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1.
Hum Reprod ; 38(9): 1733-1745, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381072

RESUMO

STUDY QUESTION: Should we perform oocyte accumulation to preserve fertility in women with Turner syndrome (TS)? SUMMARY ANSWER: The oocyte cryopreservation strategy is not well adapted for all TS women as their combination of high basal FSH with low basal AMH and low percentage of 46,XX cells in the karyotype significantly reduces the chances of freezing sufficient mature oocytes for fertility preservation. WHAT IS KNOWN ALREADY: An oocyte cryopreservation strategy requiring numerous stimulation cycles is needed to preserve fertility in TS women, to compensate for the low ovarian response, the possible oocyte genetic alterations, the reduced endometrial receptivity, and the increased rate of miscarriage, observed in this specific population. The validation of reliable predictive biomarkers of ovarian response to hormonal stimulation in TS patients is necessary to help practitioners and patients choose the best-personalized fertility preservation strategy. STUDY DESIGN, SIZE, DURATION: A retrospective bicentric study was performed from 1 January 2011 to 1 January 2023. Clinical and biological data from all TS women who have received from ovarian stimulation for fertility preservation were collected. A systematic review of the current literature on oocyte retrieval outcomes after ovarian stimulation in TS women was also performed (PROSPERO registration number: CRD42022362352). PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 14 TS women who had undergone ovarian stimulation for fertility preservation were included, representing the largest cohort of TS patients published to date (n = 14 patients, 24 cycles). The systematic review of the literature identified 34 additional TS patients with 47 oocyte retrieval outcomes after ovarian stimulation in 14 publications (n = 48 patients, n = 71 cycles in total). MAIN RESULTS AND THE ROLE OF CHANCE: The number of cryopreserved mature oocytes on the first cycle for TS patients was low (4.0 ± 3.7). Oocyte accumulation was systematically proposed to increase fertility potential and was accepted by 50% (7/14) of patients (2.4 ± 0.5 cycles), leading to an improved total number of 10.9 ± 7.2 cryopreserved mature oocytes per patient. In the group who refused the oocyte accumulation strategy, only one patient exceeded the threshold of 10 mature cryopreserved oocytes. In contrast, 57.1% (4/7) and 42.9% (3/7) of patients who have underwent the oocyte accumulation strategy reached the threshold of 10 and 15 mature cryopreserved oocytes, respectively (OR = 8 (0.6; 107.0), P = 0.12; OR= 11 (0.5; 282.1), P = 0.13). By analyzing all the data published to date and combining it with our data (n = 48 patients, n = 71 cycles), low basal FSH and high AMH concentrations as well as a higher percentage of 46,XX cells in the karyotype were significantly associated with a higher number of cryopreserved oocytes after the first cycle. Moreover, the combination of low basal FSH concentration (<5.9 IU/l), high AMH concentration (>1.13 ng/ml), and the presence of 46,XX cells (>1%) was significantly predictive of obtaining at least six cryopreserved oocytes in the first cycle, representing objective criteria for identifying patients with real chances of preserving an adequate fertility potential by oocyte cryopreservation. LIMITATIONS, REASONS FOR CAUTION: Our results should be analyzed with caution, as the optimal oocyte number needed for successful live birth in TS patients is still unknown due to the low number of reports their oocyte use in the literature to date. WIDER IMPLICATIONS OF THE FINDINGS: TS patients should benefit from relevant clinical evaluation, genetic counseling and psychological support to make an informed choice regarding their fertility preservation technique, as numerous stimulation cycles would be necessary to preserve a high number of oocytes. STUDY FUNDING/COMPETING INTEREST(S): This research received no external funding. The authors declare no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Preservação da Fertilidade , Síndrome de Turner , Humanos , Feminino , Síndrome de Turner/complicações , Síndrome de Turner/terapia , Estudos Retrospectivos , Preservação da Fertilidade/métodos , Oócitos , Criopreservação/métodos , Hormônio Foliculoestimulante , Indução da Ovulação/métodos , Estudos Multicêntricos como Assunto
2.
Prehosp Emerg Care ; 27(5): 695-703, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35543652

RESUMO

OBJECTIVES: Early airway management during cardiopulmonary resuscitation (CPR) prevents aspiration of gastric contents. Endotracheal intubation is the gold standard to protect airways, but supraglottic airway devices (SGA) may provide some protection with less training. Bag-mask ventilation (BMV) is the most common method used by rescuers. We hypothesized that SGA use by first rescuers during CPR could increase ventilation success rate and also decrease intragastric pressure and pulmonary aspiration. METHODS: We performed a randomized cross-over experimental trial on human cadavers. Protocol A: we assessed the rate of successful ventilation (chest rise), intragastric pressure, and CPR key time metrics. Protocol B: cadaver stomachs were randomized to be filled with 300 mL of either blue or green serum saline solution through a Foley catheter. Each rescuer was randomly assigned to use SGA or BMV during a 5-minute standard CPR period. Then, in a crossover design, the stomach was filled with the second color solution and another 5-minute CPR period was performed using the other airway method. Pulmonary aspiration, defined as the presence of colored solution below the vocal cords, was assessed by a blinded operator using bronchoscopy. A generalized linear mixed model was used for statistical analysis. RESULTS: Protocol A: Forty-eight rescuers performed CPR on 11 cadavers. Median ventilation success was higher with SGA than BMV: 75.0% (IQR: 59.8-87.3) vs. 34.7% (IQR: 25.0-50.0), (p = 0.003). Gastric pressure and differential (maximum minus minimum) gastric pressure were lower in the SGA group: 2.21 mmHg (IQR: 1.66; 2.68) vs. 3.02 mmHg (IQR: 2.02; 4.22) (p = 0.02) and 5.70 mmHg (IQR: 4.10; 7.60) vs. 8.05 mmHg (IQR: 5.40; 11.60) (p = 0.05). CPR key times were not different between groups. Protocol B: Ten cadavers were included with 20 CPR periods. Aspiration occurred in 2 (20%) SGA procedures and 5 (50%) BMV procedures (p = 0.44). CONCLUSION: Use of SGA by rescuers improved the ventilation success rate, decreased intragastric pressure, and did not affect key CPR metrics. SGA use by basic life support rescuers appears feasible and efficient.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Humanos , Reanimação Cardiopulmonar/métodos , Estudos Cross-Over , Intubação Intratraqueal/métodos , Cadáver
3.
Gynecol Obstet Fertil Senol ; 49(2): 112-121, 2021 02.
Artigo em Francês | MEDLINE | ID: mdl-33130043

