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1.
Angew Chem Int Ed Engl ; 59(49): 22109-22116, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32748542

RESUMO

The capability to significantly shorten the synthetic period of a broad spectrum of open organic materials presents an enticing prospect for materials processing and applications. Herein we discovered 1,2,4-triazolium poly(ionic liquid)s (PILs) could serve as a universal additive to accelerate by at least one order of magnitude the growth rate of representative imine-linked crystalline open organics, including organic cages, covalent organic frameworks (COFs), and macrocycles. This phenomenon results from the active C5-protons in poly(1,2,4-triazolium)s that catalyze the formation of imine bonds, and the simultaneous salting-out effect (induced precipitation by decreasing solubility) that PILs exert on these crystallizing species.

2.
Yi Chuan ; 41(12): 1138-1147, 2019 Dec 20.
Artigo em Chinês | MEDLINE | ID: mdl-31857285

RESUMO

Pathogenic Escherichia coli (E. coli) is the most common pathogen causing urinary tract infection in animals. We investigated the antibiotic resistance and virulence genes of pathogenic E. coli CCHTP derived from urine with occult blood of the giant panda by whole genome sequencing. The flanking sequencing of resistance and virulence genes in genomic islands were also analyzed. Our results demonstrate that E. coli CCHTP contains different families of antibiotic resistance genes, most of which are efflux pump related genes, including multiple drug resistance efflux pump genes mdfA, emrE, and mdtN. A total of 166 virulence factors and 563 virulence genes were identified, and the most virulence factors and related genes are involved in host cell attachment and invasion processes. Furthermore, sequence analysis of 19 genomic islands revealed that antibiotic and virulence genes are associated with mobile genetic elements (transposon and insertion sequence) in GIs011 and GIs017. These structures can mediate horizontal transfer of antibiotic and virulence genes. Our work described the distribution of antibiotic resistance genes and virulence genes in E. coli CCHTP, which may provide an important guidance for treatment and rational drug use of E. coli CCHTP infection in the giant panda.


Assuntos
Farmacorresistência Bacteriana , Proteínas de Escherichia coli , Escherichia coli , Urina , Ursidae , Animais , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Genoma Bacteriano , Urina/microbiologia , Ursidae/microbiologia , Virulência/genética , Fatores de Virulência/genética , Sequenciamento Completo do Genoma
3.
Biomolecules ; 9(9)2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31480517

RESUMO

Post-thawed sperm quality parameters vary across different species after cryopreservation. To date, the molecular mechanism of sperm cryoinjury, freeze-tolerance and other influential factors are largely unknown. In this study, significantly dysregulated microRNAs (miRNAs) and mRNAs in boar and giant panda sperm with different cryo-resistance capacity were evaluated. From the result of miRNA profile of fresh and frozen-thawed giant panda sperm, a total of 899 mature, novel miRNAs were identified, and 284 miRNAs were found to be significantly dysregulated (195 up-regulated and 89 down-regulated). Combined analysis of miRNA profiling of giant panda sperm and our previously published data on boar sperm, 46, 21 and 4 differentially expressed (DE) mRNAs in boar sperm were believed to be related to apoptosis, glycolysis and oxidative phosphorylation, respectively. Meanwhile, 87, 17 and 7 DE mRNAs in giant panda were associated with apoptosis, glycolysis and oxidative phosphorylation, respectively. Gene ontology (GO) analysis of the targets of DE miRNAs showed that they were mainly distributed on membrane related pathway in giant panda sperm, while cell components and cell processes were tied to the targets of DE miRNAs in boar sperm. Finally, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of DE mRNAs indicated that most of these DE mRNAs were distributed in membrane signal transduction-related pathways in giant panda sperm, while those in boar sperm were mainly distributed in the cytokine-cytokine receptor interaction pathway and inflammatory related pathways. In conclusion, although the different freezing extenders and programs were used, the DE miRNAs and mRNAs involved in apoptosis, energy metabolism, olfactory transduction pathway, inflammatory response and cytokine-cytokine interactions, could be the possible molecular mechanism of sperm cryoinjury and freeze tolerance.


