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1.
Plant Dis ; 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627795

RESUMO

Bruguiera gymnorrhiza (Linn.) Sav. is a dominant tree species of mangrove forests in tropical coastal areas of China. This species is commonly used for the greening of tidal flats and seawalls in tropical and subtropical regions (Allen, & Duke 2000). A survey that was conducted from August to September 2020, in the mangrove national nature reserve at Zhanjiang, Guangdong Province, South China. Brown leaf spot symptoms were observed on Bruguiera gymnorrhiza and disease incidence was over 10% (200 investigated trees). Symptomatic small spots initially appeared at the middle or edges of leaves, enlarged irregularly, and developed into brown necrotic spots with dying curly edges. The color of the lesion's center changed to dark brown or gray. To identify the causative agent, twenty diseased leaves were sampled for pathogen isolation. Affected foliar tissues cut into 5 × 5 mm pieces, disinfected in 75% ethanol for 2 mins, rinsed in sterile distilled water, and then air dried under a sterilized filter paper. Leaf pieces were plated onto potato dextrose agar (PDA) in Petri dishes and then incubated at 28°C in darkness for 3-5 days. Hyphal tips of fungal colonies growing from the tissue pieces were subcultured onto fresh PDA to obtain pure single hyphae cultures. The fungal colonies were initially composed of white aerial mycelia, but turned gray after 7 days. Immature conidia were hyaline, subovoid, and aseptate while mature conidia becoming dark brown, one-septate with longitudinal stripes, the length/width ratio is 19.98 to 29.50 µm (average 24.37 µm; n = 50) × 11.99 to 14.45 µm (average 13.09 µm; n = 50). On the basis of morphological features all isolates were identified as Lasiodiplodia theobromae (Pat.) Griffon & Maubl (Alves et al. 2008). For DNA-based identification, the internal transcribed spacer (ITS) region gene and fragment of elongation factor 1-alpha (EF1-α) gene of the three isolates were amplified and sequenced following the methods described in a previous study (White et al. 1990, Carbone & Kohn 1999). The obtained sequences of ITS and EF1-α were deposited in GenBank with accession numbers OK644200 and OL345571. The BLAST results showed at least 99.60% similarity with the sequences of Lasiodiplodia theobromae (ITS, MT644474.1 [99.79%]; EF1-a, MK961975.1 [99.60%]). To fulfill Koch's postulates, PDA plugs with actively growing mycelium of the isolates were inoculated on the leaves of Bruguiera gymnorrhiza plants that were wounded by using a sterilized needle or scalpel. Inoculated leaves were covered with sterilized wet cotton, and the plants were kept at 28°C and 80% relative humidity. The inoculated plants showed leaf spot symptoms that were similar to those previously observed in the field after 1-2 days, whereas control leaves remained healthy. Lasiodiplodia theobromae was consistently isolated from inoculated leaves again. Lasiodiplodia theobromae (Botryosphaeriaceae) is a plurivorous pathogen in a wide variety of hosts, mostly prevalent in tropical and subtropical climate regions. It has been previously reported to cause brown leaf spot on Broussonetia papyrifera (Luo et al. 2020), foliar diseases on Camellia oleifera (Zhu et al. 2014) and Kadsura longipedunculata (Fan et al. 2020). To our knowledge, this is the first report of Lasiodiplodia theobromae causing brown leaf spot on Bruguiera gymnorrhiza plants in China and worldwide. Our findings will help to make management strategies for control of this disease on Bruguiera gymnorrhiza.

