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1.
Sheng Li Xue Bao ; 75(1): 69-81, 2023 Feb 25.
Article in Chinese | MEDLINE | ID: mdl-36859836

ABSTRACT

The plateau zokor (Myospalax baileyi) and plateau pika (Ochotona curzoniae) are native species unique to the Qinghai-Tibetan Plateau with successful adaptation to the hypoxic environment. In this study, the number of red blood cells, hemoglobin concentration, mean hematocrit and mean volume of red blood cells were measured in plateau zokors and plateau pikas at different altitudes. Hemoglobin subtypes of two plateau animals were identified by mass spectrometry sequencing. The forward selection sites in two animals' hemoglobin subunits were analyzed by PAML4.8 program. Homologous modeling was used to analyze the effect of forward selection sites on the affinity of hemoglobin to oxygen. The adapting strategies of plateau zokors and plateau pikas to hypoxia at different altitudes were analyzed through comparing blood parameters between the two species. The results indicated that, with increasing altitudes, plateau zokors responded to hypoxia by increasing red blood cell count and decreasing red blood cell volume, while plateau pikas took the opposite strategies to plateau zokors. In erythrocytes of plateau pikas, both adult α2ß2 and fetal α2ε2 hemoglobins were identified, while erythrocytes of plateau zokors only had adult α2ß2 hemoglobin, however the affinities and the allosteric effects of the hemoglobin of plateau zokors were significantly higher than those of plateau pikas. Mechanistically, in the α and ß subunits of hemoglobin of plateau zokors and pikas, the numbers and the sites of the positively selected amino acids as well as the side chain groups polarities and orientations of the amino acids differed significantly, which may result in the difference of the affinities to oxygen of hemoglobin between plateau zokors and pikas. In conclusion, the adaptive mechanisms to respond to hypoxia in blood properties of plateau zokors and plateau pikas are species-specific.


Subject(s)
Altitude , Lagomorpha , Animals , Amino Acids , Hemoglobins , Hypoxia
2.
Sheng Li Xue Bao ; 73(1): 51-61, 2021 Feb 25.
Article in Chinese | MEDLINE | ID: mdl-33665660

ABSTRACT

In the present study, the composition and content of pulmonary surfactant (PS) were analyzed to explore the hypoxia adaptation mechanism in plateau zokors (Myospalax baileyi) and plateau pikas (Ochotona curzoniae). 36 plateau zokors and plateau pikas were trapped alive at the Laji Mountain in Guide County, Qinghai Province (at the altitude of about 3 600 m), and 36 Sprague-Dawley (SD) rats were purchased from the experimental animal center of Lanzhou University (at the altitude of about 1 500 m). All animals were lavaged after laboratory anesthesia, the blood in lung tissues was fully washed out and the lung tissues were then taken out to obtain the bronchoalveolar lavage fluid by bronchoalveolar lavage. The composition and content of phospholipids in the PS of three different kinds of animals were analyzed by using high performance liquid chromatography; the protein composition, content and types in the PS were analyzed by G-250 Coomassie brilliant blue method, polyacrylamide gel electrophoresis (PAGE) and mass spectrometry; the dissolved oxygen in the PS solutions were determined by using dissolved oxygen electrode. The results showed that the total contents of phospholipids in the PS were successively increased among plateau zokors, plateau pikas and SD rats (P < 0.05), while the total content of proteins successively decreased (P < 0.05). There were five phospholipids identified in the PS, including linoleic palmitoylphosphatidylcholine (LPPC), dipalmitoylphosphatidylcholine (DPPC), phosphatidylglyerol (PG), phosphatidylinositol (PI) and phosphatidylserine (PSe), but the relative contents of these phospholipids were different. The relative content of LPPC was successively increased among plateau zokors, plateau pikas and SD rats (P < 0.01). The relative contents of DPPC, PG and PI in the PS of plateau zokors were significantly higher than those of plateau pikas (P < 0.01), while insignificant differences between plateau pikas and SD rats (P > 0.05). The relative content of PSe had no significant differences between plateau zokors and plateau pikas (P > 0.05), but both were significantly higher than that of SD rats (P < 0.01). The serum albumin (SA) was identified in the PS of three kinds of animals, including homologous tetramer protein containing heme, which is composed of hemoglobin ß subunit, in plateau zokors and plateau pikas. Immunoglobulin (Ig) heavy chain was found in PS of plateau zokors and SD rats. The content of Ig heavy chain in plateau zokor was significantly higher than that in SD rats (P < 0.01), and the content of protein containing heme was significantly higher than that in plateau pikas (P < 0.05). The amount of dissolved oxygen was successively decreased in the PS among plateau zokors, plateau pikas and SD rats (P < 0.01), but it was significantly higher than that in saline (P < 0.01). These results suggest that the total content of proteins in the PS of plateau zokors and plateau pikas was significantly higher, while the total content of phospholipids was significantly decreased. There were high content of homologous tetramer protein containing heme in the PS of plateau zokors and plateau pikas. The relative content of DPPC, the main component of phospholipids, was significantly increased in plateau zokors. The changes of PS component and content improve the adaptability of the two plateau animals in hypoxia environment.


