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Only 30% of embryos from in vitro fertilized oocytes successfully implant and develop to term, leading to repeated transfer cycles. To reduce time-to-pregnancy and stress for patients, there is a need for a diagnostic tool to better select embryos and oocytes based on their physiology. The current standard employs brightfield imaging, which provides limited physiological information. Here, we introduce METAPHOR: Metabolic Evaluation through Phasor-based Hyperspectral Imaging and Organelle Recognition. This non-invasive, label-free imaging method combines two-photon illumination and AI to deliver the metabolic profile of embryos and oocytes based on intrinsic autofluorescence signals. We used it to classify i) mouse blastocysts cultured under standard conditions or with depletion of selected metabolites (glucose, pyruvate, lactate); and ii) oocytes from young and old mouse females, or in vitro-aged oocytes. The imaging process was safe for blastocysts and oocytes. The METAPHOR classification of control vs. metabolites-depleted embryos reached an area under the ROC curve (AUC) of 93.7%, compared to 51% achieved for human grading using brightfield imaging. The binary classification of young vs. old/in vitro-aged oocytes and their blastulation prediction using METAPHOR reached an AUC of 96.2% and 82.2%, respectively. Finally, organelle recognition and segmentation based on the flavin adenine dinucleotide signal revealed that quantification of mitochondria size and distribution can be used as a biomarker to classify oocytes and embryos. The performance and safety of the method highlight the accuracy of noninvasive metabolic imaging as a complementary approach to evaluate oocytes and embryos based on their physiology.
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Blastocisto , Oocitos , Animales , Blastocisto/metabolismo , Ratones , Oocitos/metabolismo , Femenino , Orgánulos/metabolismo , Imagen Óptica/métodosRESUMEN
RESEARCH QUESTION: To what extent does the type and concentration of protein and the type of culture medium affect the sensitivity of the mouse embryo assay (MEA) to detect Triton X-100 (TX-100) in culture media? DESIGN: The effect of the concentration of bovine serum albumin (BSA) and human serum albumin (HSA) was assessed by supplementing media with 0.5 or 5 mg/ml. Potassium-supplemented simplex optimized medium (KSOM) and human tubal fluid (HTF) were used as complex and simple formulation media, respectively. Variables were combined, forming study groups where embryos were cultured in test media spiked with a sublethal TX-100 concentration. The conditions of greatest sensitivity were determined by statistical comparison of blastocyst formation rates and total cell counts between groups. RESULTS: Although all of the study groups showed equal capacity for sustaining proper embryo development, the reported sensitivity of the MEA differed between groups when subjected to TX-100. HTF conferred significantly greater sensitivity than KSOM regardless of the type and concentration of protein used, and medium supplementation with 5 mg/ml BSA rather than 0.5 mg/ml BSA resulted in significantly higher sensitivity regardless of the type of medium used. This increase in concentration also resulted in higher sensitivity when supplementing HTF with HSA. The BSA groups provided more sensitivity than their HSA counterparts, except for the KSOMâ¯+â¯0.5 mg/ml BSA group. Cell count analysis did not provide further significant conclusions. CONCLUSIONS: For TX-100 detection within culture medium, the type and concentration of protein and the type of culture medium have a direct effect on MEA sensitivity. These results could help to standardize the MEA protocol, and increase its ability to detect sublethal concentrations of embryotoxic substances, especially TX-100, thus avoiding possible clinical harmful effects.
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RESEARCH QUESTION: Can an automated sperm injection robot perform Automated Intracytoplasmic Sperm Injection (ICSIA) for use in human IVF? DESIGN: The ICSIA robot automated the sperm injection procedure, including injection pipette advancement, zona pellucida and oolemma penetration with piezo pulses, and pipette removal after sperm release. The robot was first tested in mouse, hamster and rabbit oocytes, and subsequently using discarded human oocytes injected with microbeads. A small clinical pilot trial was conducted with donor oocytes to study the feasibility of the robot in a clinical setting. The ICSIA robot was controlled by engineers with no micromanipulation experience. Results were compared with those obtained with manual ICSI conducted by experienced embryologists. RESULTS: The ICSIA robot demonstrated similar results to the manual procedure in the different animal models tested as well as in the pre-clinical validations conducted in discarded human oocytes. In the clinical validation, 13 out of 14 oocytes injected with ICSIA fertilized correctly versus 16 out of 18 in the manual control; eight developed into good-quality blastocysts versus 12 in the manual control; and four were diagnosed as chromosomally normal versus 10 euploid in the manual control. Three euploid blastocysts from the ICSIA robot group have been transferred into two recipients, which resulted in two singleton pregnancies and two babies born. CONCLUSIONS: The ICSIA robot showed high proficiency in injecting animal and human oocytes when operated by inexperienced personnel. The preliminary results obtained in this first clinical pilot trial are within key performance indicators.