Assuntos
Congelamento , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Espermatozoides/metabolismo , Espermatozoides/fisiologia , Animais , Criopreservação , Masculino , Sus scrofa , Ursidae
4.
Cells ; 8(3)2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30893784

RESUMO

Few major histocompatibility complex (MHC)-based mate choice studies include all MHC genes at the inter-individual, sperm-egg, and mother-fetus recognition levels. We tested three hypotheses of female mate choice in a 17-year study of the giant panda (Ailuropoda melanoleuca) while using ten functional MHC loci (four MHC class I loci: Aime-C, Aime-F, Aime-I, and Aime-L; six MHC class II loci: Aime-DRA, Aime-DRB3, Aime-DQA1, Aime-DQA2, Aime-DQB1, and Aime-DQB2); five super haplotypes (SuHa, SuHaI, SuHaII, DQ, and DR); and, seven microsatellites. We found female choice for heterozygosity at Aime-C, Aime-I, and DQ and for disassortative mate choice at Aime-C, DQ, and DR at the inter-individual recognition level. High mating success occurred in MHC-dissimilar mating pairs. No significant results were found based on any microsatellite parameters, suggesting that MHCs were the mate choice target and there were no signs of inbreeding avoidance. Our results indicate Aime-DQA1- and Aime-DQA2-associated disassortative selection at the sperm-egg recognition level and a possible Aime-C- and Aime-I-associated assortative maternal immune tolerance mechanism. The MHC genes were of differential importance at the different recognition levels, so all of the functional MHC genes should be included when studying MHC-dependent reproductive mechanisms.


Assuntos
Feto/fisiologia , Complexo Principal de Histocompatibilidade/genética , Óvulo/fisiologia , Reprodução/genética , Espermatozoides/fisiologia , Ursidae/genética , Ursidae/fisiologia , Alelos , Animais , Feminino , Variação Genética , Haplótipos/genética , Heterozigoto , Homozigoto , Masculino , Repetições de Microssatélites/genética
5.
Int J Mol Sci ; 19(10)2018 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297640

RESUMO

Sperm cryopreservation and artificial insemination are important methods for giant panda breeding and preservation of extant genetic diversity. Lower conception rates limit the use of artificial insemination with frozen-thawed giant panda sperm, due to the lack of understanding of the cryodamaging or cryoinjuring mechanisms in cryopreservation. Long non-coding RNAs (lncRNAs) are involved in regulating spermatogenesis. However, their roles during cryopreservation remain largely unexplored. Therefore, this study aimed to identify differentially expressed lncRNAs and mRNAs associated with cryodamage or freeze tolerance in frozen-thawed sperm through high throughput sequencing. A total of 61.05 Gb clean reads and 22,774 lncRNA transcripts were obtained. From the sequencing results, 1477 significantly up-regulated and 1,396 significantly down-regulated lncRNA transcripts from fresh and frozen-thawed sperm of giant panda were identified. GO and KEGG showed that the significantly dysregulated lncRNAs and mRNAs were mainly involved in regulating responses to cold stress and apoptosis, such as the integral component of membrane, calcium transport, and various signaling pathways including PI3K-Akt, p53 and cAMP. Our work is the first systematic profiling of lncRNA and mRNA in fresh and frozen-thawed giant panda sperm, and provides valuableinsights into the potential mechanism of cryodamage in sperm.


Assuntos
Criopreservação , Preservação do Sêmen/efeitos adversos , Espermatozoides/metabolismo , Transcriptoma , Ursidae/genética , Animais , Espécies em Perigo de Extinção , Masculino , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Preservação do Sêmen/métodos
6.
Sci Rep ; 8(1): 12308, 2018 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-30120296

RESUMO

ß-Defensins are small antimicrobial proteins expressed in various organisms and have great potential for improving animal health and selective breeding programs. Giant pandas have a distinctive lineage in Carnivora, and it is unclear whether ß-defensin genes have experienced different selective pressures during giant panda evolution. We therefore characterized the giant panda (Ailuropoda melanoleuca) ß-defensin gene family through gap filling, TBLASTN, and HMM searches. Among 36 ß-defensins identified, gastrointestinal disease may induce the expression of the DEFB1 and DEFB139 genes in the digestive system. Moreover, for DEFB139, a significant positive selection different from that of its homologs was revealed through branch model comparisons. A Pro-to-Arg mutation in the giant panda DEFB139 mature peptide may have enhanced the peptide's antimicrobial potency by increasing its stability, isoelectric point, surface charge and surface hydrophobicity, and by stabilizing its second ß-sheet. Broth microdilution tests showed that the increase in net charge caused by the Pro-to-Arg mutation has enhanced the peptide's potency against Staphylococcus aureus, although the increase was minor. We expect that additional gene function and expression studies of the giant panda DEFB139 gene could improve the existing conservation strategies for the giant panda.