Subject(s)
Lagomorpha , Pulmonary Surfactants , Altitude , Animals , Hypoxia , Rats , Rats, Sprague-Dawley
3.
Chin Med J (Engl) ; 131(23): 2776-2784, 2018 Dec 05.
Article in English | MEDLINE | ID: mdl-30511679

ABSTRACT

BACKGROUND: Disease-modifying therapy is the standard treatment for patients with multiple sclerosis (MS) in remission. The primary objective of the current analysis was to assess the efficacy and safety of two teriflunomide doses (7 mg and 14 mg) in the subgroup of Chinese patients with relapsing MS included in the TOWER study. METHODS: TOWER was a multicenter, multinational, randomized, double-blind, parallel-group (three groups), placebo-controlled study. This subgroup analysis includes 148 Chinese patients randomized to receive either teriflunomide 7 mg (n = 51), teriflunomide 14 mg (n = 43), or placebo (n = 54). RESULTS: Of the 148 patients in the intent-to-treat population, adjusted annualized relapse rates were 0.63 (95% confidence interval [CI]: 0.44, 0.92) in the placebo group, 0.48 (95% CI: 0.33, 0.70) in the teriflunomide 7 mg group, and 0.18 (95% CI: 0.09, 0.36) in the teriflunomide 14 mg group; this corresponded to a significant relative risk reduction in the teriflunomide 14 mg group versus placebo (-71.2%, P = 0.0012). Teriflunomide 14 mg also tended to reduce 12-week confirmed disability worsening by 68.1% compared with placebo (hazard ratio: 0.319, P = 0.1194). There were no differences across all treatment groups in the proportion of patients with treatment-emergent adverse events (TEAEs; 72.2% in the placebo group, 74.5% in the teriflunomide 7 mg group, and 69.8% in the teriflunomide 14 mg group); corresponding proportions for serious adverse events were 11.1%, 3.9%, and 11.6%, respectively. The most frequently reported TEAEs with teriflunomide versus placebo were neutropenia, increased alanine aminotransferase, and hair thinning. CONCLUSIONS: Teriflunomide was as effective and safe in the Chinese subpopulation as it was in the overall population of patients in the TOWER trial. Teriflunomide has the potential to meet unmet medical needs for MS patients in China. TRIAL REGISTRATION: ClinicalTrials.gov, NCT00751881; https://clinicaltrials.gov/ct2/show/NCT00751881?term=NCT00751881&rank=1.


Subject(s)
Crotonates/therapeutic use , Immunosuppressive Agents/adverse effects , Immunosuppressive Agents/therapeutic use , Multiple Sclerosis/drug therapy , Toluidines/therapeutic use , China , Crotonates/administration & dosage , Crotonates/adverse effects , Double-Blind Method , Drug Administration Schedule , Humans , Hydroxybutyrates , Immunosuppressive Agents/administration & dosage , Multicenter Studies as Topic , Multiple Sclerosis/metabolism , Nitriles , Proportional Hazards Models , Toluidines/administration & dosage , Toluidines/adverse effects
4.
J Int Med Res ; 43(5): 711-7, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26130785

ABSTRACT

OBJECTIVE: A retrospective case-control study to identify stroke-associated risk factors and quantify serum C-reactive protein in patients with ischaemic stroke, with or without intracranial and/or extracranial artery occlusion (IEAO). METHODS: Patients with ischaemic stroke and internal carotid artery occlusion (ICAO), middle cerebral artery occlusion (MCAO), ICAO + MCAO, or no IEAO (control patients) were retrospectively recruited. Data regarding stroke-associated risk factors were retrieved from medical records. High sensitivity (hs)-CRP was quantified within 3 days of hospital admission. RESULTS: Patients with ICAO (n = 89), MCAO (n = 74) and ICAO + MCAO (n = 29) had significantly higher serum hs-CRP concentrations, and were significantly more likely to have coronary heart disease, a history of stroke, and more than three stroke-associated risk factors than control patients (n = 84). CONCLUSIONS: Coronary heart disease and a history of stroke are risk factors for ischaemic stroke with IEAO. Hs-CRP may be used as a marker for IEAO.