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Fertilización In Vitro , Inyecciones de Esperma Intracitoplasmáticas , Femenino , Humanos , Masculino , Embarazo , Fertilización , Fertilización In Vitro/métodos , Oocitos , Semen , Inyecciones de Esperma Intracitoplasmáticas/métodos , EspermatozoidesRESUMEN
BACKGROUND: Frailty and sarcopenia have been extensively studied in heart failure (HF) patients, but their coexistence is unknown. The aim of this work is to describe the coexistence of these conditions in a sample of HF outpatients and its association with the use of medication and left-ventricular ejection fraction. METHODS: Participants in this cross-sectional study were recruited from a HF outpatients' clinic in northern Portugal. Frailty phenotype was assessed according to Fried et al. Sarcopenia was evaluated according to the revised consensus of the European Working Group on Sarcopenia in Older People. RESULTS: A total of 136 HF outpatients (33.8% women, median age 59 years) integrated this study. Frailty and sarcopenia accounted for 15.4% and 18.4% of the sample, respectively. Coexistence of frailty and sarcopenia was found in 8.1% of the participants, while 17.6% had only one of the conditions. In multivariable analysis (n = 132), increasing age (OR = 1.13;95%CI = 1.06,1.20), being a woman (OR = 65.65;95%CI = 13.50, 319.15), having heart failure with preserved ejection fraction (HFpEF) (OR = 5.61; 95%CI = 1.22, 25.76), and using antidepressants (OR = 11.05; 95%CI = 2.50, 48.82), anticoagulants (OR = 6.11; 95%CI = 1.69, 22.07), furosemide (OR = 3.95; 95%CI = 1.07, 14.55), and acetylsalicylic acid (OR = 5.01; 95%CI = 1.10, 22.90) were associated with increased likelihood of having coexistence of frailty and sarcopenia, while using statins showed the inverse effect (OR = 0.06; 95%CI = 0.01, 0.30). CONCLUSIONS: The relatively low frequency of coexistence of frailty and sarcopenia signifies that each of these two conditions still deserve individual attention from health professionals in their clinical practice and should be screened separately. Being a woman, older age, having HFpEF, using anticoagulants, antidepressants, loop diuretics and acetylsalicylic acid, and not using statins, were associated with having concomitant frailty and sarcopenia. These patients can potentially benefit from interventions that impact their quality of life such as nutritional and mental health interventions and exercise training.
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Fragilidad , Insuficiencia Cardíaca , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Sarcopenia , Humanos , Femenino , Anciano , Persona de Mediana Edad , Masculino , Sarcopenia/diagnóstico , Sarcopenia/epidemiología , Sarcopenia/complicaciones , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/epidemiología , Volumen Sistólico , Fragilidad/diagnóstico , Fragilidad/epidemiología , Estudios Transversales , Función Ventricular Izquierda , Calidad de Vida , Pacientes Ambulatorios , Anticoagulantes , Antidepresivos , AspirinaRESUMEN
BACKGROUND: Sarcopenia is prevalent in heart failure (HF) patients, contributing to its poor prognosis. Statin use is postulated as a probable risk for developing sarcopenia, but little is known regarding this association in HF patients. This work aims at classifying and characterising sarcopenia and at describing the association of statin use with sarcopenia in a sample of Portuguese HF outpatients. METHODS: In this cross-sectional study, a sample of 136 HF patients (median age: 59 years, 33.8% women) was recruited from an HF outpatients' clinic of a University Hospital in Portugal. Sarcopenia was defined according to the European Working Group on Sarcopenia in Older People 2. Clinical, nutritional, and dietary data were collected. RESULTS: A total of 25 (18.4%) individuals were categorised as sarcopenic, ranging from 12.2% in younger (< 65 years) participants vs. 30.4% in older ones and from 3.3% in men vs. 47.8% in women. Severe sarcopenia accounted for 7.4% of the sample and sarcopenic obesity was identified in 5.1% of the individuals. A total of 65.4% of the participants were statin users. In multivariable analysis (n = 132, 25 sarcopenic), the use of statins was inversely associated with sarcopenia (OR = 0.03; 95% CI = 0.01, 0.30). Each additional age year was associated with a 9% increase in the likelihood of being sarcopenic (OR = 1.09; 95% CI = 1.01, 1.17), and each Kg.m-2 increment in body mass index was associated with a 21% decrease in the likelihood of sarcopenia (OR = 0.79; 95% CI = 0.65, 0.96). The daily use of five or more medicines was also directly associated with sarcopenia (OR = 26.87; 95% CI = 2.01, 359.26). On the other hand, being a man and being physically active were inversely associated with sarcopenia (OR = 0.01; 95% CI = 0.00, 0.07 and OR = 0.09; 95% CI = 0.01, 0.65, respectively). CONCLUSIONS: Contrary to what was expected, patients medicated with statins were less likely to be sarcopenic. Although this finding deserves further research, we hypothesise that this might be related to the pleiotropic effects of statins on endothelial function, contributing to better neuromuscular fitness.
