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1.
Molecules ; 26(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200394

RESUMO

Zinc is an effective anti-inflammatory and antioxidant trace element. The aim of this study was to analyse the protective effect of zinc and zinc-prolactin systems as additives of preservation solutions in the prevention of nephron damage caused during ischemia. The study used a model for storing isolated porcine kidneys in Biolasol®. The solution was modified with the addition of Zn at a dose of 1 µg/L and Zn: 1 µg/L with prolactin (PRL): 0.1 µg/L. After 2 h and 48 h of storage, the levels of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, sodium, potassium, creatinine and total protein were determined. Zinc added to the Biolasol® composition at a dose of 1 µg/L showed minor effectiveness in the protection of nephrons. In turn, Zn2+ added to Biolasol + PRL (PRL: 0.1 µg/L) acted as a prolactin inhibitor. We do not recommend the addition of Zn(II) (1 µg/L) and Zn(II) (1 µg/L) + PRL (0.1 µg/L) to the Biolasol solution.


Assuntos
Isquemia/metabolismo , Rim/metabolismo , Prolactina/metabolismo , Zinco/metabolismo , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Creatinina/metabolismo , Criopreservação/métodos , L-Lactato Desidrogenase/metabolismo , Preservação de Órgãos/métodos , Perfusão/métodos , Potássio/metabolismo , Sódio/metabolismo , Suínos
2.
Clin Ter ; 172(4): 358-362, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34247219

RESUMO

Abstract: The paper addresses the issue of the legality and ethical admissi-bility of invasive experiments on embryos and the correlated one of the degree of legal protection and dignity to be recognized for human embryos, particularly in light of the growing importance that scientific research on embryonic stem cells has been gaining from the clinical and biomedical standpoints in the therapeutic treatments of diseases so far considered incurable, in the interest of public health. Furthermore, the issue of experimentation on cryopreserved supernumerary human embryos is still extremely polarizing, which makes it harder to arrive at shared solutions. The author hopes for a broad-ranging debate at the international level, for the ultimate purpose of achieving shared regulatory frameworks.


Assuntos
Criopreservação/ética , Criopreservação/métodos , Pesquisas com Embriões/ética , Pesquisas com Embriões/legislação & jurisprudência , Embrião de Mamíferos , Princípios Morais , Valor da Vida , Humanos
3.
Ceska Gynekol ; 86(3): 156-162, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34167307

RESUMO

OBJECTIVE: Sperm cryopreservation before gonadotoxic treatment is the basic and mos teffective method of preserving reproduction, which can be used during adolescence. The communication summarizes 26 years of experience in the operation of an oncological sperm bank, analyzes spermiograms of oncological patients, assesses the relationship between sperm pathology and diagnosis, and determines the number of deaths and the use of frozen sperm. METHODS: During the existence of CAR 01 (assisted reproduction center), more than 50,000 spermiograms were performed. From January 1995 to December 2020, a total of 24,729 men were examined within the sperm bank, of which 1,448 (5.9%) had an oncological diagnosis. The spermiograms were evaluated according to current WHO (World Health Organization) manuals. Cryopreservation of sperm has undergone a major development. The rules for the storage of frozen cells have been laid down by Act No. 296/2008 Coll. since 2008. In 2019, the methodology "Cryopreservation of reproductive cells and tissues in patients before cancer treatment" was updated. In all cases, the standard thawing technique was used. The sperms were processed by the swim-up method. As part of the treatment with assisted reproduction methods, oocytes were fertilized by the ICSI (intracytoplasmatic sperm injection) micromanipulation technique. RESULTS: Out of 1,448 examined spermiograms in men with oncological diagnoses, testicular cancer was present in 43.7% of patients and malignant diseases of lymphatic and hematopoietic tissue were found in 24.1%, of which 70,1% included Hodgkin's lymphomas and 29,9% were non-Hodgkin's lymphomas. Leukemia was found in 7.9%, bone and cartilage cancers in 6.8%. The age of the clients of the whole group ranged from 13 to 64 years (27.2 ± 6.8 years). A total of 38.3% of men had normozoospermia, 54.2% of spermiograms showed pathological findings in 1 to 3 evaluated parameters and 7.5% of patients had azoospermia. Severe asthenozoospermia (mobility ≤ 10%) was detected in 57.2% of men and severe oligozoospermia (concentration ≤ 1 × 106 mm3) in 22.3% of patients. The lowest values of the spermiogram were found in men with testicular cancer; the best values were seen in CNS (central nervous system) cancers. The cryopreservation of sperm was performed in 1,340 cases (92.5%). So far, a total of 160 men (11.9%) have used frozen sperm, of which 6.2% in our center. In these 83 cases, the ICSI technique was always used, 38 clinical pregnancies (45.8%) and 32 births were achieved. We have registered 424 completed storages of semen (31.6%), of which 148 (11.0% of all oncology patients) were made due to death and the others at patients' request. Using the sperm of the dead is a specific issue. CONCLUSION: In cancer patients, sperm pathologies occur in high percentage. The lowest spermiogram values were found in men with testicular cancer. It is necessary to take into account long-term storage and fertilization by micromanipulation methods. The number of men who die is significantly higher than the number of those who use sperm to treat infertility. Cryopreservation of sperm should be offered to each patient prior to the therapy leading to the destruction of spermatogenesis.


