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1.
Animals (Basel) ; 12(22)2022 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-36428365

RESUMEN

Pangolins are one of the world's most trafficked mammals. Since pangolins are highly adapted to ants and termites, they are important for controlling forest termite infestations. In addition to their ecological value, pangolins have economic and medicinal value. Currently, poaching and habitat destruction have radically reduced the number of pangolins, and Manis pentadactyla, Manis javanica, and Manis culionensis are now considered the most threatened pangolin species. In addition to the control of hunting and illegal trade, ex situ breeding is also a useful conservation method. However, many technical obstacles still limit the success of ex situ pangolin breeding. The special feeding traits of pangolins require a diet that meets nutritional and ethological needs. Based on the existing literature and practical experience, this review aims to compare the natural diet and successful diet in the human care of pangolins, to outline the key factors of successful ex situ maintenance from a dietary perspective, and the strategies to improve their conservation success in animal care centers and in the wild. The type of food used in successful pangolin protection agencies is quite variable in nutritional composition. In the diet of pangolins in the wild, the nutrient profile of different species of termites and ants and even the same species of termites and ants but different types (queens, soldiers, etc.) also displays differences. The crude protein content of some ants is higher than that of other foods, such as eggs, milk, and common cat food. The mineral and vitamin concentrations of ants also exceed many common food items, such as oil, meat, and eggs. However, not much is known about the bioavailability of minerals from ants and termites. Based on comparisons between foods, it is clear that the main difference between diets in the wild and in human care of pangolins is that the latter contains fewer insects and vitamins, such as vitamin E, vitamin A, and vitamin B2, and more carbohydrates and non-protein substances than the former. Although many successful dietary formulae have been developed, the pangolin's nutritional needs are still less well studied. A diet with the nutrient concentrations observed in the wild may add to successful ex situ conservation.

2.
Virus Evol ; 6(1): veaa020, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32296543

RESUMEN

Epizootic pathogens pose a major threat to many wildlife species, particularly in the context of rapidly changing environments. Pangolins (order Pholidota) are highly threatened mammals, in large part due to the trade in illegal wildlife. During July to August 2018 four sick wild pangolins (three Manis javanica and one Manis pentadactyla) exhibiting a variety of clinical symptoms were rescued by the Jinhua Wildlife Protection Station in Zhejiang province, China. Although three of these animals died, fortunately one recovered after 2 weeks of symptomatic treatment. Using meta-transcriptomics combined with reverse transcription polymerase chain reaction (RT-PCR), we identified two novel RNA viruses in two of the dead pangolins. Genomic analysis revealed that these viruses were most closely related to pestiviruses and coltiviruses, although still highly genetically distinct, with more than 48 and 25 per cent sequence divergence at the amino acid level, respectively. We named these Dongyang pangolin virus (DYPV) and Lishui pangolin virus (LSPV) based on the sampling site and hosts. Although coltiviruses (LSPV) are known to be transmitted by ticks, we found no evidence of LSPV in ticks sampled close to where the pangolins were collected. In addition, although DYPV was present in nymph ticks (Amblyomma javanense) collected from a diseased pangolin, they were not found in the local tick population. Epidemiological investigation revealed that both novel viruses might have been imported following the illegal international trade of pangolins. Hence, these data indicate that illegal wildlife trafficking not only threatens the status of pangolin populations, but may also spread epizootic pathogens.

3.
Ying Yong Sheng Tai Xue Bao ; 26(11): 3516-22, 2015 Nov.
Artículo en Chino | MEDLINE | ID: mdl-26915211

RESUMEN

Cladocera of 17 sampling locations in Bosten Lake were investigated 11 times from 2010 to 2013. Their community structure and succession dynamics were elaborated, and their responses to environment factors were analyzed. The results showed that a total of 14 species were identified and 3 of them were the dominant species. Compared with history data, species preferring oligotrophic conditions were decreasing or even disappeared, and species preferring eutrophic conditions had occupied the dominant position gradually. Spatial and temporal distribution of Cladocera densities changed greatly. Densities of the 17 sampling locations varied from 0-567.0 ind · L(-1) with an average of 30.0 ind · L(-1). Annual density of 2011 was the highest (82.5 ind · L(-1)), and then decreased year by year. Horizontal distribution of Cladocera showed a significant difference, and it was higher in shallow water area along the coast than in deep water area in the center. Temperature was the main ecological factor affecting the Cladocera community. Species distribution changed with water depth, and Daphnia longispina was common in the deep water while Bosmina longirostris was common in shallow water. Food limitation and fish predation might be the important reason that caused the variation of community structure.


