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1.
BMC Pulm Med ; 23(1): 350, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37715219

ABSTRACT

BACKGROUND: Respiratory syncytial virus (RSV) infection in adults remains less recognized and understood, both socially and clinically, compared to influenza virus infection. This retrospective study aims to delineate and compare the clinical manifestations of adult RSV and influenza virus infections in the lower respiratory tract, thereby enhancing awareness of RSV lower respiratory tract infection and providing strategic insights for its prevention and treatment. METHODS: Clinical data from January 2019 to December 2020 were analyzed for 74 patients with RSV and 129 patients with influenza A/B virus lower respiratory tract infections who were admitted to respiratory or intensive care units. All patients had complete clinical data with positive IgM and negative IgG viral antibodies. Comparison parameters included onset timing, baseline data, clinical manifestations, supplementary examination results, treatment methods, and prognosis, while logistic regression was employed to ascertain the correlation of clinical features between the two patient groups. RESULTS: In comparison to the influenza group, the RSV group presented less frequently with fever at admission but exhibited a higher incidence of dyspnea and wheezing on pulmonary auscultation (P < 0.01). RSV infection was more prevalent among patients with underlying diseases, particularly chronic obstructive pulmonary disease (COPD) and demonstrated a higher probability of co-infections, most notably with Mycoplasma (P < 0.01). The RSV group had significantly higher lymphocyte counts (P < 0.01) and exhibited more incidences of pleural thickening, pulmonary fibrosis, and emphysema (P < 0.05). The use of non-invasive mechanical ventilation was more common, and hospital stays were longer in the RSV group compared to the influenza group (P < 0.05). Logistic multivariate regression analysis further revealed that age and tachypnea incidence were significantly higher in the RSV group (P < 0.05). CONCLUSION: Compared to influenza virus infection, adults with COPD are more susceptible to RSV infection. Moreover, RSV infection elevates the risk of co-infection with Mycoplasma and may lead to conditions such as pleural thickening, pulmonary fibrosis, and emphysema. The requirement for non-invasive mechanical ventilation is higher in RSV-infected patients, who also tend to have longer hospital stays. Therefore, greater awareness and preventive strategies against RSV infection are imperative.


Subject(s)
Coinfection , Emphysema , Influenza, Human , Orthomyxoviridae , Pulmonary Disease, Chronic Obstructive , Pulmonary Emphysema , Pulmonary Fibrosis , Respiratory Tract Infections , Adult , Humans , Respiratory Syncytial Viruses , Retrospective Studies , Influenza, Human/complications , Influenza, Human/epidemiology , Respiratory Tract Infections/epidemiology , Coinfection/epidemiology
2.
Front Psychol ; 13: 977663, 2022.
Article in English | MEDLINE | ID: mdl-36186376

ABSTRACT

Objective: This study explores the relationship between physical exercise and school adaptation of junior middle school students and constructs a chain intermediary model through the intermediary role of psychological resilience and sports learning motivation. Methods: Using the stratified cluster sampling method, 930 junior middle school students in Anhui Province were measured in group psychology by using the physical exercise rating scale, adolescent psychological resilience scale, physical learning motivation scale and school adaptation scale. The statistical software SPSS 23.0 and process plug-in were used for statistical processing, and the common method deviation test was carried out by Harman single-factor control method. Finally, the bootstrap sampling test method and process plug-in were used to test the significance of intermediary effect. Results: (1) The direct prediction effect of physical exercise on school adaptation is remarkable (t = 4.60, p < 0.01); (2) psychological resilience and sports learning motivation are the intermediary variables of the relationship between physical exercise and school adaptation; (3) psychological resilience and sports learning motivation play a chain mediation role in the relationship between physical exercise and school adaptation. The intermediary effect is composed of three indirect effects: physical exercise → psychological resilience → school adaptation (95% Cl: 0.004, 0.041), physical exercise → physical learning motivation → school adaptation (95% Cl:0.019, 0.065), physical exercise → psychological resilience → physical learning motivation → school adaptation (95% Cl:0.002, 0.021). Conclusions: Physical exercise can directly improve the school adaptation of junior middle school students, which can also affect junior middle school students' school adaptation indirectly through psychological resilience or sports learning motivation, and it can influence school adaptation through the chain mediation of psychological resilience and sports learning motivation.