2.
Biology (Basel) ; 11(11)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36358312

RESUMO

To reveal the distribution and transmission pathway of Paulownia witches'-broom (PaWB) disease, which is caused by phytoplasmas related to genetic variation, and the adaptability to the hosts and environments of the pathogenic population in different geographical regions in China, in this study, we used ten housekeeping gene fragments, including rp, fusA, secY, tuf, secA, dnaK, rpoB, pyrG, gyrB, and ipt, for multilocus sequence typing (MLST). A total of 142 PaWB phytoplasma strains were collected from 18 provinces or municipalities. The results showed that the genetic diversity was comparatively higher among the PaWB phytoplasma strains, and substantially different from that of the other 16SrI subgroup strains. The number of gene variation sites for different housekeeping genes in the PaWB phytoplasma strains ranged from 1 to 14 SNPs. Among them, rpoB (1.47%) and dnaK (1.12%) had higher genetic variation, and rp (0.20%) had the least genetic variation. The tuf and rpoB genes showed the fixation of positively selected beneficial mutations in the PaWB phytoplasma populations, and all housekeeping genes except tuf followed the neutral evolutionary model. We found an absence of recombination among PaWB phytoplasma sequence types (STs) for each housekeeping gene except dnaK, and no evidence for such recombination events for concatenated sequences of PaWB phytoplasma strains. The 22 sequence types were identified among the concatenated sequences of seven housekeeping genes (rp, fusA, secY, secA, tuf, dnaK, and rpoB) from 105 representative strains. We analyzed all 22 STs by goeBURST algorithm, forming two clonal complexes (CCs) and three singletons. Among them, ST1, as the primary founder of CC1, had the widest geographical distribution, accounting for 72.38% of all strains, with a high frequency of shared sequence type. The results of phylogenetic analysis of the concatenated sequences further revealed that the 105 strains were clustered into two representative lineages of PaWB phytoplasma, with obvious geographical differentiation. The ST1 strains of highly homogeneous lineage-1 were a widespread and predominant population in diseased areas. Lineage-2 contained strains from Jiangxi, Fujian, and Shaanxi provinces, highlighting the close genetic relatedness of the strains in these regions, which was also consistent with the results of most single-gene phylogenetic analysis of each gene. We also found that the variability in the northwest China population was higher than in other geographical populations; the range of genetic differentiation between the south of the Yangtze River population and the Huang-huai-hai Plain (or southwest China) population was relatively large. The achieved diversity and evolution data, as well as the MLST technique, are helpful for epidemiological studies and guiding PaWB disease control decisions.

3.
J Int Med Res ; 50(5): 3000605221100334, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35615771

RESUMO

OBJECTIVE: Most men suffering from depression have different degrees of erectile dysfunction (ED), but the relationship between depression and ED is not clear. This study explored the effect of depression on erectile function in rats and the underlying mechanism. METHODS: The potential targets and key signaling pathways of depression and ED were predicted through bioinformatics analysis, and a depression rat model was established by inducing chronic restraint stress. Pathological changes in rat penis tissue were studied by hematoxylin and eosin staining. The serum dopamine level was quantified by an enzyme-linked immunosorbent assay. The expression of related proteins and mRNA was detected by western blotting and real-time quantitative reverse transcription-polymerase chain reaction. RESULTS: Hematoxylin and eosin staining showed pathological damage in the penile tissue of the model group rats. The serum dopamine level, dopamine receptor D2 (DRD2) and solute carrier family 6 member 3 (SLC6A3) protein levels in penile tissue, and DRD2 and SLC6A3 mRNA levels were lower in the model group than in the control group. CONCLUSION: The decrease in erectile function in the depression rat model was related to dysfunction of the dopamine system and dopaminergic synapse signaling pathway.


Assuntos
Disfunção Erétil , Animais , Depressão , Dopamina , Amarelo de Eosina-(YS)/farmacologia , Disfunção Erétil/genética , Hematoxilina/farmacologia , Humanos , Masculino , Ereção Peniana , RNA Mensageiro/genética , Ratos
4.
Plant Dis ; 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35549451

RESUMO

Taxillus chinensis (DC.) Danser is a hemiparasitic shrub, widespread in Southern China (Fu et al., 2001). T. chinensis can parasitize a wide range of species (e.g., Camellia spp., Ficus virens and Osmanthus fragrans), which obviously suppressed host growth by robbing nutrient and water through haustorium, causing considerable tree damage. During field visits to Dongguan (22°86'N, 13°97'E) and Guangzhou (23°19'N, 113°31'E), Guangdong Province, in April-July 2021, the typical phytoplasma-suspected symptom manifested as stunting, leaflet, leaf chlorosis and witches'-broom were observed in almost 36% of T. chinensis plants. Leaf samples were collected from six randomly collected plants with symptoms and six symptomless plants (Fig 1). Among them, half of T. chinensis plants parasitized on the host Elaeocarpus sylvestris, the other half on the O. fragrans. No apparent symptoms were observed on both two host plants. Total DNA was extracted from 0.5 g fresh leaf of T. chinensis plants with and without symptoms, as well as two host plants E. sylvestris and O. fragrans, using the CTAB method (Doyle et al., 1990). Nested polymerase chain reactions (PCRs) were performed on DNA extracts of all tested plants with primer pairs of P1/P7 and R16mF2/R16mR1 for 16S rRNA gene (Lee et al., 1993) and rp(v)F1/rpR1 for rp gene (Lee et al., 1998). All amplicons were obtained from symptomatic samples of T. chinensis and host plant E. sylvestris, whereas no such products resulted from DNAs of symptomless plants and O. fragrans. The amplicons were purified and sequenced by Sanger method (Rui Biotech, Guangzhou, China). The amplicon of 16S rRNA and rp genes is 1346 bp and 938 bp, respectively. BLAST comparison of the 16S rRNA (accession no. OL412744) and rp (accession no. OL473789) sequences of the T. chinensis witches'-broom phytoplasma yielded 99.6% sequence identity with those of phytoplasmas of group 16SrV jujube witches'-broom (JWB) phytoplasma (accession no. CP025121 for 16S rRNA gene and AF396941 for rp gene). The 16S rRNA gene sequence of phytoplasma in host plant E. sylvestris (accession no. OM885990) is 99.7% similarity to the 'Elaeocarpus zollingeri' yellows phytoplasma (accession no. LC257960) and 99.4% similarity to the 'Elaeocarpus sylvestris' decline phytoplasma (accession no. MW553140), but 95.8% similarity to the 16S rRNA gene of phytoplasma in T. chinensis. The virtual RFLP tool, iPhyClassifier delineated the T. chinensis phytoplasma (accession no. OL412744) to group 16SrV-B (accession no. AB052876) with the similarity coefficient 1.0 (Fig 2), and phytoplasma in E. sylvestris to group 16Sr group XXXII with the similarity coefficient 0.97. Phylogeny analyses of 16S rRNA and rp genes (MEGA version 7.0.14, USA) using reference phytoplasmas from GenBank confirmed sequencing results and placed the T. chinensis phytoplasma in group 16SrV-B (Fig. 3 and 4). In China, the 16SrV-B phytoplasma group has been reported in Amaranthus retroflexus (Yang et al., 2011), Liriodendron chinense (Li et al., 2012), Prunus salicina (Gao et al., 2020) and sweet potato (Li et al., 2021). This is the first report of a 'Ca. Phytoplasma ziziphi', 16SrV-B related phytoplasma associated with parasitic T. chinensis in China. The results of this study indicate that T. chinensis could be a vector to spread phytoplasmas 16SrV group through parasitism and this can be helpful for related research.

