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1.
Curr Urol Rep ; 25(2): 49-54, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38157157

RESUMO

PURPOSE OF REVIEW: The purpose of this review is to update the information about the different types of reconstruction after partial nephrectomy, with special emphasis on the new methods of suture-free hemostasis currently available. RECENT FINDINGS: The aim of renal reconstruction is to avoid bleeding and leakage of the collecting system, but now the renorrhaphy technique used is considered one of the modifiable determinants of renal function after surgery. In an attempt to avoid the loss of renal function implicit in classic reconstruction, new techniques have been described to control hemostasis and urinary leakage, which employ fewer suture layers, different suture materials and designs, and a wide range of commercially available hemostatic materials. Multiple suture characteristics have been studied as a potential factor influencing the renal function observed after partial nephrectomy. Single-plane suture techniques, the use of bearded sutures, and running sutures seem to be associated with less deterioration in postoperative renal function, and deep medullary sutures should be avoided to avoid affecting the arcuate arteries. Sutureless hemostasis systems could prevent the deterioration of renal function and complications derived from suturing, also reducing ischemia time and surgical time without increasing the risk of complications.


Assuntos
Neoplasias Renais , Laparoscopia , Humanos , Nefrectomia/métodos , Rim/cirurgia , Neoplasias Renais/cirurgia , Perda Sanguínea Cirúrgica/prevenção & controle , Técnicas de Sutura
2.
J Therm Biol ; 121: 103862, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38703597

RESUMO

Elevation gradients provide powerful study systems for examining the influence of environmental filters in shaping species assemblages. High-mountain habitats host specific high-elevation assemblages, often comprising specialist species adapted to endure pronounced abiotic stress, while such harsh conditions prevent lowland species from colonizing or establishing. While thermal tolerance may drive the altitudinal segregation of ectotherms, its role in structuring aquatic insect communities remains poorly explored. This study investigates the role of thermal physiology in shaping the current distribution of high-mountain diving beetles from the Sierra Nevada Iberian mountain range and closely related lowland species. Cold tolerance of five species from each altitudinal zone was measured estimating the supercooling point (SCP), lower lethal temperature (LLT) and tolerance to ice enclosure, while heat tolerance was assessed from the heat coma temperature (HCT). Alpine species exhibited wider fundamental thermal niches than lowland species, likely associated with the broader range of climatic conditions in high-mountain areas. Cold tolerance did not seem to prevent lowland species from colonizing higher elevations, as most studied species were moderately freeze-tolerant. Therefore, fundamental thermal niches seem not to fully explain species segregation along elevation gradients, suggesting that other thermal tolerance traits, environmental factors, and biotic interactions may also play important roles.


Assuntos
Altitude , Termotolerância , Animais , Besouros/fisiologia , Ecossistema , Aclimatação , Temperatura Baixa
3.
Reprod Biomed Online ; 46(3): 536-542, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36567150

RESUMO

RESEARCH QUESTION: Is the DuoStim strategy an effective alternative to two conventional ovarian stimulation cycles in poor-prognosis patients undergoing preimplantation genetic testing for aneuploidies (PGT-A) to improve euploidy rates and obtain the first euploid embryo in less time? DESIGN: This randomized controlled trial was performed at IVI Madrid between June 2017 and December 2020 and included 80 patients with a suboptimal profile aged 38 or older undergoing PGT-A cycles. Patients were blindly randomized into two groups: 39 women underwent two ovarian stimulations in consecutive cycles (control group), whereas the double stimulation strategy was applied to 41 women (DuoStim group). The main outcome was the euploidy rate in each group. The secondary outcomes were the time it took to obtain a euploid embryo and the main cycle outcomes. RESULTS: The baseline characteristics of the patients were similar. No differences were found between the control group and the DuoStim group in the mean days of stimulation (21.3 ± 1.6 versus 23.0 ± 1.4, P = 0.10), total gonadotrophins (4005 ± 450 versus 4245 ± 430, P = 0.43), metaphase II oocytes (8.7 ± 1.8 versus 6.8 ± 1.7, P = 0.15) or euploid embryos obtained (0.8 ± 0.4 versus 0.6 ± 0.4, P = 0.45). The euploid rate per randomized patient (ITT) was 16.1% in the control group versus 22.7% in the DuoStim group, with P-values of 0.371, and the euploidy rate per patient treated was 39.0% versus 45.7% in the control versus DuoStim groups. However, there was a significant difference in the average number of days it took to obtain a euploid blastocyst, favouring the DuoStim group (44.1 ± 2.0 versus 23.3 ± 2.8, P < 0.001). CONCLUSIONS: The use of the DuoStim strategy in poor-prognosis patients undergoing PGT-A cycles maintains a similar euploidy rate while reducing the time required to obtain a euploid blastocyst.