RESUMO

OBJECTIVE: Five to 7% of breast cancers affect women under 40 years old. The survival of these patients has been improved thanks to therapeutic advances, often to the detriment of their fertility. The objective of this study is to evaluate the activity of oncofertility and the future of young women with breast cancer managed at the Montpellier University Hospital. METHODS: This is a retrospective study including women aged from 18 to 43 years-old diagnosed with breast cancer and referred in oncofertility consultation at the Montpellier University Hospital between July 2011 and December 2018. RESULTS: 190 patients were eligible, three refused to participate to the study, hence 187 patients were included. We estimate that only 33% of young breast cancer patients potentially eligible for fertility preservation (FP) benefited from an oncofertility consultation in our region. Of these 187 patients, 58 (31%) underwent ovarian stimulation for oocyte or embryo vitrification. They were significantly younger: 32.9 vs 34.6 years old (P=0.01) and had fewer invaded lymph nodes. A total of 66 cycles were achieved and 11.4 oocytes or 3 embryos were vitrified per patient. The reuse rate was 3.6% with 91% of post cancer pregnancies being spontaneous. CONCLUSION: The oncofertility care network seems effective at the regional level. Enhancing health professionals' awareness and creating a regional register could improve our long-term follow-up.


Assuntos
Neoplasias da Mama , Preservação da Fertilidade , Adolescente , Adulto , Neoplasias da Mama/terapia , Feminino , Hospitais Universitários , Humanos , Gravidez , Estudos Retrospectivos , Vitrificação , Adulto Jovem
4.
Gynecol Obstet Fertil Senol ; 45(2): 95-103, 2017 Feb.
Artigo em Francês | MEDLINE | ID: mdl-28368802

RESUMO

OBJECTIVES: Finding an efficient treatment for poor responders still poses a tremendous challenge for assisted reproductive technology. In 2011, an international consensus has been reached in Bologna on how to standardize the definition of poor ovarian response (POR) in a simple and reproducible manner. This article provides an objective assessment of the different treatment options currently available. METHODS: A search of the database PUBMED was carried out for studies published in English between October 2000 and April 2016. RESULTS: There is no ideal protocol to manage poor responders even though the antagonist protocol seems to have an advantage of clinicians. This is thanks to better patient tolerance and reduced total dose of gonadotrophin as well as shorter time of stimulation. It seems that there is no benefit in increasing the gonadotrophin daily doses over 300IU nor using any specific type of gonadotrophin. Today, there is insufficient evidence to recommend any additional treatment for poor responders. Only dehydroepiandrosterone (DHEA) seems to increase embryonic quality and pregnancy rate, however further exploration and complementary prospective studies are necessary. CONCLUSION: New treatment strategies such as "oocyte banking" or double stimulation during the same cycle, could provide new prospects in poor responders management.


Assuntos
Técnicas de Reprodução Assistida/tendências , Resultado do Tratamento , Protocolos Clínicos , Desidroepiandrosterona/administração & dosagem , Feminino , Gonadotropinas/administração & dosagem , Humanos , Indução da Ovulação/métodos , Gravidez , Taxa de Gravidez
5.
J Gynecol Obstet Biol Reprod (Paris) ; 44(6): 532-40, 2015 Jun.
Artigo em Francês | MEDLINE | ID: mdl-25200347

RESUMO

OBJECTIVE: Female fertility preservation in the context of cancer management is crucial for patient's health care. The aim of this study was to evaluate the oncofertility practice at our university hospital of Montpellier since 2011. PATIENTS AND METHODS: The evaluation of management of young patients referred to Montpellier University Hospital from September 2011 to September 2013 for oncofertility counselling before cancer treatment. RESULTS: Seventy-one patients were referred to a specialized oncofertility center. Forty-two patients (59.1%) were included in the oncofertility program. Twenty-two patients (31%) were proposed for oocyte vitrification after COS protocol, eight patients (11.3%) for ovarian tissue cryoconservation, seven patients (9.9%) for GnRH injections, three patients (4.2%) ovarian transposition and two patients (2.8%) for embryo cryopreservation. Among the 42 indications of fertility preservation, only 18 will have finally taken place. CONCLUSION: Oncofertility counselling for young patients should now be part of the cancer management. It involves multidisciplinary teams. Further information of both oncologists and patients is needed to improve this new approach in the field of cancer treatments.


Assuntos
Gerenciamento Clínico , Preservação da Fertilidade/métodos , Hospitais Universitários/estatística & dados numéricos , Neoplasias/reabilitação , Encaminhamento e Consulta/estatística & dados numéricos , Adulto , Feminino , Preservação da Fertilidade/estatística & dados numéricos , França , Humanos , Avaliação de Programas e Projetos de Saúde , Adulto Jovem
6.
Gynecol Obstet Fertil ; 42(11): 772-8, 2014 Nov.
Artigo em Francês | MEDLINE | ID: mdl-25442824

RESUMO

OBJECTIVE: To evaluate the effect of induced blastocoele shrinkage before vitrification in a closed carrier device. PATIENTS AND METHODS: Prior to vitrification, blastocyst cavity was artificially shrinked by laser pulse or not treated according to a 2:1 randomized procedure. A total of 185 warming cycles from April 2011 to March 2013 have been analyzed. Clinical pregnancy rate and survival rate were compared between the two groups. The mean (±SD) women age was 33.5±5.7 years for both groups. RESULTS: The pregnancy rate in the group with artificial reduction of the cavity was higher ([32/67] 47.7%) than in the control group but not significantly ([43/113] 38%). The survival rate in the artificial shrinkage group was significantly higher compared with the control group : 99% (102/103) and 91.8% (168/183) respectively (P=0.01). DISCUSSION AND CONCLUSION: This study reveals that artificial shrinkage of blastocoelic cavity by laser pulse before vitrification in a closed carrier device improves survival rate after warming.


