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1.
Hum Reprod ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39018559

RESUMEN

STUDY QUESTION: What is the risk of an undetected natural conception pregnancy during luteal phase ovarian stimulation, and how does it impact the pregnancy's course? SUMMARY ANSWER: The risk for an undetected, natural conception pregnancy in luteal phase ovarian stimulation is low and it appears that ovarian stimulation is unlikely to harm the pregnancy. WHAT IS KNOWN ALREADY: Random start ovarian stimulation appears to be similarly effective as early follicular stimulation start; and it allows ovarian stimulation to be started independent of the cycle day and throughout the cycle, in accordance with the patients' and clinics' schedule as long as there is no intention of a fresh embryo transfer in the same cycle. Starting ovarian stimulation in the luteal phase bears the possibility of an-at the timepoint of stimulation start-undetected, natural conception pregnancy that has already occurred. There is scarce data on the incidence of this event as well as on the possible implications of ovarian stimulation on the course of an existing pregnancy. STUDY DESIGN, SIZE, DURATION: This retrospective observational study, performed between June 2017 and January 2024, analyzed luteal phase stimulations, in which a natural conception pregnancy was detected during the ovarian stimulation treatment for IVF/ICSI. Luteal phase stimulation was defined as ovarian stimulation started after ovulation and before the next expected menstrual bleeding, with a serum progesterone (P4) level of >1.5 ng/ml on the day of stimulation start or 1 day before. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women who underwent a luteal phase ovarian stimulation in a tertiary referral ART center. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 488 luteal phase stimulation cycles were included in the analysis. Luteal phase stimulation was only started after a negative serum hCG measurement on the day or 1 day before commencement of ovarian stimulation. Ten patients (2.1%) had an undetected natural conception pregnancy at the time of luteal phase stimulation start. Eight of these patients underwent an ovarian stimulation in a GnRH-antagonist protocol and two in a progestin-primed stimulation protocol (PPOS). Recombinant FSH was used as stimulation medication for all patients, the patients with a PPOS protocol received additional recombinant LH. One pregnancy (0.2%) was detected after the oocyte retrieval, the other nine pregnancies were detected either due to persistent high serum progesterone levels or due to an increasing progesterone level after an initial decrease before oocyte retrieval. In the cycles with an undetected natural conception pregnancy, the median number of stimulation days was 8 days (range: 6-11 days) and median serum hCG at detection of pregnancy was 59 IU hCG (range: 14.91-183.1). From 10 patients with a pregnancy, three patients delivered a healthy baby, two patients had ongoing pregnancies at the time of summarizing the data, three patients had biochemical pregnancies (patient age: 30, 39, and 42 years), one patient had an ectopic pregnancy which required a salpingectomy, and one patient (age: 34 years) had an early pregnancy loss. LIMITATIONS, REASONS FOR CAUTION: The retrospective study design and the small sample size can limit the accuracy of the estimates. WIDER IMPLICATIONS OF THE FINDINGS: Overall, there is a small risk of undetected natural conception pregnancies when luteal phase stimulation is undertaken. It appears that there are no adverse effects through either direct effect on the embryo or indirectly through a detrimental effect on the corpus luteum function on the pregnancy in our cohort. STUDY FUNDING/COMPETING INTEREST(S): This study did not receive funding. The authors declare that there is no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.

2.
Reprod Biomed Online ; 49(2): 104074, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38865782

RESUMEN

RESEARCH QUESTION: Is female age a significant factor in the likelihood of an ongoing pregnancy in single euploid frozen embryo transfers (FET)? DESIGN: Retrospective study of 1923 single euploid FET cycles in 1464 women, either in a natural cycle or a hormone replacement therapy cycle. The primary outcome was the ongoing pregnancy rate (OPR). RESULTS: There were 990 (51.48%) ongoing pregnancies among 1923 included transfers. The OPR were 51.4%, 49.1%, 53.3% and 52.3% for women aged ≤35, >35-≤37, >37-≤40 and >40 years at oocyte retrieval (OCR), without a significant trend for decreasing OPR (P = 0.679). No significant differences in female age at embryo transfer (P = 0.609) and female age at OCR (P = 0.816) were found between the groups (ongoing pregnancy versus no pregnancy or miscarriage). Women who received good-quality embryos (P < 0.001), had a lower body mass index (BMI) (P < 0.001), had achieved at least one pregnancy previously (P < 0.001), and underwent natural cycle endometrial preparation (P < 0.001) were more likely to achieve an ongoing pregnancy. Multivariable regression analysis (adjusted for BMI, embryo quality and endometrial preparation) did not show a significant effect of female age at OCR on achieving an ongoing pregnancy. Compared with women aged ≤35 years, none of the age groups had significantly higher or lower OPR. A multinomial regression analysis showed that BMI, embryo quality and endometrial preparation were associated with miscarriage/no pregnancy versus ongoing pregnancy (P = 0.001, 0.001 and 0.001, respectively). Female age had no significant association with either outcome. CONCLUSIONS: Female age in itself does not have a substantial impact on the OPR in single euploid FET cycles, but the OPR is impacted significantly by embryo quality, BMI, previous parity, and a natural cycle endometrial preparation protocol.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38348612