3.
J Photochem Photobiol B ; 94(1): 54-8, 2009 Jan 09.
Article in English | MEDLINE | ID: mdl-19006675

ABSTRACT

The effect of enhanced ultraviolet-B radiation (280-315 nm) and water stress on water consumption, instantaneous water use efficiency (WUEi), season-long water use efficiency (WUEs) and leaf stable carbon isotope composition (delta13C) of three spring wheat cultivars (Triticum aestivum L.) was investigated under field conditions. The relationship between WUEi and WUEs with delta13C was analyzed. Compared with the control, enhanced UV-B or water stress alone or in combination led to lower water use, and soil drought had a stronger influence on water use than supplementary UV-B irradiance. Soil drought increased the instantaneous water use efficiency (WUEi) and UV-B radiation decreased it significantly in comparison to the control. The combination of UV-B and water stress resulted in increased/reduced or no changed WUEi, different with change. Season-long water use efficiency (WUEs) showed the same trend as observed with WUEi under the conditions of UV-B radiation and water stress, except that no significant difference between control and drought in cv. Heshangtou. WUEs under the combined conditions of UV-B and water stress, was clearly increased in every cultivar. Enhanced UV-B radiation and the combination with drought led to negative foliar stable carbon isotope composition (delta13C) and drought alone resulted in a positive value for delta13C. The relationship between foliar stable carbon isotope composition and instantaneous water use efficiency was not significant. Nevertheless, a positive correlation with delta13C against season-long water use efficiency was observed. The results indicated that delta13C can be a useable parameter for selecting a crop genotype having higher water use efficiency.


Subject(s)
Droughts , Seasons , Soil , Triticum/radiation effects , Ultraviolet Rays , Water , Triticum/metabolism , Water/metabolism
4.
J Hum Genet ; 52(7): 584-591, 2007.
Article in English | MEDLINE | ID: mdl-17579807

ABSTRACT

The Liqian people in north China are well known because of the controversial hypothesis of an ancient Roman mercenary origin. To test this hypothesis, 227 male individuals representing four Chinese populations were analyzed at 12 short tandem repeat (STR) loci and 12 single nucleotide polymorphisms (SNP). At the haplogroup levels, 77% Liqian Y chromosomes were restricted to East Asia. Principal component (PC) and multidimensional scaling (MDS) analysis suggests that the Liqians are closely related to Chinese populations, especially Han Chinese populations, whereas they greatly deviate from Central Asian and Western Eurasian populations. Further phylogenetic and admixture analysis confirmed that the Han Chinese contributed greatly to the Liqian gene pool. The Liqian and the Yugur people, regarded as kindred populations with common origins, present an underlying genetic difference in a median-joining network. Overall, a Roman mercenary origin could not be accepted as true according to paternal genetic variation, and the current Liqian population is more likely to be a subgroup of the Chinese majority Han.


Subject(s)
Chromosomes, Human, Y/genetics , Emigration and Immigration/history , Military Personnel/history , China , Haplotypes/genetics , History, Ancient , Humans , Male , Microsatellite Repeats/genetics , Phylogeny , Principal Component Analysis/history , Rome
5.
Wei Sheng Wu Xue Bao ; 46(4): 561-4, 2006 Aug.
Article in Chinese | MEDLINE | ID: mdl-17037055

