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Therapeutic effects of revascularisation on the healing of free bone grafts in dogs
2020
Zheng, Jia-San | Ruan, Hong-Ri | Shuang-Qiu, | Jing-Nie, | Hou, Kai-Wen | Rui-Wu,
The therapeutic effect of subcutaneous embedding and revascularisation on the repair of canine bone defects caused by open fracture was examined. A total of 12 adult beagle dogs were randomly split into a control group (group C) and a test group (group T). A section of the radius was removed from each dog under general anaesthesia and the deficit supported by an orthopaedic implant. Group T had the section surgically implanted next to the blood vessel–rich saphenous vein and Group C had it cryopreserved at −80°C. After eight weeks, the bone was surgically implanted back into the matching radial deficit. Bone healing was evaluated by gross morphological and X-ray examinations, post-mortem histology, and successive blood measurements of key bone biochemical markers. At 12 weeks, the bone healing boundary was disappearing more quickly in group T dogs than in their group C counterparts. X-ray and histological examinations showed that the cortical repair of group T subjects was complete and the bony plate arrangement was more regular than that in group C. The levels of bone biochemical markers also proved that the healing state of group T was better. The results showed that the degree of healing, osteoclast activity, and bone formation status of group T were better than those of group C, proving that the vascularised bone graft had a significantly shorter healing time than the cryopreserved bone graft.
Показать больше [+] Меньше [-]Effect of extender supplementation with low-molecular-weight antioxidants on selected quality parameters of cryopreserved canine spermatozoa
2018
Lecewicz, Marek | Strzeżek, Rafał | Kordan, Władysław | Majewska, Anna
Introduction The addition of low-molecular-weight antioxidants during the freezing process improves post-thaw sperm quality. The high antioxidant potential of cryopreserved semen could have a positive effect on the motility, viability, and energy status of sperm cells and their ability to bind to the zona pellucida of oocytes. The aim of the study was to determine the effects of different concentrations and combinations of vitamins E and C in a semen extender on selected quality parameters of frozen-thawed canine spermatozoa. Material and Methods The experimental material was the semen of four mixed-breed dogs. Sperm viability (motility, plasma membrane integrity, and mitochondrial function) was examined at 0, 60, and 120 min in semen samples supplemented with the extender and in the controls. Results Combined supplementation with vitamins C + E at a concentration of 200 + 200 μM /1 × 10⁹ spermatozoa had the most profound effect on total sperm motility, linear motility, and the percentage of spermatozoa with intact plasma membrane and active mitochondria. Conclusion The synergistic activity of vitamins E and C had a more beneficial influence on the quality of frozen–thawed sperm than these non-enzymatic antioxidants applied separately.
Показать больше [+] Меньше [-]Effect of extender supplementation with low-molecular-weight antioxidants on selected quality parameters of cryopreserved canine spermatozoa
2018
Lecewicz Marek | Strzeżek Rafał | Kordan Władysław | Majewska Anna
Introduction The addition of low-molecular-weight antioxidants during the freezing process improves post-thaw sperm quality. The high antioxidant potential of cryopreserved semen could have a positive effect on the motility, viability, and energy status of sperm cells and their ability to bind to the zona pellucida of oocytes. The aim of the study was to determine the effects of different concentrations and combinations of vitamins E and C in a semen extender on selected quality parameters of frozen-thawed canine spermatozoa.
Показать больше [+] Меньше [-]ARTs in wild felid conservation programmes in Poland and in the world
2019
Kochan, Joanna | Niżański, Wojciech | Moreira, Nei | Cubas, Zalmir Silvino | Nowak, Agnieszka | Prochowska, Sylwia | Partyka, Agnieszka | Młodawska, Wiesława | Skotnicki, Józef
With the exception of the domestic cat, all felid species (Felidae) are currently threatened with extinction in their natural habitat. To develop effective and optimal wild cat conservation programmes with assisted reproductive technology (ART) it is necessary to combine advances from different disciplines of science, starting from the biology of the species, through research into the population and habitat, assisted reproductive technologies, establishment of gene banks, developing bioinformatic systems, and ending with biodiversity and endangered species management. In the last few years knowledge of felid reproduction has expanded considerably thanks to comparative studies utilising the domestic cat as a research model for endangered wild cats. Basic reproductive techniques utilised in both domestic cat breeding and rescuing wild felid populations that are threatened with extinction include semen collection and cryopreservation, artificial insemination, oocyte collection, in vitro maturation, in vitro fertilisation, somatic cloning, and embryo transfer. The main directions in which assisted reproductive technologies are being developed in wild cat conservation implementations and the contribution of Polish research centres in advancing these methods are presented.