RESUMEN

OBJECTIVE: To evaluate whether trigger and oocyte collection at a smaller follicle size decreases the risk of premature ovulation while maintaining the reproductive potential of oocytes in women with a severely diminished ovarian reserve undergoing modified natural-cycle in-vitro fertilization. METHODS: This was a retrospective cohort study including women who had at least one unsuccessful cycle (due to no response) of conventional ovarian stimulation with a high dosage of gonadotropins and subsequently underwent a modified natural cycle with a solitary growing follicle (i.e. only one follicle > 10 mm at the time of trigger). The association between follicle size at trigger and various cycle outcomes was tested using regression analyses. RESULTS: A total of 160 ovarian stimulation cycles from 110 patients were included in the analysis. Oocyte pick-up (OPU) was performed in 153 cycles and 7 cycles were canceled due to premature ovulation. Patients who received their trigger at smaller follicle sizes (≤ 15 mm) had significantly lower rates of premature ovulation and thus higher rates of OPU (98.9% vs 90.8%; odds ratio, 9.56 (95% CI, 1.58-182.9); P = 0.039) compared with those who received their trigger at larger follicle sizes (> 15 mm). On multivariable analysis, smaller follicle sizes at trigger (> 10 to 13 mm, > 13 to 15 mm, > 15 mm to 17 mm) were not associated significantly with a lower rate of cumulus-oocyte complex (COC) retrieval, metaphase-II (MII) oocytes or blastulation when compared to the > 17-mm group. On sensitivity analysis including only the first cycle of each couple, the maturity rate among those with COC retrieval was highest in follicle sizes > 15 to 17 mm (92.3%) and > 13 to 15 mm (91.7%), followed by > 10 to 13 mm (85.7%) and lowest in the > 17-mm group (58.8%). During the study period, five euploid blastocysts developed from 48 fertilized MII oocytes with follicle sizes of 12 mm (n = 3), 14 mm (n = 1) and 16 mm (n = 1) at trigger. Of those, four were transferred and resulted in two live births, both of which developed from follicles with a size at trigger of 12 mm. CONCLUSIONS: The ideal follicle size for triggering oocyte maturation may be smaller in women with a severely diminished ovarian reserve managed on a modified natural cycle when compared to conventional cut-offs. The risk of OPU cancellation was significantly higher in women triggered at follicle size > 15 mm and the yield of mature oocytes was not adversely affected in women triggered at follicle size > 13 to 15 mm compared with > 15 to 17 mm. Waiting for follicles to reach sizes > 17mm may be detrimental to achieving optimal outcome. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

4.
J Assist Reprod Genet ; 41(4): 885-892, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38372882

RESUMEN

PURPOSE: To evaluate the role of serum progesterone (P4) on the day of embryo transfer (ET) when dydrogesterone (DYD) and micronized vaginal progesterone (MVP) are combined as luteal phase support (LPS) in a hormone replacement therapy (HRT) frozen ET (FET) cycles. METHODS: Retrospective study, including single euploid HRT FET cycles with DYD and MVP as LPS and P4 measurement on ET day. Initially, patients with P4 levels < 10 ng/ml increased MVP to 400 mg/day; this "rescue" was abandoned later. RESULTS: 560 cycles of 507 couples were included. In 275 women, serum P4 level was < 10 ng/ml on the ET day. Among those with low P4 levels, MVP dose remained unchanged in 65 women (11.6%) and was increased in 210 women (37.5%). Women with P4 levels ≥ 10 ng/ml continued LPS without modification. Overall pregnancy rates in these groups were 61.5% (40/65), 54.8% (115/210), and 48.4% (138/285), respectively (p = n.s.). Association of serum P4 levels with ongoing pregnancy rates was analyzed in women without any additional MVP regardless of serum P4 levels (n = 350); multivariable analysis (adjusted for age, BMI, embryo quality (EQ)) did not show a significant association of serum P4 levels with OPR (OR 0.96, 95% CI 0.90-1.02; p = 0.185). Using inverse probability treatment weights, regression analysis in the weighted sample showed no significant association between P4 treatment groups and OP. Compared to fair EQ, the transfer of good EQ increased (OR 1.61, 95% CI 1.22-2.15; p = 0.001) and the transfer of a poor EQ decreased the odds of OP (OR 0.73, 95% CI 0.55-0.97; p = 0.029). CONCLUSION: In HRT FET cycle, using LPS with 300 mg/day MVP and 30 mg/day DYD, it appears that serum P4 measurement and increase of MVP in patients with P4 < 10 ng/ml are not necessary.


Asunto(s)
Didrogesterona , Transferencia de Embrión , Terapia de Reemplazo de Hormonas , Índice de Embarazo , Progesterona , Humanos , Femenino , Didrogesterona/administración & dosificación , Progesterona/sangre , Transferencia de Embrión/métodos , Adulto , Embarazo , Terapia de Reemplazo de Hormonas/métodos , Estudios Retrospectivos , Administración Intravaginal , Fertilización In Vitro/métodos , Fase Luteínica/efectos de los fármacos
5.
Hum Reprod ; 38(7): 1318-1324, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37196321