Assuntos
Anti-Infecciosos/química , Ursidae/genética , beta-Defensinas/química , beta-Defensinas/genética , Sequência de Aminoácidos , Animais , Ponto Isoelétrico , Mutação , Filogenia
7.
Asian Pac J Trop Med ; 10(8): 813-818, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28942831

RESUMO

OBJECTIVE: To further explore the function of combine use of tetramethylpyrazine (TMP) and cisplatin (DDP) in lung carcinoma. METHODS: We used the combination drug to treat Lewis lung cancer mice, investigated the expression level of vascular endothelial growth factor (VEGF), Kruppel-like factor 4 (KLF4) and A disintegrin and metalloproteinase with thrombospondin motifs 1 (ADAMTS1) and to further explore the inhibitory effects and potential mechanism of TMP combined with DDP on tumor angiogenesis. RESULTS: The tumor growth was suppressed in TMP group, DDP group and TMP combined with DDP group. Furthermore, the weights and volume of tumor, the expression level of VEGF, KLF4 and ADAMTS1 were found significantly changed between experiment group and control group. These findings suggest that TMP with DDP had additional or synergistic effects to inhibit the tumor growth effectively, might be achieved through reducing the expression of angiogenesis promoting factor VEGF and increasing expression of angiogenesis inhibitors KLF4 and ADAMTS1. CONCLUSION: KLF4 and ADAMTS1 may be synergically involved in the angiogenesis in mouse Lewis lung cancer through the different signal ways.

8.
PeerJ ; 5: e3358, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28560107

RESUMO

Fecal samples play an important role in giant panda conservation studies. Optimal preservation conditions and choice of microsatellites for giant panda fecal samples have not been established. In this study, we evaluated the effect of four factors (namely, storage type (ethanol (EtOH), EtOH -20 °C, 2-step storage medium, DMSO/EDTA/Tris/salt buffer (DETs) and frozen at -20 °C), storage time (one, three and six months), fragment length, and repeat motif of microsatellite loci) on the success rate of microsatellite amplification, allelic dropout (ADO) and false allele (FA) rates from giant panda fecal samples. Amplification success and ADO rates differed between the storage types. Freezing was inferior to the other four storage methods based on the lowest average amplification success and the highest ADO rates (P < 0.05). The highest microsatellite amplification success was obtained from either EtOH or the 2-step storage medium at three storage time points. Storage time had a negative effect on the average amplification of microsatellites and samples stored in EtOH and the 2-step storage medium were more stable than the other three storage types. We only detected the effect of repeat motif on ADO and FA rates. The lower ADO and FA rates were obtained from tri- and tetra-nucleotide loci. We suggest that freezing should not be used for giant panda fecal preservation in microsatellite studies, and EtOH and the 2-step storage medium should be chosen on priority for long-term storage. We recommend candidate microsatellite loci with longer repeat motif to ensure greater genotyping success for giant panda fecal studies.

9.
Gene ; 592(2): 303-7, 2016 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-27421668

RESUMO

As the rate-limiting enzyme of the mitochondrial respiratory chain, cytochrome c oxidase (COX) plays a crucial role in biological metabolism. "Living fossil" giant panda (Ailuropoda melanoleuca) is well-known for its special bamboo diet. In an effort to explore functional variation of COX1 in the energy metabolism behind giant panda's low-energy bamboo diet, we looked at genetic variation of COX1 gene in giant panda, and tested for its selection effect. In 1545 base pairs of the gene from 15 samples, 9 positions were variable and 1 mutation leaded to an amino acid sequence change. COX1 gene produces six haplotypes, nucleotide (pi), haplotype diversity (Hd). In addition, the average number of nucleotide differences (k) is 0.001629±0.001036, 0.8083±0.0694 and 2.517, respectively. Also, dN/dS ratio is significantly below 1. These results indicated that giant panda had a low population genetic diversity, and an obvious purifying selection of the COX1 gene which reduces synthesis of ATP determines giant panda's low-energy bamboo diet. Phylogenetic trees based on the COX1 gene were constructed to demonstrate that giant panda is the sister group of other Ursidae.