Asunto(s)
Cladóceros/clasificación , Ecosistema , Lagos , Animales , Biota , Daphnia , Peces , Temperatura
4.
Cell Transplant ; 16(6): 579-85, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17912949

RESUMEN

Human mesenchymal stem cells (MSCs) are multipotential and are detected in bone marrow (BM), adipose tissue, placenta, and umbilical cord blood (UCB). In this study, we examined the ability of UCB-derived MSCs (UCB-MSCs) to support ex vivo expansion of hematopoietic stem/progenitor cells (HSPCs) from UCB and the engraftment of expanded HSPCs in NOD/SCID mice. The result showed that UCB-MSCs supported the proliferation and differentiation of CD34+ cells in vitro. The number of expanded total nucleated cells (TNCs) in MSC-based culture was twofold higher than cultures without MSC (control cultures). UCB-MSCs increased the expansion capabilities of CD34+ cells, long-term culture-initiating cells (LTC-ICs), granulocyte-macrophage colony-forming cells (GM-CFCs), and high proliferative potential colony-forming cells (HPP-CFCs) compared to control cultures. The expanded HSPCs were transplanted into lethally irradiated NOD/SCID mice to assess the effects of expanded cells on hematopoietic recovery. The number of white blood cells (WBCs) in the peripheral blood of mice transplanted with expanded cells from both the MSC-based and control cultures returned to pretreatment levels at day 25 posttransplant and then decreased. The WBC levels returned to pretreatment levels again at days 45-55 posttransplant. The level of human CD45+ cell engraftment in primary recipients transplanted with expanded cells from the MSC-based cultures was significantly higher than recipients transplanted with cells from the control cultures. Serial transplantation demonstrated that the expanded cells could establish long-term engraftment of hematopoietic cells. UCB-MSCs similar to those derived from adult bone marrow may provide novel targets for cellular and gene therapy.


Asunto(s)
Antígenos CD34/análisis , Sangre Fetal/citología , Supervivencia de Injerto , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/citología , Células Madre Mesenquimatosas/citología , Adulto , Animales , Proliferación Celular , Técnicas de Cocultivo , Trasplante de Células Madre de Sangre del Cordón Umbilical , Femenino , Factores de Crecimiento de Célula Hematopoyética/farmacología , Células Madre Hematopoyéticas/fisiología , Humanos , Separación Inmunomagnética/clasificación , Inmunofenotipificación , Recuento de Leucocitos , Masculino , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/fisiología , Ratones , Ratones Endogámicos NOD , Ratones SCID , Embarazo , Quimera por Radiación , Trasplante Heterólogo
5.
Cell Physiol Biochem ; 20(1-4): 205-12, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17595529

RESUMEN

UNLABELLED: This study was supported by grants of New Ideas Capability for Backbone Teachers in Universities of Heilongjiang and of Scientific Research foundation in Qiqihar Medical College. BACKGROUND/AIMS: Ulcer recurrence and poor healing may be critically important to the development of serious gastrointestinal complications in patients with long-term non-steroid anti-inflammatory drugs (NSAIDs). The present study is to investigate the effects of aspirin on ulcer recurrence and healing quality and to explore the mechanism. METHODS: Gastric ulcers were induced with acetic acid in rats; aspirin was administrated by gavage from day 25 to day 54 after ulcer induction. The gastric juice volume, pH, gastric mucus, gastric mucosal blood flow (GMBF) and prostaglandin E(2) (PGE(2)) were measured. The mRNA transcription of cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) were analyzed with RT-PCR and protein expression with Western blot. RESULTS: The gastric juice volume was significantly increased in aspirin group compared with those of fasting or saline control groups (P<0.01); while the pH, mucus, GMBF and PGE(2) were significantly decreased in aspirin treated rats compared with those of other two groups (P<0.01). COX-2, evaluated with mRNA and protein expression, was significantly augmented in aspirin group compared with others. The quality of ulcer healing (QOUH) in Aspirin group was poorer than that of fasting or saline control groups. CONCLUSIONS: Aspirin enhance the recurrence of gastric ulcer. The inhibition of cycloxygenase, mucus secretion and mucosal blood flow may be involved. Aspirin also impair the quality of ulcer healing.