Assuntos
Neoplasias Testiculares , Adolescente , Adulto , Criopreservação , República Tcheca , Feminino , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Espermatozoides , Neoplasias Testiculares/terapia , Adulto Jovem
4.
Methods Mol Biol ; 2276: 259-270, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34060048

RESUMO

Mitochondrial dysfunction contributes to various injuries and diseases. A mechanistic understanding of how dysfunctional mitochondria modulates metabolism is of paramount importance. Three-dimensional (3D) optical cryo-imager is a custom-designed device that can quantify the volumetric bioenergetics of organs in small animal models. The instrument captures the autofluorescence of bioenergetics indices (NADH and FAD) from tissues at cryogenic temperature. The quantified redox ratio (NADH/FAD) is used as an optical indicator of mitochondrial redox state.


Assuntos
Flavina-Adenina Dinucleotídeo/análise , Imageamento Tridimensional/métodos , Rim/química , Mitocôndrias/química , NAD/análise , Imagem Óptica/métodos , Animais , Criopreservação , Metabolismo Energético , Flavina-Adenina Dinucleotídeo/metabolismo , Secções Congeladas , Rim/metabolismo , Rim/patologia , Mitocôndrias/metabolismo , Mitocôndrias/patologia , NAD/metabolismo , Oxirredução
6.
Nat Protoc ; 16(7): 3596-3624, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34172975

RESUMO

Deaminase fused-Cas9 base editing technologies have enabled precise single-nucleotide genomic editing without the need for the introduction of damaging double-stranded breaks and inefficient homology-directed repair. However, current methods to isolate base-edited cell populations are ineffective, especially when utilized with human pluripotent stem cells, a cell type resistant to genome modification. Here, we outline a series of methods that employ transient reporters of editing enrichment (TREE) to facilitate the highly efficient single-base editing of human cells at precise genomic loci. Briefly, these transient reporters of editing enrichment based methods employ a transient episomal fluorescent reporter that allows for the real-time, flow-cytometry-based enrichment of cells that have had single nucleotide changes at precise genomic locations. This protocol details how these approaches can enable the rapid (~3-4 weeks) and efficient (clonal editing efficiencies >80%) generation of biallelic or multiplexed edited isogenic hPSC lines using adenosine and cytosine base editors.


Assuntos
Adenosina/metabolismo , Citosina/metabolismo , Edição de Genes/métodos , Genes Reporter , Células-Tronco Pluripotentes Induzidas/metabolismo , Sequência de Bases , Células Clonais , Criopreservação , Citometria de Fluxo , Humanos , Plasmídeos/genética , RNA Guia/metabolismo , Reprodutibilidade dos Testes , Análise de Célula Única , Transfecção
7.
Int J Mol Sci ; 22(11)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34072153