Assuntos
Ciclo-Oxigenase 1/genética , Evolução Molecular , Ursidae/genética , Animais , Ciclo-Oxigenase 1/classificação , Haplótipos , Filogenia , Subunidades Proteicas/genética , Seleção Genética
10.
Biopreserv Biobank ; 13(3): 195-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26035009

RESUMO

The giant panda Ailuropoda melanoleuca is an endangered species and is a symbol for wildlife conservation. Although efforts have been made to protect this rare and endangered species through breeding and conservative biology, the long-term preservation of giant panda genome resources (gametes, tissues, organs, genomic libraries, etc.) is still a practical option. In this study, the giant panda skeletal muscle-derived cell line was successfully established via primary explants culture and cryopreservation techniques. The population doubling time of giant panda skeletal cells was approximately 33.8 h, and this population maintained a high cell viability before and after cryopreservation (95.6% and 90.7%, respectively). The two skeletal muscle-specific genes SMYD1 and MYF6 were expressed and detected by RT-PCR in the giant panda skeletal muscle-derived cell line. Karyotyping analysis revealed that the frequencies of giant panda skeletal muscle cells showing a chromosome number of 2n=42 ranged from 90.6∼94.2%. Thus, the giant panda skeletal muscle-derived cell line provides a vital resource and material platform for further studies and is likely to be useful for the protection of this rare and endangered species.


Assuntos
Criopreservação/métodos , Músculo Esquelético/citologia , Ursidae , Animais , Linhagem Celular , Proliferação de Células , Cromossomos de Mamíferos/metabolismo , Regulação da Expressão Gênica , Cariotipagem , Masculino , Metáfase , Células Musculares/citologia , Especificidade de Órgãos/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
11.
BMC Genomics ; 16: 61, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25888121

RESUMO

BACKGROUND: The giant panda (Ailuropoda melanoleuca) is a critically endangered species endemic to China. Microsatellites have been preferred as the most popular molecular markers and proven effective in estimating population size, paternity test, genetic diversity for the critically endangered species. The availability of the giant panda complete genome sequences provided the opportunity to carry out genome-wide scans for all types of microsatellites markers, which now opens the way for the analysis and development of microsatellites in giant panda. RESULTS: By screening the whole genome sequence of giant panda in silico mining, we identified microsatellites in the genome of giant panda and analyzed their frequency and distribution in different genomic regions. Based on our search criteria, a repertoire of 855,058 SSRs was detected, with mono-nucleotides being the most abundant. SSRs were found in all genomic regions and were more abundant in non-coding regions than coding regions. A total of 160 primer pairs were designed to screen for polymorphic microsatellites using the selected tetranucleotide microsatellite sequences. The 51 novel polymorphic tetranucleotide microsatellite loci were discovered based on genotyping blood DNA from 22 captive giant pandas in this study. Finally, a total of 15 markers, which showed good polymorphism, stability, and repetition in faecal samples, were used to establish the novel microsatellite marker system for giant panda. Meanwhile, a genotyping database for Chengdu captive giant pandas (n = 57) were set up using this standardized system. What's more, a universal individual identification method was established and the genetic diversity were analysed in this study as the applications of this marker system. CONCLUSION: The microsatellite abundance and diversity were characterized in giant panda genomes. A total of 154,677 tetranucleotide microsatellites were identified and 15 of them were discovered as the polymorphic and stable loci. The individual identification method and the genetic diversity analysis method in this study provided adequate material for the future study of giant panda.


Assuntos
Variação Genética , Repetições de Microssatélites/genética , Ursidae/genética , Animais , Sequência de Bases , Mapeamento Cromossômico , Genoma , Genótipo , Dados de Sequência Molecular
12.
Ying Yong Sheng Tai Xue Bao ; 21(7): 1709-17, 2010 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-20879527

RESUMO

From 2003 to 2007, the methods of plot sampling and positioning observation were adopted to investigate the population density, basal diameter, and plant height of Umbrella bamboo (Fargesia robusta) clone in the Wolong Natural Reserve of China. In the meantime, the effects of wilderness-training Ailuropoda melanoleuca's feeding and artificial harvesting on the population regeneration of the clone were studied, and the responses of the population structure (age-, size-, and height-class distribution) to different management modes (A. melanoleuca's feeding, artificial harvesting, control) were approached with the scale- and shape-parameters of Weibull distribution function. The results showed that under the same F. robusta clone population density and the same environmental conditions (P>0.05), A. melanoleuca's feeding and artificial harvesting promoted the clone regeneration. After 3 years natural restoration, the population density of the clone tended to be equal to the control, and came to a steady state (P>0.05). The curves of size- and height-class distribution as well as the scale- and shape-parameters had no significant differences between A. melanoleuca's feeding plot and control plot. The curves of size- and height-class distribution in artificial harvesting plot were in converse "J" shape, and the values of the scale- and shape-parameters were significantly lower than those in the other two plots (P<0.05). The young and adult bamboos in artificial harvesting plot were far poor in shoot quality, and A. melanoleuca rejected to feed with them.


