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1.
Cryo Letters ; 44(5): 274-279, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38032307

RESUMO

BACKGROUND: N. wightii (Leguminosae) is valued as a cover crop and as a potential source of protein in food insecure countries. However, plantlet establishment is limited by physical dormancy. Our previous work has shown that exposure of N. wightii seeds to cryogenic temperatures is able to overcome physical dormancy. OBJECTIVE: The current study is an extension of that work where the field performance and nutritional composition of plants regenerated from N. wightii seeds was investigated. RESULTS: It was evident that plants regenerated from cryopreserved seeds displayed faster growth rates than those from control seeds. In addition, cryopreservation did not alter the nutritional profile of plants produced from cryo-stored seeds. CONCLUSION: Collectively, the results indicate that cryopreservation serves as a suitable strategy for the preservation of seeds of N. wightii with the added benefit of also serving as a dormancy breaking mechanism upon retrieval from cryogenic temperatures. Doi.org/10.54680/fr23510110712.


Assuntos
Criopreservação , Fabaceae , Estado Nutricional , Sementes , Temperatura
2.
Transplant Proc ; 54(6): 1471-1475, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35649967

RESUMO

BACKGROUND: Acute kidney injury (AKI) is a manifestation of SARS-CoV-2 infection. The evidence in kidney transplant (KT) is limited, as there are scarce data about the histologic features in graft biopsies of these patients. MATERIAL AND METHODS: A retrospective cohort study of KTs with SARS-CoV-2 infection from August 28, 2020, to April 23, 2021. We collected the incidence of AKI and the presence of urinary and histopathological disorders. Both groups were compared (AKI vs no AKI). Immunohistochemical and reverse transcription-polymerase chain reaction studies were performed on the anatomopathological samples. RESULTS: In our study, 72 KTs had SARS-CoV-2 infection and, among them, 27 patients (35.1%) developed AKI related to increased severity and a worse evolution of the infection, defined by a greater presence of pneumonia (P < .001), hospitalization (P < .001), admission to the intensive care unit (P < .001), the need for ventilation support (P < .001), and continuous renal replacement therapy (P < .001). In the multivariable analysis, pneumonia behaved as an independent predictor for AKI development (P = .046). No differences were observed between proteinuria a month before and after infection (P = .224). In addition, 5 patients showed microhematuria and 2 patients presented transient glycosuria without hyperglycemia. Of the 5 kidney biopsies performed, 1 biopsy (20%) showed positive reverse transcription polymerase chain reaction for SARS-CoV-2. CONCLUSIONS: AKI is a frequent and potentially serious complication in KT patients. Occasionally it could be accompanied by abnormalities in the urinary sediment. Of 5 biopsied patients, 1 patient had positive reverse transcription polymerase chain reaction in renal tissue, which suggests the systemic spread of the virus and the tropism for the renal graft.


Assuntos
Injúria Renal Aguda , COVID-19 , Transplante de Rim , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/patologia , COVID-19/complicações , Humanos , Transplante de Rim/efeitos adversos , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2
3.
Transpl Int ; 35: 10056, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35734238

RESUMO

The increasing comorbidity of kidney transplant (KT) donors make it necessary to develop scores to correctly assess the quality of kidney grafts. This study analyzes the usefulness of the preimplantation biopsy and the Kidney Donor Profile Index (KDPI) as indicators of KT survival from expanded criteria donors (ECD). Retrospective study of KT in our center between January 2010 to June 2019 who received a kidney from an ECD and underwent a preimplantation biopsy. 266 KT were included. Graft survival was categorized by KDPI quartiles: Q1 = 86%, Q2 = 95%, Q3 = 99% and Q4 = 100%. KT from KDPI Q1 presented better survival (p = 0.003) and Q4 donors had worse renal function (p = 0.018) and poorer glomerular filtration rate (3rd month; p = 0.017, 1st year; p = 0.010). KT survival was analyzed according to KDPI quartile and preimplantation biopsy score simultaneously: Q1 donors with biopsy score ≤3 had the best survival, especially comparing against Q3 with a biopsy score >3 and Q4 donors (p = 0.014). In multivariable analysis, hyaline arteriopathy, glomerulosclerosis, and KDPI Q4 were predictors for graft survival. High KDPI and a greater histological injury in the preimplantation biopsy, especially glomerular and vascular lesions, were related to a higher rate of KT loss from ECD.