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Insuficiencia Cardíaca , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Sarcopenia , Anciano , Estudios Transversales , Femenino , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/epidemiología , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Masculino , Persona de Mediana Edad , Pacientes Ambulatorios , Sarcopenia/complicaciones , Sarcopenia/diagnóstico , Sarcopenia/epidemiologíaRESUMEN
OBJECTIVE: Since its development, cumulative evidence has accumulated regarding the prognostic value of the Malnutrition-Inflammation Score (MIS/Kalantar score) prognostic value; however, there is a shortage of recent and large studies with comprehensive statistical methodologies that contribute to support a higher level of evidence and a consensual cutoff. The aim of this study was to assess the strength of MIS association with hospitalization and mortality in a nationwide cohort. METHODS: This was a historical cohort study of hemodialysis patients from 25 outpatient centers followed up for 48 months. Univariable and multivariable Cox additive regression models were used to analyze the data. The C-index was estimated to assess the performance of the final model. RESULTS: Two thousand four hundred forty-four patients were analyzed, 59.0% males, 32.0% diabetic, and median age of 71 years (P25 = 60, P75 = 79). During a median period of 45-month follow-up, with a maximum of 48 months (P25 = 31; P75 = 48), 875 patients presented an MIS <5 (35.8%) and 860 patients (35.2%) died. The proportion of deaths was 23.1% for patients with the MIS <5 and 41.9% if the MIS ≥5 (P < .001). A total of 1,528 patients (62.5%) were hospitalized with a median time to the first hospitalization of 26 months (P25 = 9; P75 = 45). A new cutoff point regarding the risk of death, MIS ≥6, was identified for this study data set. In multivariable analysis for hospitalization risk, a higher MIS, higher comorbidity index, and arteriovenous graft or catheter increased the risk, whereas higher Kt/V and higher albumin had a protective effect. In multivariable analysis for mortality risk, adjusting for age, albumin, normalized protein catabolic rate, Charlson comorbidity index, interdialytic weight gain, Kt/V, diabetes, hematocrit, and vascular access, patients with the MIS ≥6 showed a hazard ratio of 1.469 (95% confidence interval: 1.262-1.711; P < .001). Higher age, higher interdialytic weight gain, higher comorbidity index, and catheter increased significantly the risk, whereas higher Kt/V, higher albumin, and higher normalized protein catabolic rate (≥1.05 g/kg/d) reduced the risk. CONCLUSION: The MIS maintains its relevant and significant association with hospitalization and mortality.
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Desnutrición , Anciano , Albúminas , Estudios de Cohortes , Comorbilidad , Femenino , Hospitalización , Humanos , Inflamación/complicaciones , Masculino , Desnutrición/complicaciones , Desnutrición/diagnóstico , Persona de Mediana Edad , Estado Nutricional , Pronóstico , Diálisis Renal , Factores de Riesgo , Aumento de PesoRESUMEN
BACKGROUND AND AIM: Frailty phenotype (FP) is very common in heart failure (HF) and both syndromes worsen one another. The aim of this study is to first describe FP in a sample of Portuguese patients with HF, and to analyse its association with nutritional and clinical statuses, namely, muscle mass, obesity and functional class. METHODS AND RESULTS: In this cross-sectional study, a sample of 136 outpatients with HF (24-81 years, 33.8% women) were randomly selected from the appointments' listings of a HF and Transplant clinic in a Portuguese University Hospital. FP was assessed according to Fried et al. muscle mass was estimated from the mid-upper arm muscle circumference; weight status was assessed using the body mass index; HF functional classes were registered. The association between participants' characteristics and FP categories was analysed using logistic ordinal regression. The frequency of pre-frailty and frailty is 57.4% and 15.4%, respectively. Within frail individuals, 52.4% were under the age of 65. In multivariable analysis, frailty was positively associated with age 70 or older (OR = 3.44) and obesity (OR = 2.66), and negatively associated with muscle mass (OR = 0.77) and HF functional classes I (OR = 0.14) or II (OR = 0.29). CONCLUSION: Muscle mass seems to be an important predictor of frailty in patients with HF and should be taken into account when designing intervention plans that allow for reverting or modifying frailty and pre-frailty. Younger patients should be monitored for the presence and evolution of FP.
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Anciano Frágil , Fragilidad/epidemiología , Insuficiencia Cardíaca/epidemiología , Estado Nutricional , Pacientes Ambulatorios , Factores de Edad , Anciano , Antropometría , Composición Corporal , Estudios Transversales , Femenino , Fragilidad/diagnóstico , Fragilidad/fisiopatología , Evaluación Geriátrica , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Fuerza Muscular , Músculo Esquelético/fisiopatología , Evaluación Nutricional , Obesidad/complicaciones , Obesidad/fisiopatología , Portugal/epidemiología , Prevalencia , Pronóstico , Medición de Riesgo , Factores de RiesgoRESUMEN
BACKGROUND: Sodium intake is expected to affect water needs, although compensation mechanisms may not work efficiently particularly in older adults. The aim of this cross-sectional study was to quantify the association between sodium excretion and hydration status in a representative sample of Portuguese older adults. METHODS: A cluster sampling approach was used, representing Portuguese older adults (≥65 years) according to sex, education level and region. From a sample size of 1500 participants, 1318 were eligible for the present analysis. A 24-h urine sample was collected, and volume, osmolality, creatinine and sodium were quantified. Free water reserve (FWR) was used to assess hydration status. Excessive sodium intake was defined as above 2000 mg day-1 as recommended by the World Health Organization. A multivariable binary logistic regression model was used to estimate the association between FWR and sodium excretion. Odds ratios (OR) and respective 95% confidence intervals (95% CI) were calculated. RESULTS: Excessive sodium excretion was observed in 80.0% of women and 91.5% of men, whereas hypohydration affected 10.9% of women and 23.6% of men. After adjusting for confounders, excessive sodium excretion was associated with an increased risk of hypohydration among men (OR = 2.75; 95% CI = 1.06-7.15). CONCLUSIONS: These results stress the positive association between excessive sodium intake and hypohydration in men and highlight the need for implementing strategies regarding the reduction of salt consumption and the promotion of water intake.