Assuntos
Bambusa/crescimento & desenvolvimento , Ecossistema , Comportamento Alimentar/fisiologia , Reprodução Assexuada , Ursidae/fisiologia , Animais , China , Densidade Demográfica
13.
J Exp Zool B Mol Dev Evol ; 314(3): 208-23, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19950128

RESUMO

Ample variations of the major histocompatibility complex (MHC) genes are essential for vertebrates to adapt to various environmental conditions. In this study, we investigated the genetic variations and evolutionary patterns of seven functional MHC class II genes (one DRA, two DRB, two DQA, and two DQB) of the giant panda. The results showed the presence of two monomorphic loci (DRA and DQB2) and five polymorphic loci with different numbers of alleles (seven at DRB1, six at DRB3, seven at DQA1, four at DQA2, six at DQB1). The presence of balancing selection in the giant panda was supported by the following pieces of evidence: (1) The observed heterozygosity was higher than expected. (2) Amino acid heterozygosity was significantly higher at antigen-binding sites (ABS) compared with non-ABS sequences. (3) The selection parameter omega (d(N)/d(S)) was significantly higher at ABS compared with non-ABS sequences. (4) Approximately 95.45% of the positively selected codons (P>0.95) were located at or adjacent to an ABS. Furthermore, this study showed that (1) The Qinling subspecies exhibited high omega values across each locus (all >1), supporting its extensive positive selection. (2) The Sichuan subspecies displayed small omega at DRB1 (omega<0.72) and DQA2 (omega<0.48), suggesting that these sites underwent strong purifying selection. (3) Intragenic recombination was detected in DRB1, DQA1, and DQB1. The molecular diversity in classic Aime-MHC class II genes implies that the giant panda had evolved relatively abundant variations in its adaptive immunity along the history of host-pathogen co-evolution. Collectively, these findings indicate that natural selection accompanied by recombination drives the contrasting diversity patterns of the MHC class II genes between the two studied subspecies of giant panda.


Assuntos
Genes MHC da Classe II/genética , Variação Genética , Recombinação Genética , Seleção Genética , Ursidae/genética , Ursidae/imunologia , Sequência de Aminoácidos , Animais , Frequência do Gene , Heterozigoto , Dados de Sequência Molecular , Alinhamento de Sequência , Especificidade da Espécie
14.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 24(5): 579-81, 2007 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-17922433

RESUMO

OBJECTIVE: To detect the correlation between the microsatellite DNA polymorphism of adrenomedullin(ADM) gene (repeated sequences of CA) and the atherosclerotic cerebral infarction (ACI). METHODS: With PCR, ADM genotype was monitored from 189 normotensive subjects and 283 cerebral infarction patients. By using radioimmunoassay, their plasma ADM concentration was measured, so as the biochemical index. RESULTS: The genotype distribution of ADM between the health control and ACI groups was significantly different, chi square was 28.732, P < 0.05. As one of the four alleles, including 11, 13, 14 and 19 alleles, the frequency of 19 allele in ACI groups was much higher than that in the health control group, chi square was 26.929, P < 0.05. However, there was no significant difference in plasma ADM concentration among the different genotypes of the ACI patients. CONCLUSION: Microsatellite DNA polymorphism of ADM gene may be associated with the genetic predisposition to ACI.


