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1.
Transfus Med ; 29(6): 454-459, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31680331

RESUMO

OBJECTIVES: To determine whether it was feasible to use a haemorrhage assessment tool (HAT) within a trauma trial and whether the data obtained could differentiate patients who had achieved haemostasis. BACKGROUND: Major haemorrhage is one of the leading causes of death worldwide, affecting 40% of trauma patients. Clinical trials evaluating haemostatic interventions often use transfusion outcomes as a primary endpoint. Transfusion is highly dependent on local practice, limiting its reliability as a robust, transferable endpoint. METHODS: A five-point HAT questionnaire was applied to participants enrolled into the EFIT-1 trial. This RCT evaluated the feasibility of administering a 6 g fibrinogen concentrate to patients with severe trauma haemorrhage. RESULTS: Of participants, 98% completed a HAT; 75% participants had 'achieved haemostasis' at the time of tool completion, as determined by clinical acumen alone. HAT scores were able to differentiate which participants required transfusion after 3 h. Of participants, 56% were transfused red blood cells when they scored 0-2, compared to 17% with HAT scores between 3 and 5. CONCLUSION: This study has confirmed the feasibility of using a HAT during the emergency care of patients suffering trauma haemorrhage, and future studies should be conducted to determine its value as an endpoint in haemostasis studies.


Assuntos
Serviços Médicos de Emergência , Transfusão de Eritrócitos , Hemorragia , Hemostasia , Inquéritos e Questionários , Ferimentos e Lesões , Feminino , Hemorragia/diagnóstico , Hemorragia/terapia , Humanos , Masculino , Projetos Piloto , Ferimentos e Lesões/diagnóstico , Ferimentos e Lesões/terapia
2.
Vox Sang ; 113(3): 251-259, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29318636

RESUMO

BACKGROUND: There continues to be uncertainty about the optimal approach to documenting bleeding data in platelet transfusion trials, with a desire to apply a common assessment tool across all trials. With this in mind, a consensus bleeding assessment tool (BAT) has been developed by the Biomedical Excellence for Safer Transfusion (BEST) collaborative, based on review of data collection forms used in published randomized trials and following content validation with a range of healthcare professionals at seven haematology centres through BEST members. This study aimed to evaluate reliability and reproducibility of the consensus BAT. METHODS: Replicated clinical assessments of bleeding were undertaken by participants with haematological malignancies recruited at four haematology centres in an international, multicentred, observational study. Concordance of repeat assessments was calculated for agreement in site and grade of bleeding observed. RESULTS: Forty patients consented to participate, and 13 trained bleeding assessors collected these data. Bleeding assessments were carried out on 113 separate days. Of all 225 bleeding assessments, 204 were compared for grade concordance, and 160 were compared for site concordance. There was very good grade concordance (83%, 95% confidence interval 74-93%) and good bleeding site concordance (69%, 95% confidence interval 57-79%) in observations of bleeding. Discordance was primarily in relation to assessing skin bleeding. CONCLUSIONS: Alongside a structured training programme, levels of concordance for a consensus BAT were high. Researchers using assessment tools for bleeding need to balance comprehensive data collection against potential loss of accuracy for some types of bleeding, such as skin findings.


Assuntos
Neoplasias Hematológicas/terapia , Hemorragia/patologia , Transfusão de Plaquetas/normas , Adulto , Feminino , Hemorragia/epidemiologia , Hemorragia/etiologia , Humanos , Masculino , Transfusão de Plaquetas/efeitos adversos , Reprodutibilidade dos Testes
3.
Am J Transplant ; 17(2): 411-419, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27428556

RESUMO

The gap between supply and demand in kidney transplantation has led to increased use of marginal kidneys; however, kidneys with acute kidney injury are often declined/discarded. To determine whether this policy is justified, we analyzed outcomes of donor kidneys with acute kidney injury (AKI) in a large UK cohort. A retrospective analysis of the UK Transplant Registry evaluated deceased donors between 2003 and 2013. Donors were classified as no AKI, or AKI stage 1-3 according to Acute Kidney Injury Network (AKIN) criteria. Relationship of AKI with delayed graft function/primary nonfunction (DGF/PNF), estimated glomerular filtration rate (eGFR), and graft-survival at 90 days and 1 year was analyzed. There were 11 219 kidneys (1869 [17%] with AKI) included. Graft failure at 1 year is greater for donors with AKI than for those without (graft survival 89% vs. 91%, p = 0.02; odds ratio (OR) 1.20 [95% confidence interval (CI): 1.03-1.41]). DGF rates increase with donor AKI stage (p < 0.005), and PNF rates are significantly higher for AKIN stage 3 kidneys (9% vs. 4%, p = 0.04) Analysis of association between AKI and recipient eGFR suggests a risk of inferior eGFR with AKI versus no AKI (p < 0.005; OR 1.25 [95% CI: 1.08-1.31]). We report a small reduction in 1-year graft-survival of kidneys from donors with AKI. We conclude that AKI stage 1 or 2 kidneys should be used; however, caution is advised for AKI stage 3 donors.