ABSTRACT

Continuing depletion of the stratospheric ozone layer by atmospheric pollutants, in particular chlorofluorocarbons (CFCs), has resulted in an increasing incidence of solar UV-B (280-320 nm) at the Earth's surface. Enhanced UV-B radiation has been considered as important global environmental problem and results in important effects to mankind and the entire global ecosystem. Nitric oxide (NO) is not only a toxic molecule, one of reactive nitrogen species (RNS), but also an important redox-active signaling molecule. NO is really a double-edged sword, it can be either beneficial and activate defense responses in plants and animals or toxic, together with ROS. Besides those, NO can also act as a signal molecule and play very important roles in life of organisms. To study the effects of NO on the biological specific property of enhanced UV-B stressed Spirulina platensis, the chlorophyll-a, protein contents and biomass were investigated under enhanced UV-B radiation and its combination with different chemical treatment. The changes of chlorophyll-a, protein contents and biomass confirmed that 0.5 mmol/L sodium nitroprusside (SNP), a donor of nitric oxide (NO), could markedly alleviate the biological damage of cyanobacteria-Spirulina platensis 794 caused by enhanced ultraviolet-B. Further results proved that NO significantly increase the content of protein and proline. Meanwhile, the accumulation of reduced glutathione (GSH) in S. platensis cells were raised under normal growth condition. But exogenous NO could decrease the increasing of reduced glutathione (GSH) in enhanced UV-B stressed S. platensis cells. These results suggest that NO has protective effect and can strongly alleviate biological damage caused by UV-B stress in S. platensis 794 cells. For the first time, reported the effect of NO on the regulating ability of biological damage of S. platensis induced by enhanced UV-B. Therefore, further investigations will be necessary to inquire into the interaction and inter-correlation of signal molecules and the mechanism in cyanobacterium under enhanced UV-B stress.


Subject(s)
Cyanobacteria/drug effects , Cyanobacteria/radiation effects , Nitric Oxide/pharmacology , Ultraviolet Rays/adverse effects , Bacterial Proteins/metabolism , Chlorophyll/metabolism , Chlorophyll A , Cyanobacteria/metabolism , Gene Expression Regulation, Bacterial/drug effects , Gene Expression Regulation, Bacterial/radiation effects , Glutathione/metabolism , Nitric Oxide Donors/pharmacology , Nitroprusside/pharmacology
6.
Sci China C Life Sci ; 49(2): 141-8, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16704117

ABSTRACT

We determined and analyzed the Shigella flexneri serotype 5 (pSF5) and S. dysenteriae serotype 1 (pSD1) virulence plasmid genomes. The total length of pSF5 is 136513 bp, including 165 open reading frames (ORFs). Of these ORFs, 133 were identified and 32 of those had no significant homology to proteins with known functions. The length of pSD1 is 182545 bp, including 224 ORFs, of which we identified 181. The remaining 43 ORFs were not significantly homologous to proteins with known functions. The insertion sequence (IS) elements are 53787 bp in pSF5, and 49616 bp in pSD1, which represents 39.4% and 27.1% of the genome, respectively. There are 22 IS element types in pSF5 and pSD1, among which we report ISEc8 and ISSbo6 for the first time in the Shigella virulence plasmid. Compared to pCP301, there are a large number of deleted genes and gene inversions in both pSF5 and pSD1. The ipa-mxi-spa locus in pSF5 is completely absent, and the genes related to the O-antigen biosynthesis are partially missing. In contrast, the above genes in pSD1 are integral, with the exception of virF. The whole genome analysis of the two plasmids shows that the loss of genes related to gene invasion or regulation also obliterates the ability of pPF5 and pSD1 to bind Congo red (Crb). Whether these genes determine the Crb function requires continued investigation.


Subject(s)
Genome, Bacterial/genetics , Plasmids/genetics , Shigella/genetics , Acyltransferases/genetics , Acyltransferases/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Chromosome Mapping , Congo Red/chemistry , DNA Replication/genetics , DNA Transposable Elements/genetics , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Genes, Bacterial/genetics , Genes, Regulator/genetics , Molecular Sequence Data , Mutagenesis, Insertional , O Antigens/biosynthesis , Sequence Analysis, DNA , Shigella/chemistry , Shigella/pathogenicity , Species Specificity , Virulence/genetics
7.
Crit Rev Microbiol ; 31(2): 79-89, 2005.
Article in English | MEDLINE | ID: mdl-15986833