RESUMEN

STUDY QUESTION: Are serum progesterone (P4) levels on the embryo transfer (ET) day predictive of ongoing pregnancy (OP) following a single euploid blastocyst transfer in a natural cycle (NC) when luteal phase support is routinely given? SUMMARY ANSWER: In single euploid frozen ETs in NC, P4 levels on ET day are not predictive for OP, when luteal phase support (LPS) is routinely added after the ET. WHAT IS KNOWN ALREADY: In an NC frozen embryo transfer (FET), P4 produced by the corpus luteum initiates secretory transformation of the endometrium and maintains pregnancy after implantation. There are ongoing controversies on the existence of a P4 cutoff level on the ET day, being predictive for the chance of OP as well as of the possible role of additional LPS after ET. Previous studies in NC FET cycles, evaluating and identifying P4 cutoff levels did not exclude embryo aneuploidy as a possible reason for failure. STUDY DESIGN, SIZE, DURATION: This retrospective study analyzed single, euploid FET in NC, conducted in a tertiary referral IVF centre between September 2019 and June 2022, for which measurement of P4 on the day of ET and the treatment outcomes were available. Patients were only included once into the analysis. Outcome was defined as OP (ongoing clinical pregnancy with heartbeat, >12 weeks) or no-OP (not pregnant, biochemical pregnancy, early miscarriage). PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients with an ovulatory cycle and a single euploid blastocyst in an NC FET cycle were included. Cycles were monitored by ultrasound and repeated measurement of serum LH, estradiol, and P4. LH surge was identified when a rise of 180% above the previous level occurred and P4 levels of ≥1.0 ng/ml were regarded as confirmation of ovulation. The ET was scheduled on the fifth day after P4 rise and vaginal micronized P4 was started on the day of ET after P4 measurement. MAIN RESULTS AND THE ROLE OF CHANCE: Of 266 patients included, 159 (59.8%) patients had an OP. There was no significant difference between the OP- and no-OP-groups for age, BMI, and day of embryo biopsy/cryopreservation (Day 5 versus Day 6). Furthermore, P4 levels were not different between the groups of patients with OP (P4: 14.8 ng/ml (IQR: 12.0-18.5 ng/ml)) versus no-OP (P4: 16.0 ng/ml (IQR: 11.6-18.9 ng/ml)) (P = 0.483), and no differences between both groups, when P4 levels were stratified into categories of P4 levels of >5 to ≤10, >10 to ≤15, >15 to ≤20, and >20 ng/ml (P = 0.341). However, both groups were significantly different for the embryo quality (EQ), defined by inner cell mass/trophectoderm, as well as when stratified into three EQ groups (good, fair, and poor) (P = 0.001 and 0.002, respectively). Stratified EQ groups remained the only significant parameter influencing OP in the uni- and multivariate analyses (P = 0.002 and P = 0.004, respectively), including age, BMI, and P4 levels (each in categories) and embryo cryopreservation day. Receiver operator characteristic curve for the prediction of an OP revealed an AUC of 0.648 when age, BMI and EQ groups were included into the model. The inclusion of P4 measurement on ET day into the model did not add any benefit for OP prediction (AUC = 0.665). LIMITATIONS, REASONS FOR CAUTION: The retrospective design is a limitation. WIDER IMPLICATIONS OF THE FINDINGS: Monitoring serum P4 levels can be abandoned in NC FET cycles with routine LPS as they do not seem to be predictive of live birth. STUDY FUNDING/COMPETING INTEREST(S): No external funding was used for this study. The authors state that they do not have any conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Fase Luteínica , Progesterona , Femenino , Embarazo , Humanos , Índice de Embarazo , Estudios Retrospectivos , Lipopolisacáridos , Transferencia de Embrión/métodos
6.
Hum Reprod ; 38(8): 1473-1483, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37344149