Subject(s)
Brain Ischemia/complications , Brain Ischemia/metabolism , C-Reactive Protein/metabolism , Cerebral Arterial Diseases/metabolism , Cerebral Arteries/pathology , Stroke/complications , Stroke/metabolism , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Risk Factors
5.
Pak J Med Sci ; 29(5): 1288-9, 2013 Sep.
Article in English | MEDLINE | ID: mdl-24353740

ABSTRACT

Miller Fisher's syndrome (MFS) commonly presents in the fourth and fifth decades and are rare in people over 70 years. An 85-year-old female with no significant medical history presented with upper extremity anesthesia, ptosis, and unsteady gait. The patient had a history of hypertension and diabetes mellitus. Physical examination showed bilateral total external ophthalmoplegia, areflexia, and cerebellar ataxia. Radiological and laboratory studies were unremarkable. Lumbar puncture showed albuminocytological dissociation. The combined history, physical examination, and lumbar puncture results established a presumptive diagnosis of MFS. Intravenous immunoglobulin was given for 5 days. The patient gradually improved 10 days after the onset of symptoms. Ophthalmoplegia had fully recovered after 6 months. To the best of our knowledge, this case represented the oldest patient with MFS.

6.
Zhongguo Dang Dai Er Ke Za Zhi ; 14(11): 827-9, 2012 Nov.
Article in Chinese | MEDLINE | ID: mdl-23146728

ABSTRACT

OBJECTIVE: To study the clinical features and antimicrobial resistance of community-acquired pneumonia caused by Klebsiella pneumoniae in infants. METHODS: The clinical data of 65 infants with community-acquired pneumonia caused by Klebsiella pneumoniae between 2007 and 2011 were retrospectively studied. RESULTS: Of the 65 infants, 37 cases (57%) were aged ≤3 months, 17 cases (26%) over 4 months, 7 cases (11%) over 7 months and 4 cases (6%) between 13 and 24 months. There were no significant differences in clinical manifestations and chest X-ray features between the infants with community-acquired pneumonia caused by Klebsiella pneumoniae and those with other bacterial pneumonia. Forty strains (62%) of ESBLs-producing Klebsiella pneumoniae were detected. Klebsiella pneumoniae was 100% sensitive to imipenem, meropenem and amikacin but resistant to penicillins and cephalosporins. The resistance rates of ESBLs-producing strains to penicillins, cephalosporins, amoxicillin/clavulanic acid, ampicillin/sulbactam, compound sulfamethoxazole, gentamycin, ciprofloxacin and aztreonam were significantly higher than for non-ESBLs-producing strains. ESBLs-producing strains also showed multiple-drug resistance. CONCLUSIONS: Community-acquired pneumonia caused by Klebsiella pneumoniae is common in infants aged ≤3 months. ESBLs-producing strains are prevalent in community-acquired pneumonia caused by Klebsiella pneumoniae and demonstrate both high rates of drug resistance and multiple-drug resistance.


Subject(s)
Community-Acquired Infections/drug therapy , Klebsiella Infections/drug therapy , Klebsiella pneumoniae/drug effects , Pneumonia, Bacterial/drug therapy , Drug Resistance, Bacterial , Female , Humans , Infant , Infant, Newborn , Male
7.
Sleep Med ; 13(1): 58-63, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22137119

ABSTRACT

BACKGROUND: We performed a six-week study of pramipexole vs. a placebo in Chinese restless legs syndrome patients. METHODS: Overall, 305 enrolled patients were assigned randomly in a 2:1 ratio to the pramipexole group (N=202) and the placebo group (N=103). RESULTS: Of 287 patients in the full analysis set, the pramipexole group showed significant improvement compared with the placebo group in the change of their International Restless Legs Syndrome Study Group Rating Scale of Severity (IRLS) total score from baseline to week 6 after adjustment of centers and baseline characters (-15.87±0.66 vs. -11.35±0.92, p<0.0001) and in the proportion of patients who were "much improved" and "very much improved" when measured by Clinical Global Impressions-Improvement (81.9% vs. 54.3%, p<0.0001). At week 6, the IRLS responder rate was 73.8% (pramipexole) and 48.9% (placebo) (p<0.0001) and the patient global impression responder rate was 68.6% (pramipexole) and 43.5% (placebo) (p<0.0001). The proportion of adverse events was 62.9% in the pramipexole group and 43.7% in the placebo group, respectively. No deaths occurred. CONCLUSION: Pramipexole was effective and well-tolerated in Chinese patients with restless legs syndrome.