RESUMO

Preclinical studies have shown that postconditioning with hydrogen sulfide (H2S) exerts cardioprotective effects against myocardial ischemia-reperfusion injury (IRI). The aim of this study was to appraise the current evidence of the cardioprotective effects of H2S against IRI in order to explore the future implementation of H2S in clinical cardiac transplantation. The current literature on H2S postconditioning in the setting of global myocardial ischemia was systematically reviewed and analyzed, performing meta-analyses. A literature search of the electronic databases Medline, Embase and Cinahl identified 1835 studies that were subjected to our pre-defined inclusion criteria. Sixteen studies were considered eligible for inclusion. Postconditioning with H2S showed significant robust effects with regard to limiting infarct size (standardized mean difference (SMD) = -4.12, 95% CI [-5.53--2.71], p < 0.00001). Furthermore, H2S postconditioning consistently resulted in a significantly lower release of cardiac injury markers, lower levels of oxidative stress and improved cardiac function. Postconditioning with slow-releasing H2S donors offers a valuable opportunity for novel therapies within cardiac preservation for transplantation. Before clinical implication, studies evaluating the long-term effects of H2S treatment and effects of H2S treatment in large animal studies are warranted.


Assuntos
Coração , Sulfeto de Hidrogênio/farmacologia , Soluções para Preservação de Órgãos , Preservação de Órgãos , Animais , Biomarcadores , Criopreservação/métodos , Testes de Função Cardíaca , Transplante de Coração/métodos , Humanos , Pós-Condicionamento Isquêmico , Traumatismo por Reperfusão Miocárdica/diagnóstico , Traumatismo por Reperfusão Miocárdica/etiologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Preservação de Órgãos/métodos , Estresse Oxidativo/efeitos dos fármacos , Fatores de Risco , Doadores de Tecidos
8.
Braz J Biol ; 82: e241081, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34105654

RESUMO

This study investigated the use of melatonin to arrest the effects of apoptosis in vitrified zebrafish (D. rerio) embryos. Dechorionated embryos at 22-24 somite-stage were divided (n = 60/treatment) into a non-vitrified (Control Group, 0 M melatonin) and vitrified treatments with 0 M (T1), 1 µM (T2) and 1 mM of melatonin (T3). For vitrified treatments, a solution methanol/propylene glycol based was used and the embryos stored in -196 °C for a week. After thaw, survival rate, scanning electron microscopy, expression of anti (bcl-2) and pro-apoptotic (bax/caspase-3) genes, reactive oxygen species (ROS) formation and DNA fragmentation analyses were performed. No live embryos were obtained from vitrified treatments, observing a rapid degeneration immediately after thawing, with the vitelline layer rupture and leakage of its content, followed by breakdown of epithelial cells and melanisation of the tissue. Regarding the apoptotic process, T3 had the highest relative gene expression, for the three genes (P < 0.05) furthermore, T2 had similar expression of pro-apoptotic genes to CG (P < 0.05). ROS formation revealed that CG presented lower percentage of embryo surface area affected (3.80 ± 0.40%) (P < 0.05), in contrast, no differences were found among the other groups. T1 was most significantly (P < 0.05) damaged by DNA fragmentation. The vitrified groups with melatonin had similar damage levels of CG (P > 0.05). The inclusion of 1 µM of melatonin in the vitrifying solution, countered the effects of apoptotic process in post-thaw embryos, suggesting its utility in cryopreserving fish embryos.


Assuntos
Melatonina , Peixe-Zebra , Animais , Apoptose , Criopreservação , Melatonina/farmacologia
9.
An Acad Bras Cienc ; 93(3): e20191229, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34076181

RESUMO

To evaluate the addition of antioxidants in extenders on post-thaw bovine semen quality and in vitro embryo production efficiency. Six semen samples were collected from five Holstein bulls. In the experiment I, the samples were diluted with AndroMed® and Bovimix® and added antioxidants glutathione (1.5 and 2.5 mM) and melatonin (0.5 and 1.0 mM). In the experiment II, the best treatments obtained in experiment I were used for in vitro fecundation. Glutathione did not improve sperm viability. Melatonin had a negative effect on semen characteristics. Andromed® showed better results in sperm kinetics parameters. Bovimix® was more efficient in maintaining cell integrity parameters. Significant correlation was found between sperm kinetics parameters and between cell integrity parameters. For in vitro embryo production, after oocyte selection, maturation, fertilization and cultivation were performed using the four treatments previously evaluated. Andromed® was more efficient in the cleavage rate, no effect of the addition of glutathione. However, the addition of 2.5 mM glutathione in the Bovimix® improved the cleavage rate. There was a significant moderate correlation between cleavage rate and sperm kinetic characteristics. Glutathione did not improve sperm viability. Melatonin reduced the maintenance of sperm characteristics. Andromed® was more efficient in in vitro embryo production and no effect of glutathione was found in this extender. Addition of 2.5 mM glutathione in the Bovimix® extender provided a higher cleavage rate.