RESUMEN

STUDY QUESTION: Which patients might benefit from insemination of delayed-matured oocytes? SUMMARY ANSWER: Delayed-matured oocytes had a ≥50% contribution to the available cohort of biopsied blastocysts in patients with advanced maternal age, low maturation, and/or low fertilization rates. WHAT IS KNOWN ALREADY: Retrieved immature oocytes that progress to the MII stage in vitro could increase the number of embryos available during ICSI cycles. However, these delayed-matured oocytes are associated with lower fertilization rates and compromised embryo quality. Data on the ploidy of these embryos are controversial, but studies failed to compare euploidy rates of embryos derived from delayed-matured oocytes to patients' own immediate mature sibling oocytes. This strategy efficiently allows to identify the patient population that would benefit from this approach. STUDY DESIGN, SIZE, DURATION: This observational study was performed between January 2019 and June 2021 including a total of 5449 cumulus oocytes complexes from 469 ovarian stimulation cycles, from which 3455 inseminated matured oocytes from ICSI (n = 2911) and IVF (n = 544) were considered as the sibling controls (MII-D0) to the delayed-matured oocytes (MII-D1) (n = 910). Euploidy rates were assessed between delayed-matured (MII-D1) and mature sibling oocytes (MII-D0) in relation to patients' clinical characteristics such as BMI, AMH, age, sperm origin, and the laboratory outcomes, maturation, fertilization, and blastocyst utilization rates. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 390 patients undergoing IVF/ICSI, who had at least one metaphase I (MI) or germinal-vesicle (GV) oocyte on the day of oocyte collection (Day 0), which matured in 20-28 h after denudation were included. MI and GV oocytes that matured overnight were inseminated on the following day (Day 1, MII-D1) by ICSI. Only cycles planned for preimplantation genetic testing for aneuploidy using fresh own oocytes were included. MAIN RESULTS AND THE ROLE OF CHANCE: Fertilization (FR) and blastocyst utilization rates were significantly higher for MII-D0 compared to delayed-matured oocytes (MII-D1) (69.5% versus 55.9%, P < 0.001; and 59.5% versus 18.5%, P < 0.001, respectively). However, no significant difference was observed in the rate of euploid embryos between MII-D0 and MII-D1 (46.3% versus 39.0%, P = 0.163). For evaluation of the benefit of inseminating MI/GV oocytes on D1 per cycle in relation to the total number of biopsied embryos, cycles were split into three groups based on the proportion of MII-D1 embryos that were biopsied in that cycle (0%, 1-50%, and ≥50%). The results demonstrate that patients who had ≥50% contribution of delayed-matured oocytes to the available cohort of biopsied embryos were those of advanced maternal age (mean age 37.7 years), <10 oocytes retrieved presenting <34% maturation rate, and <60% fertilization rate. Every MII oocyte injected next day significantly increased the chances of obtaining a euploid embryo [odds ratio (OR) = 1.83, CI: 1.50-2.24, P < 0.001] among MII-D1. The odds of enhanced euploidy were slightly higher among the MII-D1-GV matured group (OR = 1.78, CI: 1.42-2.22, P < 0.001) than the MII-D1-MI matured group (OR = 1.54, CI: 1.25-1.89, P < 0.001). Inseminating at least eight MII-D1 would have >50% probability of getting a euploid embryo among the MII-D1 group. LIMITATIONS, REASONS FOR CAUTION: ICSI of MII-D1 was performed with the fresh or frozen ejaculates or testicular samples from the previous day. The exact timing of polar body extrusion of delayed-matured MI/GV was not identified. Furthermore, the time point of the final oocyte maturation to MII for the immature oocytes and for the oocytes inseminated by IVF could not be identified. WIDER IMPLICATIONS OF THE FINDINGS: The results of this study might provide guidance to the IVF laboratories for targeting the patient's population who would benefit from MII-D1 ICSI without adhering to unnecessary costs and workload. STUDY FUNDING/COMPETING INTEREST(S): No external funding was received for this study. There are no conflicts of interest to be declared for any of the authors. There are no patents, products in development, or marketed products to declare. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Oocitos , Semen , Humanos , Masculino , Aneuploidia , Blastocisto , Evaluación de Resultado en la Atención de Salud , Estudios Retrospectivos , Fertilización In Vitro
7.
J Investig Allergol Clin Immunol ; 32(2): 116-123, 2022 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-32856591

RESUMEN

BACKGROUND: Component-resolved diagnosis plays a key role in the diagnosis and treatment of honeybee venom allergy (HVA). Our aim was to study whether any of the allergens not included in the usual diagnostic platforms are relevant in our population. MATERIAL AND METHODS: The allergenic sensitization profile of Spanish patients who experienced a systemic reaction after a honeybee sting and were diagnosed with HVA was studied by immunoblotting based on raw autochthonous Apis mellifera venom characterized using SDS-PAGE and mass spectrometry and a commercial assay (ImmunoCAP). RESULTS: Allergens in the International Union of Immunological Societies database were detected in the raw A mellifera venom extract used, except Api m 12. Sera from 51 patients with a median (IQR) age of 46.2 years (35.6-54.6) were analyzed. ImmunoCAP revealed Api m 1 and Api m 10 to be major allergens (88.2% and 74.5%, respectively). Moreover, Api m 6 (85.4%) was detected by immunoblotting. CONCLUSION: Api m 1, Api m 6, and Api m 10 are major A mellifera venom allergens in our population.


Asunto(s)
Venenos de Abeja , Hipersensibilidad , Mordeduras y Picaduras de Insectos , Alérgenos , Animales , Abejas , Humanos , Hipersensibilidad/diagnóstico , Inmunoglobulina E , Persona de Mediana Edad
8.
Phys Rev Lett ; 120(12): 120602, 2018 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-29694098

RESUMEN

Quantum systems strongly coupled to many-body systems equilibrate to the reduced state of a global thermal state, deviating from the local thermal state of the system as it occurs in the weak-coupling limit. Taking this insight as a starting point, we study the thermodynamics of systems strongly coupled to thermal baths. First, we provide strong-coupling corrections to the second law applicable to general systems in three of its different readings: As a statement of maximal extractable work, on heat dissipation, and bound to the Carnot efficiency. These corrections become relevant for small quantum systems and vanish in first order in the interaction strength. We then move to the question of power of heat engines, obtaining a bound on the power enhancement due to strong coupling. Our results are exemplified on the paradigmatic non-Markovian quantum Brownian motion.

9.
Nutr Metab Cardiovasc Dis ; 28(2): 133-142, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29329923

RESUMEN

BACKGROUND AND AIMS: High-protein (HP) diets have shown benefits in cardiometabolic markers such as insulin or triglycerides but the responsible mechanisms are not known. We aimed to assess the effect of three energy-restricted diets with different protein contents (20%, 27%, and 35%; ∼80% coming from animal source) on plasma adipokine concentration and its association with changes in cardiometabolic markers. METHODS: Seventy-six women (BMI 32.8 ± 2.93) were randomized to one of three calorie-reduced diets, with protein, 20%, 27%, or 35%; carbohydrates, 50%, 43%, or 35%; and fat, 30%, for 3 months. Plasma adipokine (leptin, resistin, adiponectin, and retinol-binding protein 4; RBP4) levels were assessed. RESULTS: After 3 months, leptin concentration decreased in all groups without differences among them, while resistin levels remained unchanged. Adiponectin concentration heterogeneously changed in all groups (P for trend = 0.165) and resistin concentration did not significantly change. RPB4 significantly decreased by -17.5% (-31.7, -3.22) in 35%-protein diet (P for trend = 0.024 among diets). Triglycerides improved in women following the 35%-protein diet regardless of weight loss; RBP4 variation significantly influenced triglyceride concentration change by 24.9% and 25.9% when comparing 27%- and 35%- with 20%-protein diet, respectively. CONCLUSIONS: A 35%-protein diet induced a decrease in RBP4 regardless of weight loss, which was directly associated with triglyceride concentration improvement. These findings suggest that HP diets improve the cardiometabolic profile, at least in part, through changes in adipokine secretion. Whether this beneficial effect of HP diet is due to improvements in hepatic or adipose tissue functionality should be elucidated. CLINICAL TRIAL REGISTRATION: The clinical trial has been registered in ClinicalTrials.gov (Identifier: NCT02160496).