Subject(s)
Benzothiazoles/therapeutic use , Dopamine Agonists/therapeutic use , Restless Legs Syndrome/drug therapy , Adolescent , Adult , Aged , Benzothiazoles/adverse effects , Dopamine Agonists/adverse effects , Double-Blind Method , Female , Humans , Male , Middle Aged , Pramipexole , Treatment Outcome , Young Adult
8.
BMC Neurol ; 11: 149, 2011 Nov 29.
Article in English | MEDLINE | ID: mdl-22126669

ABSTRACT

BACKGROUND: Anti-N-methyl-D-aspartate receptor encephalitis is an increasingly common autoimmune disorder mediated by antibodies to certain subunit of the N-methyl-D-aspartate receptor. Recent literatures have described anti-thyroid and infectious serology in this encephalitis but without follow-up. CASE PRESENTATION: A 17-year-old Chinese female patient presented with psychiatric symptoms, memory deficits, behavioral problems and seizures. She then progressed through unresponsiveness, dyskinesias, autonomic instability and central hypoventilation during treatment. Her conventional blood work on admission showed high titers of IgG antibodies to thyroglobulin, thyroid peroxidase and IgM antibodies to Epstein-Barr virus viral capsid antigen. An immature ovarian teratoma was found and removal of the tumor resulted in a full recovery. The final diagnosis of anti-N-methyl-D-aspartate receptor encephalitis was made by the identification of anti-N-methyl-D-aspartate receptor antibodies in her cerebral spinal fluid. Pathology studies of the teratoma revealed N-methyl-D-aspartate receptor subunit 1 positive ectopic immature nervous tissue and Epstein-Barr virus latent infection. She was discharged with symptoms free, but titers of anti-thyroid peroxidase and anti-thyroglobulin antibodies remained elevated. One year after discharge, her serum remained positive for anti-thyroid peroxidase and anti-N-methyl-D-aspartate receptor antibodies, but negative for anti-thyroglobulin antibodies and IgM against Epstein-Barr virus viral capsid antigen. CONCLUSIONS: Persistent high titers of anti-thyroid peroxidase antibodies from admission to discharge and until one year later in this patient may suggest a propensity to autoimmunity in anti- N-methyl-D-aspartate receptor encephalitis and support the idea that neuronal and thyroid autoimmunities represent a pathogenic spectrum. Enduring anti-N-methyl-D-aspartate receptor antibodies from admission to one year follow-up but seroreversion of Epstein-Barr virus viral capsid antigen IgM may raise the important issue of elucidating the triggers and boosters of anti- N-methyl-D-aspartate receptor encephalitis.


Subject(s)
Autoimmune Diseases/virology , Encephalitis/virology , Ovarian Neoplasms/complications , Receptors, N-Methyl-D-Aspartate/immunology , Teratoma/complications , Antigens, Viral/immunology , Autoantibodies/blood , Autoantibodies/immunology , Autoantigens/immunology , Autoimmune Diseases/immunology , Capsid Proteins/immunology , Encephalitis/complications , Encephalitis/immunology , Epstein-Barr Virus Infections/blood , Epstein-Barr Virus Infections/complications , Epstein-Barr Virus Infections/immunology , Female , Fluorescent Antibody Technique , Follow-Up Studies , Herpesvirus 4, Human/immunology , Humans , Immunoglobulin G/blood , Immunoglobulin G/immunology , Immunoglobulin M/blood , Immunoglobulin M/immunology , Iodide Peroxidase/immunology , Ovarian Neoplasms/immunology , Ovarian Neoplasms/virology , Radioimmunoassay , Teratoma/immunology , Teratoma/virology , Thyroglobulin/immunology , Young Adult
9.
Zhonghua Bing Li Xue Za Zhi ; 40(3): 161-4, 2011 Mar.
Article in Chinese | MEDLINE | ID: mdl-21575385

ABSTRACT

OBJECTIVE: To study the expression of tau-related protein in spinal cord of Chinese patients with Alzheimer's disease. METHODS: Gallays-Braak stain and immunohistochemical study for tau protein (AT8) were carried out in the spinal cord tissue (T2, T8, T10, L2 and S2 segments) of 3 Chinese patients with Alzheimer's disease. Seven age-matched cases without evidence of dementia or neurologic disease were used as controls. RESULTS: Neurofibrillary tangles were identified in the neurons of anterior horn in 2 Alzheimer's disease cases but none was observed in the controls. Tau-positive axons and astroglia were detected in all Alzheimer's disease cases. Tau immunoreactivity in spinal cord of the patients correlated with that in brain tissue. CONCLUSION: The expression of tau-related protein is demonstrated in the spinal cord of Alzheimer's disease patients suggesting that axonal transport defect may play a role in the pathogenesis of Alzheimer's disease.