ABSTRACT

This article provides an overview of existing literature on the ultraviolet-B (UV-B) radiation effects on algae and cyanobacteria. We report on the effects of UV-B radiation to the growth and development, biomass, sensitivity, photosynthetic pigments, UV-B absorbing compounds, photosynthesis, protein and DNA damage, enzyme activity, nitrogen fixation and assimilation of nitrogen, protective mechanisms of algae and cyanobacteria, the accommodation of algae and cyanobacteria to environmental stress, and the effects to ecology system. Many of the studies show the dramatic effects of UV-B radiation; but typically these studies were conducted under conditions with supplemental UV-B irradiance that was higher than would ever occur outside experimental conditions or natural condition. A few of the studies reviewed used experimental conditions and supplemental UV-B irradiance that approached realism. Enhanced UV-B generally decreased chlorophyll content, whereas it increased UV-B absorbing compounds in many algae. Decrease in photosynthesis, particularly at higher UV-B doses, was due to both direct (effect on photosystem) and indirect (decrease in pigments) effects. The decreases in chlorophyll pigments and photosynthesis resulted in lower biomass. However, algae and cyanobacteria have evolved various avoidance and repair mechanisms to protect themselves against the damaging effects of UV radiation to acclimate to enhanced UV-B radiation. The review points to areas where further studies on the relationships among nitrogenase, Rubisco, antioxidase activity, signal, antioxidants, and free radicals under enhanced UV-B are needed to quantify the effects of UV-B radiation on algae and cyanobacteria. These studies are needed in order to develop dose response functions that can facilitate development of dynamic simulation models for use in UV-B and other environmental impact assessments.


Subject(s)
Cyanobacteria/radiation effects , Eukaryota/radiation effects , Ultraviolet Rays , Photosynthesis/radiation effects
9.
Cytokine ; 30(6): 378-81, 2005 Jun 21.
Article in English | MEDLINE | ID: mdl-15878285

ABSTRACT

The incidence of gastric cancer (GC) in China is among the highest in the world. In present work, 154 patients with GC and 166 healthy controls in population of north-western China were investigated to evaluate the genetic associations of IL-1B gene single nucleotide polymorphisms (SNP) and variable number tandem repeat (VNTR) polymorphisms of IL-1RN gene with increased risk of GC. The frequency of IL-1B+3954C/T was significantly higher in GC cases group (25.97%) than that in controls (4.82%) with odds ratio (OR)=6.93 (95% confidence interval [CI] 3.13-15.36); the frequencies of IL-1B-31C/T, IL-1B-31C/C and IL-1B-511C/T genotypes were also higher in GC cases group (51.95%, 23.38% and 50.65%) than those in controls (46.99%, 19.88% and 42.77%) with OR=1.48 (95% CI 0.88-2.49), OR=1.58 (95% CI 0.84-2.95) and OR=1.39 (95% CI 0.80-2.41), respectively. The results show that these SNPs of IL-1B gene are associated with significantly increased risk of GC. This is the first report that IL-1B+3954C/T heterozygote is associated with greatly increased risk of GC. The results of this study did not support the report that IL-1RN*2+ genotypes were associated with increased risk of GC in Chinese population.


Subject(s)
Interleukin-1/genetics , Interleukin-1/physiology , Polymorphism, Genetic , Stomach Neoplasms/genetics , Alleles , Case-Control Studies , China , Genotype , Heterozygote , Humans , Minisatellite Repeats , Polymorphism, Single Nucleotide , Risk
10.
J Plant Physiol ; 162(3): 317-26, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15832684

ABSTRACT

The leaves of maize seedlings were used to measure leaf biomass including leaf length, width and weight, and to examine the relationship between nitric oxide (NO) synthase activity in microsomes and cytosol to the exo- and endo-beta-glucanase activity during growth. It was found that ultraviolet-B radiation (UV-B radiation) strongly induced nitric oxide synthase (NOS) activity but caused both a decrease of leaf biomass and exo- or endo-beta-glucanase activity. In contrast, the NOS inhibitor and NO donor largely decreased the activity of NOS in non-irradiated seedlings. The inhibitor also reduced exo- and endo-beta-glucanase activity and leaf biomass while the donor increased the enzyme activity and leaf biomass under normal conditions. Alternatively, under ultraviolet-B, the additional inhibitor of NOS and NO donor appeared to compromise the effects of ultraviolet-B on glucanase activity and leaf biomass, making the relationship between NOS activity and glucanase activity negatively correlated. This suggests that the changes of NOS activity showed a positive correlation to glucanase activity and leaf biomass in the absence of ultraviolet-B, but a negative correlation to ultraviolet-B irradiation and NO donor treatment alone. It is assumed that exo- and endogenous NO is responsible for the up-regulation of regular growth and development without ultraviolet-B. Under UV-B radiation, however, it might function as a signaling molecule of ultraviolet-B inhibiting leaf growth of maize seedlings to carry out stress-signaling transduction.