Asunto(s)
Adipoquinas/sangre , Restricción Calórica , Proteínas en la Dieta/administración & dosificación , Obesidad/dietoterapia , Pérdida de Peso , Adiponectina/sangre , Adulto , Biomarcadores/sangre , Proteínas en la Dieta/metabolismo , Femenino , Humanos , Leptina/sangre , Persona de Mediana Edad , Obesidad/sangre , Obesidad/diagnóstico , Obesidad/fisiopatología , Resistina/sangre , Proteínas Plasmáticas de Unión al Retinol/metabolismo , España , Factores de Tiempo , Resultado del Tratamiento , Triglicéridos/sangre
10.
Nutr Metab Cardiovasc Dis ; 25(9): 853-859, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26232911

RESUMEN

BACKGROUND AND AIM: Different kinds of fatty acids can affect the synthesis, absorption, and elimination of cholesterol. This study was carried out to assess the associations of cholesterol metabolism with the intake of two meats with different fatty acid composition in healthy volunteers. METHODS AND RESULTS: The study group was composed of 20 subjects (12 males and eight females; age, 34.4 ± 11.6 years; body mass index (BMI), 23.5 ± 2.3 kg/m(2); low-density lipoprotein (LDL) cholesterol, 2.97 ± 0.55 mmol/l; high-density lipoprotein (HDL) cholesterol, 1.61 ± 0.31 mmol/l; triglycerides (TG), 1.06 ± 0.41 mmol/l) who completed a 30-day randomized and cross-over study to compare the cholesterol metabolism effect of 250 g of low-fat lamb versus 250 g of high-fat lamb per day in their usual diet. Cholesterol absorption, synthesis, and elimination were estimated from the serum non-cholesterol sterol and oxysterol concentrations analyzed by a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). No changes in weight, plasma lipids, or physical activity were observed across the study. Cholesterol intestinal absorption was decreased with both diets. Cholesterol synthesis and elimination decreased during the low-fat lamb dietary intervention (ρ = 0.048 and ρ = 0.005, respectively). CONCLUSION: Acute changes in the diet fat content modify the synthesis, absorption, and biliary elimination of cholesterol. These changes were observed even in the absence of total and LDL cholesterol changes in plasma. REGISTRATION NUMBER FOR CLINICAL TRIALS: ClinicalTrials.gov PRS, NCT02259153.


Asunto(s)
Carne Roja , Esteroles/sangre , Adulto , Apolipoproteína A-I/sangre , Apolipoproteínas B/sangre , Biomarcadores/sangre , Glucemia/metabolismo , Índice de Masa Corporal , Peso Corporal , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Cromatografía Líquida de Alta Presión , Estudios Cruzados , Grasas de la Dieta/administración & dosificación , Grasas de la Dieta/análisis , Ingestión de Energía , Ácidos Grasos/análisis , Ácidos Grasos Monoinsaturados/análisis , Ácidos Grasos Insaturados/análisis , Femenino , Humanos , Absorción Intestinal , Masculino , Persona de Mediana Edad , Actividad Motora , Método Simple Ciego , Espectrometría de Masas en Tándem , Triglicéridos/sangre , Adulto Joven
11.
Analyst ; 139(12): 2944-67, 2014 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-24779027

RESUMEN

Carbohydrates fulfil many common as well as extremely important functions in nature. They show a variety of molecular displays--e.g., free mono-, oligo-, and polysaccharides, glycolipids, proteoglycans, glycoproteins, etc.--with particular roles and localizations in living organisms. Structure-specific peculiarities are so many and diverse that it becomes virtually impossible to cover them all from an analytical perspective. Hence this manuscript, focused on mammalian glycosylation, rather than a complete list of analytical descriptors or recognized functions for carbohydrate structures, comprehensively reviews three central issues in current glycoscience, namely (i) structural analysis of glycoprotein glycans, covering both classical and novel approaches for teasing out the structural puzzle as well as potential pitfalls of these processes; (ii) an overview of functions attributed to carbohydrates, covering from monosaccharide to complex, well-defined epitopes and full glycans, including post-glycosylational modifications, and (iii) recent technical advances allowing structural identification of glycoprotein glycans with simultaneous assignation of biological functions.