Subject(s)
Alzheimer Disease/metabolism , Spinal Cord/metabolism , tau Proteins/metabolism , Aged , Alzheimer Disease/pathology , Axonal Transport , Axons/metabolism , Axons/pathology , Humans , Male , Neurofibrillary Tangles/metabolism , Neurofibrillary Tangles/pathology , Phosphorylation , Spinal Cord/pathology
10.
Ying Yong Sheng Tai Xue Bao ; 22(11): 2799-806, 2011 Nov.
Article in Chinese | MEDLINE | ID: mdl-22303653

ABSTRACT

By the method of point pattern analysis, this paper studied the spatial distribution patterns of different age class individuals in the Picea schrenkiana var. tianshanica forest in middle part of Tianshan Mountain and the influence of topographic factors on the distribution patterns. It was observed that the density of different age class individuals in the forest decreased with the increasing DBH of the individuals, and except old trees which presented a random distribution at the scale of 0-12 m, the saplings and the small, medium, and big trees were in aggregative distribution at all scales. With the increase of age class, the scale at which the individuals presented the highest aggregation degree increased, whereas the aggregation intensity declined. At small scale (0-16 m), different age class individuals appeared negative association, and the greater difference the tree age, the more significant the negative association presented. Altitude had significant positive effects on the number of medium, big, and old trees but had little effects on the number of saplings and small trees. Slope grade had significant positive effects on the number of saplings and small and medium trees, significant negative effects on the number of old trees, but little effects on the number of big trees. Concavo-convex had significant negative effects on the number of saplings and small and medium trees but had little effects on the number of big and old trees.


Subject(s)
Conservation of Natural Resources , Ecosystem , Picea/growth & development , Plant Stems/anatomy & histology , Altitude , China
11.
Zhongguo Dang Dai Er Ke Za Zhi ; 12(3): 184-7, 2010 Mar.
Article in Chinese | MEDLINE | ID: mdl-20350426

ABSTRACT

OBJECTIVE: To study the distribution of pathogenic microorganisms of community acquired pneumonia (CAP) in children. METHODS: Respiratory secretion and blood specimens were collected in 1167 children with CAP within 4 hrs of admission. Mycoplasma pneumonia and Chlamydia trachomatis were detected by RT-PCR in respiratory secretion specimens. Respiratory syncytial virus (RSV-IgM) and Adenovirus (ADV-IgM) were tested using ELISA in blood samples. RESULTS: A total of 308 strains of bacteria were isolated from the respiratory tract secretions, with gram positive strains of 53.6% and gram negative strains of 46.4%. The top five bacteria strains detected were Streptococcus pneumoniae (35.1%), Escherichia coli (11.7%), Staphylococcus aureus (8.8%), Klebsiella pneumonia (6.5%) and Moraxelle catarrhalis (5.8%) in turn. Beta-lactamase and ESBLs producing strains accounted for 30.1% in the top five bacteria strains. The non-bacteria pathogens were found in 281 specimens (24.1%). Respiratory syncytial virus accounted for the most prevalent pathogen (19.3%). The mixed infection of respiratory syncytial virus and Streptococcus pneumoniae was common (35.2%). The infection rate from most of pathogenic microorganisms among children under the age of one was higher than that in children over one year old. CONCLUSIONS: Respiratory syncytial virus and Streptococcus pneumoniae are the major pathogens of CAP in children. The risk of pathogenic microorganism infections in children under the age of one is higher than that of children over one year old.


Subject(s)
Community-Acquired Infections/microbiology , Pneumonia/microbiology , Age Factors , Child , Child, Preschool , Community-Acquired Infections/etiology , Enzyme-Linked Immunosorbent Assay , Female , Humans , Infant , Infant, Newborn , Male , Respiratory Syncytial Viruses/isolation & purification , Streptococcus pneumoniae/isolation & purification
12.
Am J Med Sci ; 336(6): 519-23, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19092329