Asunto(s)
Ácido Acético/toxicidad , Antiinflamatorios no Esteroideos/toxicidad , Aspirina/toxicidad , Úlcera Gástrica/inducido químicamente , Animales , Secuencia de Bases , Ciclooxigenasa 1/genética , Ciclooxigenasa 2/genética , Cartilla de ADN/genética , Dinoprostona/metabolismo , Jugo Gástrico/metabolismo , Mucosa Gástrica/irrigación sanguínea , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/patología , Concentración de Iones de Hidrógeno , Masculino , Proteínas de la Membrana/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Recurrencia , Flujo Sanguíneo Regional/efectos de los fármacos , Úlcera Gástrica/genética , Úlcera Gástrica/patología , Úlcera Gástrica/fisiopatología
6.
World J Gastroenterol ; 12(3): 393-402, 2006 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-16489638

RESUMEN

AIM: To establish a novel coculture system for ex vivo expansion of umbilical cord blood(UCB) hematopoietic progenitors using thrombopoietin (TPO)/Flt-3 ligand (FL)-transduced human marrow-derived mesenchymal stem cells (tfhMSCs) as feeder. METHODS: UCB CD34+ cells were isolated and cultured using four culture systems in serum-containing or serum-free medium. Suitable aliquots of cultured cells were used to monitor cell production, clonogenic activity, and long-term culture-initiating culture (LTC-IC) output. Finally, the severe-combined immunodeficient (SCID) mouse-repopulating cell (SRC) assay was performed to confirm ability of the cultured cells to reconstitute long-term hematopoiesis. RESULTS: There were no significant differences in the number of total nucleated cells among different culture systems in serum-containing medium during 21-d culture. However, on d 14, the outputs of CD34+ cells, CFU-C and CFU-GEMM in tfhMSCs coculture system were significantly enhanced. LTC-IC assay demonstrated that the tfhMSCs coculture system had the most powerful activity. The severe-combined immunodeficient (SCID) mouse repopulating cell (SRC) assay confirmed extensive ability of the expanded cells to reconstitute long-term hematopoiesis. Furthermore, PCR analysis demonstrated the presence of human hematopoietic cells in the bone marrow and peripheral blood cells of NOD/SCID mice. CONCLUSION: The TPO/FL-transduced hMSCs, in combination with additive cytokines, can effectively expand hematopoietic progenitors from UCB in vitro and the tfhMSCs coculture system may be a suitable system for ex vivo manipulation of primitive progenitor cells under contact culture conditions.


Asunto(s)
Antígenos CD34/metabolismo , Técnicas de Cultivo de Célula , Técnicas de Cocultivo , Sangre Fetal/citología , Células Madre Mesenquimatosas/metabolismo , Animales , Células Cultivadas , Ensayo de Unidades Formadoras de Colonias , Medio de Cultivo Libre de Suero , Citocinas/metabolismo , Humanos , Inmunofenotipificación , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Células Madre Mesenquimatosas/citología , Ratones , Ratones SCID , Trombopoyetina/genética , Trombopoyetina/metabolismo
7.
Zhonghua Xue Ye Xue Za Zhi ; 26(2): 65-8, 2005 Feb.
Artículo en Chino | MEDLINE | ID: mdl-15921619