Assuntos
Blastocisto/fisiologia , Blastocisto/ultraestrutura , Criopreservação/métodos , Adulto , Criopreservação/instrumentação , Transferência Embrionária , Feminino , Fertilização In Vitro/métodos , Temperatura Alta , Humanos , Gravidez , Taxa de Gravidez
7.
Rev. argent. endocrinol. metab ; 51(2): 51-58, jun. 2014. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-750577

RESUMO

Las metástasis a distancia ocurren en el 10 % de los pacientes con carcinoma diferenciado de tiroides (CDT). Las metástasis óseas (MO) son las segundas en frecuencia, luego de las pulmonares. Son causa de morbilidad significativa y su manejo es complejo. Objetivo: Revisar la experiencia en el diagnóstico y tratamiento de pacientes con MO evaluados en 10 centros asistenciales. Material y métodos: Estudio retrospectivo multicéntrico. Criterio de inclusión: presencia de MO en pacientes con CDT, diagnosticada por a) biopsia de la lesión, b) lesión estructural ósea con captación de 131I asociada a Tiroglobulina (Tg) elevada o c) lesión estructural ósea captante de (fluor-deoxi-glucosa) 18FDG en (Tomografía por emisión de positrones) PET-TC y Tg elevada. Se evaluaron datos extraídos de la revisión de historias clínicas. Resultados: Se incluyeron 47 pacientes, 55 % mujeres; edad: mediana 55 años (rango 15-84). La histología fue carcinoma papilar en 55 %, folicular en 32 % y otros tipos en 13 %. El diagnóstico de las MO fue sincrónico en 47 % y metacrónico en 53 %, estas últimas detectadas en promedio a los 72 meses (7-240) luego del diagnóstico inicial. Las MO fueron sintomáticas en 64 %. El síntoma más frecuente fue el dolor (70 %). La localización más frecuente fue la vertebral (36 %), con compromiso de múltiples sitios en el 68% de los casos. Dieciséis pacientes (34 %) tuvieron además persistencia/recurrencia locorregional y 68 % metástasis en otras localizaciones, siendo la más frecuente la pulmonar (90 %). Los niveles de Tg estimulada se obtuvieron en 38 pacientes; fueron > 100 ng/ml en 87 % y <100 ng/ml en 13 %. La calcemia fue normal en todos los casos. Los marcadores de remodelado óseo estuvieron elevados en 9 de 31 pacientes (29 %). Los tratamientos efectuados fueron 131I (78 %), bifosfonatos (64 %), cirugía (53 %), radioterapia externa (55 %) y otras modalidades (23 %). La mediana de seguimiento fue de 24 meses (1-228). La sobrevida fue de 41 %. Un paciente fue considerado sin evidencia de enfermedad. Veintiocho pacientes (59 %) murieron con enfermedad. La causa de muerte se conoció en 27 casos, relacionándose con las MO en 8 casos (30 %). Conclusiones: Las MO se observaron predominantemente en pacientes >45 años, con una distribución similar por sexo. Fueron múltiples a predomino axial, ocasionando morbilidad en la mayoría de los pacientes. Los marcadores de remodelado óseo estuvieron elevados en un tercio de los casos evaluados. Ningún paciente presentó hipercalcemia. El tratamiento incluyó múltiples modalidades, lo que demuestra la importancia del enfoque multidisciplinario en estos pacientes. Aunque las MO se asociaron a enfermedad incurable, la mortalidad se relacionó principalmente con la diseminación en otras localizaciones del CDT. Rev Argent Endocrinol Metab 51:51-58, 2014 Los autores declaran no poseer conflicto de interés.


Distant metastasis is an infrequent event in patients with differentiated thyroid cancer (DTC) and it occurs approximately in 10 % of cases. Bone is the second metastatic site in patients with DTC. The aim of this multicenter retrospective study was to describe the diagnosis and treatment of bone metas­tases (BMs) in patients followed up in ten different hospitals from Argentina. Diagnosis of BMs was made when: a) BM was confirmed by biopsy, b) a structural bone lesion was found following 131I uptake associated with elevated levels of serum thyroglobulin (Tg) or c) a structural bone lesion was demonstrated by 18FDG uptake on PET/CT, also associated with high levels of serum Tg. Demographical, clinical, pathological and outcome data were obtained from hospital charts. We included 47 patients: 55 % were women, with a median age of 55 years old. Histology of DTC was as follows: 55 % had papillary thyroid cancer, 32 % had follicular thyroid cancer and 13 % had other variants. Diagnosis of BMs were synchronous in 47 % of patients (at the same time as DTC diagnosis) and metachro­nous in 53 %, occurring within a mean period of 72 months after initial diagnosis. In 64 % of patients, BMs were symptomatic: pain was referred in 70 % of these cases. In 68 % of cases, there were multiple sites of BMs, with the spine being the most frequent localization (36 %). In 68 % of patients, other distant metastases were observed, mainly in the lungs. Stimulated Tg levels were known in 38 patients at diagnosis: > 100 ng/ml in 87 % and <100ng/ml in 13 %. Serum calcium level was normal in all subjects in whom it was measured (n = 41). In 9 (29 %) of the 31 patients studied, serum bone turnover markers were elevated. At least one modality of treatment was prescribed in 96 % of patients with BMs. Radioiodine was indicated in 78 % of cases, bisphophonates were prescribed in 64 % of patients, while surgery was performed in 53 %. In 55 % of cases, external beam radiotherapy was also indicated and 23 % of individuals received other therapeutic approaches. Median follow-up was 24 months (range 1-228 months). The survival rate at the end of follow-up was 41 %. One patient (3 %) was considered to have no evidence of disease, 28 patients (59 %) died as a consequence of the DTC. The cause of death was known in 27 cases and it was related to BMs in only 8 patients (30 %). In conclusion, BMs were mainly observed in patients >45 years old, with similar gender distribution. BMs were multiple and had mainly an axial skeletal localization, causing high morbidity in most patients. Although bone turnover markers were elevated in one third of cases, no patient had hypercalcemia. Multiple modali­ties of treatment were used in the majority of cases, which indicates the importance of a multidisciplinary approach. Finally, although BMs were associated with incurable disease, mortality was mainly related to the spread of DTC to other sites, and not specifically to BM. Rev Argent Endocrinol Metab 51:51-58, 2014 No financial conflicts of interest exist.