Assuntos
Transplante de Rim , Biópsia , Sobrevivência de Enxerto , Humanos , Rim/patologia , Estudos Retrospectivos , Doadores de Tecidos
4.
Cryo Letters ; 43(6): 341-348, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36629829

RESUMO

BACKGROUND: Swietenia mahagoni wood is one of the most valuable in world trade and, as a result, natural populations have been decimated due to unsustainable harvesting. The decline in natural population levels is being exacerbated by climate change. In order to ensure the preservation of valuable genotypes, there is an urgent need to develop strategies to conserve the genetic diversity present within this species. At present, cryopreservation is the most viable option for the long-term storage of plant germplasm, particularly for long-lived species which are challenging to maintain in the field. OBJECTIVE: To cryopreserve intact seeds of S. mahagoni, with the dual goal of retaining the biosynthetic capacity of plants, which is critical since this species is highly valued for medicinal purposes. MATERIALS AND METHODS: Seeds at a moisture content of 6% were immersed in liquid nitrogen (LN) before warming and recovery. Plantlet establishment and growth were assessed over a period of 70 days and anthraquinone synthesis was determined in roots, stems and leaves. RESULTS: The results showed an initial lag in the germination rate of cryopreserved seeds compared with control seeds; however, this difference disappeared over time. The lag in seedling emergence observed in cryostored seeds was also evident in the plant characteristics measured following 30 days of culture when all plant parameters measured were significantly higher in plants produced from control than cryostored seeds. However, after 70 days of growth, these differences were no longer apparent. Anthraquinone levels were also initially lower (at 30 days) in plants regenerated from cryopreserved seeds than those from control seeds, however, this difference was substantially reduced by 70 days thereby indicating the ability of these plants to accumulate secondary metabolites, albeit at a reduced rate, during the early stages of development. CONCLUSION: In S. mahagoni, the delay in anthraquinone production in plants regenerated from cryostored seeds during the early stages of development may have occurred as a consequence of the preferential allocation of resources towards the initiation of recovery processes in response to the stresses imposed by cryopreservation. Once the stresses were overcome and plant growth resumed, resources could be directed to secondary processes such as anthraquinone synthesis. doi.org/10.54680/fr22610110412.


Assuntos
Criopreservação , Meliaceae , Criopreservação/métodos , Sementes/fisiologia , Plântula , Germinação/fisiologia , Plantas
5.
Transplant Proc ; 54(1): 27-31, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34876270

RESUMO

BACKGROUND: Surgical wound dehiscence (SWD) is a frequent complication after kidney transplantation (KT) but there is not enough evidence of its impact on graft survival. METHODS: A retrospective cohort study including all KT patients with SWD in our center from January 2015 to July 2020 was performed. A case-control study was performed and for each case of SWD, 2 controls were selected (2:1). To identify risk factors for SWD, a logistic regression analysis was carried out and a multivariable Cox regression was used to describe risk factors for graft survival. RESULTS: In our center, 503 KT were performed, and 39 patients presented SWD. They were older (62.1 vs 57.1 years; P = .030), most had diabetes mellitus (59% vs 28.6%; P = .002) and their body mass index was higher (31 vs 26.9 kg/m2; P < .001). In multivariable logistic regression analysis, diabetes mellitus (P = .024) and a body mass index ≥30 kg/m2 at time of transplantation (P = .018) were predictors of SWD. A higher rate of delayed graft function was described in SWD (P = .013) and it was associated with a longer hospital stay (20.9 vs 15 days; P = .004). Graft survival was lower in patients with SWD (P = .036). In multivariable Cox regression analysis, time in renal replacement therapy (P = .020) and SWD (P = .028) were predictors of shorter graft survival. CONCLUSION: SWD is a risk factor for graft survival. The presence of diabetes mellitus and a higher body mass index are predictors for the appearance of this complication.


