[Objective] The aim was to obtain the full-length cDNA sequence of Dunaliella parva β-actin gene.[Method] Based on the highly conserved amino acid regions of known β-actin,a pair of degenerate primers was synthesize...[Objective] The aim was to obtain the full-length cDNA sequence of Dunaliella parva β-actin gene.[Method] Based on the highly conserved amino acid regions of known β-actin,a pair of degenerate primers was synthesized to amplify 533 bp cDNA sequences in Dunaliella parva.Then,the 5＇ genomic DNA and 3＇ cDNA sequences were obtained by Genome walking and 3＇-RACE technology based on the obtained sequence.According to the sequences of the 5＇-termini and 3＇-termini,specific primers were synthesized to obtain the full-length cDNA.[Result] The full-length β-actin cDNA included 1 137 bp open reading frame（ORF）,617 bp of 3＇ noncoding region.Similarity analysis indicated that the highest similarity was found between Dunaliella parva and Dunaliella salina.The Dunaliella parva β-actin also showed wide similarity with other algae.[Conclusion] The full-length cDNA sequence of D.parva was firstly obtained,which was highly conserved.展开更多
The Red-breasted Flycatcher （Ficedula parva） and Taiga Flycatcher （F albicila） have long been considered having a conspecific status under the species Red-throated Flycatcher （Fparva）. Based on the studies on th...The Red-breasted Flycatcher （Ficedula parva） and Taiga Flycatcher （F albicila） have long been considered having a conspecific status under the species Red-throated Flycatcher （Fparva）. Based on the studies on the morphology, vocalizations and molecular biology, the two subspecies have recently been split into separate species that are allopatrically distributed in the Palearctic region. Before our report, there was no formal record of taxon parva in China. Between April and May of 2007, two birds of parva were recorded respectively at Potoi Island, Hong Kong SAR and Xiangyundao Tree Farm, Laoting, Hebei Province, the first known recording of this species in China. We also briefly discussed the general characteristics and field identification of Red-breasted Flycatchers in this article.展开更多
Reproductive traits of one invasive population in Lake Fuxian and two native populations in Lakes Chao and Dongting for Pseudorasbora parva were investigated to determine the variations in their reproductive strategie...Reproductive traits of one invasive population in Lake Fuxian and two native populations in Lakes Chao and Dongting for Pseudorasbora parva were investigated to determine the variations in their reproductive strategies associated with the change of environmental conditions. Compared with the two native populations, P.parva markedly experienced the protraction in their spawning time and the decrease in mortality for adult individuals in Lake Fuxian. The three populations all got their first sexual maturity at the same age, but their total lengths at maturity were quite different for those in Lake Chao were significantly lower than in Lakes Fuxian and Dongting. Additionally, in spite that no significant difference occurred in their relative fecundities for P. parva in Lakes Fuxian and Dongting, the population in Lake Chao showed the markedly higher relative fecundity than the other two populations. These results were analyzed with the variations in water temperature, nutrient status, fishing stress among the three lakes. The relative decline in fecundity for the invasive population, which conflicted with the enemy release hypothesis, was disscussed with the context of the preponderance of another invasive fish, Neosalanx taihuensis, in Lake Fuxian.展开更多
In recent years, fish invasion has become one of the main reasons for the decline of native fish stocks. Pseudorasbora parva is considered one of the major invasive species worldwide. The present study investigated th...In recent years, fish invasion has become one of the main reasons for the decline of native fish stocks. Pseudorasbora parva is considered one of the major invasive species worldwide. The present study investigated the fish resources of the Chabalang Wetland (Lhasa, Tibet) during diff erent seasons in 2009 and 2013. Four hundred and twelve individuals were subsampled to estimate age, growth, and feeding habit of P . parva . Furthermore, food relationships between P . parva and the native Schizothoracinae fish were also examined. The results revealed a significant shift in species composition and community structure characterized by the disappearance of native fish and outbreak of non-native fish. The percentage of nonnative P . parva in the fish collections significantly increased from 33.64% in 2009 to 64.08% in 2013. The standard length (SL) ranged from 22.00 to 78.71 mm, and their age was 1–5 a. The von Bertalanff y function was used to model the observed length-at-age data as L t =112.19(1–e^-0.1495 ( t +0.8012)) for females and as L t =123.12 (1–e^-0.1500 ( t +0.7132)) for males. The results indicated that P . parva in Tibet has lower growth and mortality rates compared with that from the native ranges. Ninety-seven prey taxa belonging to 9 prey categories were identified in the gut of 38 P . parva . P . parva can be considered a generalized and opportunistic predator, competing with the native fish, especially Schizothorax o’connori , Schizopygopsis younghusbandi younghusbandi , and Ptychobarbus dipogon , for Bacillariophyta and Chironomid larvae. This is an important reason for the decline in native fish population.展开更多