5.
Huan Jing Ke Xue ; 43(1): 199-209, 2022 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-34989504

RESUMO

The in-situ monitoring of stable hydrogen and oxygen isotopes (δ18O and δ2H) in precipitation is helpful to understand the processes of water phase change, mixing, and transportation. Due to the arid climate in the eastern Tarim River basin, water resources are the key factor affecting the regional sustainable development. However, the understanding of stable hydrogen and oxygen isotopes in precipitation is still limited for this region. Based on the isotope data of 103 precipitation samples collected at four stations in the eastern Tarim River basin from June 2019 to September 2020, the spatial and temporal characteristics of stable hydrogen and oxygen isotopes in precipitation were analyzed, and the connections between stable isotopes and moisture sources were discussed. The findings provide a reference for the application of environmental isotope tracers in arid areas. The results show that, ① the four sampling stations generally presented an increasing trend in precipitation stable isotopic values from north to south, and the isotopic values were higher in summer and lower in winter. The d-excess value in the study region was smaller than the national average, and the slope of the local meteoric water line exhibited a significant arid characteristic. ② There was a positive correlation between precipitation stable isotopes and air temperature in the study region, whereas a weak negative relationship was seen between d-excess and air temperature. The negative correlation occurred between δ18O and relative humidity, and the d-excess value exhibited a positive correlation with relative humidity. ③ The backward trajectory showed that the eastern Tarim River basin is mainly controlled by the westerlies paths. The proportion of air mass that comes from the middle and short distance is relatively large. The concentration weighted trajectory method showed that the farther from the precipitation sampling site, the more stable the d-excess value was. The closer to the sampling site, the more frequently the concentration changed, indicating that the d-excess value was greatly affected by the local water vapor recycling.


Assuntos
Rios , Vapor , Monitoramento Ambiental , Isótopos de Oxigênio/análise , Chuva
6.
Environ Sci Pollut Res Int ; 28(44): 63008-63016, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34218368

RESUMO

Pavements in urban area absorb more sunlight due to the canyon-like geomorphology of the urban geometry and store more heat due to the great thermal bulk properties of concrete. Heat released from pavements warms up the urban air, contributing to the urban heat island. Recently, the uses of cool pavements to reduce the pavement temperature as an urban heat island mitigation have gained momentum. Understanding the temperature and solar insolation of a pavement in an urban area is important to adopt the right cool pavement option for the right place. This study measured the temperature of paved streets in an urban mockup for 4 days in summer. It is found that east-west (EW) streets are the hottest place in an urban area, followed by the intersection, and finally the south-north (SN) street and that increasing the pavement's albedo reduces the pavement temperature effectively. The dark gray pavement in an open space is hotter than that in an urban canyon. The heat storage in the building blocks keeps the pavement warmer more than 2 °C at nighttime. The EW street is exposed to solar insolation for long hours, so it is suitable for preferentially developing reflective cool pavements.