ABSTRACT

BACKGROUND: We evaluated the features of neuropathology, abnormal prion protein (PrP) molecules, and clinical data of a Chinese woman diagnosed with familiar Creutzfeldt-Jakob disease (CJD), having 7 octa-repeats inserted with codon 129 methionine homozygote in the PRNP gene. METHODS: Neuropathologic characteristics of the brain were analyzed by hemotoxylin-eosin stain and electronic microscopy. The presence of abnormal PrP in brains was detected by proteinase K and PrP molecules were evaluated by deglycosylation assay. RESULTS: Spongiform degeneration, with diffuse neuronal loss and mild astrocytic gliosis, as well as with profound degeneration of neurons and astrocytes was observed. Proteinase K-resistant PrP was deposited widely in various regions of the brain. Calculation of the glycosylation ratios of proteinase K-resistant PrP molecules identified that the monoglycosyl isomer was predominant. PrP deglycosylation tests allowed for the identification of a predominant 19-kDa PrP signal that represents a partially proteolytic C-terminal segment, a 27-kDa band that represents the full-length wild-type PrP molecule, and a 30-kDa band that probably corresponds to the full-length mutant PrP molecule. CONCLUSION: : Sporadic CJD-like neuropathologic changes and deposits of proteinase K-resistant PrP have been identified in this familiar CJD case with a 168 base pair nucleotide insertion. The clinical features differ from previously reported cases that had 7 octa-repeat insertion, but bear similarities to sporadic CJD.


Subject(s)
Creutzfeldt-Jakob Syndrome , Prions/metabolism , Cerebral Cortex/chemistry , Cerebral Cortex/pathology , Creutzfeldt-Jakob Syndrome/genetics , Creutzfeldt-Jakob Syndrome/pathology , Creutzfeldt-Jakob Syndrome/physiopathology , Fatal Outcome , Female , Humans , Prions/genetics , Repetitive Sequences, Nucleic Acid
13.
Ying Yong Sheng Tai Xue Bao ; 19(8): 1651-7, 2008 Aug.
Article in Chinese | MEDLINE | ID: mdl-18975737

ABSTRACT

An investigation was made on the standing vegetation and soil seed bank in desert riparian forest in lower reaches of Tarim River under effects of river-flooding. The results showed that the standing vegetation in non-flooded and flooded sites was composed of 14 species in 13 genera of 8 families, and 26 species in 21 genera of 10 families, respectively, and some shallow-rooted and hygrophilous species were recorded in flooded sites. The indices per unit area plant species number, vegetative coverage, plant density, and species diversity of the vegetation were all higher in flooded than in non-flooded sites. The species number of the soil seed bank in flooded sites was 19, with 5 species more than that in non-flooded sites, and the seed bank density in flooded sites was 2.94 times higher than that in non-flooded sites. The proportion of annual herbaceous species seeds in flooded sites increased by 23.07% while that of shrub species seeds decreased by 20.99%, compared with those in non-flooded sites, and the proportion of perennial herbaceous species seeds had less difference between these two sites. River-flooding increased the diversity of soil seed bank. In flooded and non-flooded sites, the co-occurrence species in seed bank and in standing vegetation were 18 and 9, with the similarity coefficients of species composition between soil seed bank and standing vegetation being 0.842 and 0.667, respectively.


Subject(s)
Desert Climate , Floods , Seeds/classification , Soil/analysis , Trees/growth & development , Biodiversity , China , Rivers
14.
Ying Yong Sheng Tai Xue Bao ; 19(12): 2611-7, 2008 Dec.
Article in Chinese | MEDLINE | ID: mdl-19288712

ABSTRACT

A field germination experiment of soil seed bank was carried out on two typical floodplains in the lower reaches of Tarim River, and a comparison was made between the soil seed banks and corresponding seedling banks on the two floodplains, aimed to assess the contribution of soil seed bank to the regeneration of damaged vegetation. The results showed that there were 12 plant species in the soil seed banks, and the life forms were mainly perennial herbs and shrubs. The soil seed banks had a density of 282.5 seeds m(-2) and 173.2 seeds x m(-2), and the seeds in top soil (0-2 cm) accounted for 76.9% and 71.0% of the total, respectively. The soil seed banks had significant effects on the seedlings species composition and density, and 84.7% and 99.4% of the seedlings on the two floodplains were emerged from corresponding soil seed banks. The similarity coefficient between soil seed bank and seedling bank of the two floodplains was 0.72 and 0.63, respectively, and there existed significant positive correlation between seedling density and soil seed bank density, illustrating that soil seed bank made important contribution to the natural regeneration of vegetation.


Subject(s)
Conservation of Natural Resources , Germination/physiology , Plant Development , Seeds/growth & development , Soil/analysis , China , Desert Climate , Ecosystem , Environmental Monitoring , Floods , Regeneration , Rivers
15.
J Environ Sci (China) ; 19(10): 1199-207, 2007.
Article in English | MEDLINE | ID: mdl-18062418