RESUMEN

OBJECTIVE: To explore the biological characteristics of mesenchymal stem cells (MSC) derived from umbilical cord blood (UCB) and their supporting capacities in ex vivo expansion of hematopoietic stem/progenitor cells (HSPCs). METHODS: Low-density mononuclear cells (MNCs) from UCB were cultured in IMDM containing 20% FBS to form confluent adherent cells through 15 passages. Some cytokines in the conditioned medium were determined with ELISA. UCB-derived adherent cells were displayed with antibodies and analyzed with flow cytometry. The supporting capacity of UCB-derived adherent cells for ex vivo expansion of CD34(+) cells was assayed by co-culture in a two step culture. UCB-derived adherent cells were induced for chondrogenic differentiation with chondrogenic medium, and the induced cells were analyzed for the type II pro-collagen gene expression with RT-PCR. RESULTS: The mean number of adherent fibroblast like colonies derived from UCB was (3.5 +/- 0.7)/10(6) MNCs. UCB-derived MSCs could survive for at least 15 passages of expansion. In their undifferentiated status, UCB-derived MSCs were CD13(+), CD29(+), CD90(+), CD105(+), CD166(+), SH2(+), SH3(+), SH4(+), CD45(-), CD34(-), and CD14(-). Stem cell factor (SCF), interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) could be detected in the supernatant of the cultures. The MSCs cultured in chondrogenic media could differentiate into chondrogenic cells and express type II pro-collagen mRNA. UCB-derived MSCs could support the proliferation and differentiation of UCB CD34(+) cells in vitro. CONCLUSION: UCB-derived MSCs are similar to those derived from adult bone marrow and can support the proliferation of hematopoietic stem/progenitor cells.


Asunto(s)
Proliferación Celular , Sangre Fetal/citología , Células Madre Hematopoyéticas/citología , Células Madre Mesenquimatosas/citología , Antígenos CD34/metabolismo , Adhesión Celular , Diferenciación Celular , Células Cultivadas , Técnicas de Cocultivo , Colágeno Tipo II/genética , Citocinas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Expresión Génica , Células Madre Hematopoyéticas/metabolismo , Humanos , Células Madre Mesenquimatosas/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
8.
Haematologica ; 89(7): 837-44, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15257936

RESUMEN

BACKGROUND AND OBJECTIVES: Human mesenchymal stem/progenitor cells (MSPC) ar pluripotent, being the precursors for marrow stroma, bone, cartilage, muscle and connective tissues. Although the presence of hematopoietic stem/progenitor cells (HSPC) in umbilical cord blood (UCB) is well known, that of MSPC has been not fully evaluated. DESIGN AND METHODS: In this study, we examined the immunophenotype, the supporting function in relation to ex vivo expansion of hematopoietic stem progenitor cells and the chondrogenic differentiation of cultured cells with characteristics of MSPC from UCB. When UCB nucleated cells were isolated and 107 cells cultured in IMDM with 20% fetal bovine serum, the mean number of adherent fibroblastlike colonies was 3.5+/-0.7/10(6) monuclear cells. RESULTS: UCB-derived MSPC could be expanded for at least 15 passages. In their undifferentiated state, UCB-derived MSPC were CD13(+), CD29(+), CD90(+), CD105(+), CD166(+), SH2(+), SH3(+), SH4(+), CD45(-), CD34(-), and CD14(-); they produced stem cell factor, interleukin 6 and tumor necrosis factor alpha. UCB-derived MSPC cultured in chondrogenic media differentiated into chondrogenic cells. UCB-derived MSPC supported the proliferation and differentiation of CD34(+) cells from UCB in vitro. INTERPRETATION AND CONCLUSIONS: UCB-derived MSPC have the potential to support ex vivo expansion of HSPC and chondrogenic differentiation. UCB should not be regarded as medical waste. It can serve as an alternative source of mesenchymal stem cells and may provide a unique source of fetal cells for cellular and gene therapy.


Asunto(s)
Antígenos CD34/sangre , Cartílago/citología , Sangre Fetal/citología , Células Madre Hematopoyéticas/inmunología , Células Madre Mesenquimatosas/citología , Células Madre/citología , Adulto , Adhesión Celular , Diferenciación Celular , Células Cultivadas , Condrogénesis , Femenino , Fibroblastos/citología , Humanos , Inmunofenotipificación
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