Assuntos
Injúria Renal Aguda/fisiopatologia , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto , Transplante de Rim , Obtenção de Tecidos e Órgãos/métodos , Adolescente , Adulto , Cadáver , Feminino , Taxa de Filtração Glomerular , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Doadores de Tecidos , Reino Unido/epidemiologia , Adulto Jovem
4.
Transfus Med ; 22(4): 285-93, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22734826

RESUMO

BACKGROUND: Statistical process control (SPC) is used to monitor the performance of blood component collection and production processes in the UK and elsewhere. The sensitivity of the applied technique(s) needs to be matched to the clinical importance of the parameter being monitored such that significant deviations in the process mean and/or variability of critical parameters (e.g. the leucocyte content of leucodepleted components) are detected and investigated immediately. AIMS: This study assessed the sensitivity and specificity of a range of techniques for variable and attribute (proportion non-conforming) data. MATERIALS AND METHODS: Comparison was based on a range of simulated and 'live' blood component quality monitoring data including X/R, cumulative sum (CUSUM) procedures, the scan statistic and np charts. RESULTS: X/R and CUSUM could detect shifts of two standard deviations in the process mean within 5 days. Current leucocyte count data (substantially skewed even after log transformation) was found to be better suited to attribute analysis. CUSUM alone was able to detect shifts on the same day when based on 20 or more samples and achieved acceptable specificity. CONCLUSIONS: CUSUM procedures for proportion non-conforming can usefully augment existing X/R techniques for leucodepletion monitoring, provide valid control limits and the required sensitivity. The scan statistic and 'np' charts offered no obvious advantages.


Assuntos
Transfusão de Componentes Sanguíneos/métodos , Segurança do Sangue , Sistemas Computadorizados de Registros Médicos , Modelos Estatísticos , Controle de Qualidade , Transfusão de Componentes Sanguíneos/instrumentação , Feminino , Humanos , Masculino , Reino Unido
5.
Hum Reprod ; 25(10): 2465-74, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20729236

RESUMO

BACKGROUND: The inadequacies of oocyte in vitro maturation (IVM) systems for both non-human primates and humans are evidenced by reduced fertilization and poor embryonic development, and may be partly explained by significantly lower glutathione (GSH) contents compared with in vivo matured (IVO) oocytes. As this influence has not been fully explored, this study investigated the effect of the GSH donor, glutathione ethyl ester (GSH-OEt), on the IVM and development of macaque oocytes as a model of human oocyte IVM. METHODS: Macaque oocytes derived from unstimulated ovaries were cultured in mCMRL-1066 alone or supplemented with 3 or 5 mM GSH-OEt. In vitro matured oocytes were subjected to the GSH assay, fixed for the assessment of spindle morphology or prepared ICSI. Embryo development of zygotes cultured in mHECM-9 was assessed up to Day 9 post-ICSI. RESULTS Supplementation of the maturation medium with GSH-OEt significantly increased oocyte maturation and normal fertilization rates compared with control oocytes, but only 5 mM GSH-OEt significantly increased the oocyte and cumulus cell GSH content. Confocal microscopy revealed significant differences in the spindle morphology between IVO and control in vitro matured metaphase II oocytes. Oocytes matured with 5 mM GSH-OEt exhibited spindle area and spindle pole width similar to that seen in the IVO oocyte. While no significant differences were observed in blastocyst rates, addition of 3 mM GSH-OEt during IVM significantly increased the proportion of embryos developing to the 5-8 cell stage while 5 mM GSH-OEt significantly increased the proportion of morula-stage embryos compared with controls. CONCLUSIONS: Supplementation of the IVM medium with GSH-OEt promotes better maturation and normal fertilization of macaque oocytes compared with non-supplemented medium. However, further improvement of the primate oocyte IVM culture system is required to support better blastocyst development of oocytes derived from unstimulated ovaries.