Assuntos
Temperatura Baixa , Temperatura Alta , Cidades , Estações do Ano , Temperatura
7.
World J Clin Cases ; 9(7): 1524-1531, 2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33728296

RESUMO

BACKGROUND: Radiotherapy or chemoradiotherapy is widely used for the treatment of rectal cancer preoperatively. Although the combination of radiotherapy and chemotherapy as an established preoperative neoadjuvant therapy shows high efficacy in the treatment of rectal cancer, some patients experience a response of poor tolerance and outcomes due to the long duration radiotherapy. The study compared short duration radiotherapy plus chemotherapy vs long duration radiotherapy plus chemotherapy for rectal cancer to determine whether short duration radiation treatment should be considered to diminish complications, reduce risk of recurrence and improve survival in patients with rectal cancer. AIM: To evaluate the efficacy and safety of short duration radiotherapy combined with chemotherapy for the treatment of advanced rectal cancer. METHODS: One hundred patients with stage IIIB or higher severe rectal cancer were selected as the study subjects at The First Affiliated Hospital of Hebei North University between December 2018 and December 2019. The patients were assigned to different groups based on the treatment regimens. Fifty patients who received preoperative short durations of radiotherapy plus chemotherapy were enrolled in an observation group and fifty patients who received conventional radiotherapy and chemotherapy were enrolled in a control group. Colonoscopic biopsy was performed for all patients with pathological diagnosis of rectal cancer. The expression of tumor-related factors such as RUNX3 and Ki-67 was quantitatively analyzed using immunohistochemistry in the tissues of the patients before and after treatment. Moreover, the duration of procedure, the amount of bleeding during the operation, the anus-conserving rate, the incidence of postoperative complications (wound infection, anastomotic leakage, postoperative intestinal obstruction, etc.) and postoperative pathology were compared between the two groups. The overall survival rate, recurrence rate and distant metastasis rate were also compared through postoperative reexamination and regular follow-up. RESULTS: There was no significant difference in the positive expression rate of RUNX3 and Ki-67 between the two groups before the treatment (P > 0.05). Compared with the pretreatment value, the positive rate of RUNX3 was increased and the positive rate of Ki-67 was decreased in both groups after the treatment (all P < 0.05). The incidence of leukopenia, thrombocytopenia, neutropenia and diarrhea were higher in the observation group than in the control group (all P < 0.05). There was no significant difference in the incidence of anemia, fatigue, neurotoxicity and nausea and vomiting between the two groups (all P > 0.05). No significant difference was observed in the duration of procedure, intraoperative bleeding, the anus-conserving rate and the incidence of postoperative complications between the two groups (P > 0.05). After 1 year of follow-up, the 1-yr survival rate was 80.0% in the observation group and 68.0% in the control group, the recurrence rate was 8.0% in the observation group and 10.0% in the control group, the distant metastasis rate was 6.0% in the observation group and 8.0% in the control group difference (all P < 0.05). CONCLUSION: Short duration radiotherapy combined with chemotherapy can improve the cure rate, prolong the survival time and reduce the incidence of complications in patients with advanced rectal cancer.

8.
Ann Palliat Med ; 10(1): 312-322, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33545766

RESUMO

BACKGROUND: With the development of radiological technologies, radiotherapy has been gradually widely used in the clinic to intracranial tumours and become standardised. However, the related central nervous system disorders are still the most obvious complications after radiotherapy. This study aims to quantify the effectiveness of anlotinib, a small molecule inhibitor of multiple receptor tyrosine kinases, in mitigating acute phase of radiation-induced brain injury (RBI) in a mouse model. METHODS: The onset and progression of RBI were investigated in vivo. All mice, (except for the sham group) were irradiated at a single-fraction of 20 Gy and treated with different doses of anlotinib (0, 0.2 and 0.8 mg/kg, respectively). The expression levels of glial fibrillary acidic protein (GFAP), hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF), and phosphorylated vascular endothelial growth factor receptor-2 (p-VEGFR2) were assessed by western blot. Histological changes were identified by luxol fast blue (LFB) staining. RESULTS: The expression levels of GFAP, HIF-1α, and VEGF were downregulated following treatment with anlotinib. However, anlotinib failed to inhibit the development of demyelination. Cerebral edema [as measured by brain water content (BWC)] was also mitigated following treatment with anlotinib. CONCLUSIONS: In summary, treatment with anlotinib significantly mitigated the adverse effects of acute RBI in a dose-dependent manner by downregulating the activation of astrocytes, improving brain hypoxia, and alleviating cerebral edema.