Assuntos
Testes Genéticos , Diagnóstico Pré-Implantação , Feminino , Gravidez , Humanos , Blastocisto/fisiologia , Aneuploidia , Embrião de Mamíferos , Estudos Retrospectivos , Fertilização in vitro
4.
Gynecol Endocrinol ; 39(1): 2205952, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37156263

RESUMO

OBJECTIVE: To determine the incidence and severity of ovarian hyperstimulation syndrome (OHSS) in high responders (25-35 follicles with a diameter of ≥12 mm on day of triggering) who received a gonadotropin-releasing hormone (GnRH) agonist to trigger final follicular maturation. METHODS: We used individual data from women who participated in four different clinical trials and were high responders to ovarian stimulation in a GnRH antagonist protocol in this retrospective combined analysis. All women were evaluated for signs and symptoms of OHSS using identical criteria based on Golan's system (1989). RESULTS: High responders (n = 77) were of different ethnicities. There were no differences in baseline characteristics between women with or without signs and symptoms of OHSS. Mean ± standard deviation baseline data were: age, 32.3 ± 3.5 years; anti-Müllerian hormone, 42.4 ± 20.7 pmol/L; antral follicle count, 21.5 ± 9.2. Before triggering, duration of stimulation was 9.5 ± 1.6 days and the mean number of follicles with a diameter of ≥12 mm and ≥17 mm was 26.5 ± 4.4 and 8.8 ± 4.7, respectively. Mean serum estradiol (17,159 pmol/l) and progesterone (5.1 nmol/l) levels were high at 36 h after triggering. Overall, 17/77 high responders (22%) developed signs and symptoms of mild OHSS which lasted 6-21 days. The most frequently prescribed medication was cabergoline to prevent worsening of OHSS. No severe OHSS occurred and no OHSS cases were reported as serious adverse events. CONCLUSIONS: High responders receiving GnRH agonist for triggering should be informed that they may experience signs and symptoms of mild OHSS.


Assuntos
Síndrome de Hiperestimulação Ovariana , Feminino , Humanos , Adulto , Gravidez , Síndrome de Hiperestimulação Ovariana/epidemiologia , Síndrome de Hiperestimulação Ovariana/prevenção & controle , Síndrome de Hiperestimulação Ovariana/etiologia , Incidência , Estudos Retrospectivos , Gonadotropina Coriônica/uso terapêutico , Indução da Ovulação/efeitos adversos , Indução da Ovulação/métodos , Hormônio Liberador de Gonadotropina , Fertilização in vitro/métodos , Taxa de Gravidez
5.
J Assist Reprod Genet ; 40(5): 1071-1081, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36933094

RESUMO

PURPOSE: To provide an agreed upon definition of hyper-response for women undergoing ovarian stimulation (OS)? METHODS: A literature search was performed regarding hyper-response to ovarian stimulation for assisted reproductive technology. A scientific committee consisting of 5 experts discussed, amended, and selected the final statements in the questionnaire for the first round of the Delphi consensus. The questionnaire was distributed to 31 experts, 22 of whom responded (with representation selected for global coverage), each anonymous to the others. A priori, it was decided that consensus would be reached when ≥ 66% of the participants agreed and ≤ 3 rounds would be used to obtain this consensus. RESULTS: 17/18 statements reached consensus. The most relevant are summarized here. (I) Definition of a hyper-response: Collection of ≥ 15 oocytes is characterized as a hyper-response (72.7% agreement). OHSS is not relevant for the definition of hyper-response if the number of collected oocytes is above a threshold (≥ 15) (77.3% agreement). The most important factor in defining a hyper-response during stimulation is the number of follicles ≥ 10 mm in mean diameter (86.4% agreement). (II) Risk factors for hyper-response: AMH values (95.5% agreement), AFC (95.5% agreement), patient's age (77.3% agreement) but not ovarian volume (72.7% agreement). In a patient without previous ovarian stimulation, the most important risk factor for a hyper-response is the antral follicular count (AFC) (68.2% agreement). In a patient without previous ovarian stimulation, when AMH and AFC are discordant, one suggesting a hyper-response and the other not, AFC is the more reliable marker (68.2% agreement). The lowest serum AMH value that would place one at risk for a hyper-response is ≥ 2 ng/ml (14.3 pmol/L) (72.7% agreement). The lowest AFC that would place one at risk for a hyper-response is ≥ 18 (81.8% agreement). Women with polycystic ovarian syndrome (PCOS) as per Rotterdam criteria are at a higher risk of hyper-response than women without PCOS with equivalent follicle counts and gonadotropin doses during ovarian stimulation for IVF (86.4% agreement). No consensus was reached regarding the number of growing follicles ≥ 10 mm that would define a hyper-response. CONCLUSION: The definition of hyper-response and its risk factors can be useful for harmonizing research, improving understanding of the subject, and tailoring patient care.