Показать больше [+] Меньше [-]Studies on fresh milt parameters and cryopreservation of spermatozoa of endangered, golden mahseer, tor putitora (hamilton)
2023
Ravindragouda Patil | Wazir Singh Lakra | Shrinivas Jahageerdar | Gopal Krishna | Asim Kumar Pal
Physico-chemical parameters of fresh milt and mitochondrial activity of fresh spermatozoa of the endangered golden mahseer, Tor putitora (Hamilton) were investigated. Cryopreservation and fertility evaluation of cryopreserved-thawed spermatozoa of T. putitora were carried out. The concentration of spermatozoa and the spermatocrit values of the fresh milt were estimated to be 3.96±0.12 x 107 spermatozoa/ml and 70.00±1.53% respectively. The motility percentage of spermatozoa in the fresh milt was estimated to be 94.84±0.43. The elemental composition analysis revealed that the concentration of K+ was higher i.e., 14.13±0.32 mg/l when compared to that of Na+, Ca+, Mg+ and Zn+. The concentration of total reducing sugars and total proteins were estimated to be 51.79±0.47mg/100 ml and 40.57±0.75 mg/100ml respectively. The absorbance value of the fresh spermatozoa in Sperm Mitochnodrial Activity Index (SMAI) assessment by Nitro Blue Tetrazolium (NBT) assay was estimated to be 0.33±0.012. The optimum sperm: egg ratio was estimated to be 3.96 ±0.12 x 104+ no./egg. Hatching percentage of 45.97±1.72 was recorded for the cryopreserved-thawed spermatozoa while the fresh milt control recorded a hatching percentage of 73.10±0.82.
Показать больше [+] Меньше [-]Supplementation of cryoprotective extender with resveratrol decreases apoptosis index and reactive oxygen species levels in post-thaw dog sperm
2021
Bang, S.G. | Tanga, B.M. | Qamar, A.Y. | Fang, X. | Seong, G.H. | Nabeel, A.H.T. | Yu, I.J. | Cho, J.K.
Resveratrol (RSV, 3,5,4′-trihydroxytrans-stilbene) protects sperm from cryo-induced damage in various animal and human species. In this study, we aimed to assess the effect of dog sperm cryoprotective extender containing RSV on the quality of post-thaw dog sperm. Sperm were collected from 4 Beagles and supplemented with different concentrations of RSV (0, 100, 200, and 400 µM). After thawing, apoptosis index, and reactive oxygen species (ROS) levels were assessed to determine post-thaw sperm quality. Dog sperm cryopreserved with 400 µM RSV showed significant improvement in post-thaw sperm quality with lower apoptosis index and ROS levels (p < 0.05). Our results showed that the supplementation of dog sperm cryoprotective extender with RSV at a concentration of 400 µM improved the post-thaw dog sperm quality in the term of sperm ROS production and apoptosis. In addition, we emphasize the necessity of testing the ROS levels and apoptosis index using flow cytometry to determine the quality of post-thaw semen.
Показать больше [+] Меньше [-]Effects of enzyme and cryoprotectant concentrations on yield of equine adipose-derived multipotent stromal cells
2018
Duan, Wei | Lopez, Mandi J.
OBJECTIVE To evaluate effects of various concentrations of collagenase and dimethyl sulfoxide (DMSO) on yield of equine adipose-derived multipotent stromal cells (ASCs) before and after cryopreservation. SAMPLE Supragluteal subcutaneous adipose tissue from 7 Thoroughbreds. PROCEDURES Tissues were incubated with digests containing 0.1%, 0.05%, or 0.025% type I collagenase. Part of each resulting stromal vascular fraction was cryopreserved in 80% fetal bovine serum (FBS), 10% DMSO, and 10% Dulbecco modified Eagle medium F-12 and in 95% FBS and 5% DMSO. Half of each fresh and cryopreserved heterogeneous cell population was not immunophenotyped (unsorted) or was immunophenotyped for CD44+, CD105+, and major histocompatability complex class II (MHCII; CD44+-CD105+-MHCII+ cells and CD44+-CD105+-MHCII− cells). Cell proliferation (cell viability assay), plasticity (CFU frequency), and lineage-specific target gene and oncogene expression (reverse transcriptase PCR assays) were determined in passage 1 cells before and after culture in induction media. RESULTS Digestion with 0.1% collagenase yielded the highest number of nucleated cells. Cell surface marker expression and proliferation rate were not affected by collagenase concentration. Cryopreservation reduced cell expansion rate and CD44+-CD105+-MHCII− CFUs; it also reduced osteogenic plasticity of unsorted cells. However, effects appeared to be unrelated to DMSO concentrations. There were also variable effects on primordial gene expression among cell isolates. CONCLUSIONS AND CLINICAL RELEVANCE Results supported the use of 0.1% collagenase in an adipose tissue digest and 5% DMSO in cryopreservation medium for isolation and cryopreservation, respectively, of equine ASCs. These results may be used as guidelines for standardization of isolation and cryopreservation procedures for equine ASCs.
