiding long term complications such as amblyopia, strabismus, infections and corneal perforation. In this paper, we show the efficacy of surgical debridement by means of simple scraping associated with topical cyclosporine treatment for the management of vernal shield ulcers complicated with plaques.
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The spatial and interannual variations of dimethylsulfide (DMS) and its precursors, dissolved and particulate dimethylsulfoniopropionate (DMSP), were discussed on the basis of field observations in the surface waters of the Yellow...
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The spatial and interannual variations of dimethylsulfide (DMS) and its precursors, dissolved and particulate dimethylsulfoniopropionate (DMSP), were discussed on the basis of field observations in the surface waters of the Yellow Sea during spring 2007. Maxima of dimethylated sulfur compounds and low chlorophyll a concentrations were found in the central southern Yellow Sea, whereas low concentrations of DMS and DMSP were detected at the boundary between the northern and southern parts of the Yellow Sea. This frontal region is influenced by active water currents, air-sea interface exchanges, and biological turnover. The horizontal variations in DMS production and consumption rates showed a decreasing tendency from the coastal to offshore areas mainly due to the complicated biological features. DMS positively correlated with dissolved CH_4 and CO_2 but negatively correlated with nutrients (nitrite and phosphate). Particulate DMSP concentrations and DMS production rates positively correlated with dinoflagellate abundances but negatively correlated with diatom cell densities. DMS and DMSP concentrations, as well as DMS production and consumption rates, exhibited approximately 2.0–2.8 fold increases from 2005 to 2012. This finding was likely caused by shifts in the phytoplankton communities from diatoms to dinoflagellates and the increases in abundances of zooplankton and bacteria. Average sea-to-air DMS fluxes were estimated to be 8.12±1.24 mmol·(m~(-2)·d~(-1)), and DMS microbial consumption was approximately 1.68 times faster than the DMS sea-air exchange. These findings imply that biological consumption, relative to ventilation, is a predominant mechanism in DMS removal from the surface water.
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