Assuntos
Hormônio Foliculoestimulante , Síndrome do Ovário Policístico , Humanos , Feminino , Técnica Delphi , Fertilização in vitro , Indução da Ovulação , Medição de Risco , Fertilização , Hormônio Antimülleriano
6.
J Assist Reprod Genet ; 40(11): 2681-2695, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37713144

RESUMO

PURPOSE: To provide agreed-upon guidelines on the management of a hyper-responsive patient undergoing ovarian stimulation (OS) METHODS: A literature search was performed regarding the management of hyper-response to OS for assisted reproductive technology. A scientific committee consisting of 4 experts discussed, amended, and selected the final statements. A priori, it was decided that consensus would be reached when ≥66% of the participants agreed, and ≤3 rounds would be used to obtain this consensus. A total of 28/31 experts responded (selected for global coverage), anonymous to each other. RESULTS: A total of 26/28 statements reached consensus. The most relevant are summarized here. The target number of oocytes to be collected in a stimulation cycle for IVF in an anticipated hyper-responder is 15-19 (89.3% consensus). For a potential hyper-responder, it is preferable to achieve a hyper-response and freeze all than aim for a fresh transfer (71.4% consensus). GnRH agonists should be avoided for pituitary suppression in anticipated hyper-responders performing IVF (96.4% consensus). The preferred starting dose in the first IVF stimulation cycle of an anticipated hyper-responder of average weight is 150 IU/day (82.1% consensus). ICoasting in order to decrease the risk of OHSS should not be used (89.7% consensus). Metformin should be added before/during ovarian stimulation to anticipated hyper-responders only if the patient has PCOS and is insulin resistant (82.1% consensus). In the case of a hyper-response, a dopaminergic agent should be used only if hCG will be used as a trigger (including dual/double trigger) with or without a fresh transfer (67.9% consensus). After using a GnRH agonist trigger due to a perceived risk of OHSS, luteal phase rescue with hCG and an attempt of a fresh transfer is discouraged regardless of the number of oocytes collected (72.4% consensus). The choice of the FET protocol is not influenced by the fact that the patient is a hyper-responder (82.8% consensus). In the cases of freeze all due to OHSS risk, a FET cycle can be performed in the immediate first menstrual cycle (92.9% consensus). CONCLUSION: These guidelines for the management of hyper-response can be useful for tailoring patient care and for harmonizing future research.


Assuntos
Síndrome de Hiperestimulação Ovariana , Feminino , Humanos , Gravidez , Consenso , Técnica Delphi , Hormônio Liberador de Gonadotropina , Gonadotropina Coriônica , Fertilização in vitro/métodos , Indução da Ovulação/métodos , Medição de Risco , Taxa de Gravidez
7.
Hum Reprod ; 37(2): 284-296, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-34875061