Assuntos
Adrenomedulina/genética , Infarto Cerebral/genética , Arteriosclerose Intracraniana/genética , Repetições de Microssatélites/genética , Polimorfismo Genético , Adulto , Idoso , Alelos , Estudos de Casos e Controles , Infarto Cerebral/complicações , Feminino , Frequência do Gene , Genótipo , Humanos , Arteriosclerose Intracraniana/complicações , Masculino , Pessoa de Meia-Idade
15.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 19(6): 353-7, 2007 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-17577444

RESUMO

OBJECTIVE: To explore the influence of adrenomedullin (ADM) on apoptosis of neuron, volume of infarction and the expression of early growth response gene-1 (Egr-1) mRNA in the rat with focal ischemia/reperfusion (I/R) injury. METHODS: Fifty-four SD rats were randomly divided into sham operation group, ADM femoral vein group, internal carotid artery group and lateral cerebral ventricle group. The model was reproduced by ligating the middle cerebral artery (MCA) with a ligature for 2 hours followed by injection of ADM through femoral artery, internal carotid artery and lateral cerebral ventricle before reperfusion for 22 hours. The volume of infarction was estimated with tetrazolium chloride (TTC) staining, apoptosis of the neuron was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) method, the positive expression of Egr-1 mRNA was detected by in-situ hybridization. RESULTS: The volume of infarction were smaller after the injection of ADM through different ways than that of I/R group. The result was better when the internal carotid artery and the lateral cerebral ventricle were used than that after injection by the way of the femoral vein (both P<0.05). There were few positive cells with TUNEL staining in the cerebral cortex and hippocampus CA1 zone in the sham operation group, and more apoptotic cells were seen in the group with focal brain I/R injury (both P<0.01). After the administration of ADM, especially through the internal carotid artery and the lateral cerebral ventricle, the number of the positive cells with TUNEL staining was decreased obviously compared with I/R group (both P<0.01). There was a little positive expression of Egr-1 mRNA in the cerebral cortex and hippocampus CA1 zone in sham operation group. The expression was enhanced in the group with focal brain I/R injury (both P<0.01). With the injection of ADM, the expression was much more enhanced, especially when internal carotid artery and the lateral cerebral ventricle were used for injection compared with those in I/R group (both P<0.01). CONCLUSION: The injection of ADM through different ways can reduce the neural injury, decrease the apoptosis of the neurons and the volume of the infarction, and increase the expression of Egr-1 mRNA. Therefore, it is efficacious in the treatment of cerebral ischemia.


Assuntos
Adrenomedulina/farmacologia , Apoptose/efeitos dos fármacos , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Neurônios/efeitos dos fármacos , Traumatismo por Reperfusão/patologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Masculino , Neurônios/metabolismo , Neurônios/patologia , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo
16.
Neurosci Bull ; 22(6): 323-30, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17690717

RESUMO

Objective To observe the influence of adrenomedullin (ADM) on neuron apoptosis, infarction volume of brain, and the expression of early growth response 1 (Egr-1) mRNA in ischemia-reperfusion rats. Methods The arteria cerebri media was tied for 2 h to construct the ischemia model. Infarction volume was detected by triphenltetrazolium chloride (TTC) staining, neuronal apoptosis and necrosis was detected with terminal deoxynucleotidyl transferase nick labeling (TUNEL) method, and the Egr-1 mRNA expression was examined by in situ hybridization (ISH). Results Infarction volume after ischemia-reperfusion is (269 +/- 20) mm(3). Infarction volume after injection of ADM through different ways are femoral vein (239 +/- 17) mm(3) (decreased by 11.2%), arteria carotis (214 +/- 14) mm(3) (by 20.4%) and lateral cerebral ventricle (209 +/- 13) mm(3) (by 22.3%), respectively. The results indicate that injecting ADM through arteria carotis and lateral cerebral ventricle is much more effective than it through femoral vein (P < 0.05). The TUNEL-positive cells in cerebral cortex or hippocampus are few in the sham operation group, but much more in the ischemia-reperfusion group. After being supplied with ADM, especially through arteria carotis interna or lateral cerebral ventricle way, the TUNEL-positive cells decreased obviously. Expression of Egr-1 mRNA was low in the cerebral cortex of the sham operation group rats, enhanced in the ischemia and reperfusion group rats, and enhanced markedly after treatment with ADM, especially through arteria carotis interna or lateral cerebral ventricle way (P < 0.01). Conclusion Injection of ADM through different ways could alleviate neural dysfunction, decrease neuron apoptosis and brain infarction volume, and increase the expression of Egr-1 mRNA.