Assuntos
Glutationa/análogos & derivados , Oócitos/efeitos dos fármacos , Ovário/efeitos dos fármacos , Animais , Blastocisto/citologia , Blastocisto/fisiologia , Meios de Cultura , Células do Cúmulo/citologia , Células do Cúmulo/efeitos dos fármacos , Feminino , Glutationa/farmacologia , Humanos , Macaca , Oócitos/crescimento & desenvolvimento , Oócitos/ultraestrutura , Ovário/crescimento & desenvolvimento , Ovário/ultraestrutura , Fuso Acromático/ultraestrutura
6.
Reprod Fertil Dev ; 22(6): 1032-40, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20591337

RESUMO

Fertilisation and development of IVM non-human primate oocytes is limited compared with that of in vivo-matured (IVO) oocytes. The present study describes the IVM of macaque oocytes with reference to oocyte glutathione (GSH). Timing of maturation, comparison of IVM media and cysteamine (CYS) supplementation as a modulator of GSH were investigated. A significantly greater proportion of oocytes reached MII after 30 h compared with 24 h of IVM. Following insemination, IVM oocytes had a significantly lower incidence of normal fertilisation (i.e. 2PN = two pronuclei and at least one polar body) and a higher rate of abnormal fertilisation (1PN = one pronucleus and at least one polar body) compared with IVO oocytes. Immunofluorescence of 1PN zygotes identified incomplete sperm head decondensation and failure of male pronucleus formation as the principal cause of abnormal fertilisation in IVM oocytes. The IVO oocytes had significantly higher GSH content than IVM oocytes. Cumulus-denuded oocytes had significantly lower GSH following IVM compared with immature oocytes at collection. Cysteamine supplementation of the IVM medium significantly increased the GSH level of cumulus-intact oocytes and reduced the incidence of 1PN formation, but did not improve GSH levels of the denuded oocyte. Suboptimal GSH levels in macaque IVM oocytes may be related to reduced fertilisation outcomes.


Assuntos
Fertilização/fisiologia , Glutationa/análise , Oócitos/química , Oócitos/crescimento & desenvolvimento , Análise de Variância , Animais , Células Cultivadas , Meios de Cultura , Feminino , Fertilização in vitro , Imunofluorescência , Macaca fascicularis , Macaca nemestrina , Fatores de Tempo
7.
Reprod Fertil Dev ; 22(4): 597-605, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20353719

RESUMO

Glutathione (GSH) is synthesised during oocyte maturation and represents the oocyte's main non-enzymatic defence against oxidative stress. Inadequate defence against oxidative stress may be related to poor embryo quality and viability. In the present study, bovine oocytes were matured in vitro in the presence of GSH ethyl ester (GSH-OEt), a cell permeable GSH donor, and its effects on subsequent fertilisation and embryo development were assessed. GSH-OEt significantly increased the GSH content of IVM oocytes without affecting fertilisation or Day 3 cleavage rates. Maturation in the presence of GSH-OEt did not significantly increase the blastocyst rate compared with control oocytes. However, 5 mM GSH-OEt treatment resulted in significantly higher blastocyst total cell number. The GSH level of IVM oocytes was significantly decreased in the absence of cumulus cells and when cumulus-oocyte complexes were cultured in the presence of buthionine sulfoximine (BSO), an inhibitor of GSH synthesis. The addition of GSH-OEt to cumulus-denuded or BSO-treated oocytes increased the GSH content of bovine oocytes and restored the rate of normal fertilisation, but not embryo development, to levels seen in control oocytes. Thus, GSH-OEt represents a novel approach for effective in vitro elevation of bovine oocyte GSH and improvement in blastocyst cell number.


Assuntos
Bovinos/fisiologia , Fertilização in vitro/veterinária , Glutationa/análogos & derivados , Oócitos/fisiologia , Animais , Antimetabólitos/farmacologia , Butionina Sulfoximina/farmacologia , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/fisiologia , Feminino , Glutationa/metabolismo , Glutationa/farmacologia , Masculino , Microscopia de Fluorescência/veterinária , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Oócitos/ultraestrutura , Gravidez
8.
Reprod Fertil Dev ; 20(5): 579-88, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18577355