RESUMO

STUDY QUESTION: What are the key considerations for developing an enhanced transcriptomic method for secretory endometrial tissue dating? SUMMARY ANSWER: Multiple gene expression signature combinations can serve as biomarkers for endometrial dating, but their predictive performance is variable and depends on the number and identity of the genes included in the prediction model, the dataset characteristics and the technology employed for measuring gene expression. WHAT IS KNOWN ALREADY: Among the new generation of transcriptomic endometrial dating (TED) tools developed in the last decade, there exists variation in the technology used for measuring gene expression, the gene makeup and the prediction model design. A detailed study, comparing prediction performance across signatures for understanding signature behaviour and discrepancies in gene content between them, is lacking. STUDY DESIGN, SIZE, DURATION: A multicentre prospective study was performed between July 2018 and October 2020 at five different centres from the same group of clinics (Spain). This study recruited 281 patients and finally included in the gene expression analysis 225 Caucasian patients who underwent IVF treatment. After preprocessing and batch effect filtering, gene expression measurements from 217 patients were combined with artificial intelligence algorithms (support vector machine, random forest and k-nearest neighbours) allowing evaluation of different prediction models. In addition, secretory-phase endometrial transcriptomes from gene expression omnibus (GEO) datasets were analysed for 137 women, to study the endometrial dating capacity of genes independently and grouped by signatures. This provided data on the consistency of prediction across different gene expression technologies and datasets. PARTICIPANTS/MATERIALS, SETTING, METHODS: Endometrial biopsies were analysed using a targeted TruSeq (Illumina) custom RNA expression panel called the endometrial dating panel (ED panel). This panel included 301 genes previously considered relevant for endometrial dating as well as new genes selected for their anticipated value in detecting the secretory phase. Final samples (n = 217) were divided into a training set for signature discovery and an independent testing set for evaluation of predictive performance of the new signature. In addition, secretory-phase endometrial transcriptomes from GEO were analysed for 137 women to study endometrial dating capacity of genes independently and grouped by signatures. Predictive performance among these signatures was compared according to signature gene set size. MAIN RESULTS AND THE ROLE OF CHANCE: Testing of the ED panel allowed development of a model based on a new signature of 73 genes, which we termed 'TED' and delivers an enhanced tool for the consistent dating of the secretory phase progression, especially during the mid-secretory endometrium (3-8 days after progesterone (P) administration (P + 3-P + 8) in a hormone replacement therapy cycle). This new model showed the best predictive capacity in an independent test set for staging the endometrial tissue in the secretory phase, especially in the expected window of implantation (average of 114.5 ± 7.2 h of progesterone administered; range in our patient population of 82-172 h). Published sets of genes, in current use for endometrial dating and the new TED genes, were evaluated in parallel in whole-transcriptome datasets and in the ED panel dataset. TED signature performance was consistently excellent for all datasets assessed, frequently outperforming previously published sets of genes with a smaller number of genes for dating the endometrium in the secretory phase. Thus, this optimized set exhibited prediction consistency across datasets. LARGE SCALE DATA: The data used in this study is partially available at GEO database. GEO identifiers GSE4888, GSE29981, GSE58144, GSE98386. LIMITATIONS, REASONS FOR CAUTION: Although dating the endometrial biopsy is crucial for investigating endometrial progression and the receptivity process, further studies are needed to confirm whether or not endometrial dating methods in general are clinically useful and to guide the specific use of TED in the clinical setting. WIDER IMPLICATIONS OF THE FINDINGS: Multiple gene signature combinations provide adequate endometrial dating, but their predictive performance depends on the identity of the genes included, the gene expression platform, the algorithms used and dataset characteristics. TED is a next-generation endometrial assessment tool based on gene expression for accurate endometrial progression dating especially during the mid-secretory. STUDY FUNDING/COMPETING INTEREST(S): Research funded by IVI Foundation (1810-FIVI-066-PD). P.D.-G. visiting scientist fellowship at Oxford University (BEFPI/2010/032) and Josefa Maria Sanchez-Reyes' predoctoral fellowship (ACIF/2018/072) were supported by a program from the Generalitat Valenciana funded by the Spanish government. A.D.-P. is supported by the FPU/15/01398 predoctoral fellowship from the Ministry of Science, Innovation and Universities (Spanish Government). D.W. received support from the NIHR Oxford Biomedical Research Centre. The authors do not have any competing interests to declare.


Assuntos
Progesterona , Transcriptoma , Inteligência Artificial , Endométrio/metabolismo , Feminino , Humanos , Masculino , Progesterona/metabolismo , Estudos Prospectivos
8.
Reproduction ; 164(5): 259-267, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36136831

RESUMO

In brief: COVID-19 does not affect the telomeres or fertility outcomes in mild cases. However, in women with severe symptoms, telomeres of granulosa cells are shorter, and the oocyte maturation rate is decreased. Abstract: The coronavirus SARS-CoV-2 causes COVID-19 disease and affects primarily the lungs and also other organs, causing accelerated cell aging. One of the main pathways involved in aging is telomere attrition, which ultimately leads to defective tissue regeneration and organ dysfunction. Indeed, short telomeres in aged people aggravate the COVID-19 symptoms, and COVID-19 survivors showed shorter telomeres in blood cells. The SARS-CoV-2 has been detected in testis, but the ovaries, which express the viral entry factors, have not been fully explored. Our objective was to analyze telomeres and reproductive outcomes in women who had COVID-19 and controls. In this prospective cohort study, granulosa cells (GCs) and blood were collected from 65 women. Telomere length (TL) was measured by high-throughput in situ hybridization. Mean TL of GCs and peripheral blood mononuclear cells (PBMCs) was alike in control and mild cases. However, mean TL of GCs was lower in severe cases compared to controls (P = 0.017). Control and COVID groups had similar ovarian reserve and number of total oocytes after puncture. However, the oocyte maturation rate was lower in severe cases (P = 0.018). Interestingly, a positive correlation between the oocyte maturation rate and TL of GCs was found in the control group (P = 0.024). Our findings point to a potential impact of the coronavirus infection on telomeres and reproductive outcomes in severe cases. This might be considered upon possible new SARS-CoV threats, to favor treatments that enhance oocyte maturation in women severely affected by coronavirus undergoing ART.