17.
Cell Biol Int ; 27(4): 349-53, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12788051

RESUMO

In animal cloning, it is generally believed that the inactive diploid G(0)or G(1)stage of the cell cycle is beneficial to initiate cell-cycle coordination and reprogramming following transfer of the donor nucleus. Previous experiments have demonstrated that serum starvation results in quiescent cell stage. Some experiments show that the majority of cells in a fully confluent cell culture are also in an inactive G(1)stage. In order to provide more G(0)/G(1)stage cells for giant panda cloning, we carried out a flow cytometric analysis of the cell cycle of fibroblasts from the abdominal muscle of a giant panda at different passage numbers under different growth conditions, and after different periods of serum starvation. The percentage of G(0)+G(1)stage cells differed significantly under different growth conditions. Serum starvation effectively increased the percentage of G(0)+G(1)stage cells, and the cell cycle characteristics following serum starvation for varying periods of time differed with this and the initial confluency of the cultures. The data should help in choosing the optimal stage for preparing donor cells as well as increasing the potential cloning efficiency in our study of giant panda cloning.


Assuntos
Ciclo Celular , Fibroblastos/citologia , Citometria de Fluxo/métodos , Ursidae , Animais , Ciclo Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultura Livres de Soro/farmacologia , Feminino , Fibroblastos/efeitos dos fármacos
18.
Biol Reprod ; 67(2): 637-42, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12135908

RESUMO

Somatic cell nuclei of giant pandas can dedifferentiate in enucleated rabbit ooplasm, and the reconstructed eggs can develop to blastocysts. In order to observe whether these interspecies cloned embryos can implant in the uterus of an animal other than the panda, we transferred approximately 2300 panda-rabbit cloned embryos into 100 synchronized rabbit recipients, and none became pregnant. In another approach, we cotransferred both panda-rabbit and cat-rabbit interspecies cloned embryos into the oviducts of 21 cat recipients. Fourteen recipients exhibited estrus within 35 days; five recipients exhibited estrus 43-48 days after embryo transfer; and the other two recipients died of pneumonia, one of which was found to be pregnant with six early fetuses when an autopsy was performed. Microsatellite DNA analysis of these early fetuses confirmed that two were from giant panda-rabbit cloned embryos. The results demonstrated that panda-rabbit cloned embryos can implant in the uterus of a third species, the domestic cat. By using mitochondrial-specific probes of panda and rabbit, we found that mitochondria from both panda somatic cells and rabbit ooplasm coexisted in early blastocysts, but mitochondria from rabbit ooplasm decreased, and those from panda donor cells dominated in early fetuses after implantation. Our results reveal that mitochondria from donor cells may substitute those from recipient oocytes in postimplanted, interspecies cloned embryos.


Assuntos
Clonagem de Organismos/métodos , Implantação do Embrião/fisiologia , Mitocôndrias/metabolismo , Ursidae/fisiologia , Músculos Abdominais/citologia , Músculos Abdominais/ultraestrutura , Animais , Sequência de Bases , Gatos , Núcleo Celular/ultraestrutura , Células Cultivadas , DNA Mitocondrial/metabolismo , Transferência Embrionária , Desenvolvimento Embrionário e Fetal/fisiologia , Feminino , Repetições de Microssatélites , Dados de Sequência Molecular , Gravidez , Coelhos
19.
Shi Yan Sheng Wu Xue Bao ; 35(1): 62-5, 2002 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-15344320

RESUMO

It is the point at issue in intraspecies nuclear transfer whether quiescence is necessary for development of nuclear transfer reconstructed embryos. In the interspecies nuclear transfer, some reports have proved that quiescent cell is able to support preimplantation development of the interspecies reconstructed embryos. Are non-quiescent cells able to support preimplantation development of the interspecies reconstructed embryos? We used non-quiescent somatic cells from C57BL/6 mice and giant pandas as donors to transfer into enucleated rabbit oocytes. After electrofusion (the electrofusion rates were 62.2% and 71.6%, respectively) and electrical activation, 5.1% of those mouse-rabbit reconstructed embryos developed to blastocyst in vitro, and 4.2% of panda-rabbit reconstructed embryos developed to blastocyst after transferring into ligated rabbit oviduct. These results indicate that non-quiescent cell from C57BL/6 mouse and giant panda could be dedifferentiated in enucleated rabbit oocytes and support early embryo development.


Assuntos
Técnicas de Transferência Nuclear , Animais , Blastocisto/citologia , Blastocisto/metabolismo , Células Cultivadas , Transferência Embrionária/métodos , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Oócitos/metabolismo , Coelhos , Ursidae
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