RESUMO

Glutathione (GSH) is the main non-enzymatic defence against oxidative stress and is a critical intracellular component required for oocyte maturation. In the present study, several modulators of intracellular GSH were assessed for their effect on the in vitro maturation (IVM) and intracellular GSH content of bovine metaphase (MII) oocytes. Of the five GSH modulators tested, only the cell-permeable GSH donor glutathione ethyl ester (GSH-OEt) significantly increased the GSH content of IVM MII oocytes in a concentration-dependent manner without adversely affecting oocyte maturation rate. The GSH level in IVM MII oocytes was greatly influenced by the presence or absence of cumulus cells and severely restricted when oocytes were cultured in the presence of buthionine sulfoximine (BSO), an inhibitor of GSH synthesis. The addition of GSH-OEt to cumulus-denuded or BSO-treated oocytes increased the GSH content of bovine MII oocytes. Supplementation of the maturation medium with bovine serum albumin (BSA) or fetal calf serum (FCS) affected the GSH content of IVM MII oocytes, with greater levels attained under BSA culture conditions. The addition of GSH-OEt to the maturation medium increased the GSH content of IVM MII oocytes, irrespective of protein source. Spindle morphology, as assessed by immunocytochemistry and confocal microscopy, displayed distinct alterations in response to changes in oocyte GSH levels. GSH depletion caused by BSO treatment tended to widen spindle poles and significantly increased spindle area. Supplementation of the IVM medium with GSH-OEt increased spindle length, but did not significantly alter spindle area or spindle morphology. GSH-OEt represents a novel oocyte-permeable and cumulus cell-independent approach for effective elevation of mammalian oocyte GSH levels.


Assuntos
Glutamato-Cisteína Ligase/metabolismo , Glutationa/metabolismo , Oócitos/crescimento & desenvolvimento , Oogênese/fisiologia , Aminobutiratos/farmacologia , Animais , Bovinos , Células Cultivadas , Simulação por Computador , Meios de Cultura/química , Meios de Cultura/farmacologia , Células do Cúmulo/efeitos dos fármacos , Células do Cúmulo/metabolismo , Células do Cúmulo/fisiologia , Cisteína/análogos & derivados , Cisteína/farmacologia , Feminino , Glutationa/análogos & derivados , Glutationa/farmacologia , Mercaptoetanol/farmacologia , Modelos Biológicos , Oócitos/metabolismo , Fuso Acromático/efeitos dos fármacos , Fuso Acromático/metabolismo
9.
Biol Reprod ; 71(5): 1591-7, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15240425

RESUMO

Implantation and early pregnancy, and the potential effects of the reproductive-hormone relaxin, were examined in the cynomolgus macaque (Macaca fascicularis) following in vitro fertilization and embryo transfer. Mature oocytes were collected from regularly cycling, female cynomolgus monkeys subjected to ovarian superovulation using recombinant human FSH and hCG. Oocytes fertilized in vitro were cultured to the 4- to 8-cell stage, slow-cooled, and stored in liquid nitrogen before thawing and embryo transfer. Regularly cycling recipients were administered recombinant human relaxin or vehicle for 21 days through the peri-implantation period (Day 0 = pump implantation), during which time the thawed embryos were transferred (Day 7). Endometrial thickness and the number of gestational sacs were monitored by ultrasound at three time points (Days 7, 21, and 28). The number of days of placental sign (implantation bleeding) in pregnant females and menses in nonpregnant females were also recorded. Implantation (gestational sacs/embryo transferred) and multiple pregnancy (multiple gestations/ pregnant recipient) rates were slightly higher in relaxin-treated recipients compared to vehicle-treated recipients. Administration of relaxin was associated with increased implantation bleeding in pregnant females. Endometrial thickness was increased in relaxin-treated recipients at Days 7 and 28 compared to Day 0, but these differences were not observed at the same time points in vehicle-treated females. Systemic administration of recombinant human relaxin in an in vitro fertilization/embryo transfer setting was associated with effects consistent with a role for this hormone in endometrial physiology in primates.


Assuntos
Implantação do Embrião/efeitos dos fármacos , Fertilização in vitro , Macaca fascicularis/fisiologia , Prenhez/efeitos dos fármacos , Relaxina/farmacologia , Animais , Transferência Embrionária , Endométrio/diagnóstico por imagem , Endométrio/efeitos dos fármacos , Feminino , Humanos , Masculino , Gravidez , Gravidez Múltipla/estatística & dados numéricos , Proteínas Recombinantes/farmacologia , Relaxina/sangue , Ultrassonografia
10.
Am J Primatol ; 58(4): 169-74, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12478625

RESUMO

Cryostorage of nonhuman primate embryos by time-consuming slow-cooling methods is often limited to early cleavage stages. Effective rapid-cooling methods have been developed for many species and represent valuable tools for laboratory- and field-based studies of nonhuman primate reproductive biology. However, few rapid-cooling protocols have been applied to nonhuman primate embryos in terms of comparing various developmental stages. Here we compare slow cooling vs. two- and three-step rapid cooling of two-, four-, and eight-cell Macaca fascicularis (Mf) embryos. Rapid cooling was conducted in open pulled straws (OPS) using cooling solutions containing reduced quantities of ethylene glycol (EG) and supplemented with either of two high-molecular-weight polymers, ficoll and dextran. The survival of the slow-cooled embryos, but not the rapid-cooled embryos, was independent of embryonic stage at cryostorage. Slow cooling was associated with greater cell survival (82%) post thaw compared to warming following rapid cooling (18-29%). Slow cooling resulted in a high proportion of embryo survival (18/20; 90%) and cleavage (15/18; 83%) post thaw. Rapid cooling resulted in significantly reduced percentages of embryo survival (26-32%) and embryo cleavage in culture (29-38%) after warming. Conventional slow cooling was more effective than the rapid-cooling protocols employed in this study for cryopreservation of early-cleavage-stage Mf embryos.