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Ingestión de Líquidos , Sodio en la Dieta , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Estado Nutricional , Oportunidad Relativa , Cloruro de Sodio Dietético , Sodio en la Dieta/efectos adversosRESUMEN
BACKGROUND: Assessing body weight in older adults may be challenging. Hence, the present study aimed to develop and cross-validate updated and reproducible equations to estimate body weight in a large sample of older adults, namely among the older-old. METHODS: In total, 1456 individuals aged ≥ 65 years, from the Nutrition UP 65 study, were included in the present analysis. The participants were randomly assigned to one of two sub-samples: development (n = 991) and validation samples (n = 465). Prediction equations using height, mid-upper arm circumference (MUAC), waist circumference (WC), calf circumference (CC) and triceps skinfold thickness (TST) were generated for the development sample using multiple regression analysis and then validated using the validation sample. RESULTS: The model with five predictor variables generated the following equations: females 65-79 years: -114.682 + 0.522 × height (cm) + 0.620 × MUAC (cm) + 0.517 × WC (cm) + 0.893 × CC (cm) + 0.111 × TST (mm) (adjusted r2 = 0.883, standard error of the estimate (SEE) = 4.4); females ≥ 80 years: -110.806 + 0.494 × height (cm) + 0.637 × MUAC (cm) + 0.500 × WC (cm) + 0.986 × CC (cm) + 0.021 × TST (mm) (adjusted r2 = 0.890, SEE = 3.9); males 65-79 years: -114.875 + 0.558 × height (cm) + 0.073 × MUAC (cm) + 0.671 × WC (cm) + 0.717 × CC (cm) + 0.182 × TST(mm) (adjusted r2 = 0.820, SEE=5.0); and males ≥ 80 years: -128.789 + 0.546 × height (cm) + 0.202 × MUAC (cm) + 0.612 × WC (cm) + 1.236 × CC (cm) + 0.093 × TST (mm) (adjusted r2 = 0.906, SEE = 3.5). CONCLUSIONS: Body weight can be estimated with good accuracy in older adults using these sex- and age-specific equations generated from regression models using three to five anthropometric predictor variables.
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Estatura , Estado Nutricional , Anciano , Antropometría , Brazo/anatomía & histología , Índice de Masa Corporal , Peso Corporal , Femenino , Humanos , Masculino , Circunferencia de la CinturaRESUMEN
For many years, the main nitrogen source for patients with phenylketonuria (PKU) was phenylalanine-free amino acid supplements. Recently, casein glycomacropeptide (GMP) supplements have been prescribed due to its functional and sensorial properties. Nevertheless, many doubts still persist about the metabolic effects of GMP compared to free amino acids (fAA) and intact proteins such as casein (CAS). We endeavour to compare, in rats, the metabolic effects of different nitrogen sources. Twenty-four male Wistar rats were fed equal energy density diets plus CAS (control, n = 8), fAA (n = 8) or GMP (n = 8) for 8 weeks. Food, liquid intake and body weight were measured weekly. Blood biochemical parameters and markers of glycidic metabolism were assessed. Glucagon-like peptide-1 (GLP-1) was analysed by ELISA and immunohistochemistry. Food intake was higher in rats fed CAS compared to fAA or GMP throughout the treatment period. Fluid intake was similar between rats fed fAA and GMP. Body weight was systematically lower in rats fed fAA and GMP compared to those fed CAS, and still, from week 4 onwards, there were differences between fAA and GMP. None of the treatments appeared to induce consistent changes in glycaemia, while insulin levels were significantly higher in GMP. Likewise, the production of GLP-1 was higher in rats fed GMP when compared to fAA. Decreased urea, total protein and triglycerides were seen both in fAA and GMP related to CAS. GMP also reduced albumin and triglycerides in comparison to CAS and fAA, respectively. The chronic consumption of the diets triggers different metabolic responses which may provide clues to further study potential underlying mechanisms.
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Caseínas/metabolismo , Dietoterapia , Suplementos Dietéticos , Fragmentos de Péptidos/metabolismo , Animales , Biomarcadores , Peso Corporal , Caseínas/administración & dosificación , Ingestión de Alimentos , Glucosa/metabolismo , Humanos , Inmunohistoquímica , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Fragmentos de Péptidos/administración & dosificación , RatasRESUMEN
Objective: Older adults present higher risk of functional disability detected by handgrip strength and an increased risk of poor health conditions, such as dehydration and low values of the sodium-to-potassium (Na/K) ratio. This study aimed to quantify the association of hydration status and Na/K ratio with handgrip strength, based on the urinary excretion of older adults.Methods: A cross-sectional study was conducted in 735 older adults ≥ 65 years old. Handgrip strength was measured with a Jamar Dynamometer and low values were defined according to body mass index and to sex-specific cutoff points. The hydration status was evaluated based on free water reserve. Sodium and potassium intake were evaluated after converting 24-hour urinary sodium and potassium excretion, respectively. A logistic regression model was used to estimate the probability of presenting low handgrip strength, according to risk of hypohydration and to quartiles of Na/K, stratified by sex and adjusted for potential confounders.Results: The adjusted odds ratio (OR) for presenting low handgrip strength was higher in women at risk of hypohydration, but this association was not found in men. Both women and men with the highest values of Na/K ratio presented higher adjusted OR for low handgrip strength (OR in women was 2.03; 95% confidence interval [CI]: 1.12-3.68, and in men was 2.19; 95% CI: 1.11-4.29).Conclusions: The risk of hypohydration was directly associated with low handgrip strength in older women. In older adults, higher values of urinary Na/K ratio were also directly associated with low handgrip strength.