Assuntos
COVID-19 , Feminino , Humanos , Leucócitos Mononucleares , Masculino , Oócitos , Estudos Prospectivos , SARS-CoV-2 , Telômero
9.
Clin Invest Ginecol Obstet ; 49(1): 100704, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-34230736

RESUMO

BACKGROUND: Work-related stress, fear of becoming infected, and the lack of means to combat the COVID-19 pandemic, added to the situation of lockdown at home could lead to a strong impact on mental health.The objective was to determine the level of anxiety through the State-Trait Anxiety Inventory, STAI completed by the professionals of a delivery room who treated COVID-19-positive pregnant women. MATERIAL AND METHODS: Descriptive cross-sectional study in an obstetric area in Barcelona from March 14th to May 24th, 2020. Study population: healthcare staff over 18 years old, without diagnosed anxiety disorders prior to the pandemic.The main parameters to study were the level of «state anxiety¼ and «trait anxiety¼ according to the STAI questionnaire.Descriptive and inferential statistics were performed. The level of statistical significance used was p<.05. RESULTS: Seventy-seven professionals participated in this study.The mean score for «state anxiety¼ was 26.3 points (p-value = .067) and for «strait anxiety¼, 14.3 points (p-value = .091).It was observed that the professionals who had children (p-value = .048) and the professionals who stated that their family economic income had decreased (p-value = .026) showed higher average scores of «state anxiety¼. A positive association was observed between years of working experience and the level of «state anxiety¼, observing statistically significant differences, p-value = .030. CONCLUSIONS: The professionals who had suffered a reduction in their income together with those who lived with children presented higher scores of «state anxiety¼.

10.
Tech Coloproctol ; 25(8): 965-969, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33999293

RESUMO

BACKGROUND: The aim of this study was to investigate the effectiveness of devices manufactured with 3D printing for performing transanal endoscopic procedures without pneumorectum. METHODS: Functional devices were designed in the Polytechnic School of Engineering of Gijón from 2016 to 2018 using three-dimensional (3D) solid modelling software (Solid-Works®), that allows customization of the device (diameter and length). The devices were made in acrylonitrile butadiene styrene (ABS) by additive manufacturing using an HP Designjet 3D Printer, with fused deposition modelling (FDM) technology. Tests were carried out on mixed simulators (with viscera) and cadavers with a prototype in the form of an open cylindrical base ellipsoid spindle with two bars. In this paper, we present the information of the first series of patients in which this device has been used to perform a full-thikness endoscopic resection of the rectal wall without pneumorectum. The characteristics of the patients, size, and location of the lesion, the type of anesthesia used, the duration of the procedure, hospital stay, complications, and pathology were analyzed. An endoscopic follow-up was also carried out for at least 2 years. RESULTS: Seven interventions were carried out in six patients. The lesions were located at a mean distance of 5 cm from the anal verge and an average area of 11.8 cm2. Four of the procedures were performed with general anesthesia and 3 with spinal anesthesia. Histopathology examination identified 3 adenomas, 3 pT1 and 1 pT2 adenocarcinomas. All excisions were full thickness. En bloc excision was possible in all cases. In only one case of a benign polyp there was a positive lateral margin. As regards complications, there was one case of postoperative rectal bleeding without the need for transfusions. There were no readmissions and no postoperative mortality. CONCLUSIONS: An innovative device made with a 3D printer can be used successfully in transanal endoscopic resections of the rectal wall, with spinal anaesthesia and avoiding the need for pneumorectum.