Assuntos
Sobrevivência de Enxerto , Transplante de Rim , Estudos de Casos e Controles , Humanos , Transplante de Rim/efeitos adversos , Estudos Retrospectivos , Fatores de Risco , Deiscência da Ferida Operatória/epidemiologia , Deiscência da Ferida Operatória/etiologia
6.
Cryo Letters ; 42(2): 106-110, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33970987

RESUMO

BACKGROUND: Teramnus labialis (L.f.) Spreng is a potentially important legume species, and can be used as an animal feed and to enhance soil physicochemical characteristics. Despite the biological and agricultural importance, the low availability of seeds, their small size and the low percentage germination limit their large-scale use by farmers. We previously reported a method to cryopreserve seeds of T. labialis which also allowed for the breaking of seed dormancy. OBJECTIVE: The current study reports on the nutritional status of 5 month old field grown plants regenerated from cryostored and control seeds. MATERIALS AND METHODS: Biomass (fresh and dry mass of leaves and stems) and contents of ash, neutral detergent fiber, acid detergent fiber, lignin, cellulose, crude protein, P, Ca, Mg and K were measured. RESULTS: Seeds germinated and emerged faster following immersion in liquid nitrogen (LN) which was supported by quantitative evaluations of fresh and dry weights per m2. However, the ratio of leaf:stem mass were not altered by seed exposure to LN. CONCLUSION: The results showed that exposure of seeds to cryogenic temperatures did not alter the nutritional composition of regenerated plants.


Assuntos
Criopreservação , Fabaceae/química , Estado Nutricional , Sementes/fisiologia , Germinação , Nitrogênio
7.
Food Chem ; 344: 128603, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33234437

RESUMO

Enzymatic lipophilization is an important process to extend the use of anthocyanins in lipidic media. In this work delphinidin 3-O-sambubioside (Dp3sam) isolated from Hibiscus sabdariffa L. flower was esterified with octanoic acid using Candida antarctica lipase B. The physical-chemical properties of the new lipophilic pigment were studied by UV-vis spectroscopy. Dp3sam with chloride, acetate and formate as counter ions were employed to study the lipophilization reaction. The hydrolysis of the reagent was avoided with a formate counter ion and the expected product was achieved with a noteworthy change of solubility. 1D and 2D NMR characterization of Dp3sam-C8 confirmed that the lipophilization took place at the primary alcohol of the glucoside moiety. Overall, the Dp3sam-C8 ester presents a stabilization of the quinoidal base (blue color) at neutral or moderate alkaline pH, which foresees a potential use of this pigment as a broad kind of industries on lipo-soluble formulations.


Assuntos
Antocianinas/análise , Ácidos Graxos/metabolismo , Proteínas Fúngicas/metabolismo , Hibiscus/química , Lipase/metabolismo , Acilação , Antocianinas/isolamento & purificação , Antocianinas/metabolismo , Biocatálise , Cromatografia Líquida de Alta Pressão , Cor , Dissacarídeos/química , Hibiscus/metabolismo , Concentração de Íons de Hidrogênio , Espectrometria de Massas , Extratos Vegetais/química , Extração em Fase Sólida
8.
Cryo Letters ; 40(1): 36-44, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30955029

RESUMO

BACKGROUND: Teramnus labialis is an herbaceous legume that serves as a source of carbohydrates and proteins for animals and humans, and is valued for its nitrogen contribution to soil. The benefits of this species are, however, limited by low seed availability, small seed size and low in situ seed germination levels, due to physical dormancy. Cryostorage has been shown to be beneficial for both seed storage and breaking physical dormancy in seeds of various species. However, its potential effects on subsequent seedling emergence, plant growth and seed production need to be studied before large-scale implementation for T. labialis. OBJECTIVE: To record agricultural traits of T. labialis after seed exposure to liquid nitrogen. MATERIALS AND METHODS: Seeds were maintained at 5 degree C (control) or stored in LN before sowing. Seedling emergence percentage and traits related to plant growth and seed production were evaluated for 6 months. RESULTS: Except for seed weight, all traits differed significantly between seedlings generated from cryostored and control seeds. Except for pod number, seedling emergence and plant growth traits were enhanced by cryostorage to a greater extent than seed production traits. Cryostorage resulted in cracks and breaks in the seed coat which were absent in control seeds (scanning electron microscopy), and in breaking physical dormancy may have facilitated more rapid seedling emergence than for control seeds. CONCLUSION: Seed cryostorage enhances subsequent plant productivity in terms of growth and to a lesser extent seed production in Teramnus labialis, validating its use for commercial growth of this species.