Assuntos
Lesões Encefálicas , Quinolinas , Animais , Encéfalo/metabolismo , Indóis , Camundongos , Fator A de Crescimento do Endotélio Vascular/metabolismo
9.
Ying Yong Sheng Tai Xue Bao ; 31(11): 3814-3822, 2020 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-33300732

RESUMO

During atmospheric precipitation, the evaporation of raindrops falling from the bottom of cloud layer to the ground and passing through unsaturated air, a process was called sub-cloud secondary evaporation, which will change the isotopic composition of precipitation. Using the hydrogen and oxygen stable isotope method to understand the temporal and spatial variation of secondary evaporation effect under clouds and its causes is important to understand regional water cycle process. Based on hourly meteorological data of 187 meteorological stations in Shaanxi-Gansu-Ningxia region from March 2018 to February 2019, the spatial and temporal variations of evaporation surplus ratio (f) and precipitation excess deuterium variation (Δd) were analyzed using the improved Ste-wart model, and the relationships between f and meteorological elements and Δd were examined. The results showed that, at the hourly scale, the minimum values of f and Δd in all provinces of the region appeared in the daytime, and the maximum values appeared in the night, indicating that the secondary evaporation effect under the cloud was more obvious in the daytime. At the monthly scale, the monthly variation trend of f and Δd in each province was relatively consistent, with the minimum value appearing in the summer half year, and the maximum value appearing in the winter half year, indicating that the second evaporation effect under cloud was more significant in the summer half year. From the spatial perspective, the spatial variation of f and Δd values in the region was consistent with that at the seasonal scale. In spring, the eastern and western regions were larger while the central part was smaller. In summer, the northwest region was smaller, and other regions were larger. In autumn, it decreased from south to north. In winter, the central and southern regions were smaller, and the western and northeast regions were larger. The spatial differences of secondary evaporation effects under clouds in different seasons was significant. The slopes of the linear relationship between f and Δd in Shaanxi, Gansu and Ningxia provinces were all less than 1‰·%-1, which may be caused by the arid and semi-arid climate in this area. When air temperature was higher and the relative humidity, vapor pressure, precipitation and raindrop diameter were smaller, the value of Δd was smaller, and the secondary evaporation effect under the cloud was more obvious.


Assuntos
Monitoramento Ambiental , Chuva , China , Isótopos de Oxigênio/análise , Estações do Ano
10.
Plant Pathol J ; 36(5): 459-467, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33082730

RESUMO

Areca palm yellow leaf (AYL) disease caused by the 16SrI group phytoplasma is a serious threat to the development of the Areca palm industry in China. The 16S rRNA gene sequence was utilized to establish a rapid and efficient detection system efficient for the 16SrI-B subgroup AYL phytoplasma in China by loop-mediated isothermal amplification (LAMP). The results showed that two sets of LAMP detection primers, 16SrDNA-2 and 16SrDNA-3, were efficient for 16SrIB subgroup AYL phytoplasma in China, with positive results appearing under reaction conditions of 64oC for 40 min. The lowest detection limit for the two LAMP detection assays was the same at 200 ag/µl, namely approximately 53 copies/µl of the target fragments. Phytoplasma was detected in all AYL disease samples from Baoting, Tunchang, and Wanning counties in Hainan province using the two sets of LAMP primers 16SrDNA-2 and 16SrDNA-3, whereas no phytoplasma was detected in the negative control. The LAMP method established in this study with comparatively high sensitivity and stability, provides reliable results that could be visually detected, making it suitable for application and research in rapid diagnosis of AYL disease, detection of seedlings with the pathogen and breeding of disease-resistant Areca palm varieties.

11.
Huan Jing Ke Xue ; 41(9): 3993-4002, 2020 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124279

RESUMO

To better understand the isotope variations on a short time scale, this study focused on a long-term rainfall event with light precipitation (June 26-27) and a short-term one with heavy precipitation (July 28) in Lanzhou City in the summer of 2019. Combined with HYSPLIT model, samples collected during a continuous precipitation event every 10 min and 30 min were analyzed to explore the characteristics and mechanism of stable hydrogen and oxygen isotopes in precipitation. The results indicate that the effect of sub-cloud secondary evaporation makes the slope of the sequential meteoric water line (SMWL) smaller at the beginning of the rainfall event. Most of the continuous sampling points are distributed above the global meteoric water line (GMWL) and local meteoric water line (LMWL). Moreover, the deuterium excess is larger than the local average annual deuterium (8.13), indicating that the samples have experienced moisture recycling to a certain extent. During two consecutive days (June 26-27) of rainfall, the variations in oxygen isotope δ18O did not follow the effect of precipitation amount; the precipitation δ18O of the first day was "L" shaped, and it fluctuated the next day. On July 28, δ18O steadily decreased, and the range of δ18O exceeded 9‰. On June 26, the moisture transport path was short at the height of 500 m and on June 27 local evaporation was the main pathway. On July 28, with a relatively stable air mass, the moisture source of the entire precipitation event did not change significantly, neither did the isotope value. Therefore, for a single precipitation event on a short time scale, the difference in moisture sources is one of the reasons for isotope variations.