Assuntos
Neoplasias Retais , Cirurgia Endoscópica Transanal , Humanos , Impressão Tridimensional , Reto , Resultado do Tratamento
11.
J Assist Reprod Genet ; 37(9): 2081-2092, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32578032

RESUMO

PURPOSE: Intracytroplasmatic sperm injection (ICSI) is a common procedure used to improve reproductive results, even among couples without male factor infertility. However, the evidence available is still uncertain on the possible advantages and deficiencies that this procedure may have in patients with no formal indication for ICSI. METHODS: A SWOT (strengths, weaknesses, opportunities, threats) analysis examines the possible advantages and deficiencies of performing ICSI in these patients with no formal indication. RESULTS: The evidence suggests that ICSI is not justified for non-male factor infertile couples requiring in vitro conception. One of the major strengths associated to the procedure is the virtual elimination of cases further complicated by total fertilization failure and a combination between IVF and ICSI on sibling oocytes has been advised in the literature. Greater technical difficulties, higher costs and performing an unnecessary invasive technique in some cases represent some of the weaknesses of the procedure, and questions regarding safety issues should not be ruled out. CONCLUSION: Despite the widespread use of ICSI in patients without a formal diagnosis of male factor infertility, evidence demonstrating its effectiveness in this population is still lacking. Additional large and well-designed randomized controlled trials are needed to clarify definitive indications for ICSI in non-male factor infertility.


Assuntos
Fertilização in vitro/tendências , Infertilidade Masculina/genética , Injeções de Esperma Intracitoplásmicas/tendências , Espermatozoides/crescimento & desenvolvimento , Adulto , Transferência Embrionária , Feminino , Humanos , Infertilidade Masculina/terapia , Masculino , Oócitos/citologia , Oócitos/crescimento & desenvolvimento , Gravidez , Taxa de Gravidez , Sêmen/metabolismo
12.
J Theor Biol ; 462: 446-454, 2019 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-30502407

RESUMO

The aim of this work is to study the aging rate at which human follicles reach the preovulatory state. To this end, both telomere length and telomerase activity effects on granulosa cells (GCs) aging has been studied. GCs are somatic cells which determine the development of the oocyte. A human preantral follicle takes approximately 85 days to achieve the preovulatory size, going through several stages (Gougeon, 1996). The telomere length of GCs of each class of follicles, during folliculogenesis, are modelled using a chemical master equation formalism similar to the one in Wesch et al. (2016). Seven differential ordinary systems of equations, corresponding to seven stages of the follicule maturation, concatenated in time, are considered. The mitotic and death rates are approximated by using the mean number of GCs in each class of follicles and the time they remain on each stage. The influence of different telomerase activity rates and the telomere shortening of the preovulatory follicle is studied. Some cases of infertility are associated with low levels of telomerase activity and short telomeres in GCs. The method aims at understanding how low levels of telomerase activity in preovulatory stages lead to the accumulation of aged GCs. In the case of higher telomerase activities, the mathematical model predicts a more juvenile outcome in preovulatory follicles. Juvenile GCs, could be critical for embryo development if the oocyte were fertilized, since GCs, transformed in corpus luteum, must divide and increase their size (Alila and Hansel, 1984) to sustain early pregnancy (Csapo et al., 1972).


Assuntos
Envelhecimento , Modelos Teóricos , Folículo Ovariano/fisiologia , Telomerase/metabolismo , Desenvolvimento Embrionário , Feminino , Fertilidade , Células da Granulosa/ultraestrutura , Humanos , Telômero/ultraestrutura
13.
Eur J Neurol ; 26(9): 1200-1204, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30977955

RESUMO

BACKGROUND AND PURPOSE: Neurofilament light chain is a cytoskeletal protein of neurons. Its levels are increasingly recognized as measures of neuroaxonal damage. The aim of this study was to explore serum neurofilament light chain (sNfL) levels in multiple sclerosis (MS) patients and healthy controls during pregnancy and puerperium. METHODS: This was a prospective, longitudinal, single-center study. sNfL concentration was assessed using a highly sensitive single-molecule array during pregnancy and in puerperium, in a cohort of 39 pregnant patients with relapsing multiple sclerosis (P-MS). Twenty-one healthy pregnant women (HPW) served as a control group. Eight P-MS suffered relapses during pregnancy (P-MS-R) in the first or second trimesters. RESULTS: No differences in pregnancy and delivery data were observed between P-MS and HPW. P-MS showed higher sNfL values than HPW in the first trimester, independently of the presence (P = 0.002) or not (P = 0.02) of relapses during pregnancy. However, in the third trimester, only P-MS-R showed higher sNfL values than HPW (P = 0.001). These differences extended to the puerperium, where P-MS-R showed higher sNfL values than those with no relapses during gestation (P = 0.02). CONCLUSION: These data strongly suggest that sNfL levels reflect MS activity during pregnancy. Additionally, the absence of relapses during pregnancy may have a beneficial effect on neurodegeneration during puerperium.