Subject(s)
Nitric Oxide/pharmacology , Nitric Oxide/physiology , Nitroprusside/pharmacology , Plant Leaves/growth & development , Ultraviolet Rays , Zea mays/growth & development , Nitric Oxide Donors/pharmacology , Plant Leaves/drug effects , Plant Leaves/radiation effects , Seedlings/drug effects , Seedlings/growth & development , Seedlings/radiation effects , Zea mays/drug effects , Zea mays/radiation effects
11.
Ying Yong Sheng Tai Xue Bao ; 15(4): 697-700, 2004 Apr.
Article in Chinese | MEDLINE | ID: mdl-15334973

ABSTRACT

This paper studied the characteristics of soybean growth under the stress of Cd, UV-B radiation and their combination. The results showed that UV-B radiation gave a more pronounced inhibition on soybean growth than cadmium. Under UV-B radiation, the internode differentiation and elongation were inhibited, the internode and plant height were reduced, and the activities of SOD and POD had an apparent increase. Cd2+ could antagonize the effect of UV-B radiation on POD activity, and inhibit indole-3-acetic acid (IAA) oxidase activity. A significant decrease of POD and IAA oxidase activities in soybean was detected when exposed to combined UV-B and Cd2+, compared with UV-B radiation only. The decrease of POD and IAA oxidase activities was related to the increase of IAA contents and photosynthetic activity, which might account for the increases of biomass and plant height. Moreover, the combined stress enhanced the inhibition of root growth, and significantly decreased root length. The IAA oxidase and POD activities and photosynthesis rate might be the crucial factors determining the pattern of soybean growth under the stress of Cd2+ in combination with UV-B radiation.


Subject(s)
Cadmium/toxicity , Glycine max/growth & development , Ultraviolet Rays , Enzyme Activation/drug effects , Enzyme Activation/radiation effects , Peroxidases/metabolism , Photosynthesis/drug effects , Photosynthesis/radiation effects , Plant Leaves/drug effects , Plant Leaves/growth & development , Plant Leaves/radiation effects , Plant Roots/drug effects , Plant Roots/growth & development , Plant Roots/radiation effects , Plant Stems/drug effects , Plant Stems/growth & development , Plant Stems/radiation effects , Glycine max/drug effects , Glycine max/radiation effects , Superoxide Dismutase/metabolism
12.
Ying Yong Sheng Tai Xue Bao ; 14(8): 1322-6, 2003 Aug.
Article in Chinese | MEDLINE | ID: mdl-14655368

ABSTRACT

The effect of enhanced UV-B radiation (280-315 nm, approximating a 15% ozone layer reduction) on competitive interaction between spring wheat (Triticum aestivum) and wild oat (Avena fatua) was examined in the field. The density-dependent mortality of both wheat and wild oat did not exhibit a significant difference between control and UV-B treatments. A relatively high degree of competitive stress enhanced the effect of UV-B stress on biomass reduction. Under UV-B enhancement, the relative competitive status of wheat in terms of total biomass and aboveground biomass increased, but decreased when based upon grain production. Shifts in competitive balance occurred with significant changes in total biomass, especially when plants grew at higher densities in monocultures and mixtures. There were different effects in direction and intensity of UV-B radiation on competition balance of the other three species pairs, but in general, the effect of UV-B was in favor of monocotyledonous. The results implied that total degree of competitive stress, especially interspecific competition, might be crucial to assess the effect of UV-B enhancement on agriculture ecosystem properly.