Theileria parva is a protozoan parasite that causes the disease East Coast fever in cattle which results in major economic losses in Eastern, Central and Southern Africa. Efforts to generate vaccines involve measureme...Theileria parva is a protozoan parasite that causes the disease East Coast fever in cattle which results in major economic losses in Eastern, Central and Southern Africa. Efforts to generate vaccines involve measurements of cytotoxic activity since CD8 cells are believed to be responsible for protection of the animals. CTL assays are time consuming, and may require use of radioactive material and they also impose a considerable amount of in vitro work, which may skew the response compared to ex vivo assays. Hence it would be beneficial to identify other markers that correlate with the cytotoxicity. In this in vitro study we examined if the number of tetramer positive CD8 cells and the staining intensity of these correlated with lysis of the target cells. Furthermore, we investigated if the expression of the activation marker perforin correlated with the cytotoxicity. Perforin is involved in permeabilization of the cell membrane of the target cell. Bulk CTL lines and purified CD8 cell lines generated from cattle of the A18 BoLA (MHC) type were analysed for the Theileria parva specific immune responses using a peptide-MHC tetramer and antibodies for perforinin FACS analysis. Thelysis of target cells was determined by a chromium release assay. Results demonstrate that the percentage of tetramer positive cells, in six cell lines generated against the whole parasite, correlate with killing of PBMC pulsed with the peptide. The product of the percentages of perforin and tetramer double positive cells and the net MFI of perforin showed a perfect correlation with the cytotoxicity of the peptide pulsed PBMC. Likewise, the product of percentage perforin positive cells and the staining intensity had the best significant correlation with killing of the pulsed PBMC. The present results suggest that perforin could be a possible biomarker for the cytotoxicity to Theileria parva infections/immunizations.展开更多
基金Supported by Comprehensive Strategic Cooperation Project betweenGuangdong Province and Chinese Academy of Sciences (2010A0-90100010)National Key Technology R&D Program of the 12thFive-year Plan of China (2011BAD14B03)Foundation of KeyLaboratory of Renewable Energy and Natural Gas Hydrate,ChineseAcademy of Sciences (y107j6)~~
文摘[Objective] The aim was to obtain the full-length cDNA sequence of Dunaliella parva β-actin gene.[Method] Based on the highly conserved amino acid regions of known β-actin,a pair of degenerate primers was synthesized to amplify 533 bp cDNA sequences in Dunaliella parva.Then,the 5＇ genomic DNA and 3＇ cDNA sequences were obtained by Genome walking and 3＇-RACE technology based on the obtained sequence.According to the sequences of the 5＇-termini and 3＇-termini,specific primers were synthesized to obtain the full-length cDNA.[Result] The full-length β-actin cDNA included 1 137 bp open reading frame（ORF）,617 bp of 3＇ noncoding region.Similarity analysis indicated that the highest similarity was found between Dunaliella parva and Dunaliella salina.The Dunaliella parva β-actin also showed wide similarity with other algae.[Conclusion] The full-length cDNA sequence of D.parva was firstly obtained,which was highly conserved.
文摘The Red-breasted Flycatcher （Ficedula parva） and Taiga Flycatcher （F albicila） have long been considered having a conspecific status under the species Red-throated Flycatcher （Fparva）. Based on the studies on the morphology, vocalizations and molecular biology, the two subspecies have recently been split into separate species that are allopatrically distributed in the Palearctic region. Before our report, there was no formal record of taxon parva in China. Between April and May of 2007, two birds of parva were recorded respectively at Potoi Island, Hong Kong SAR and Xiangyundao Tree Farm, Laoting, Hebei Province, the first known recording of this species in China. We also briefly discussed the general characteristics and field identification of Red-breasted Flycatchers in this article.