Assuntos
Esclerose Múltipla/sangue , Proteínas de Neurofilamentos/sangue , Complicações na Gravidez/sangue , Adulto , Biomarcadores/sangue , Feminino , Humanos , Estudos Longitudinais , Gravidez
15.
Hum Reprod ; 33(12): 2222-2231, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30383235

RESUMO

STUDY QUESTION: Is the indication for fertility preservation (FP) related to success in IVF cycles after elective-FP (EFP) for age-related fertility decline and FP before cancer treatment (Onco-FP)? SUMMARY ANSWER: Although success rates were lower in cancer patients, there was no statistically significant association between malignant disease and reproductive outcome after correction for age and controlled-ovarian stimulation (COS) regime. WHAT IS KNOWN ALREADY: FP is increasingly applied in assisted reproduction, but little is known about the outcome of IVF cycles with vitrified oocytes in FP patients. STUDY DESIGN, SIZE, DURATION: Retrospective, observational multicenter study of vitrification cycles for FP and of the warming cycles of women who returned to attempt pregnancy from January 2007 to May 2018. PARTICIPANTS/MATERIALS, SETTING, METHODS: In all, 6362 women (EFP = 5289 patients; 7044 cycles + Onco-FP = 1073 patients; 1172 cycles) had their oocytes vitrified for FP. A logistic regression analysis was performed to examine the impact of indication for FP corrected for age at vitrification. The protocol used for COS was also included as a possible confounder. The main outcome measures were oocyte survival and live birth. A detailed description of the baseline and clinical data is provided, with comparisons between EFP and Onco-FP. The cumulative live birth rate (CLBR) per utilized oocyte according to age at vitrification was analyzed in those patients returning to use their oocytes. MAIN RESULTS AND ROLE OF CHANCE: Age at vitrification was significantly older in EFP patients (37.2 ± 4.9 vs. 32.3 ± 3.5 year; P < 0.0001). Fewer oocytes were retrieved and vitrified per cycle in EFP (9.6 ± 8.4 vs. 11.4 ± 3.5 and 7.3 ± 11.3 vs. 8.7 ± 2.1, respectively; P < 0.05), but numbers became comparable when analyzed per patient (12.8 ± 7.4 vs. 12.5 ± 3.2 and 9.8 ± 6.4 vs. 9.5 ± 2.6). Storage time was shorter in EFP (2.1 ± 1.6 vs. 4.1 ± 0.9 years; P < 0.0001). In all, 641 (12.1%) EFP and 80 (7.4%) Onco-FP patients returned to attempt pregnancy (P < 0.05). Overall oocyte survival was comparable (83.9% vs. 81.8%; NS), but lower for onco-FP patients among younger (≤35 year) subjects (81.2% vs. 91.4%; P > 0.05). Fewer EFP cycles finished in embryo transfer (50.2% vs. 72.5%) (P < 0.05). The implantation rate was 42.6% and 32.5% in EFP versus Onco-FP (P < 0.05). Ongoing pregnancy (57.7% vs. 35.7%) and live birth rates (68.8% vs. 41.1%) were higher in EFP patients aged ≤35 than the Onco-FP matching age patients (P < 0.05). The reason for FP per se had no effect on oocyte survival (OR = 1.484 [95%CI = 0.876-2.252]; P = 0.202) or the CLBR (OR = 1.275 [95%CI = 0.711-2.284]; P = 0.414). Conversely, age (<36 vs. ≥36 y) impacted oocyte survival (adj.OR = 1.922 [95%CI = 1.274-2.900]; P = 0.025) and the CLBR (adj.OR= 3.106 [95%CI = 2.039-4.733]; P < 0.0001). The Kaplan-Meier analysis showed a significantly higher cumulative probability of live birth in patients <36 versus >36 in EFP (P < 0.0001), with improved outcomes when more oocytes were available for IVF. LIMITATIONS, REASONS FOR CAUTION: Statistical power to compare IVF outcomes is limited by the few women who came to use their oocytes in the Onco-FP group. The patients' ages and the COS protocols used were significantly different between the EFP and ONCO-PP groups. WIDER IMPLICATIONS OF THE FINDINGS: Although the implantation rate was significantly lower in the Onco-FP patients the impact of cancer disease per se was not proven'. EFP patients should be counseled according to their age and number of available oocytes. STUDY FUNDING/COMPETING INTEREST(S): No external funding was used for this study. The authors have no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Preservação da Fertilidade/métodos , Fertilização in vitro , Neoplasias , Adulto , Criopreservação , Feminino , Humanos , Recuperação de Oócitos , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Vitrificação
16.
Reprod Biomed Online ; 37(6): 709-715, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30527061