Subject(s)
Avena/radiation effects , Ecosystem , Triticum/radiation effects , Ultraviolet Rays , Avena/growth & development , Biomass , Crops, Agricultural/radiation effects , Triticum/growth & development
13.
Photochem Photobiol ; 77(2): 219-25, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12785062

ABSTRACT

In this report, a number of physiological aspects was examined during developmental growth of maize seedling's mesocotyl. It was found that ultraviolet B (UVB) radiation was able to significantly induce nitric oxide synthase (NOS) activities and speedup the release of apparent nitric oxide (NO) of mesocotyl and that exogenous NO donor's rhizospheric treatments may mimic the responses of the mesocotyl to UVB radiation, such as the inhibition of mesocotyl elongation, the decrease in exo- and endoglucanase activities and the increase in protein content of cell wall of mesocotyl. When the seedlings were treated with N-nitro-L-arginine, an inhibitor of NOS, the mesocotyl elongation was promoted, the exo- and endoglucanase activities were raised and the protein content was reduced. However, under UVB radiation, the effects of exogenous NO on several physiological aspects of mesocotyl were similar to those of exogenous reactive oxygen species (ROS) eliminator, N-acetyl-cysteine. All the physiological changes were associated with either the exogenous NO supply or the activities of NOS in plant. Accordingly, it is assumed that reduction in mesocotyl length caused by UVB radiation was possibly achieved through modification of the chemical properties of the cell wall polysaccharides, which was induced by NO and ROS synergically mediated changes in exo- and endo-beta-D-glucanases activities in cell walls, and NO was one of the main signaling molecule of UVB radiation in inhibiting mesocotyl elongations. So NO might function as both a second messenger and an antioxidant of UVB radiation during developmental growth of the mesocotyl.


Subject(s)
Nitric Oxide/physiology , Second Messenger Systems/physiology , Ultraviolet Rays , Zea mays/growth & development
14.
Ying Yong Sheng Tai Xue Bao ; 13(7): 814-8, 2002 Jul.
Article in Chinese | MEDLINE | ID: mdl-12385209

ABSTRACT

In order to determine the response of pollen to UV-B irradiation and the cumulative effects of UV-B exposure time on pollen germination and tube growth of plants, 19 species were investigated in vitro by exposing their pollen grains to two levels of enhanced ultravioet-B(UV-BBE) (280-320 nm, 350 and 500 mW/m2 biologically effective UV-B radiation), simulating 8% and 21% stratospheric ozone depletion in Lanzhou, China (36.04 degrees N, 1550 m), and to no UV-B (control group). Compared with the control, enhanced UV-B radiation significantly inhibited pollen germination and tube growth in most species. Higher UV-B flux rate caused greater inhibitory effect than lower UV-B radiation level. Several test plants exhibited insensitivity, even stimulation of pollen germination and tube growth to UV-B. The reduction in pollen germination rate and tube growth increased with exposure time, which indicated a cumulative effect of UV-B radiation. It is concluded that changes in pollen susceptibility to UV-B would have a serious ecological consequence under natural conditions.


Subject(s)
Flowers/radiation effects , Pollen/radiation effects , Flowers/growth & development , Germination , Plants/radiation effects , Pollen/growth & development , Ultraviolet Rays
15.
Ying Yong Sheng Tai Xue Bao ; 13(3): 359-64, 2002 Mar.
Article in Chinese | MEDLINE | ID: mdl-12132172

ABSTRACT

Current research status on the effect of enhanced UV-B radiation on plants was reviewed in this paper. The main research fields involved plant growth and morphological structure, plant physiological and biochemical metabolism, plant genetic material, UV-B-absorbing compounds and some gene expression, population, and ecosystem. In addition, some issues worthy to be studied in this field in future were proposed.


Subject(s)
Ecosystem , Gene Expression Regulation, Plant/radiation effects , Plants/radiation effects , Ultraviolet Rays/adverse effects , Flavonoids/metabolism , Plants/genetics , Plants/metabolism , Population Growth
16.
Yi Chuan Xue Bao ; 29(6): 537-41, 2002 Jun.
Article in Chinese | MEDLINE | ID: mdl-12096633