Assuntos
Criopreservação , Fabaceae , Sementes , Germinação , Plântula
9.
Actas Dermosifiliogr (Engl Ed) ; 110(7): 590-596, 2019 Sep.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29937063

RESUMO

Primary recurrent cutaneous eosinophilic vasculitis is a rare condition characterized by pruritic, erythematous, purpuric plaques associated to edema. We compared and analyze the clinical, dermoscopic and histological features of the disease in 4 patients from our hospital and 13 patients published in the literature. Seventeen patients were included, with a median age of 56yo, a median duration of disease of 6 months. Lesions were most frequently generalized (47%) or localized in lower limbs (41%). The most frequent features were purpuric color (71%), local edema (65%), necrotizing vasculitis (94%) and eosinophil infiltration (100%) in histology. Most of the patients (82.4%) were given oral steroids with a median dose of 30mg. Primary recurrent cutaneous eosinophilic vasculitis might be an infra-diagnosed condition. The analysis of the patients allowed us to propose diagnostic criteria for the definition of this disease. We suggest a therapeutic strategy with high-potency steroids and dapsone, which might be considered as first-line treatment.


Assuntos
Dermoscopia , Eosinofilia/tratamento farmacológico , Eosinofilia/patologia , Dermatopatias Vasculares/tratamento farmacológico , Dermatopatias Vasculares/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Esteroides/uso terapêutico
11.
Cryo Letters ; 23(4): 237-44, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12391484

RESUMO

In this paper, we investigated if the differences consistently noted in survival and plantlet production between cryopreserved and non-cryopreserved, control sugarcane embryogenic calluses were related to modifications induced during cryopreservation in the structural and functional integrity of cell membranes. For this, the evolution of electrolyte leakage, lipid peroxidation products and cell membrane protein contents was measured during 5 d after cryopreservation. Differences between control and frozen calluses were observed only during the first 2 (electrolyte leakage) or 3 d (lipid peroxidation products and membrane protein content) after freezing. It was not possible to link these differences with the differences noted in survival and plant production between control and cryopreserved calluses. Additional studies are thus needed to elucidate which biochemical factors, linked to survival and plantlet regeneration, are affected by cryopreservation.


Assuntos
Membrana Celular/fisiologia , Criopreservação , Saccharum/citologia , Humanos , Malondialdeído/análise , Saccharum/embriologia
12.
Cryo Letters ; 23(1): 21-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11912504

RESUMO

This study compared the field performance of sugarcane plants originating from three different sources: control, non-cryopreserved embryogenic calluses, cryopreserved embryogenic calluses and macropropagated material of the same commercial hybrid. Several agronomic traits were evaluated on 100 plants per treatment over a 27-month period covering the growth of the stool and of the first ratoon. Significant differences between treatments were observed only during the first six months of field growth of sugarcane stools. Stems produced from in vitro cultured material, irrespective of their cryopreservation status, had a smaller diameter and a shorter height than those produced from macropropagated material. These differences disappeared by 12 months of stool field growth.


Assuntos
Criopreservação/métodos , Poaceae/embriologia , Sementes/crescimento & desenvolvimento , Técnicas In Vitro , Fenômenos Fisiológicos Vegetais , Caules de Planta/anatomia & histologia , Fatores de Tempo
13.
Appl Radiat Isot ; 52(2): 289-97, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10697738

RESUMO

PIXE elemental analysis of sediments, speleothems, and other geological formations related to the karst of the Sierra de San Carlos is presented. The similarity of the elemental composition of the sediments studied, as well as the alluvial regime which created them, indicate their common origin at each location. The Sr/Ca concentration ratio of a stalactite indicates that the average atmospheric temperature 12,000 and 18,000 years B.P. was colder than that of 6000 years B.P.


Assuntos
Sedimentos Geológicos/análise , Geologia/métodos , Cálcio/análise , Clima , Cuba , Geografia , Espectrometria por Raios X/métodos , Estrôncio/análise , Tempo
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