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Fuerza de la Mano , Estado de Hidratación del Organismo , Potasio/orina , Sodio/orina , Anciano , Anciano de 80 o más Años , Estudios Transversales , Deshidratación/epidemiología , Femenino , Humanos , Masculino , Oportunidad Relativa , Factores SexualesRESUMEN
Amino acid mixtures (AAM) are protein substitutes used for phenylketonuria treatment, but their metabolic effects have not been well characterized. The objective of this study was to compare the acute glycemic response to free amino acids (free AA) from AAM with the response to intact protein (iProtein). Male Wistar rats (n = 14) were administered by gavage a bolus of free AA (n = 7) or iProtein as albumin (n = 7) containing equivalent amounts of nitrogen. Blood glucose and insulin levels were measured at baseline and 15, 30, 60 and 120 minutes later, when gut GLP-1 content and pancreatic insulin, GLP-1 receptor and Ki67 expression were quantified at 120 minutes time point. After AAM, glucose area under the curve (free AA vs iProtein; P < 0.01), serum insulin levels at 120 minutes (free AA vs iProtein; P < 0.05), colon GLP-1 content (free AA vs iProtein; P < 0.01), pancreatic GLP-1 receptor (free AA vs iProtein; P < 0.01) and insulin expression (free AA vs iProtein; p < 0.01) were significantly lower as compared with iProtein. AAM increased Ki67 expression in pancreatic islets (free AA vs iProtein; P < 0.05). In conclusion, this study demonstrated that acute response to AAM differs from iProtein and is characterized by a lower glucose excursion, along with a decrease in gut GLP-1 and pancreatic GLP-1 receptor and insulin. This data suggests the modulation of glycemia by free AA is mediated by the incretin axis.
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Albúminas/administración & dosificación , Aminoácidos/administración & dosificación , Glucemia/metabolismo , Insulina/sangre , Páncreas/metabolismo , Animales , Colon/efectos de los fármacos , Colon/metabolismo , Péptido 1 Similar al Glucagón/metabolismo , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Incretinas/metabolismo , Insulina/análisis , Antígeno Ki-67/metabolismo , Masculino , Páncreas/efectos de los fármacos , Ratas Wistar , Factores de TiempoRESUMEN
RESEARCH QUESTION: Can culture conditions influence the sensitivity of a Mouse Embryo Assay and its potential to detect peroxide-related toxicity in mineral oil samples? DESIGN: Protein type and concentration, embryo density and culture dish design were selected as the variables in the culture system with the potential to influence the assay's sensitivity. Fresh 1-cell mouse embryos were cultured under mineral oil samples with known peroxide concentrations. Protein type (human serum albumin [HSA]â¯+â¯α/ß-Globulins versus HSA versus bovine serum albumin [BSA]), concentration (5 mg/ml versus 0.5 mg/ml), embryo density (25 versus 3 µl/embryo) and culture dish (Petri versus micro-well dish) were adjusted to define the culture conditions with the highest sensitivity. RESULTS: High concentrations of peroxides can be easily detected by current quality control standards. However, for oil samples with a lower concentration of peroxides, supplementing the culture medium with 5 mg/ml of HSAâ¯+â¯alpha/beta-globulins or with HSA resulted in an increased detection of embryo toxicity compared with when BSA was used as the protein supplement. The sensitivity of the assay was greatly reduced when embryos were cultured in groups and when certain micro-well dishes were used. CONCLUSIONS: Current quality control protocols may not be sensitive enough to identify low concentrations of peroxides, which, if undetected, can increase over time and become potentially harmful during gamete and embryo culture. The different parameters established in this study allow the sensitivity of the Mouse Embryo Assays to be optimized to specifically detect peroxides in mineral oil samples prior to their release into the market and their broad use in human IVF.