ABSTRACT

The chromosomal mutation and mitosis of the wheat (Triticum aestivum, cv. 93-4736) were observed under the condition of the enhanced ultraviolet-B radiation. The results showed that the number of cells in mitosis of the UV-B treatments was 68.09% of the control, indicating that the UV-B treatment significantly inhibited division of root tip cells in wheat. Using t-test at P < or = 0.05, there was a significant difference between the control and the treatments. The enhanced UV-B significantly increased aberration frequency of chromosomes and cells (t = 9.51, n = 3, P < 0.05). Several types of chromosomal aberration such as lagging chromosomes of chromosomes bridge, fragments, nuclear aberration occurred in both of control and UV-B treatment. However, the frequency of lagging chromosome and fragments of chromosome was increased significantly by enhanced UV-B radiation (P < 0.05). Furthermore, the UV-B treatment caused several new types of chromosomal aberrations, such as three-bundle, four-bundle and six-bundle. In our opinion, these new types of chromosomal aberrations should be called 'partition-bundle division'. Under the condition of UV-B treatment, the amount of aberrations only accounted for 2.84% of the total during the interphase. In the period, nuclear abnormality appeared mainly in forms of micronucleolus and polycaryon. In the metaphase, there mainly exist fragment chromosome, which accounted for 26.67% of the total aberrations, being secondary to lagging chromosomes. The amount of chromosomal abnormality in the anaphase and telophase was the biggest, which included the types of bridge, lagging chromosomes, etc. Among the types, the lagging chromosomes were dominant, accounting for 32.84% of the total. In this study, what was especially emphasized was the UV-B induced abnormal mitosis that was first found. In the anaphase and telophase of the treated cells, chromosomes were divided into 3 bundles, 4 bundles, or 6 bundles, respectively accounting for 8.77%, 15.43%, and 8.02% of the total abnormal cells. Three-bundle division was nonsymmetrical. The number of chromosomes in each of the three bundles was not completely equal. Four-bundle division mainly symmetrized at direction of axis, the number of each of the two bundles on the same axis was basically the same, but was different from that on another axis. Four-bundle division was conducted in two patterns of division. With respect to the much more special six-bundle division, chromosomes were regularly divided into 3 groups, symmetrizing each other. As viewed from the number of chromosomes in each bundle, it was smaller than that in normal somatic cells. In the abnormal division of cells, cell plate or cell wall between the two divided bundles was not found, leading to 'multi-bundle bodies' occurrence by the end of cell division. Therefore, the abnormal division of the somatic cells should be called 'the multi-bundle division' or 'the partition bundle division'.


Subject(s)
Chromosome Aberrations , Mitosis/radiation effects , Triticum/radiation effects , Dose-Response Relationship, Radiation , Triticum/genetics , Ultraviolet Rays
17.
Photochem Photobiol ; 75(6): 680-6, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12081332

ABSTRACT

Light-grown broad bean (Vicia faba L.) seedlings were subjected to different intensities of UV-B radiation (0, 0.05, 0.15, 0.45, 0.90, 1.45 and 1.98 W m(-2)) for 7 h under photosynthetically active radiation (70 micromol m(-2) s(-1)) and then exposed to He-Ne laser (632.8 nm, 5.43 mW mm(-2)) radiation for 5 min or red light radiation for 4 h without ambient light radiation. When He-Ne laser radiated leaves were treated using lower intensity UV-B, the activities of superoxide dismutase (EC 1.15.1.1), ascorbate peroxidase (EC 1.11.1.11) and catalase (EC 1.11.1.6) improved significantly. Moreover, the UV-B-injured plants treated with laser light recovered faster from UV-B treatment because the concentration of malondialdehyde and the rate of electrolyte leakage from leaf disks reached control levels (no UV-B or laser treatment) early compared with those exposed only to ambient light or in dark conditions. Laser treatment, however, had no repair effect on seedling damage induced by higher UV-B radiation (1.45 and 1.98 W m(-2)), even with higher laser flux rates and longer laser treatment. In addition, the red light treatment had no repair effect on UV-B-induced damage. Meanwhile, the long-term physiological effect of He-Ne laser treatment on UV-B damaged plants was presented and evaluated. The results showed that the laser had a long-term positive physiological effect on the growth of UV-B-damaged plants. With the exception of the severe damage caused by higher UV-B radiation, a laser with the proper flux rate and treatment time can repair UV-B-induced damage and shorten the recovery time.


Subject(s)
Fabaceae/radiation effects , Ultraviolet Rays , Dose-Response Relationship, Radiation , Fabaceae/metabolism , Kinetics , Lasers , Malondialdehyde/analysis , Photosynthesis/radiation effects
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