Assuntos
Análise do Sêmen , Preservação do Sêmen , Animais , Antioxidantes/farmacologia , Bovinos , Criopreservação/veterinária , Crioprotetores , Humanos , Masculino , Análise do Sêmen/veterinária , Preservação do Sêmen/veterinária , Motilidade Espermática , Espermatozoides
10.
Int J Mol Sci ; 22(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069402

RESUMO

The total damage inflicted on the liver before transplantation is associated with several surgical manipulations, such as organ recovery, washout of the graft, cold conservation in organ preservation solutions (UW, Celsior, HTK, IGL-1), and rinsing of the organ before implantation. Polyethylene glycol 35 (PEG35) is the oncotic agent present in the IGL-1 solution, which is an alternative to UW and Celsior solutions in liver clinical transplantation. In a model of cold preservation in rats (4 °C; 24 h), we evaluated the effects induced by PEG35 on detoxifying enzymes and nitric oxide, comparing IGL-1 to IGL-0 (which is the same as IGL-1 without PEG). The benefits were also assessed in a new IGL-2 solution characterized by increased concentrations of PEG35 (from 1 g/L to 5 g/L) and glutathione (from 3 mmol/L to 9 mmol/L) compared to IGL-1. We demonstrated that PEG35 promoted the mitochondrial enzyme ALDH2, and in combination with glutathione, prevented the formation of toxic aldehyde adducts (measured as 4-hydroxynonenal) and oxidized proteins (AOPP). In addition, PEG35 promoted the vasodilator factor nitric oxide, which may improve the microcirculatory disturbances in steatotic grafts during preservation and revascularization. All of these results lead to a reduction in damage inflicted on the fatty liver graft during the cold storage preservation. In this communication, we report on the benefits of IGL-2 in hypothermic static preservation, which has already been proved to confer benefits in hypothermic oxygenated dynamic preservation. Hence, the data reported here reinforce the fact that IGL-2 is a suitable alternative to be used as a unique solution/perfusate when hypothermic static and preservation strategies are used, either separately or combined, easing the logistics and avoiding the mixture of different solutions/perfusates, especially when fatty liver grafts are used. Further research regarding new therapeutic and pharmacological insights is needed to explore the underlying mitochondrial mechanisms exerted by PEG35 in static and dynamic graft preservation strategies for clinical liver transplantation purposes.


Assuntos
Transplante de Fígado/métodos , Preservação de Órgãos/métodos , Polietilenoglicóis/farmacologia , Alanina Transaminase/metabolismo , Aldeído-Desidrogenase Mitocondrial/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Criopreservação/métodos , Fígado Gorduroso/metabolismo , Glutationa/metabolismo , Fígado/citologia , Masculino , Microcirculação/efeitos dos fármacos , Mitocôndrias/metabolismo , Óxido Nítrico/metabolismo , Soluções para Preservação de Órgãos/farmacologia , Ratos , Ratos Zucker , Manejo de Espécimes/métodos
11.
Immunohematology ; 37(2): 78-83, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34170642