Asunto(s)
Proteínas/metabolismo , Animales , Glicosilación , Mamíferos , Proteínas/química , Relación Estructura-Actividad
12.
Invest New Drugs ; 31(6): 1573-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24077981

RESUMEN

BACKGROUND: Cisplatin and fluoropyrimidine (CF) are standard first- line treatment in advanced gastric cancer, but no second-line treatment has yet been established. We present a phase II study in which we evaluated the efficacy and toxicity of the combination of Sorafenib (S), and Oxaliplatin as second-line therapy. METHODS: Patients with progressive gastric adenocarcinoma after CF- first-line, ECOG 0-2, and measurable disease were included. The primary objective was PFS. Treatment doses were Oxaliplatin 130 mg/m²/3 weeks and Sorafenib 800 mg/bid/d. RESULTS: We included 40 patients. CR was 2.5% and SD was 47.2%. Grade 3-4 toxic effects were neutropenia (9.8%), thrombocytopenia (7.3%), neurotoxicity (4.9%) and diarrhea (4.9%). Median PFS was 3 months (95%CI: 2.3-4.1) and median OS was 6.5 months (95% CI: 5.2-9.6). Time to progression (TTP) to first line therapy was a prognosis factor. Median OS was 9.7 months when time-to-progression during first-line chemotherapy was >6 months and 5.6 m when it was <6 months (p = 0.04). CONCLUSIONS: Time-to-progression under a CF-based first-line therapy determines subgroups of GC patients with different prognosis. The combination of Oxaliplatin-Sorafenib in advanced GC patients previously treated with CF appears safe, but our results do not support the implementation of a phase III trial.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias Gástricas/tratamiento farmacológico , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Capecitabina , Cisplatino/administración & dosificación , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/análogos & derivados , Humanos , Masculino , Persona de Mediana Edad , Niacinamida/administración & dosificación , Niacinamida/análogos & derivados , Compuestos Organoplatinos/administración & dosificación , Oxaliplatino , Compuestos de Fenilurea/administración & dosificación , Sorafenib , Resultado del Tratamiento
13.
Ann Oncol ; 23(3): 664-670, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21652581

RESUMEN

BACKGROUND: Based on a phase I study showing the feasibility of combining of oxaliplatin, cisplatin, and 5-fluorouracil (5-FU) (OCF) with radiation therapy (RT) in esophageal cancer, the efficacy of this regimen in esophageal, gastroesophageal (GE), and gastric (G) cancer was assessed in this phase II multicenter study. PATIENTS AND METHODS: Patients with resectable tumors were eligible. Treatment included two cycles of oxaliplatin 85 mg/m(2), cisplatin 55 mg/m(2), and continuously infused 5-FU 3 g/m(2) in 96 h and concurrent RT (45 Gy), followed by surgery after 6-8 weeks. Primary end point was complete pathologic response (pCR). RESULTS: Forty-one patients were enrolled. Tumor location was esophagus 39% (squamous 10/adenocarcinoma 6), GE junction 32%, and stomach 29%. G3-G4 adverse events included asthenia (27%) and neutropenia (14%). One toxic death occurred. Thirty-one patients (75.6%) underwent surgery (R0 in 94%). Pathologic response was achieved in 58% of patients, with pCR in 50% and 16% of esophageal and GE/G cancer, respectively. pCR was achieved in 67% of squamous cell carcinoma. Survival: median follow-up, 50.4 months; median progression-free survival and overall survival were 23.2 and 28.4 months, respectively. CONCLUSION: Preoperative OCF plus RT showed an acceptable toxicity and promising activity especially in squamous cell esophageal cancer.


Asunto(s)
Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/terapia , Quimioradioterapia , Neoplasias Esofágicas/terapia , Terapia Neoadyuvante/métodos , Neoplasias Gástricas/terapia , Adenocarcinoma/patología , Adulto , Anciano , Carcinoma de Células Escamosas/patología , Quimioradioterapia/métodos , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Supervivencia sin Enfermedad , Neoplasias Esofágicas/patología , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/efectos adversos , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Compuestos Organoplatinos/administración & dosificación , Compuestos Organoplatinos/efectos adversos , Oxaliplatino , Neoplasias Gástricas/patología
14.
Nutr Metab Cardiovasc Dis ; 22(7): 591-7, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21196102

RESUMEN

BACKGROUND AND AIMS: Familial hypercholesterolaemia (FH) and familial combined hyperlipidaemia (FCH) are common atherogenic disorders with great variability in cardiovascular disease (CVD). No direct atherosclerosis burden comparisons have been performed between FH and FCH in relation to lipoprotein particle distribution. METHODS AND RESULTS: Risk factors and three measures of carotid intima-media thickness (IMT) in both sides were determined in 572 FH, 250 FCH and 200 controls. Lipoproteins were assessed by nuclear magnetic resonance (NMR) spectroscopy. Compared with controls, IMT measures were increased in FH and FCH. FCH had the highest adjusted mean-maximum IMT. FH had twice low-density lipoprotein (LDL) particles than controls, but similar LDL subclass size and distribution. FCH subjects also had increased LDL particles and the highest number of small LDL (1519 ± 731 nmol l(-1) vs. 887 ± 784 nmol l(-1) in FH and 545 ± 409 nmol l(-1) in controls). Age, gender, cholesterol/high-density lipoprotein (HDL) ratio, smoking and systolic blood pressure were independently associated with IMT in FH (r(2) = 0.38). The same variables, except cholesterol/HDL ratio, were associated with IMT in FCH (r(2) = 0.40). Among NMR lipoproteins, only VLDL and chylomicrons increased IMT prediction in FCH by 0.8%. CONCLUSION: FH and FCH subjects show increased carotid atherosclerosis in relation to classical risk factors. Lipoprotein subclasses do not substantially contribute to IMT variability.