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Bioensayo , Técnicas de Cultivo de Embriones/métodos , Embrión de Mamíferos/citología , Ratones/embriología , Aceite Mineral/química , Peróxidos/aislamiento & purificación , Animales , Bioensayo/métodos , Bioensayo/normas , Células Cultivadas , Medios de Cultivo/química , Medios de Cultivo/farmacología , Contaminación de Medicamentos , Técnicas de Cultivo de Embriones/normas , Desarrollo Embrionario/efectos de los fármacos , Femenino , Fertilización In Vitro/métodos , Fertilización In Vitro/normas , Masculino , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Aceite Mineral/farmacología , Peróxidos/toxicidad , Proteínas/fisiología , Control de Calidad , Pruebas de Toxicidad/métodos , Pruebas de Toxicidad/normasRESUMEN
Pyrococcus furiosus is a remarkable archaeon able to grow at temperatures around 100 °C. To gain insight into how this model hyperthermophile copes with heat stress, we compared transcriptomic and metabolomic data of cells subjected to a temperature shift from 90 °C to 97 °C. In this study, we used RNA-sequencing to characterize the global variation in gene expression levels, while nuclear magnetic resonance (NMR) and targeted ion exchange liquid chromatography-mass spectrometry (LC-MS) were used to determine changes in metabolite levels. Of the 552 differentially expressed genes in response to heat shock conditions, 257 were upregulated and 295 were downregulated. In particular, there was a significant downregulation of genes for synthesis and transport of amino acids. At the metabolite level, 37 compounds were quantified. The level of di-myo-inositol phosphate, a canonical heat stress solute among marine hyperthermophiles, increased considerably (5.4-fold) at elevated temperature. Also, the levels of mannosylglycerate, UDP-N-acetylglucosamine (UDPGlcNac) and UDP-N-acetylgalactosamine were enhanced. The increase in the pool of UDPGlcNac was concurrent with an increase in the transcript levels of the respective biosynthetic genes. This work provides the first metabolomic analysis of the heat shock response of a hyperthermophile.
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Respuesta al Choque Térmico , Metaboloma , Pyrococcus furiosus/genética , Transcriptoma , Pyrococcus furiosus/metabolismo , TermotoleranciaRESUMEN
BACKGROUND: The halophilic bacterium Chromohalobacter salexigens metabolizes glucose exclusively through the Entner-Doudoroff (ED) pathway, an adaptation which results in inefficient growth, with significant carbon overflow, especially at low salinity. Preliminary analysis of C. salexigens genome suggests that fructose metabolism could proceed through the Entner-Doudoroff and Embden-Meyerhof-Parnas (EMP) pathways. In order to thrive at high salinity, this bacterium relies on the biosynthesis and accumulation of ectoines as major compatible solutes. This metabolic pathway imposes a high metabolic burden due to the consumption of a relevant proportion of cellular resources, including both energy molecules (NADPH and ATP) and carbon building blocks. Therefore, the existence of more than one glycolytic pathway with different stoichiometries may be an advantage for C. salexigens. The aim of this work is to experimentally characterize the metabolism of fructose in C. salexigens. RESULTS: Fructose metabolism was analyzed using in silico genome analysis, RT-PCR, isotopic labeling, and genetic approaches. During growth on fructose as the sole carbon source, carbon overflow was not observed in a wide range of salt concentrations, and higher biomass yields were reached. We unveiled the initial steps of the two pathways for fructose incorporation and their links to central metabolism. While glucose is metabolized exclusively through the Entner-Doudoroff (ED) pathway, fructose is also partially metabolized by the Embden-Meyerhof-Parnas (EMP) route. Tracking isotopic label from [1-13C] fructose to ectoines revealed that 81% and 19% of the fructose were metabolized through ED and EMP-like routes, respectively. Activities of enzymes from both routes were demonstrated in vitro by 31P-NMR. Genes encoding predicted fructokinase and 1-phosphofructokinase were cloned and the activities of their protein products were confirmed. Importantly, the protein encoded by csal1534 gene functions as fructose bisphosphatase, although it had been annotated previously as pyrophosphate-dependent phosphofructokinase. The gluconeogenic rather than glycolytic role of this enzyme in vivo is in agreement with the lack of 6-phosphofructokinase activity previously described. CONCLUSIONS: Overall, this study shows that C. salexigens possesses a greater metabolic flexibility for fructose catabolism, the ED and EMP pathways contributing to a fine balancing of energy and biosynthetic demands and, subsequently, to a more efficient metabolism.
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Chromohalobacter/genética , Chromohalobacter/metabolismo , Fructosa/metabolismo , Glucólisis , Metabolismo de los Hidratos de Carbono/genética , Carbono/metabolismo , Genoma Bacteriano , Glucosa/metabolismo , Redes y Vías Metabólicas , SalinidadRESUMEN
BACKGROUND: Mannosylglycerate (MG) is one of the most widespread compatible solutes among marine microorganisms adapted to hot environments. This ionic solute holds excellent ability to protect proteins against thermal denaturation, hence a large number of biotechnological and clinical applications have been put forward. However, the current prohibitive production costs impose severe constraints towards large-scale applications. All known microbial producers synthesize MG from GDP-mannose and 3-phosphoglycerate via a two-step pathway in which mannosyl-3-phosphoglycerate is the intermediate metabolite. In an early work, this pathway was expressed in Saccharomyces cerevisiae with the goal to confirm gene function (Empadinhas et al. in J Bacteriol 186:4075-4084, 2004), but the level of MG accumulation was low. Therefore, in view of the potential biotechnological value of this compound, we decided to invest further effort to convert S. cerevisiae into an efficient cell factory for MG production. RESULTS: To drive MG production, the pathway for the synthesis of GDP-mannose, one of the MG biosynthetic precursors, was overexpressed in S. cerevisiae along with the MG biosynthetic pathway. MG production was evaluated under different cultivation modes, i.e., flask bottle, batch, and continuous mode with different dilution rates. The genes encoding mannose-6-phosphate isomerase (PMI40) and GDP-mannose pyrophosphorylase (PSA1) were introduced into strain MG01, hosting a plasmid encoding the MG biosynthetic machinery. The resulting engineered strain (MG02) showed around a twofold increase in the activity of PMI40 and PSA1 in comparison to the wild-type. In batch mode, strain MG02 accumulated 15.86 mgMG g DCW -1 , representing a 2.2-fold increase relative to the reference strain (MG01). In continuous culture, at a dilution rate of 0.15 h-1, there was a 1.5-fold improvement in productivity. CONCLUSION: In the present study, the yield and productivity of MG were increased by overexpression of the GDP-mannose pathway and optimization of the mode of cultivation. A maximum of 15.86 mgMG g DCW -1 was achieved in batch cultivation and maximal productivity of 1.79 mgMG g DCW -1 h-1 in continuous mode. Additionally, a positive correlation between MG productivity and growth rate/dilution rate was established, although this correlation is not observed for MG yield.