8.
Hum Reprod ; 28(9): 2381-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23832792

RESUMO

STUDY QUESTION: What are the outcomes of French emergency IVF procedures involving embryo freezing for fertility preservation before gonadotoxic treatment? SUMMARY ANSWER: Pregnancy rates after emergency IVF, cryopreservation of embryos, storage, thawing and embryo transfer (embryo transfer), in the specific context of the preservation of female fertility, seem to be similar to those reported for infertile couples undergoing ART. STUDY DESIGN, SIZE, DURATION: A French retrospective multicentre cohort study initiated by the GRECOT network-the French Study Group for Ovarian and Testicular Cryopreservation. We sent an e-mail survey to the 97 French centres performing the assisted reproduction technique in 2011, asking whether the centre performed emergency IVF and requesting information about the patients' characteristics, indications, IVF cycles and laboratory and follow-up data. The response rate was 53.6% (52/97). PARTICIPANTS/MATERIALS, SETTING, METHODS: Fourteen French centres reported that they performed emergency IVF (56 cycles in total) before gonadotoxic treatment, between 1999 and July 2011, in 52 patients. MAIN RESULTS AND THE ROLE OF CHANCE: The patients had a mean age of 28.9 ± 4.3 years, and a median length of relationship of 3 years (1 month-15 years). Emergency IVF was indicated for haematological cancer (42%), brain tumour (23%), sarcoma (3.8%), mesothelioma (n = 1) and bowel cancer (n = 1). Gynaecological problems accounted for 17% of indications. In 7.7% of cases, emergency IVF was performed for autoimmune diseases. Among the 52 patients concerned, 28% (n = 14) had undergone previous courses of chemotherapy before beginning controlled ovarian stimulation (COS). The initiation of gonadotoxic treatment had to be delayed in 34% of the patients (n = 19). In total, 56 cycles were initiated. The mean duration of stimulation was 11.2 ± 2.5 days, with a mean peak estradiol concentration on the day on which ovulation was triggered of 1640 ± 1028 pg/ml. Three cycles were cancelled due to ovarian hyperstimulation syndrome (n = 1), poor response (n = 1) and treatment error (n = 1). A mean of 8.2 ± 4.8 oocytes were retrieved, with 6.1 ± 4.2 mature oocytes and 4.4 ± 3.3 pronuclear-stage embryos per cycle. The mean number of embryos frozen per cycle was 4.2 ± 3.1. During follow-up, three patients died from the consequences of their disease. For the 49 surviving patients, 22.5% of the couples concerned (n = 11) requested embryo replacement. A total of 33 embryos were thawed with a post-thawing survival rate of 76%. Embryo replacement was finally performed for 10 couples with a total of 25 embryos transferred, leading to one biochemical pregnancy, one miscarriage and three live births. Clinical pregnancy rate and live birth per couple who wanted a pregnancy after cancer were, respectively, 36% (95% CI = 10.9-69.2%) and 27% (95% CI = 6.0-61%). LIMITATIONS, REASONS FOR CAUTION: The overall response rate for clinics was 53.6%. Therefore, it is not only that patients may not have been included, but also that those that were included were biased towards the University sector with a response rate of 83% (25/30) for a small number of patients. WIDER IMPLICATIONS OF THE FINDINGS: According to literature, malignant disease is a risk factor for a poor response to COS. However, patients having emergency IVF before gonadotoxic treatment have a reasonable chance of pregnancy after embryo replacement. Embryo freezing is a valuable approach that should be included among the strategies used to preserve fertility. STUDY FUNDING/COMPETING INTEREST(S): No external funding was sought for this study. None of the authors has any conflict of interest to declare.


Assuntos
Criopreservação/métodos , Fertilização In Vitro/métodos , Indução da Ovulação/métodos , Taxa de Gravidez , Adulto , Estudos de Coortes , Transferência Embrionária , Emergências , Estradiol/sangue , Feminino , Humanos , Infertilidade Feminina/etiologia , Infertilidade Feminina/prevenção & controle , Neoplasias/complicações , Gravidez , Estudos Retrospectivos , Adulto Jovem
9.
Rev. argent. endocrinol. metab ; 50(2): 63-70, jul. 2013. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-694891