RESUMO

Units of red blood cell (RBC) concentrates with rare phenotypes are typically not included in method validation studies for cryopreservation processes; rather, they are reserved for patients with rare blood needs. Some rare RBC phenotypes may demonstrate membrane abnormalities, like acanthocytosis as observed for RBCs with the McLeod phenotype, and are specifically banked for these rare attributes; however, the impact that rare RBC phenotypes have on post-thaw quality has not been well studied. To evaluate how a rare RBC phenotype is affected by the cryopreservation process, 4 RBC units, cryopreserved in 1993 using manual methods, were selected for evaluation. These RBCs included one with the McLeod phenotype and three with phenotypes not known to cause significant membrane changes. Post-thaw, an altered deglycerolization protocol, implemented to reduce supernatant glycerol after cryopreservation, was used before processing RBCs on an automated closed system (ACP 215; Haemonetics, Boston, MA) to accommodate the use of a closed system cell processor not available when the RBC units were previously cryopreserved. RBC quality was tested at 24 hours, 7 days, and 14 days post-deglycerolization. Before deglycerolization, an extracted sample from the thawed glycerolized RBC unit was used to obtain genetic material for phenotype confirmation. Genotyping confirmed the McLeod phenotype. When comparing McLeod with non-McLeod units, RBCs from the McLeod donor exhibited acanthocytosis, higher rigidity, and lower morphology scores than RBCs from the non-McLeod units post-deglycerolization. Hemolysis, however, was comparable across all 4 units, meeting regulatory standards. Therefore, McLeod RBCs can withstand cryopreservation, suggesting that units from these donors, glycerolized using older methods, can be deglycerolized using the ACP 215 and stored hypothermically for 14 days. It was also determined that genotyping can be performed on non-leukocyte-reduced cryopreserved RBCs, allowing for confirmation of genetic profiles of donor units banked before the implementation of molecular methods.Units of red blood cell (RBC) concentrates with rare phenotypes are typically not included in method validation studies for cryopreservation processes; rather, they are reserved for patients with rare blood needs. Some rare RBC phenotypes may demonstrate membrane abnormalities, like acanthocytosis as observed for RBCs with the McLeod phenotype, and are specifically banked for these rare attributes; however, the impact that rare RBC phenotypes have on post-thaw quality has not been well studied. To evaluate how a rare RBC phenotype is affected by the cryopreservation process, 4 RBC units, cryopreserved in 1993 using manual methods, were selected for evaluation. These RBCs included one with the McLeod phenotype and three with phenotypes not known to cause significant membrane changes. Post-thaw, an altered deglycerolization protocol, implemented to reduce supernatant glycerol after cryopreservation, was used before processing RBCs on an automated closed system (ACP 215; Haemonetics, Boston, MA) to accommodate the use of a closed system cell processor not available when the RBC units were previously cryopreserved. RBC quality was tested at 24 hours, 7 days, and 14 days post-deglycerolization. Before deglycerolization, an extracted sample from the thawed glycerolized RBC unit was used to obtain genetic material for phenotype confirmation. Genotyping confirmed the McLeod phenotype. When comparing McLeod with non-McLeod units, RBCs from the McLeod donor exhibited acanthocytosis, higher rigidity, and lower morphology scores than RBCs from the non-McLeod units post-deglycerolization. Hemolysis, however, was comparable across all 4 units, meeting regulatory standards. Therefore, McLeod RBCs can withstand cryopreservation, suggesting that units from these donors, glycerolized using older methods, can be deglycerolized using the ACP 215 and stored hypothermically for 14 days. It was also determined that genotyping can be performed on non-leukocyte­reduced cryopreserved RBCs, allowing for confirmation of genetic profiles of donor units banked before the implementation of molecular methods.


Assuntos
Preservação de Sangue , Criopreservação , Eritrócitos , Glicerol , Humanos
13.
Curr Protoc ; 1(5): e123, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33950578

RESUMO

Fetal human neural stem cells (fhNSC) are of considerable interest as potential regenerative therapies for neuronal or glial degeneration or destruction resulting from genetic abnormalities, disease, or injury. Realization of this potential requires securing a supply of cells sufficient to meet the needs of transplantation, which are often tens to hundreds of millions of cells per dose. This challenge necessitates the establishment of safe and efficient cell banking protocols. Cryopreservation, involving the slow freezing or vitrification of cells, enables storage of fhNSC for prolonged periods, while maintaining their viability and multipotency required for clinical use. To optimize cryopreservation of fhNSC, attention has become focused on the composition of the medium used to effect cryopreservation by slow freezing/vitrification-i.e., the cryopreservative medium. The cryopreservative medium is typically specified as a dilution of a concentrated cryoprotectant, such as dimethylsulfoxide or glycerol, in cell culture medium that is often combined with serum or another source of necessary growth factors. The present work is devoted to a computational tool for determining the composition of a cryopreservative medium that can be combined with dissociated fhNSC resuspended in a certain volume of culture medium to achieve the criterion of stoichiometric dilution of cryoprotectant favorable to cell viability in the final mixture of cryopreservative medium and cells. © 2021 Wiley Periodicals LLC. Basic Protocol: Culture and passage of fhNSC, counting of enzymatically dissociated fhNSC, and quantitative formulation of cryomedium Alternate Protocol: Procedure when cell medium is not added to the cryomedium.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Neurais , Criopreservação , Crioprotetores/farmacologia , Humanos , Vitrificação
14.
Curr Protoc ; 1(5): e138, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34043268