Asunto(s)
Biotecnología/métodos , Manosa/análogos & derivados , Ingeniería Metabólica/métodos , Saccharomyces cerevisiae/metabolismo , Técnicas de Cultivo Celular por Lotes , Biomasa , Reactores Biológicos/microbiología , Regulación Fúngica de la Expresión Génica , Ácidos Glicéricos/química , Manosa/biosíntesis , Manosa/química , Saccharomyces cerevisiae/enzimología , Saccharomyces cerevisiae/genéticaRESUMEN
Vitrification is currently a well-established technique for the cryopreservation of oocytes and embryos. It can be achieved either by direct (open systems) or indirect (closed systems) contact with liquid nitrogen. While there is not a direct evidence of disease transmission by transferred cryopreserved embryos, it was experimentally demonstrated that cross-contamination between liquid nitrogen and embryos may occur, and thus, the use of closed devices has been recommended to avoid the risk of contamination. Unfortunately, closed systems may result in lower cooling rates compared to open systems, due to the thermal insulation of the samples, which may cause ice crystal formation resulting in impaired results. In our study, we aimed to validate a newly developed vitrification device (Cryotop SC) that has been specifically designed for being used as a closed system. The cooling and warming rates calculated for the closed system were 5.254⯰C/min and 43.522⯰C/min, respectively. Results obtained with the closed system were equivalent to those with the classic Cryotop (open system), with survival rates in oocytes close to 100%. Similarly, the potential of the survived oocytes to develop up to good quality blastocysts after parthenogenetic activation between both groups was statistically equivalent. Assessment of the meiotic spindle and chromosome distribution by fluorescence microscopy in vitrified oocytes showed alike morphologies between the open and closed system. No differences were found either between the both systems in terms of survival rates of one-cell stage embryos or blastocysts, as well as, in the potential of the vitrified/warmed blastocysts to develop to full-term after transferred to surrogate females.
Asunto(s)
Criopreservación/instrumentación , Oocitos , Vitrificación , Animales , Blastocisto/fisiología , Criopreservación/métodos , Femenino , RatonesRESUMEN
Glycerophosphoinositol (GPI) is a compatible solute present in a few hyperthermophiles. Interestingly, different GPI stereoisomers accumulate in Bacteria and Archaea, and the basis for this domain-dependent specificity was investigated herein. The archaeon Archaeoglobus fulgidus and the bacterium Aquifex aeolicus were used as model organisms. The synthesis of GPI involves glycerol phosphate cytidylyltransferase (GCT), which catalyzes the production of CDP-glycerol from CTP and glycerol phosphate, and di-myo-inositol phosphate-phosphate synthase (DIPPS), catalyzing the formation of phosphorylated GPI from CDP-glycerol and l-myo-inositol 1-phosphate. DIPPS of A. fulgidus recognized the two CDP-glycerol stereoisomers similarly. This feature and the ability of 31P nuclear magnetic resonance (NMR) to distinguish the GPI diastereomers provided a means to study the stereospecificity of GCTs. The AF1418 gene and genes aq_185 and aq_1368 are annotated as putative GCT genes in the genomes of A. fulgidus and Aq. aeolicus, respectively. The functions of these genes were determined by assaying the activity of the respective recombinant proteins: AQ1368 and AQ185 are GCTs, while AF1418 has flavin adenine dinucleotide (FAD) synthetase activity. AQ185 is absolutely specific for sn-glycerol 3-phosphate, while AQ1368 recognizes the two enantiomers but has a 2:1 preference for sn-glycerol 3-phosphate. In contrast, the partially purified A. fulgidus GCT uses sn-glycerol 1-phosphate preferentially (4:1). Significantly, the predominant GPI stereoforms found in the bacterium and the archaeon reflect the distinct stereospecificities of the respective GCTs: i.e., A. fulgidus accumulates predominantly sn-glycero-1-phospho-3-l-myo-inositol, while Aq. aeolicus accumulates sn-glycero-3-phospho-3-l-myo-inositol. IMPORTANCE: Compatible solutes of hyperthermophiles show high efficacy in thermal protection of proteins in comparison with solutes typical of mesophiles; therefore, they are potentially useful in several biotechnological applications. Glycerophosphoinositol (GPI) is synthesized from CDP-glycerol and l-myo-inositol 1-phosphate in a few hyperthermophiles. In this study, the molecular configuration of the GPI stereoisomers accumulated by members of the Bacteria and Archaea was established. The stereospecificity of glycerol phosphate cytidylyltransferase (GCT), the enzyme catalyzing the synthesis of CDP-glycerol, is crucial to the stereochemistry of GPI. However, the stereospecific properties of GCTs have not been investigated thus far. We devised a method to characterize GCT stereospecificity which does not require sn-glycerol 1-phosphate, a commercially unavailable substrate. This led us to understand the biochemical basis for the distinct GPI stereoisomer composition observed in archaea and bacteria.