RESUMO

Ante la baja frecuencia del carcinoma medular de tiroides (CMT), en el Departamento de Tiroides de SAEM nos propusimos realizar un estudio de cohorte, observacional, retrospectivo y multicéntrico. Se incluyeron 219 pacientes con diagnóstico histológico de CMT. El 65 % fueron mujeres, la edad promedio fue de 39 ± 20 años (1 a 84 años); 44-% de los casos fueron familiares. Las formas de presentación más frecuentes fueron nódulo tiroideo (58 %) y pesquisa genética por antecedente familiar (22 %). Si bien la citología tiroidea fue diagnóstica de CMT en el 39 % de los casos, fue determinante de indicación quirúrgica en el 79 %. En el 47 % de los pacientes el diagnóstico de CMT se obtuvo previamente al tratamiento quirúrgico inicial por punción aspiración con aguja fina (PAAF), estudio genético o nivel de calcitonina (CT)). El 65 % se presentó en estadios avanzados (TNM III y IV). El estudio del protoncogen RET se realizó en 162 pacientes (74 %). En el 49 % se observó mutación siendo la más frecuente (76 %) en el codón 634. La forma hereditaria más frecuentemente observada fue el síndrome de neoplasia endocrina múltiple (NEM) 2A (57 % de los casos familiares), seguida por carcinoma medular familiar (25 %) y NEM 2B (13 %). Los casos familiares tuvieron menor edad al diagnóstico y mayor frecuencia de diagnóstico prequirúrgico. Los casos índice tuvieron mayor edad al momento del diagnóstico, mayores niveles de antígeno carcinoembrionario (CEA) y CT prequirúrgicos, mayor proporción de estadios III y IV y mayor porcentaje de evidencia de enfermedad al momento de la última consulta que aquellos detectados por pesquisa. En 143 pacientes (65 %) se obtuvieron registros completos de seguimiento en los que se analizaron los factores relacionados con la evolución. La mediana de seguimiento fue de 44 meses: fallecieron 21 pacientes (14,6 %) y 122 (86 %) viven; 76 de estos (54 %) se encuentran libres de enfermedad. El grupo con evidencia de enfermedad se presentó en estadios más avanzados. Resultaron factores de mayor riesgo para evidencia de enfermedad: sexo masculino, CMT esporádico, niveles elevados de CT prequirúrgicos, estadio IV y presencia de metástasis. Los niveles de CT posquirúrgicos fueron menores en aquellos pacientes que en la evolución final no presentaron evidencia de enfermedad. El principal factor pronóstico de la evolución de los pacientes con CMT fue el estadio de presentación, determinando la importancia del diagnóstico precoz con el fin de poder implementar un tratamiento quirúrgico curativo en estadios menos avanzados.


Due to the low frequency of medullary thyroid cancer (MTC), an observational, cohort, retrospective multicenter study was conducted at the Thyroid Department of the Endocrine and Metabolism Argentine Society (SAEM). We included 219 patients with histologically proven MTC, with a mean age of 39 ± 20 yr (range 1-84 years). Sixty five percent were women and 44% were familial cases. The most common presentations were thyroid nodule (58 %) and genetic screening due to family history (22 %). In 39 % of patients, diagnosis of MTC was made by fine needle aspiration, but cytology led to surgery in 79 %. In 47 % of patients, MTC was diagnosed by cytology, calcitonin (CT) levels or genetic studies prior to initial surgery. Sixty five percent of patients had advanced stages of the disease (TNM III or IV) at diagnosis. Proto-oncogene RET was studied in 162 patients (74 %). In 49% a mutation was reported, most frequently in codon 634 (76 %). Regarding hereditary forms of MTC, MEN 2A was the most frequent (57%), followed by familial MTC in 25 % and MEN 2B in 13 % of cases. Familial cases were younger subjects and had more frequently a pre-surgery diagnosis. Index cases were older, with higher CEA and CT levels, presented in more advanced stages and had more frequently evidence of disease at final assessment than patients who were diagnosed by genetic screening. Follow-up records of 143 patients were analyzed (65%); median time was 44 months; 21 patients died (14.6 %) and 122 survived (86 %), 76 showed no evidence of disease (NED) (54 %). High risk factors for evidence of disease at the final evaluation were: male gender, sporadic MTC, higher CT pre-surgery levels, stage IV and metastasis. Post surgery CT levels were lower in patients with NED. Stage at initial diagnosis was the main prognostic factor in patients with MTC, determining the importance of early detection for performing curative surgery in less advanced stages.

10.
Rev. argent. endocrinol. metab ; 50(2): 63-70, jul. 2013. ilus, tab
Artigo em Espanhol | BINACIS | ID: bin-130696

RESUMO

Ante la baja frecuencia del carcinoma medular de tiroides (CMT), en el Departamento de Tiroides de SAEM nos propusimos realizar un estudio de cohorte, observacional, retrospectivo y multicéntrico. Se incluyeron 219 pacientes con diagnóstico histológico de CMT. El 65 % fueron mujeres, la edad promedio fue de 39 ± 20 años (1 a 84 años); 44-% de los casos fueron familiares. Las formas de presentación más frecuentes fueron nódulo tiroideo (58 %) y pesquisa genética por antecedente familiar (22 %). Si bien la citología tiroidea fue diagnóstica de CMT en el 39 % de los casos, fue determinante de indicación quirúrgica en el 79 %. En el 47 % de los pacientes el diagnóstico de CMT se obtuvo previamente al tratamiento quirúrgico inicial por punción aspiración con aguja fina (PAAF), estudio genético o nivel de calcitonina (CT)). El 65 % se presentó en estadios avanzados (TNM III y IV). El estudio del protoncogen RET se realizó en 162 pacientes (74 %). En el 49 % se observó mutación siendo la más frecuente (76 %) en el codón 634. La forma hereditaria más frecuentemente observada fue el síndrome de neoplasia endocrina múltiple (NEM) 2A (57 % de los casos familiares), seguida por carcinoma medular familiar (25 %) y NEM 2B (13 %). Los casos familiares tuvieron menor edad al diagnóstico y mayor frecuencia de diagnóstico prequirúrgico. Los casos índice tuvieron mayor edad al momento del diagnóstico, mayores niveles de antígeno carcinoembrionario (CEA) y CT prequirúrgicos, mayor proporción de estadios III y IV y mayor porcentaje de evidencia de enfermedad al momento de la última consulta que aquellos detectados por pesquisa. En 143 pacientes (65 %) se obtuvieron registros completos de seguimiento en los que se analizaron los factores relacionados con la evolución. La mediana de seguimiento fue de 44 meses: fallecieron 21 pacientes (14,6 %) y 122 (86 %) viven; 76 de estos (54 %) se encuentran libres de enfermedad. El grupo con evidencia de enfermedad se presentó en estadios más avanzados. Resultaron factores de mayor riesgo para evidencia de enfermedad: sexo masculino, CMT esporádico, niveles elevados de CT prequirúrgicos, estadio IV y presencia de metástasis. Los niveles de CT posquirúrgicos fueron menores en aquellos pacientes que en la evolución final no presentaron evidencia de enfermedad. El principal factor pronóstico de la evolución de los pacientes con CMT fue el estadio de presentación, determinando la importancia del diagnóstico precoz con el fin de poder implementar un tratamiento quirúrgico curativo en estadios menos avanzados.(AU)