RESUMO

Protocols for cryopreservation of mouse embryos and sperm are important for preserving genetically engineered mice (GEMs) used in research to study human development and diseases. Embryo cryopreservation is mainly carried out using either of two protocols: controlled gradual cooling or vitrification. Sperm cryopreservation protocols include two methodologies that are commonly referred to as JAX and CARD. Quality-control measures are necessary to ensure that GEMs are properly cryopreserved so that they can be retrieved for future use. An archiving system is also important in keeping proper records of frozen sperm and embryos. Frozen embryos and sperm are now preferred over live mice for shipping to distant locations. This article describes detailed protocols used in cryopreservation of mouse embryos and sperm, as well as their retrieval to live mice. © 2021 U.S. Government. Sperm cryopreservation Basic Protocol 1: JAX protocol for sperm cryopreservation Support Protocol 1: JAX protocol for making sperm cryopreservation medium Basic Protocol 2: JAX protocol for IVF of mouse sperm Alternate Protocol 1: Modified CARD protocol for sperm cryopreservation Support Protocol 2: CARD protocol for making sperm cryopreservation medium Alternate Protocol 2: CARD protocol for IVF of mouse sperm Embryo cryopreservation Basic Protocol 3: Cryopreserving and thawing 2-cell embryos Alternate Protocol 3: Cryopreserving and thawing 8-cell to morula-stage embryos Surgical transfer of embryos Basic Protocol 4: Infundibulum transfer of 2-cell to morula-stage embryos.


Assuntos
Criopreservação , Fertilização In Vitro , Animais , Masculino , Camundongos , Mórula , Espermatozoides , Vitrificação
15.
Transplant Proc ; 53(5): 1744-1750, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34052022

RESUMO

Islet transplantation is a promising option for the clinical treatment of insulin-dependent diabetes, but a reliable islet cryopreservation/transplantation protocol should be established to overcome the donor shortage. The current study reports that a silk fibroin (SF) sponge disk can be used as a cryodevice for vitrification of large quantity pancreatic islets and the scaffold for subsequent subrenal transplantation in a rat model. The marginal islet mass (550 islet equivalents [IEQs]) on an SF sponge disk was vitrified-warmed and transplanted beneath the kidney capsule of a streptozotocin-induced diabetic rat with or without vascular endothelial growth factor (VEGF). Subrenal transplantation (no scaffold) of 550 IEQ fresh islets and post-warm islets vitrified on a nylon mesh device resulted in achieving euglycemia of recipient rats at 60% and 0%, respectively. Transplantation of 550 IEQ islets vitrified-warmed on an SF sponge disk failed to achieve euglycemia of recipient rats (0%), but the VEGF inclusion in the SF sponge disk contributed to acquiring the euglycemic recipients (33%). All cured recipient rats regained hyperglycemia after nephrectomy, and the histopathologic analysis exhibited a well-developing blood vessel network into the islet engrafts. Thus, an SF sponge disc was successively available as the cryodevice for islet vitrification, the transporter of the angiogenic VEGF, and the scaffold for subrenal transplantation in the rat model.


Assuntos
Fibroínas/química , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/metabolismo , Engenharia Tecidual , Fator A de Crescimento do Endotélio Vascular/farmacologia , Animais , Criopreservação/instrumentação , Criopreservação/métodos , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/cirurgia , Insulina/sangue , Ilhotas Pancreáticas/efeitos dos fármacos , Masculino , Ratos
16.
Food Res Int ; 143: 110228, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33992342