ABSTRACT

Restoration and reconstruction of the degraded Tarim River ecosystem is an important challenge. A goal of an ecological water conveyance project is to protect and restore the natural vegetation in the lower reaches of Tarim River by transferring water from Bosten Lake, through the river channel, to the lower reaches. This study describes the changes in groundwater depth during the water transfer and the respondence of riparian vegetation to alterations in groundwater levels. The results indicate that groundwater depth along the Tarim River channel has a significant spatial-temporal component. Groundwater levels closest to the river channel show the most immediate and pronounced changes as a response to water transfer while those further away respond more slowly, although the observed change appears to be longer in duration. With a rise in the groundwater level, natural vegetation responded with higher growth rates, biomass and biodiversity. These favorable changes show that it is feasible to protect and restore the degraded natural vegetation by raising the groundwater depth. Plant communities are likely to reflect the hysteresis phenomenon, requiring higher water levels to initiate and stimulate desired growth than what may be needed to maintain the plant community. Because different species have different ecologies, including different root depths and densities and water needs, their response to increasing water availability will be spatially and temporally heterogenous. The response of vegetation is also influenced by microtopography and watering style. This paper discusses strategies for the protection and restoration of the degraded vegetation in the lower reaches of the Tarim River and provides information to complement ongoing theoretical research into ecological restoration in arid or semi-arid ecosystems.


Subject(s)
Ecosystem , Rivers , Water Movements , China , Fresh Water , Geography
16.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 23(1): 49-52, 2005 Feb.
Article in Chinese | MEDLINE | ID: mdl-15804022

ABSTRACT

OBJECTIVE: The relationship between the mode of tumor invasion in the tumor-host borderline and the frequency of cervical lymph node metastasis was investigated in squamous cell carcinoma of the oral cavity. METHODS: 200 cases with histologically proven squamous cell carcinoma of the oral cavity were studied by histological method with HE stained. The mode of invasion in the tumor-host relationship was classified into five grades by Yamamoto's criteria. RESULTS: With regard to the relationship between the mode of invasion and metastasis, the more invasive the tumor tissue was, the more frequent the metastasis formed (P < 0.001). The frequency of metastasis in grades 1 and 2 was low (0 and 5.9%, respectively), The frequency of metastasis in grades 3 was moderate (14.3%), and that in grades 4c and 4d was highly rapid (63.0% and 82.9%, respectively). Single node metastases were frequent in grade 3 and grade 4c (66.7% and 58.8%, respectively), while plural node metastases were frequent in grade 4d (70.6%, P < 0.05). Moreover, the distribution of metastasized lymph nodes was focused on level 1 (41.2%) or level 1 and 2 (79.4%) in grade 4c and was dispersed from level 1 to 4 in grade 4d (P < 0.05). In the present study, the degree of differentiation did not correlate well with the frequency of metastasis. CONCLUSION: These results indicate that the more invasive the tumor cells were to the host, the more frequent the metastasis formed. The different mode of invasion would accompany with different frequency of metastasis, different number and distribution of metastasized lymph nodes.


Subject(s)
Lymphatic Metastasis , Neoplasm Invasiveness , Aged , Carcinoma, Squamous Cell , Cell Differentiation , Female , Humans , Lymph Nodes , Middle Aged , Mouth Neoplasms , Neck
17.
Zhonghua Yi Xue Za Zhi ; 84(12): 1024-8, 2004 Jun 17.
Article in Chinese | MEDLINE | ID: mdl-15312540

ABSTRACT

OBJECTIVE: To construct a fusion protein toxin DT389-hIL-13 which comprises the N-terminal 389 amino acids of diphtheria toxin (DT389) and human interlukin 13 (hIL-13), and to explore its cytotoxicity on U251 glioma cells. METHODS: The cDNA of hIL-13 gene was amplified by PCR and linked with the 3'-terminus of the gene encoding the N-terminal 389 amino acids, which correspond to the enzyme domain and transmembrane domain of diphtheria toxin. The tandem constructed gene was then inserted into an E. coli expression vector pET30a. The resulted expression vector was transformed into E. coli BL21 and induced by IPTG. The expressed protein was analyzed by SDS-PAGE and Western blot analysis. U(251) glioma cells were cultured DT389-hIl-13 was added into the culture. The cytotoxicity was determined using colorimetric MTS proliferation assay. RESULTS: The expression plasmid pET30a/DT389-hIL13 was constructed with correct sequence. The recombinant protein was successfully expressed in E. coli in manner of inclusion body and with a relative molecular weight of about 55 000, which reacted well with both anti-diphtheria toxin and anti-hIL-13 polyclonal antibody in Western blot assay. The purified recombinant chimeric toxin was found to effectively inhibit the prolifieration of glioblastoma multiforme cells bearing high affinity hIL-13 receptors, and resulted in dose-dependent relationship with 50% inhibition concentration (IC(50)) of 5 x 10(-)11mol/L. CONCLUSION: Prokaryotic expression system can be recruited to produce recombinant chimeric toxin DT389-hIL-13. The results may lay a foundation for preparing specific the agent targets for tumors overexpressing IL-13 receptor.