RESUMO

Hysteroscopic septum resection in women with unfavourable reproductive and clinical outcomes has become common practice worldwide to improve reproductive results. No clear evidence on the possible advantages and drawbacks of this procedure has been published. In this opinion paper, based on a SWOT (strengths, weaknesses, opportunities, threats) analysis, the different aspects of this strategy are evaluated. Currently, no level 1 published evidence supports uterine resection in women with septate uterus. Clinical evidence from the studies analysed matches the more recent guidelines and suggests an improvement in reproductive outcomes after hysteroscopic resection of the septum, particularly in infertile women and women who have experienced recurrent miscarriages. In a patient with no history of infertility or prior pregnancy loss, it may be reasonable to consider septum incision after counselling about the potential risks and benefits of the procedure. Published clinical data in favour of the intervention, however, are based on studies with important methodological limitations. In this situation, the clinician and patient should reach an agreement together, based on the pros and cons of this intervention. Well-designed randomized controlled trials are required to confirm the clinical benefits and cost-effectiveness of this procedure.


Assuntos
Procedimentos Cirúrgicos em Ginecologia/estatística & dados numéricos , Infertilidade Feminina/cirurgia , Útero/cirurgia , Aborto Habitual , Aborto Induzido , Adulto , Feminino , Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Humanos , Histeroscopia , Guias de Prática Clínica como Assunto , Reprodução , Medicina Reprodutiva , Resultado do Tratamento , Útero/anormalidades
17.
Phys Rev Lett ; 118(18): 185002, 2017 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-28524687

RESUMO

Measurements of the relaxation of a zonal electrostatic potential perturbation in a nonaxisymmetric magnetically confined plasma are presented. A sudden perturbation of the plasma equilibrium is induced by the injection of a cryogenic hydrogen pellet in the TJ-II stellarator, which is observed to be followed by a damped oscillation in the electrostatic potential. The waveform of the relaxation is consistent with theoretical calculations of zonal potential relaxation in a nonaxisymmetric magnetic geometry. The turbulent transport properties of a magnetic confinement configuration are expected to depend on the features of the collisionless damping of zonal flows, of which the present Letter is the first direct observation.

19.
Nano Lett ; 16(1): 227-31, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26636471

RESUMO

Using transport measurements, we investigate multicomponent quantum Hall (QH) ferromagnetism in dual-gated rhombohedral trilayer graphene (r-TLG) in which the real spin, orbital pseudospin, and layer pseudospins of the lowest Landau level form spontaneous ordering. We observe intermediate QH plateaus, indicating a complete lifting of the degeneracy of the zeroth Landau level (LL) in the hole-doped regime. In charge neutral r-TLG, the orbital degeneracy is broken first, and the layer degeneracy is broken last and only in the presence of an interlayer potential U⊥. In the phase space of U⊥ and filling factor ν, we observe an intriguing "hexagon" pattern, which is accounted for by a model based on crossings between symmetry-broken LLs.

20.
Rev Gastroenterol Mex ; 82(4): 309-327, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28413079

RESUMO

Since the publication of the 2007 dyspepsia guidelines of the Asociación Mexicana de Gastroenterología, there have been significant advances in the knowledge of this disease. A systematic search of the literature in PubMed (01/2007 to 06/2016) was carried out to review and update the 2007 guidelines and to provide new evidence-based recommendations. All high-quality articles in Spanish and English were included. Statements were formulated and voted upon using the Delphi method. The level of evidence and strength of recommendation of each statement were established according to the GRADE system. Thirty-one statements were formulated, voted upon, and graded. New definition, classification, epidemiology, and pathophysiology data were provided and include the following information: Endoscopy should be carried out in cases of uninvestigated dyspepsia when there are alarm symptoms or no response to treatment. Gastric and duodenal biopsies can confirm Helicobacter pylori infection and rule out celiac disease, respectively. Establishing a strong doctor-patient relationship, as well as dietary and lifestyle changes, are useful initial measures. H2-blockers, proton-pump inhibitors, prokinetics, and antidepressants are effective pharmacologic therapies. H.pylori eradication may be effective in a subgroup of patients. There is no evidence that complementary and alternative therapies are beneficial, with the exception of Iberogast and rikkunshito, nor is there evidence on the usefulness of prebiotics, probiotics, or psychologic therapies. The new consensus statements on dyspepsia provide guidelines based on up-to-date evidence. A discussion, level of evidence, and strength of recommendation are presented for each statement.


Assuntos
Dispepsia/diagnóstico , Dispepsia/terapia , Dispepsia/epidemiologia , Dispepsia/etiologia , Endoscopia Gastrointestinal , Infecções por Helicobacter/complicações , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/terapia , Helicobacter pylori , Humanos , México/epidemiologia
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