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Archaeoglobus/enzimología , Bacterias/enzimología , Citidina Trifosfato/metabolismo , Fosfatos de Inositol/química , Nucleotidiltransferasas/metabolismo , Archaeoglobus/genética , Archaeoglobus/metabolismo , Bacterias/genética , Bacterias/metabolismo , Citidina Trifosfato/química , Glicerol/metabolismo , Fosfatos de Inositol/metabolismo , Espectroscopía de Resonancia Magnética , Conformación Molecular , Nucleotidiltransferasas/química , Proteínas Recombinantes/metabolismo , Estereoisomerismo , Especificidad por SustratoRESUMEN
BACKGROUND: Handgrip strength is used to identify sarcopenia and frailty phenotypes, being a potential predictor of mortality in older adults. However, uniformity is lacking in the reference values. This study aimed to describe handgrip strength values of older population aged ≥65 years in Portugal, considering the possible influence of anthropometric parameters. METHODS: A cross-sectional study was conducted in Portugal, among 1500 older adults aged ≥65 years old, according to "The Nutrition UP 65 Study Protocol". Demographic data were collected and cognitive performance, subjective general health, physical activity, anthropometric parameters and nutritional status were assessed and analysed. Handgrip strength data was obtained with a Jamar dynamometer. A Pubmed/Medline search was carried out to compare handgrip strength data between Portuguese older adults and other older populations. RESULTS: Handgrip strength was higher among men than among women (30.3 ± 9.2 Kgf vs 18 ± 5.4 Kgf, p < 0.001, respectively). In general, handgrip strength values of Portuguese older adults were lower than other older populations. In our sample, age, cognitive and nutritional status, self-reported sitting time and practice of physical activity were significantly correlated with handgrip strength in both sexes. Concerning anthropometric parameters, height was the most significantly correlated with handgrip strength (r = 0.34, p < 0.001, in women and r = 0.40, p < 0.001, in men). CONCLUSION: This study described, for the first time, handgrip strength values of Portuguese population aged ≥65 years, according to age and to sex-specific tertiles of height. The definition of handgrip strength reference values in this age group merits further reflection.
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Antropometría/métodos , Fuerza de la Mano , Competencia Mental , Sarcopenia , Anciano , Estudios Transversales , Autoevaluación Diagnóstica , Ejercicio Físico , Femenino , Evaluación Geriátrica/métodos , Humanos , Masculino , Estado Nutricional , Portugal/epidemiología , Valores de Referencia , Proyectos de Investigación , Sarcopenia/diagnóstico , Sarcopenia/epidemiología , Sarcopenia/fisiopatología , Sarcopenia/psicología , Factores Sexuales , Estadística como AsuntoRESUMEN
BACKGROUND: The older population is a risk group for hypovitaminosis D. The Ultraviolet Index (UVI) can be an indicator of potential for cutaneous synthesis of vitamin D but physiological and other environmental factors also influence vitamin D synthesis and status. Knowledge about vitamin D status in Portuguese older adults is limited. This study aims to explore the association between Ultraviolet Index and serum 25-hidroxyvitamin D3 [25(OH)D] levels accounting for other potential influential factors. METHODS: A cross-sectional study was conducted between December 2015 and June 2016, in 1497 Portuguese older adults (≥ 65 years) within Nutrition UP 65 project. For each participant, serum 25(OH)D was determined and the mean UVI (mUVI) in the respective residence district was calculated for the previous 30 days. Stepwise linear regression analyses were conducted for the following periods of blood collection: between December and June, December and March and April and June. Standardized regression coefficients (Sß) and 95% confidence intervals were calculated. RESULTS: The median 25(OH)D concentration was 35.9 nmol/L. The UVI was independently and positively associated with 25(OH)D in the models for December-June (Sß = 0.244, 95% CI: 0.198; 0.291, P < 0.001) and April-June (Sß = 0.295, 95% CI: 0.299; 0.362, P < 0.001) and independently and negatively associated in December-March period (Sß = -0.149, 95% CI: -0.211; -0.087, P < 0.001). CONCLUSIONS: In this sample with high vitamin D deficiency frequency, the UVI was a predictor of 25(OH)D levels but the direction of the association varied according to the blood collection period. Our results suggest that accounting for the time of year in future research regarding vitamin status and related public health recommendations may be relevant.