Due to the low frequency of medullary thyroid cancer (MTC), an observational, cohort, retrospective multicenter study was conducted at the Thyroid Department of the Endocrine and Metabolism Argentine Society (SAEM). We included 219 patients with histologically proven MTC, with a mean age of 39 ± 20 yr (range 1-84 years). Sixty five percent were women and 44% were familial cases. The most common presentations were thyroid nodule (58 %) and genetic screening due to family history (22 %). In 39 % of patients, diagnosis of MTC was made by fine needle aspiration, but cytology led to surgery in 79 %. In 47 % of patients, MTC was diagnosed by cytology, calcitonin (CT) levels or genetic studies prior to initial surgery. Sixty five percent of patients had advanced stages of the disease (TNM III or IV) at diagnosis. Proto-oncogene RET was studied in 162 patients (74 %). In 49% a mutation was reported, most frequently in codon 634 (76 %). Regarding hereditary forms of MTC, MEN 2A was the most frequent (57%), followed by familial MTC in 25 % and MEN 2B in 13 % of cases. Familial cases were younger subjects and had more frequently a pre-surgery diagnosis. Index cases were older, with higher CEA and CT levels, presented in more advanced stages and had more frequently evidence of disease at final assessment than patients who were diagnosed by genetic screening. Follow-up records of 143 patients were analyzed (65%); median time was 44 months; 21 patients died (14.6 %) and 122 survived (86 %), 76 showed no evidence of disease (NED) (54 %). High risk factors for evidence of disease at the final evaluation were: male gender, sporadic MTC, higher CT pre-surgery levels, stage IV and metastasis. Post surgery CT levels were lower in patients with NED. Stage at initial diagnosis was the main prognostic factor in patients with MTC, determining the importance of early detection for performing curative surgery in less advanced stages.(AU)

11.
Gynecol Obstet Fertil ; 40(7-8): 411-8, 2012.
Artigo em Francês | MEDLINE | ID: mdl-22521986

RESUMO

OBJECTIVE: To evaluate the results of controlled ovarian hyperstimulation (COH) for IVF in patients with low anti-Müllerian hormone (AMH) and normal basal follicle stimulating hormone (FSH) and Estradiol levels (≤50 pg/mL). PATIENTS AND METHODS: A retrospective cohort study including 704 patients for whom AMH and FSH levels (measured between days 3 and 5 of the menstrual cycle) were available, is performed in the IVF center at the Sèvres Hospital (France). Three groups are designed and analyzed: group 1 with AMH less or equal to 2 ng/mL and FSH less or equal to 10 mUI/mL (study group), Group 2 with AMH greater than 2 ng/mL and FSH less or equal to 10 mUI/mL (control group) and Group 3 with AMH less or equal to 2 ng/mL and FSH greater than 10 mUI/mL (group with decreased ovarian reserve). RESULTS: IVF outcome for patients from the study group is significantly worse than that of the second but not than that of the third group. In the first group, the number of retrieved oocytes, the number of total obtained embryos, the clinical pregnancy rate and the live birth rate are significantly lower than in the second group; moreover, there are more cancelled cycles because of poor response in the first group. There is no difference with the third group. DISCUSSION AND CONCLUSIONS: This study shows that women with a low baseline AMH have a similar response to COH to the poor responders patients with a decreased ovarian reserve revealed by an elevated FSH level. Thus, when a woman undergoing IVF cycle presents a low AMH, she might be considered as a poor responder patient regardless of the FSH level and, although the clinical pregnancy rate is not so disappointing (18%), the couple should be informed of a higher risk of cycle cancellation.


Assuntos
Hormônio Antimülleriano/sangue , Estradiol/sangue , Fertilização In Vitro , Hormônio Foliculoestimulante/sangue , Indução da Ovulação , Adulto , Coeficiente de Natalidade , Feminino , Humanos , Recuperação de Oócitos , Gravidez , Taxa de Gravidez , Prognóstico , Estudos Retrospectivos
12.
J Biomech Eng ; 133(9): 094507, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22010753

RESUMO

Blood damage and thrombosis are major complications that are commonly seen in patients with implanted mechanical heart valves. For this in vitro study, we isolated the closing phase of a bileaflet mechanical heart valve to study near valve fluid velocities and stresses. By manipulating the valve housing, we gained optical access to a previously inaccessible region of the flow. Laser Doppler velocimetry and particle image velocimetry were used to characterize the flow regime and help to identify the key design characteristics responsible for high shear and rotational flow. Impact of the closing mechanical leaflet with its rigid housing produced the highest fluid stresses observed during the cardiac cycle. Mean velocities as high as 2.4 m/s were observed at the initial valve impact. The velocities measured at the leaflet tip resulted in sustained shear rates in the range of 1500-3500 s(-1), with peak values on the order of 11,000-23,000 s(-1). Using velocity maps, we identified regurgitation zones near the valve tip and through the central orifice of the valve. Entrained flow from the transvalvular jets and flow shed off the leaflet tip during closure combined to generate a dominant vortex posterior to both leaflets after each valve closing cycle. The strength of the peripheral vortex peaked within 2 ms of the initial impact of the leaflet with the housing and rapidly dissipated thereafter, whereas the vortex near the central orifice continued to grow during the rebound phase of the valve. Rebound of the leaflets played a secondary role in sustaining closure-induced vortices.