Assuntos
Fase de Clivagem do Zigoto/fisiologia , Criopreservação/métodos , Desenvolvimento Embrionário e Fetal , Macaca fascicularis/embriologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Fase de Clivagem do Zigoto/citologia , Fase de Clivagem do Zigoto/efeitos dos fármacos , Dextranos/farmacologia , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Fertilização in vitro , Ficoll/farmacologia , Soluções , Taxa de Sobrevida , Temperatura , Fatores de Tempo
11.
Am J Primatol ; 57(4): 203-12, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12210672

RESUMO

In vitro production of blastocyst stage embryos from Macaca fascicularis (Mf) has not previously been demonstrated without cell support. Historical data indicates that a large proportion of Mf embryos arrest at the morula stage in nonsequential culture medium (NSM) lacking serum supplementation and/or cell support. Here we report the application of a sequential culture system supporting in vitro production of Mf blastocysts. Mf embryos produced by in vitro fertilization (IVF; n = 69) were subjected to in vitro culture without cell support in either a commercial sequential embryo culture medium (SM) or an NSM. At 24 hr post-insemination (PI) embryos generated from in vivo and in vitro matured oocytes and cultured in the NSM cleaved to two or more cells in significantly greater proportions (15/23; 65%) compared to embryos cultured in SM (14/46; 30%). However, by day 3 PI embryo development beyond eight cells was not different in NSM (9/23; 39%) compared to SM (25/46; 54%). At day 5 PI embryo development to the morula stage was slightly lower in NSM (8/23, 35%) compared to SM (21/46, 45%), and embryo degeneration was slightly higher in NSM (9/23, 39%) compared to SM (9/46, 20%). After 7-9 days of in vitro culture, embryo development to the blastocyst stage and embryo degeneration were significantly lower and higher, respectively, in NSM (0/23, 0%; and 23/23, 100%) compared to SM (9/46, 20%; and 26/46, 56%). In this study the sequential culture system was better able to support in vitro development of Mf embryos compared to nonsequential culture systems.


Assuntos
Fertilização in vitro/veterinária , Macaca fascicularis/embriologia , Animais , Blastocisto , Meios de Cultura , Desenvolvimento Embrionário e Fetal , Feminino
12.
Mol Reprod Dev ; 56(3): 372-7, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10862004

RESUMO

Tetraploid bovine blastocysts were produced experimentally by electrofusion of in vitro matured and fertilized, zona-enclosed two-cell embryos (33-35 hr after initiation of sperm-egg incubation) using three fusion protocols. Field strengths of 1.0, 1.4, and 2.4 kV/cm were tested and the rate of fusion, subsequent cleavage, and blastocyst development were measured for each. High rates of fusion (76.5% +/- 2.8%), cleavage (72.5% +/- 7.4%) and blastocyst development (56.1% +/- 6.4%) were achieved with the application of 1. 4 kV/cm as a single 100-microseconds pulse. Embryos were scored 30 and 60 min after stimulation for fusion. No time effect for fusion, cleavage, or blastocyst development was observed. Chromosome preparations of day 7 blastocysts revealed 12.5% of fused embryos were tetraploid. This is a significant increase from that found in nonfused embryos where spontaneous tetraploidy did not occur. An electrical stimulus of 1.0 kV/cm applied as two 50-microseconds pulses produced significantly less one-cell embryos (64.2% +/- 3.0%) compared to 1.4 kV/cm while cleavage (79.9% +/- 3.4) and blastocyst development (44.6% +/- 4.0%) were not different from that for unexposed control embryos (89.5% +/- 2.3% and 57.2% +/- 3.2%, respectively). Embryos fused at 2.4 kV/cm applied as a single 30-microseconds pulse (69.7% +/- 5.7%) showed significantly lower cleavage (72.1% +/- 3.7%) and blastocyst rates (40.2% +/- 4.6%) compared to the unexposed control.


Assuntos
Blastocisto/fisiologia , Zigoto/fisiologia , Animais , Bovinos , Fusão Celular , Cariotipagem , Fatores de Tempo
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