Asunto(s)
Enfermedades de las Arterias Carótidas/sangre , Hiperlipidemia Familiar Combinada/sangre , Hiperlipoproteinemia Tipo II/sangre , Adolescente , Adulto , Anciano , Presión Sanguínea , Enfermedades de las Arterias Carótidas/fisiopatología , Grosor Intima-Media Carotídeo , Estudios de Casos y Controles , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Femenino , Humanos , Hiperlipidemia Familiar Combinada/fisiopatología , Hiperlipoproteinemia Tipo II/fisiopatología , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Adulto Joven
15.
Food Chem ; 371: 131144, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34560334

RESUMEN

The effect of LEDs light on the formation of volatile sulfur compounds (VSCs) and the final sensory quality of white and rosé wines was evaluated. Thus, different commercial wines were exposed for ten days to three types of lights. All wine samples were analyzed throughout the exposure period to determine the usual oenological parameters together with some other chemical characteristics (color evolution; riboflavin, cysteine and methionine photodegradation), VSC amounts and sensory characteristics. The results showed that the wines exposed to ultraviolet light suffered greater degradation of the aromatic precursors, mainly riboflavin, and had higher concentrations of VSCs. Regarding LED lights, these produced minimal degradative effects. So that we can consider this type of light as an alternative to reduce the economic impact that currently occurs due to the photodegradation of bottled wines.


Asunto(s)
Vino , Compuestos de Azufre , Rayos Ultravioleta , Vino/análisis
16.
Front Bioeng Biotechnol ; 10: 815892, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35372298

RESUMEN

A comparative study was conducted on the efficiency of mercury removal using bacterial nanocellulose (BNC) membranes obtained from the fermentation of the microorganism Komagataeibacter medellinensis, in contrast with its oxidized analog obtained by modifying the bacterial nanocellulose membranes via oxidation with 2,2,6,6-Tetramethylpiperidine-1-oxyl. Both types of membranes (modified and unmodified) were characterized to identify variations in the Physico-chemical parameters after modification. FTIR spectra confirmed the chemical modification of cellulose in all reaction conditions by the presence of a new characteristic band at ∼1730 cm-1, corresponding to the new carboxylic groups produced by the oxidative process, and the decline of the band at ∼1,650 cm-1, corresponding to the hydroxyl groups of the C6 carbon. While the XRD profiles indicated that the percentage of BNC crystallinity decreased and the SEM images showed that the nanoribbon network was interrupted as the amount of oxidizing agent increased. The kinetics of mercury removal from both types of membrane was evaluated by calculating the concentration of mercury at different times and establishing a mathematical model to describe the kinetics of this process. The modified membranes improved significantly the adsorption process of the metal ion and it was found that the modification that results in the greatest adsorption efficiency was BNC-m 7.5 with a value of 92.97%. The results obtained suggest that the modification of the bacterial nanocellulose membranes by oxidation transcendentally improves the mercury removal capacity, outlining the modified membranes as an excellent material for mercury removal in wastewater.

17.
Med Phys ; 38(2): 983-92, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21452735

RESUMEN

PURPOSE: Electronic portal imaging devices (EPIDs) are increasingly used for IMRT dose verification, both pretreatment and in vivo. In this study, an earlier developed backprojection model has been modified to avoid the need for patient-specific transmission measurements and, consequently, leads to a faster procedure. METHODS: Currently, the transmission, an essential ingredient of the backprojection model, is estimated from the ratio of EPID measurements with and without a phantom/patient in the beam. Thus, an additional irradiation to obtain "open images" under the same conditions as the actual phantom/patient irradiation is required. However, by calculating the transmission of the phantom/patient in the direction of the beam instead of using open images, this extra measurement can be avoided. This was achieved by using a model that includes the effect of beam hardening and off-axis dependence of the EPID response on photon beam spectral changes. The parameters in the model were empirically obtained by performing EPID measurements using polystyrene slab phantoms of different thickness in 6, 10, and 18 MV photon beams. A theoretical analysis to verify the sensitivity of the model with patient thickness changes was performed. The new model was finally applied for the analysis of EPID dose verification measurements of step-and-shoot IMRT treatments of head and neck, lung, breast, cervix, prostate, and rectum patients. All measurements were carried out using Elekta SL20i linear accelerators equipped with a hydrogenated amorphous silicon EPID, and the IMRT plans were made using PINNACLE software (Philips Medical Systems). RESULTS: The results showed generally good agreement with the dose determined using the old model applying the measured transmission. The average differences between EPID-based in vivo dose at the isocenter determined using either the new model for transmission and its measured value were 2.6 +/- 3.1%, 0.2 +/- 3.1%, and 2.2 +/- 3.9% for 47 patients treated with 6, 10, and 18 MV IMRT beams, respectively. For the same group of patients, the differences in mean gamma analysis (3% maximum dose, 3 mm) were 0.16 +/- 0.26%, 0.21 +/- 0.24%, and 0.02 +/- 0.12%, respectively. For a subgroup of 11 patients, pretreatment verification was also performed, showing similar dose differences at the isocenter: -1.9 +/- 0.9%, -1.4 +/- 1.2%, and -0.4 +/- 2.4%, with somewhat lower mean gamma difference values: 0.01 +/- 0.09%, 0.01 +/- 0.07%, and -0.09 +/- 0.10%, respectively. Clinical implementation of the new model would save 450 h/yr spent in measurement of open images. CONCLUSIONS: It can be concluded that calculating instead of measuring the transmission leads to differences in the isocenter dose generally smaller than 2% (2.6% for 6 MV photon beams for in vivo dose) and yielded only slightly higher gamma-evaluation parameter values in planes through the isocenter. Hence, the new model is suitable for clinical implementation and measurement of open images can be omitted.