Assuntos
Monitoramento Ambiental , Chuva , Hidrogênio/análise , Isótopos de Oxigênio/análise , Estações do Ano , Água
12.
Ying Yong Sheng Tai Xue Bao ; 31(6): 1835-1843, 2020 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34494734

RESUMO

As plant species for riparian ecological restoration in northern China, Tamarix ramosissima and Salix matsudana play an important role in river protection, flood control, regional climate regulation, and landscape construction of riparian vegetation. Two sampling sites were selected in the riparian zones along the Lanzhou section of Yellow River, where plant xylems and potential water sources were collected. The direct comparison method, Bayesian mixture model MixSIAR and the proportional similarity index (PS index) were used to determine the proportions of water utilization for each potential water source and the relationship of two species in water utilization. The results showed that shallow soil (0-30 cm) was the main water source during growing season, with utilization ratio being 28.3% for T. ramosissima and 24.4% for S. matsudana. For T. ramosissima, river water had the lowest contribution (16.6%), and for S. matsudana, groundwater contributed the least (17.9%). In the months with low soil moisture, plants increased the utilization ratios of river water and groundwater. The PS index at the sampling site S1 and S2 was 91.0% and 87.7%, respectively. On a monthly basis, the index in May was the highest, indicating an inter-month divergence in water use relationship. At the floodplain, there were even utilization ratios for each potential water source, which is an optimal strategy to obtain water from each potential source to the maximum extent. Our results provided theoretical basis for riparian tourism development along the Lanzhou section of the Yellow River and plant water management in environment protection in the Yellow River Basin.


Assuntos
Rios , Água , Teorema de Bayes , China , Hidrogênio , Isótopos de Oxigênio
13.
Huan Jing Ke Xue ; 36(4): 1241-8, 2015 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-26164896

RESUMO

Based on stable isotopes in 409 precipitation samples provided by GNIP and meteorological records at the eight stations in Loess Plateau from January 1985 to December 2004, as well as the trajectory model of HYSPLIT 4.9, the spatial and temporal variations of d-excess and Δ18O were analyzed. The spatial distribution of secondary evaporation rate and the impact of meteorological factors on below-cloud secondary evaporation were also discussed. The result showed that: (1) During summer and winter monsoon periods, Δ18O showed an uptrend variation and d-excess showed a downtrend variation from south to north in Loess Plateau. From east to west, Δ180 showed an uptrend variation only in summer monsoon period and a downtrend variation in winter monsoon period. The value of d-excess also showed a downtrend variation. Amplitude of variation Δ18O and d-excess could indicate the routes of monsoon. (2) Secondary evaporation existed on an annual basis, and it was relatively significant during the summer monsoon period, with ranges from 1.51% to 5.88% and an average rate of 3.87%. While winter monsoon became lower, the rates ranged from 1.06% to 5.46%, and the average rate dropped to 3.03%. Monsoon had larger influence on secondary evaporation in margin area of the plateau, while the influence on the central stations was little. (3) Temperature had the highest contribution to secondary evaporation, followed by precipitation amount and water vapor pressure, and relative humidity had a small contribution. Moreover, the influence of wind speed and altitude on secondary evaporation was weak.


Assuntos
Monitoramento Ambiental , Hidrogênio/análise , Oxigênio/análise , Chuva , Altitude , Fenômenos Químicos , Clima , Isótopos de Oxigênio , Estações do Ano , Vapor , Temperatura , Água , Vento
14.
Exp Anim ; 64(1): 73-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25319758

RESUMO

In-feed Medication has been used for a long time to prevent coccidiosis, a worldwide protozoal disease in rabbits. Florfenicol (FFC) has been widely used in veterinary clinics for bacterial diseases treatment. Therefore, the use of combinations of coccidiostats with FFC in rabbits is common. In the present study, we aimed to evaluate the effect of three coccidiostats, sulfaquinoxaline (SUL), robenidine (ROB), and toltrazuril (TOL), as feed additives on the pharmacokinetic profile of FFC in rabbits. The disposition kinetics of FFC in rabbits were investigated after a single intravenous injection (25 mg/kg) in rabbits fed anticoccidial-free diets or feeds containing SUL (250 ppm), ROB (66 ppm), or TOL (2 ppm), respectively, for 20 days. Plasma FFC concentrations were determined by the high performance liquid chromatography (HPLC) method. The pharmacokinetic parameters of FFC were analyzed using a non-compartmental analysis based on the statistical moment theory. The results demonstrated that ROB feeding resulted in an obvious decrease in plasma FFC level as compared with anticoccidial-free feeding. The terminal elimination half-life (t1/2z), area under the concentration-time curve (AUC), area under the first moment curve (AUMC), and mean residence time (MRT) significantly decreased, whereas the elimination rate constant (λz) and total body clearance (CLz) obviously increased in rabbits pretreated with ROB. However, we did not find that SUL or TOL feeding had any effect on the pharmacokinetic profile of FFC. Our findings suggested that more attention should be paid to the use of FFC in rabbits supplemented with ROB.