Subject(s)
Brain Neoplasms/pathology , Diphtheria Toxin/genetics , Glioma/pathology , Interleukin-13/genetics , Recombinant Fusion Proteins/pharmacology , Cloning, Molecular , Cytotoxicity, Immunologic , DNA, Recombinant/genetics , Diphtheria Toxin/biosynthesis , Diphtheria Toxin/pharmacology , Drug Screening Assays, Antitumor , Drug Stability , Escherichia coli/genetics , Escherichia coli/metabolism , Humans , Immunotoxins/genetics , Immunotoxins/metabolism , Immunotoxins/pharmacology , Interleukin-13/biosynthesis , Interleukin-13/pharmacology , Plasmids/genetics , Prokaryotic Cells/metabolism , Recombinant Fusion Proteins/genetics , Tumor Cells, Cultured
18.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 20(4): 315-7, 2003 Aug.
Article in Chinese | MEDLINE | ID: mdl-12903041

ABSTRACT

OBJECTIVE: To detect the difference between the Chinese Achang and Han ethnic groups in Yunnan province in the distribution of vitamin D receptor (VDR) gene start codon polymorphism. METHODS: Polymerase chain reaction-restriction fragment length polymorphism, gene sequencing and genetic analysis methods were used. A restriction fragment length polymorphism in the start codon of VDR (Fok I) gene was tested in the Achangs (n=68) and the Hans (n=92). RESULTS: The frequencies of FF, Ff and ff genotypes were found to be 18%, 35% and 47% in the Achangs, and 22%, 52% and 26% in the Hans, respectively. A significant difference was seen in the frequency distribution of VDR genotype between the Achangs and the Hans(Chi2=7.716, P=0.021). CONCLUSION: The Achang and Han ethnic groups differ in the frequency distribution of VDR gene start codon polymorphism.


Subject(s)
Codon, Initiator/genetics , Polymorphism, Genetic , Receptors, Calcitriol/genetics , China , Humans , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length
19.
Zhonghua Er Ke Za Zhi ; 41(7): 493-6, 2003 Jul.
Article in Chinese | MEDLINE | ID: mdl-14746673

ABSTRACT

OBJECTIVE: Vitamin D deficiency rickets often causes growth retardation, impaired bone formation and hypocalcemia in children. It is well known that rickets is mainly caused by vitamin D deficiency, but whether there is hereditary susceptibility of children to develop vitamin D deficiency rickets is unknown. Vitamin D receptor (VDR) gene has been used as one of genetic markers in studying the metabolic diseases of bone. The present study aimed to explore the hereditary susceptibility of children to develop rickets through studying the association between VDR gene start codon polymorphism and vitamin D deficiency rickets, METHODS: The subjects were selected from Kunming city, every subject was of Han ethnic group. The subjects were composed of two groups, the patient group consisted of 48 children with active vitamin D deficiency rickets which was diagnosed clinically and confirmed radiologically; the control group was composed of 92 normal children. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), DNA sequence analysis and genetic analysis methods were used. A restriction fragment length polymorphism in the start codon of VDR gene (FokI) was tested in both groups. RESULTS: VDR gene start codon polymorphism was tested successfully for every subject. Frequencies of FF, Ff and ff genotypes were 46%, 33% and 21% in the rickets group, and 22%, 52% and 26% in the control group, respectively. A significant difference was found in the frequency distribution of VDR genotype between two groups (chi(2) = 8.912, P = 0.012). In the patient group, Ff and ff genotypes were less common than control group, but the FF genotype was more common than control group (OR = 3.046), indicating that FF genotype may be significantly associated with vitamin D deficiency rickets. Moreover, VDR allele frequencies of FokI polymorphism also showed significant difference between the two groups (chi(2) = 5.451, P = 0.020), F alleles were more common in patient group than in control group. DNA sequence analysis identified that the start codon of F allele was mutated from ATG to ACG. CONCLUSION: There is an association between VDR gene start codon polymorphism and vitamin D deficiency rickets. This study suggested the possibility that VDR gene polymorphism might be important in determining an individual's susceptibility to development of vitamin D deficiency rickets.


Subject(s)
Codon, Initiator/genetics , Polymorphism, Genetic , Receptors, Calcitriol/genetics , Rickets/genetics , Vitamin D Deficiency/genetics , Base Sequence , Child, Preschool , DNA Mutational Analysis , Female , Gene Frequency , Genotype , Humans , Infant , Male , Point Mutation , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length
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