Asunto(s)
Equipos y Suministros Eléctricos , Radiometría/instrumentación , Radioterapia Asistida por Computador/instrumentación , Radioterapia de Intensidad Modulada/métodos , Calibración , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Neoplasias/radioterapia , Fotones/uso terapéutico
18.
Anal Bioanal Chem ; 401(2): 389-403, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21448606

RESUMEN

Doping analysis relies on the determination of prohibited substances that should not be present in the body of an athlete or that should be below a threshold value. In the case of xenobiotics their mere presence is sufficient to establish a doping offence. However, in the case of human biotics the analytical method faces the difficulty of distinguishing between endogenous and exogenous origin. For this purpose ingenious strategies have been implemented, often aided by state-of-the-art technological advancements such as mass spectrometry in all its possible forms. For larger molecules, i.e. protein hormones, the innate structural complexity, the heterogeneous nature, and the extremely low levels in biological fluids have rendered the analytical procedures heavily dependent of immunological approaches. Although approaches these confer specificity and sensitivity to the applications, most rely on the use of two, or even three, antibody incubations with the consequent increment in assay variability. Moreover, the requirement for different antibodies that separately recognise different epitopes in screening and confirmation assays further contributes to differences encountered in either measurement. The development of analytical techniques to measure interactions directly, such as atomic force microscopy, quartz crystal microbalance or surface plasmon resonance, have greatly contributed to the accurate evaluation of molecular interactions in all fields of biology, and expectations are that this will only increase. Here, an overview is provided of surface plasmon resonance, and its particular value in application to the field of doping analysis.


Asunto(s)
Doping en los Deportes , Hormonas Peptídicas/análisis , Detección de Abuso de Sustancias/métodos , Resonancia por Plasmón de Superficie , Humanos , Inmunoensayo , Hormonas Peptídicas/inmunología , Sensibilidad y Especificidad
19.
Chemosphere ; 271: 129399, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33482525

RESUMEN

The present study aimed to evaluate the effects of exposure for four months, with ibuprofen and triclosan at 25 and 50 µg/L in Striped catfish Pseudoplatystoma magdaleniatum, evaluated between sexes and exposure times. Biochemical biomarkers such as lactate dehydrogenase, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma-glutamyltransferase, acetylcholinesterase, creatine kinase, lipid peroxidation, albumin, globulins, creatinine, and urea were evaluated. The results of this study suggest that both ibuprofen and triclosan at concentrations of 25 and 50 µg/L can cause alterations to P. magdaleniatum, interfering with the activity of certain enzymes associated with energy production, immune response, architecture, and cellular physiology. Also, we determined the current state of contamination in fish, the concentration of ibuprofen and triclosan in P. magdaleniatum muscle samples from the different places markets located on the banks of the main rivers of Colombia was quantified by UHPLC-QqQ-MS/MS, in three climatic periods; finding triclosan levels in the dry season in some of the sampling points compatible with enzyme-level alterations in this species.


Asunto(s)
Bagres , Triclosán , Animales , Colombia , Ibuprofeno , Espectrometría de Masas en Tándem , Triclosán/toxicidad
20.
Mol Genet Genomics ; 283(6): 565-74, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20428891

RESUMEN

Familial hypercholesterolemia (FH), an autosomal dominant inherited disorder resulting in increased levels of circulating plasma low-density lipoprotein (LDL), tendon xanthomas and premature coronary artery disease (CAD), is caused by defects in the LDL receptor gene (LDLR). Three widespread LDLR alterations not causing FH (c.1061-8T>C, c.2177C>T and c.829G>A) and one mutation (c.12G>A) with narrow geographical distribution and thought to cause disease were investigated. In an attempt to improve knowledge on their origin, spread and possible selective effects, estimations of the ages of these variants (t generations) and haplotype analysis were performed by genotyping 86 healthy individuals and 98 FH patients in Spain for five LDLR SNPs: c.81T>C, c.1413G>A, c.1725C>T, c.1959T>C, and c.2232G>A; most patients carried two of these LDLR variants simultaneously. It was found that both the c.1061-8T>C (t = 54) and c.2177C>T alterations (t = 62) arose at about the same time (54 and 62 generations ago, respectively) in the CGCTG haplotype, while the c.12G>A mutation (t = 70) appeared in a CGCCG haplotype carrying an earlier c.829G>A alteration (t = 83). The estimated ages of selectively neutral alterations could explain their distribution by migrations. The origin of the c.12G>A mutation could be in the Iberian Peninsula; despite its estimated age, a low selective pressure could explain its conservation in Spain from where it could have spread to China and Mexico, since the sixteenth century through the Spanish/Portuguese colonial expeditions.


Asunto(s)
Evolución Molecular , Haplotipos , Receptores de LDL/genética , Enfermedad Coronaria/genética , Composición Familiar , Humanos , Hiperlipoproteinemia Tipo II/genética , Desequilibrio de Ligamiento , Enfermedades Musculoesqueléticas/genética , Proteínas Mutantes/genética , Mutación/fisiología , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN , España , Tendones/patología , Xantomatosis/genética
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