Assuntos
Antibacterianos/farmacocinética , Coccidiostáticos/farmacologia , Robenidina/farmacologia , Sulfaquinoxalina/farmacologia , Tianfenicol/análogos & derivados , Triazinas/farmacologia , Ração Animal , Animais , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Coccidiostáticos/administração & dosagem , Interações Medicamentosas , Aditivos Alimentares , Injeções Intravenosas , Masculino , Coelhos , Robenidina/administração & dosagem , Sulfaquinoxalina/administração & dosagem , Tianfenicol/administração & dosagem , Tianfenicol/sangue , Tianfenicol/farmacocinética , Triazinas/administração & dosagem
15.
Ying Yong Sheng Tai Xue Bao ; 25(6): 1661-8, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25223021

RESUMO

In order to study the function of soil microfauna and its responses to environmental changes, we used metagenome analyses of the 18S rDNA gene region to identify differences in microfauna diversity and community structure among fifteen soil samples belonging to five different Cunninghamia lanceolate plantations. The plantations were located in Youxian County, Hunan Province in central China. The trees in these plantations were of different ages (3, 13, and 26 years) and belonged to different ecological successions (first, second, and third successions). The total dataset comprised 94922 high quality sequences with an average length of 436 bp. The dominant taxonomic groups across all samples were Chordata, Annelida, Arthropoda, Nematoda, Rotifera and Platyhelminthes with each accounting for 60.8%, 24.0%, 7.4%, 3.6%, 1.5% and 1.2% of the sequences, respectively. There were significant differences in ACE index and Shannon index among the five plantations. The lowest diversity of soil microfauna was in the 13-year old plantation of the first ecological succession. The correlation analysis showed that both ACE and available potassium concentration were negatively correlated to the Chaol index. However, there were no significant correlations between the Shannon, Simpson indices and the physical-chemical properties of soil. Overall, the Jaccard's similarity coefficient was less than 0.4 among samples at each site, and significant differences were found among plantations.


Assuntos
Biodiversidade , Cunninghamia , Florestas , Invertebrados , Solo , Animais , Anelídeos , Artrópodes , China , Nematoides , Platelmintos , Rotíferos , Árvores
16.
Oncol Lett ; 8(4): 1844-1848, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25202423

RESUMO

The optimal post-operative adjuvant treatment for completely resected gastric cancer with D2 lymphadenectomy remains controversial. The present study was a phase II trial on post-operative chemoradiotherapy in 30 patients with gastric cancer. Patients with stage II to IV (M0) gastric cancer received two cycles of chemotherapy prior to and following chemoradiotherapy. The chemotherapy consisted of a 2-h infusion of oxaliplatin (100 mg/m2) and folinic acid (100 mg/m2), which was followed by a 46-h continuous infusion of 5-fluorouracil (5-FU; 2,400 mg/m2) through a portable pump, repeated every 3 weeks. The chemoradiotherapy consisted of 45 Gy of radiotherapy for 5 weeks and 5-FU continuous infusion (350 mg/m2/day). In total, 30 patients were enrolled in this study. All patients underwent the chemoradiotherapy treatment as planned. A total of 10 (33.3%) patients relapsed; two (6.7%) locoregional relapses and mediastinum metastases, four (13.3%) peritoneal relapses, and four (13.3%) distant metastases. The three-year overall survival and disease-free survival rates were 72.7 and 65%, respectively. The toxicities of chemotherapy and radiotherapy, consisting of neutropenia, nausea and hand-foot syndrome, were observed. In conclusion, post-operative chemoradiotherapy following complete resection of gastric cancer with D2 lymphadenectomy is feasible in a significant subset of patients.

17.
Huan Jing Ke Xue ; 34(10): 3755-63, 2013 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-24364289

RESUMO

Based on the 243 daily precipitation samples and meteorological statistics at the four stations at Lanzhou city and its surrounding area (Yongdeng, Gaolan and Yuzhong) from April 2011 to March 2012, the characteristics of stable isotopes in precipitation, as well as the correlation between stable isotopes and meteorological records, were analyzed. The precipitation equation of Lanzhou city and its surrounding area were calculated through the regression analysis, and the water vapor source of the four sites was tracked by the HYSPLIT 4. 9 model, and water vapor transmission regime was established. Results showed that the precipitation equation of deltaD =7.48 delta18O + 8.13 indicated intense evaporation; delta18O value was low in winter but high in summer; The variations of observed d-excess was stable all over the year, but there was variation in different time periods; The spatial distribution showed that the weighted delta18O value decreased from the west to the east; The linear relationships between delta18O and temperature was positive correlation, but the linear relationships between delta18O and precipitation was negative correlation; The seasonal variations of delta18O indicated that westerly water vapor, local moisture and summer monsoon all had influence on this region in a large scale, but the westerly water vapor played a dominant role. However, the impact of monsoon moisture had a seasonal limitation, mainly during the period from June to early August.