基金funded by the Key Project for Knowledge Innovation of CAS(No.KSCX1-SW-13-04)the National Key Project for Basic Research of China (No.2009CB119200)
文摘Reproductive traits of one invasive population in Lake Fuxian and two native populations in Lakes Chao and Dongting for Pseudorasbora parva were investigated to determine the variations in their reproductive strategies associated with the change of environmental conditions. Compared with the two native populations, P.parva markedly experienced the protraction in their spawning time and the decrease in mortality for adult individuals in Lake Fuxian. The three populations all got their first sexual maturity at the same age, but their total lengths at maturity were quite different for those in Lake Chao were significantly lower than in Lakes Fuxian and Dongting. Additionally, in spite that no significant difference occurred in their relative fecundities for P. parva in Lakes Fuxian and Dongting, the population in Lake Chao showed the markedly higher relative fecundity than the other two populations. These results were analyzed with the variations in water temperature, nutrient status, fishing stress among the three lakes. The relative decline in fecundity for the invasive population, which conflicted with the enemy release hypothesis, was disscussed with the context of the preponderance of another invasive fish, Neosalanx taihuensis, in Lake Fuxian.
基金Supported by the National Key Technology R&D Program(No.2015BAD13B06)the Finance Special Fund of Chinese Ministry of Agriculture(Fisheries Resources and Environment Survey in the Key Water Areas of Tibet)
文摘In recent years, fish invasion has become one of the main reasons for the decline of native fish stocks. Pseudorasbora parva is considered one of the major invasive species worldwide. The present study investigated the fish resources of the Chabalang Wetland (Lhasa, Tibet) during diff erent seasons in 2009 and 2013. Four hundred and twelve individuals were subsampled to estimate age, growth, and feeding habit of P . parva . Furthermore, food relationships between P . parva and the native Schizothoracinae fish were also examined. The results revealed a significant shift in species composition and community structure characterized by the disappearance of native fish and outbreak of non-native fish. The percentage of nonnative P . parva in the fish collections significantly increased from 33.64% in 2009 to 64.08% in 2013. The standard length (SL) ranged from 22.00 to 78.71 mm, and their age was 1–5 a. The von Bertalanff y function was used to model the observed length-at-age data as L t =112.19(1–e^-0.1495 ( t +0.8012)) for females and as L t =123.12 (1–e^-0.1500 ( t +0.7132)) for males. The results indicated that P . parva in Tibet has lower growth and mortality rates compared with that from the native ranges. Ninety-seven prey taxa belonging to 9 prey categories were identified in the gut of 38 P . parva . P . parva can be considered a generalized and opportunistic predator, competing with the native fish, especially Schizothorax o’connori , Schizopygopsis younghusbandi younghusbandi , and Ptychobarbus dipogon , for Bacillariophyta and Chironomid larvae. This is an important reason for the decline in native fish population.
文摘Theileria parva is a protozoan parasite that causes the disease East Coast fever in cattle which results in major economic losses in Eastern, Central and Southern Africa. Efforts to generate vaccines involve measurements of cytotoxic activity since CD8 cells are believed to be responsible for protection of the animals. CTL assays are time consuming, and may require use of radioactive material and they also impose a considerable amount of in vitro work, which may skew the response compared to ex vivo assays. Hence it would be beneficial to identify other markers that correlate with the cytotoxicity. In this in vitro study we examined if the number of tetramer positive CD8 cells and the staining intensity of these correlated with lysis of the target cells. Furthermore, we investigated if the expression of the activation marker perforin correlated with the cytotoxicity. Perforin is involved in permeabilization of the cell membrane of the target cell. Bulk CTL lines and purified CD8 cell lines generated from cattle of the A18 BoLA (MHC) type were analysed for the Theileria parva specific immune responses using a peptide-MHC tetramer and antibodies for perforinin FACS analysis. Thelysis of target cells was determined by a chromium release assay. Results demonstrate that the percentage of tetramer positive cells, in six cell lines generated against the whole parasite, correlate with killing of PBMC pulsed with the peptide. The product of the percentages of perforin and tetramer double positive cells and the net MFI of perforin showed a perfect correlation with the cytotoxicity of the peptide pulsed PBMC. Likewise, the product of percentage perforin positive cells and the staining intensity had the best significant correlation with killing of the pulsed PBMC. The present results suggest that perforin could be a possible biomarker for the cytotoxicity to Theileria parva infections/immunizations.