RESUMO

This study investigated the potential of isochoric freezing to preserve tomatoes. Isochoric freezing is an emerging technology that preserves biological matter at subfreezing temperatures without any ice damage. Isochoric freezing was compared with freezing under isobaric conditions and with preservation techniques used in the food industry: cold storage at 10 °C and individual quick freezing (IQF). Physicochemical and nutritional properties were evaluated weekly for four weeks. Preservation under isochoric conditions maintained the mass, color, nutrient content (ascorbic acid, lycopene and phenolics) and antioxidant activity of the fresh tomatoes. Also, isochoric preservation led to minimal texture damage. In comparison, mass loss of tomatoes stored at 10 °C for 3 weeks contributed to changes in overall visual quality and firmness as well as significant losses in nutrient content. The greatest mass, texture, and nutrients losses were obtained for tomatoes subjected to IQF and isobaric freezing. The results show that isochoric freezing has the potential to preserve tomatoes while maintaining physicochemical and nutritional properties similar to those of fresh tomatoes which might find application in the commercial preservation of tomatoes.


Assuntos
Lycopersicon esculentum , Vitis , Criopreservação , Congelamento , Isocoros
19.
J Equine Vet Sci ; 101: 103393, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33993948

RESUMO

The aim of this study was to evaluate the effects of L-proline on the extender quality of frozen and post-thawed jackass semen. Jackass (n = 6) semen samples were collected and cryopreserved in gradient concentrations (0-80 mM) of L-proline in extenders; post-thawed semen samples were cultured in L-proline medium for 10 hours at 37°C. For cryopreservation experiment I, the motile parameters, mitochondrial membrane potential (MMP), and plasma membrane, acrosome, and chromatin structure integrities of post-thawed semen were assessed. For culture experiment II, additional ROS contents were analyzed after incubation. For the fertility trial, jennies (n = 135) were divided into group I (30 mM L-proline in cryopreservation extender), group II (40 mM L-proline in culture medium), and the control. Pregnancy was diagnosed using an ultrasound scanner 30 days after ovulation. The results of experiment I showed that, motile parameters and acrosome and chromatin structure integrities of groups I and 40 mM were significantly higher than the control (P < .05). MMP of group I was significantly higher than the control and 40 mM groups (P < .05). In experiment II, after 4 hours of incubation, motile parameters, MMP, and DNA integrity in group II were significantly higher than the control (P < .05). Additionally, 40 and 80 mM L-proline in culture medium significantly reduced ROS accumulation after 4 and 10 hours of incubation (P < .05). Pregnancy rates of the control and groups I and II were 28.85%, 40%, and 36.84%, respectively. In conclusion, the extenders containing 30 to 40 mM L-proline improved both qualities of frozen and post-thawed semen, and it will be a beneficial agent for donkey frozen spermatozoa or post-thawed semen storage.


Assuntos
Preservação do Sêmen , Sêmen , Animais , Criopreservação/veterinária , Crioprotetores , Equidae , Feminino , Masculino , Gravidez , Prolina/farmacologia , Preservação do Sêmen/veterinária
20.
Gan To Kagaku Ryoho ; 48(5): 639-643, 2021 May.
Artigo em Japonês | MEDLINE | ID: mdl-34006703

RESUMO

Many of oncology pharmaceuticals have ovotoxicity and/or genotoxicity. Ovarian reserve, numbers of healthy oocytes in the ovary, gradually decreases in aging, but abruptly decreases when young female cancer patients are exposed to ovotoxic pharmaceuticals. Therefore increasing number of young patients undergo fertility preservation in which oocytes or ovarian tissue are retrieved and cryopreserved before chemotherapy. The deterioration of the quality of oocytes in aging is called "oocyte aging", and the function of DNA repair in the oocytes are known to be deteriorated in aging. Similar to those from U. S. Food and Drug Administration and European Medicines Agency, labeling guidance in Japan recommends"5×T1/2 plus 6 months"of contraception period after the cessation of genotoxic pharmaceuticals, based on mouse model experiments. However, the teratogenicity of pharmaceuticals has been generally found when administered during the 4th to 10th weeks of pregnancy, and healthy children were born even when they originated from the oocytes or ovarian tissue which had been retrieved immediately after chemotherapy. We caregivers should carefully provide information to the female patients and their partners who get unexpectedly pregnant during the above‒mentioned contraception period.


Assuntos
Preservação da Fertilidade , Neoplasias , Preparações Farmacêuticas , Anticoncepção , Criopreservação , Feminino , Humanos , Japão , Neoplasias/tratamento farmacológico , Recuperação de Oócitos
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