Показать больше [+] Меньше [-]A study of the bone marrow derived mesenchymal stromal cells in rats – proliferation and immunophynotypic markers
2018
Mauida, F. Hasoon, | Buktiar, Nader | Majed, H. Mohammed
Mesenchymal stem cells derived from bone marrow (BM-MSCs) havethe ability to differentiate into multiple cell lineages. Although the cultivation of these cells has led to a number of characterisation studies, some significant morphological and immunohistochemical properties are still lacking. In this study, isolation of BM-MSCs, morphological features, cell viability, immunophenotypic properties and cryopreservation of BM-MSCs wereexamined in detail. The results demonstrate that the cells isolated from BM-MSCs were plastic adherent and had fibroblastic spindle shape after three passages and get confluent monolayer cells 70-80% after 4-7 days post-subculture. Based on the cell viability analysis, the BM-MSCs showed an increase in cell viability starting from passage 1 until passage 10. Immunophenotypic analysis demonstrated that BM-MSCs were positivefor CD44 and CD105 and negative for CD34. Functional analysis of cryopreservation of BM-MSCs from P6 after 6 months expressed good proliferation rate and cell viability.
Показать больше [+] Меньше [-]Comparison of the effects of glycerol, dimethyl sulfoxide, and hydroxyethyl starch solutions for cryopreservation of avian red blood cells
2015
Graham, Jennifer E. | Meola, Dawn M. | Kini, Nisha R. | Hoffman, Andrew M.
OBJECTIVE To compare effectiveness of glycerol, dimethyl sulfoxide (DMSO), and hydroxyethyl starch (HES) solutions for cryopreservation of avian RBCs. SAMPLE RBCs from 12 healthy Ameraucana hens (Gallus gallus domesticus). PROCEDURES RBCs were stored in 20% (wt/vol) glycerol, 10% (wt/vol) DMSO freezing medium, or various concentrations of HES solution (7.5%, 11.5%, and 20% [wt/vol]) and frozen for 2 months in liquid nitrogen. Cells were then thawed and evaluated by use of cell recovery and saline stability tests, cell staining (7-aminoactinomycin D and annexin V) and flow cytometry, and scanning electron microscopy. RESULTS Percentage of RBCs recovered was highest for 20% glycerol solution (mean ± SE, 99.71 ± 0.04%) and did not differ significantly from the value for 7.5% HES solution (99.57 ± 0.04%). Mean saline stability of RBCs was highest for 10% DMSO (96.11 ± 0.25%) and did not differ significantly from the value for 20% HES solution (95.74 ± 0.25%). Percentages of cells with 7-aminoactinomycin D staining but without annexin V staining (indicating necrosis or late apoptosis) were lowest for 10% DMSO freezing medium (3%) and 20% glycerol solution (1%) and highest for all HES concentrations (60% to 80%). Scanning electron microscopy revealed severe membrane changes in RBCs cryopreserved in 20% HES solution, compared with membrane appearance in freshly harvested RBCs and RBCs cryopreserved in 10% DMSO freezing medium. CONCLUSIONS AND CLINICAL RELEVANCE Cryopreservation of avian RBCs with HES solution, regardless of HES concentration, resulted in greater degrees of apoptosis and cell death than did cryopreservation with other media. Transfusion with RBCs cryopreserved in HES solution may result in posttransfusion hemolysis in birds.
Показать больше [+] Меньше [-]Comparing effects of freezing at -196 °C and -20 °C on the viability of mastitis pathogens
2012
Inge-Marie Petzer | Joanne Karzis | Theodorus J. van der Schans | Johanna C. Watermeyer | Norman Mitchell-Innes | Stephanie Eloff | Geoffrey T. Fosgate
The aim of this study was to compare the effects of cryopreservation at approximately -196 °C in liquid nitrogen (N) and freezing at approximately -20 °C in a freezer, on the viability and survival of eight different mastitogenic bacteria inoculated in milk. Bacteria were frozen at approximately -20 °C in a freezer and cryopreserved at approximately -196 °C in liquid nitrogen. An effective preservation method was needed for follow-up samples from cows identified in the South African National Milk Recording Scheme (NMRS) with somatic cell counts above 250 000 cells/mL milk. The organisation responsible for sample collection of the NMRS milk samples also provides producers with liquid nitrogen for their semen flasks at the collection sites. This existing mode of storage and transport could therefore be utilised. Ten samples of each organism were thawed and cultured bi-weekly until week 18 for both temperature treatments. An additional sampling was performed at week 30 for samples frozen at approximately -20 °C. Freezing and cryopreservation did not impair subsequent isolation of Streptococcus dysgalactiae, Streptococcus uberis, Enterococcus faecalis, Staphylococcus aureus (STH) (phage type lytic group III) or Sta. aureus (STA) (phage typed, other than lytic group III). Survival was indicated by the isolation of bacteria from samples, and viability by the strength of growth of the bacteria isolated. The survival of Streptococcus agalactiae decreased after week 12 and Escherichia coli after week 16 of freezing, but both organisms survived under cryogenic preservation until week 18. Coagulase-negative staphylococci survived until week 18 for both freezing and cryogenic preservation. Both storage methods could thus contribute to the improvement of a pro-active approach towards udder health management in South African dairy herds.
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