Assuntos
Circulação Sanguínea , Próteses Valvulares Cardíacas/efeitos adversos , Desenho de Prótese , Hemodinâmica , Humanos , Imageamento Tridimensional , Fluxometria por Laser-Doppler , Falha de Prótese
13.
Rev. argent. endocrinol. metab ; 48(3): 149-157, set. 2011. graf, tab
Artigo em Espanhol | LILACS | ID: lil-642002

RESUMO

Introducción: La presencia de nódulos tiroideos palpables en la población general, es uno de los signos clínicos tiroideos más frecuentes en la práctica diaria. Objetivos: 1) establecer la prevalencia de las distintas patologías en bocio nodular único palpable y analizar sus características y su relación con los resultados citológicos. 2) analizar la existencia de diferencias regionales en Argentina. Pacientes y Métodos: Estudio prospectivo de 739 pacientes con bocio nodular único palpable evaluados entre el 1/1/2000 y el 31/12/2001 en Centros de Buenos Aires, Bahía Blanca, Mendoza y La Pampa. Se recabaron datos de examen clínico, ecografía tiroidea, TSH, ATPO y citología por punción con aguja fina. (PAAF). Fue utilizado para el análisis estadístico Correlación de Pearson, X2 y Test de Fisher. Resultados: la edad (X ± DS) fue 46,3 ± 14 años, 93,1 % eran de sexo femenino. El 1,6 % tenía historia de radiación en cuello y el 29,9 % antecedentes familiares de patología tiroidea. Hallazgos clínicos: disfagia en el 7,9 %, disfonía 3,5 %, crecimiento nodular en los últimos 6 meses 19,2 %, consistencia dura el 24,7 %, fijeza a estructuras adyacentes 1,5 % y adenopatías en el 3 %. Hallazgos bioquímicos: TSH normal en el 81,2 % y ATPO positivos en el 30,3 % de los casos. Características Ecográficas: nódulos sólidos: 53,1 %, hipoecoicos: 63,8 %, microcalcificaciones 10,3 %, halo incompleto: 15 %, multinodular: 30,5 %, tiroides heterogénea: 60,2 % y adenopatías: 3,8 %. Hallazgos citológicos: En el 86,8 % de los casos fue necesario solo una punción para llegar al diagnóstico. Insatisfactorio (excluyendo quiste): 3,2 %: benignos: 77,3 %; sospechosos: 12,6 % y cáncer: 7 % (42 papilar, 2 medular y 3 sin especificar). Una correlación significativa (p<0,02) fue observada entre citología maligna y crecimiento rápido, dureza, fijeza a estructuras vecinas, nódulo sólido, halo incompleto y adenopatías aunque estos parámetros son más frecuentes en números absolutos en nódulos benignos. La mayoría de las cirugías fueron indicadas en base al hallazgo citológico. El diagnóstico histológico de los 96 pacientes que fueron operados mostró 51 carcinomas, de los cuales solo dos tenían citología benigna y 31 adenomas. Conclusión: Los nódulos palpables únicos fueron más frecuentes en mujeres eutiroideas en la edad media de la vida. Un tercio tenía historia familiar de patología tiroidea, similar al porcentaje hallado de ATPO positivos. Por ecografía los nódulos fueron predominantemente sólidos, hipoecoicos, únicos con resto de la glándula tiroides heterogénea. La PAAF fue predominantemente benigna. El crecimiento rápido, la dureza, la fijeza a estructuras adyacentes, el halo incompleto y la presencia de adenopatías fueron relacionados con malignidad, pero la benignidad fue más frecuente. En la mayoría de los pacientes la cirugía fue recomendada por los hallazgos citológicos. Nuestros resultados son similares a los reportados en otras áreas geográficas.


Introduction: the presence of palpable thyroid nodules in the general population is one of the most common clinical signs of thyroid disease in daily practice. Objectives: 1) To assess the prevalence of pathologies, clinical and cytological findings of single palpable thyroid nodules (SPTN) in Argentina. 2) Analyze the regional differences in Argentina. Methods: Prospective study of 739 patients with STPN were evaluated at centres in Buenos Aires, Bahía Blanca, Mendoza, and La Pampa between 1/1/00 and 12/31/01. Clinical examination, thyroid ultrasound scan (US), TSH, TPOAb and fine needle aspirations (FNA) were performed. Statistics: Pearson Correlation, X2 & Fisher Tests. Results: Age (X ± SD) 46 ± 14ys: 93.1 % were women. Previous history of neck radiation & familial thyroid disease were found in 1.6 and 29.9 % respectively. Clinical findings: dysphagia: 7.9 %; dysphonia: 3.5%; nodule growth: 19.2 %; hard consistence: 24.7 %; fixation to adjacent structure: 1.5 % and lymphadenopathies (ADP): 3 %. Biochemical findings: TSH was normal in 81.2 % & TPOAb+ in 30.3 %. US features: solid: 53.1 %; hypoechoic: 63.8 %; microcalcifications: 10.3 %; incomplete halo: 15 %; more than 1 nodule: 30.5 %; thyroid heterogeneity: 60.2 % and ADP: 3.8 %. Cytology: Only 1 FNA was needed in 86.8%. Unsatisfactory (excluding cysts): 3.2 %; benign: 77.2%; suspicious: 12.6 % and cancer: 7 % (42 papillary, 2 medullary and 3 non specified). A significant correlation (p<0.02) was established between malignant nodules and rapid growth, hard, fixed, solid nodule, incomplete halo and ADP, though these parameters were more frequent (in absolute number) in benign nodules. Surgery was mainly indicated based on FNA results. Histological diagnosis of 96 patients who underwent surgery showed 51 carcinomas, of which only 2 were cytologically benign and 31 adenomas. Conclusion: Palpable single nodules were more frequent in middle aged euthyroid women. One third had familial thyroid pathology, similar to the presence of TPOAb. On US, nodules were predominantly solid, hypoechoic, single with heterogeneous thyroid gland. FNA was predominantly benign. Rapid growth, hard, fixed, solid nodule, incomplete halo and ADP were associated with malignancy, but benignity was more common. In most of the patients surgery was recommended based on cytological findings. Our results are similar to those reported in other geographic areas.