Assuntos
Monitoramento Ambiental , Isótopos de Oxigênio/análise , Estações do Ano , Vapor , China , Cidades , Clima , Chuva , Temperatura
18.
Huan Jing Ke Xue ; 33(9): 2924-31, 2012 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-23243840

RESUMO

Based on the data of the hydrogen and oxygen stable isotopes in precipitation over Northeast China provided by the Global Network of Isotopes in Precipitation (GNIP) and the meteorological statistics, the spatial and temporal variations of stable isotopes in precipitation and their influencing factors were analyzed and the Local Meteoric Water Line (LMWL) was established. The results were as follows: delta18O value was low in winter and high in summer; the spatial distribution showed that the weighted delta18O value decreased from the south to the north; the linear relationship between delta18O in precipitation and temperature was significant, but no linear relationship was found for the precipitation amount; delta18O in precipitation can be evaluated quantitatively based on a multiple linear regression equation with delta18O and related parameters (temperature, precipitation amount, elevation, longitude and latitude). The water vapor source of the sampling sites was tracked by HYSPLIT 4. 9 model, and the modeled trajectory of vapor source indicated that there were two main paths, including the cold wet water vapor from the Atlantic Ocean and the Arctic Ocean via Westerlies, and the warm one from the Pacific Ocean.


Assuntos
Monitoramento Ambiental/métodos , Isótopos de Oxigênio/análise , Chuva/química , Movimentos da Água , China , Poluentes Ambientais/análise , Poluentes Ambientais/química , Vapor/análise
19.
Huan Jing Ke Xue ; 33(6): 1936-43, 2012 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22946179

RESUMO

Based on the daily air pollution index (API), primary pollutant, air quality level and status of 42 cities in China during 2001-2010, the characteristics of air quality were analyzed. The results showed that the atmosphere was significantly influenced by consumption of coal. The primary pollutant was PM10, and the air quality status was excellent (0 < API < 50), good (50 < API <100) and slightly polluted (100 < API < 150) in the majority. The air pollution status varied seasonally, which was the most serious in winter, and slightest in summer. The air quality was better and better in the observed period generally; The spatial distribution of urban air environment displayed a worsening trend from the south to the north and from the coasts to the inland; The local emission and natural dust transmission from the Northwest China was the main sources of urban air pollution; The air pollutants were impacted by the meteorological elements, and the air pollution index correlated linearly with precipitation, wind speed and temperature inversion; The distribution of weather conditions, which was affected by the terrain, also could influence the air quality; In addition, the human activities had both positive and negative functions on the urban air quality.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental/métodos , Poluição do Ar/análise , China , Cidades , Carvão Mineral , Poeira/análise , Material Particulado/análise , Estações do Ano
20.
Huan Jing Ke Xue ; 33(3): 679-86, 2012 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-22624355

RESUMO

The snow and ice samples, collected at Glacier No. 1 at the headwaters of Urumqi River (UG1) and Glacier No. 51 at Haxilegen of Kuytun River (HG51) in 2002 and 2004, were analyzed for organic carbon (OC) and element carbon (EC) by thermal/ optical reflectance (TOR). The spatio-temporal characteristics and environmental significance of OC and EC concentration were discussed in details. The concentration order of total carbon (TC) was: snowpack of west branch on UG1 (1 943 ng x g(-1)) > snowpack of east branch on UG1 (989 ng x g(-1)) > snowpack of HG51 (150 ng x g(-1)) > glacier ice of east branch on UG1 (77 ng x g(-1)), and the concentration order of OC and EC lay similar as TC. The concentration of OC and EC in snowpack of Tianshan Mountains were 557 ng x g(-1) and 188 ng x g(-1), respectively. Concentration peak of carbonaceous aerosol usually appeared near the dust layer at the bottom section of snowpack, but the some sudden events could increase the concentration in the surface snow. Because of the seasonality of carbon emission (e. g. heating and agricultural activities) and transportation (e. g. atmospheric circulation), the concentration of carbonaceous aerosol increased from July to November with fluctuations. Difference on the order of magnitude might exist between the concentration in snow (firn) and glacier ice, which was influenced by the glacier surroundings, sampling situation and other factors. EC on the surface snow affected the albedo significantly, and an average albedo reduction of 0.22 in the wavelength of 300-700 nm was simulated by SNICAR (snow, ice, and aerosol radiative) model.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Carbono/análise , Monitoramento Ambiental , Camada de Gelo/química , China , Neve/química
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