14.
Gynecol Obstet Fertil ; 39(1): 49-52, 2011 Jan.
Artigo em Francês | MEDLINE | ID: mdl-21186132

RESUMO

The authors report a case of septo-optic dysplasia discovered during the pregnancy without another abnormality. It's a rare cerebral abnormality that is characterized by an absence of septum pellucidum associated to a hypoplasia of ways and optic chiasm to variable degrees. Discovery is often made for adulthood. Future is extremely wide. It is determined with the arisen to different degrees of incapacity of Pituitary gland, psychomotor delay of variable intensity with mental deficiency, a visual confusion, and a confusion of the regulation of the temperature.


Assuntos
Displasia Septo-Óptica/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adulto , Algoritmos , Feminino , Humanos , Gravidez , Displasia Septo-Óptica/diagnóstico
15.
J Gynecol Obstet Biol Reprod (Paris) ; 39(8 Suppl 2): S53-66, 2010 Dec.
Artigo em Francês | MEDLINE | ID: mdl-21185487

RESUMO

The different options of fertility preservation must be approached with all patients before initiating any cancer therapy and physicians should refer each patient treated during their reproductive years to specialists in a specialized center that will evaluate the best available alternatives to preserve male and female fertility.The only efficiently proven ways of fertility preservation are sperm cryopreservation for men and embryo cryopreservation to preserve couple fertility. However, the recent progress observed with oocyte cryopreservation (in particular the oocyte vitrification) may change our practices in the future if vitrification is allowed in France. Although the law of Bioethics of 2004 authorizes the ovarian cryopreservation today, its modalities of use stay at present at the stage of the research. But in spite of the low number of published births today in France and in the world, the ovarian tissue cryopreservation is a promising technique. It remains the last possible alternative to protect fertility of prepubertal girls. The sperm cryopreservation must be systematically proposed to all men (even teenagers) undergoing a treatment for cancer potentially harmful for their fertility whatever their sperm quality. The testicular tissue cryopreservation is also a method to be discussed for adults, teenagers in case of failure of sperm banking or for prepubertal boys.


Assuntos
Infertilidade/etiologia , Infertilidade/prevenção & controle , Neoplasias/terapia , Adolescente , Adulto , Antineoplásicos/efeitos adversos , Criança , Criopreservação , Árvores de Decisões , Feminino , Fertilidade , Humanos , Masculino , Radioterapia/efeitos adversos
16.
Gynecol Obstet Fertil ; 38(11): 690-2, 2010 Nov.
Artigo em Francês | MEDLINE | ID: mdl-21115382

RESUMO

A 30-year-old woman undergoing an In Vitro Fertilization (IVF) treatment for tubal infertility and for whom no oocyte was retrieved at the puncture ("white puncture") presented an ectopic pregnancy. The patient was asymptomatic except some bleeding events reported for several days prior to the puncture. The ovulation monitoring was normal throughout the stimulation by gonadotrophin and hCG was administered for the final oocyte maturation on the twelfth day of stimulation at a rate of 2771 pg/ml of estradiol with a perfect ultrasound follicular growth. This case demonstrates that we have to beware of a "white puncture" and that the hCG measurement the day of the oocyte retrieval is necessary because of the possibility of an ectopic pregnancy.


Assuntos
Fertilização In Vitro/efeitos adversos , Infertilidade Feminina/terapia , Recuperação de Oócitos/métodos , Oócitos , Gravidez Ectópica/etiologia , Adulto , Gonadotropina Coriônica/sangue , Gonadotropina Coriônica/uso terapêutico , Estradiol/sangue , Feminino , Humanos , Indução da Ovulação/efeitos adversos , Indução da Ovulação/métodos , Gravidez , Gravidez Ectópica/diagnóstico , Gravidez Ectópica/diagnóstico por imagem , Ultrassonografia Pré-Natal
17.
Rev. argent. endocrinol. metab ; 47(3): 18-24, jul.-set. 2010. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-641974

RESUMO

El carcinoma diferenciado de tiroides en quiste tirogloso (CaQT) es una rara entidad. En diferentes series de pacientes operados por quistes tiroglosos su incidencia fue del 0.7 al 1.07%. Luego de la extirpación del quiste por el procedimiento de Sistrunk, no hay consenso sobre la indicación de tiroidectomía total, radioablación y/o terapéutica supresiva con levotiroxina. El objetivo del Departamento de tiroides de SAEM, fue evaluar: formas de presentación, evolución clínica, métodos diagnósticos de utilidad y tratamiento para consensuar futuras conductas. Material y Métodos: Estudio multicéntrico, retrospectivo en 22 pacientes entre 10 a 69 años, 15 mujeres y 7 varones. Resultados: El tamaño de los quistes osciló entre 1 y 8 cm (Mediana= 3.0 cm, Χ ± DS= 3.7 ± 2.2 cm). La mitad de los pacientes presentó crecimiento del quiste en los 6 meses previos a la cirugía. La punción resultó sospechosa en 2/5 quistes y positiva en uno. La ecografía tiroidea evidenció nódulos en 4/13 casos (30%). Se realizó tiroidectomía en 17/22 pacientes (total: 15 y subtotal: 2). La histología del CaQT demostró carcinoma papilar en 21 y carcinoma folicular en uno. Hubo coexistencia de cáncer intratiroideo en el 23.5% de los casos, ninguno multicéntrico. Dos pacientes presentaron metástasis ganglionares y otro tuvo compromiso muscular (ninguno de ellos coexistió con cáncer intratiroideo). Se radioablacionó a 13 pacientes. En 9/11 pacientes la tiroglobulina permaneció indetectable durante el seguimiento (1 a 14 años). Conclusiones: 1) Realizar ecografía de cuello y punción ecoguiada a todo paciente con quiste tirogloso. 2) En caso de CaQT combinar simultáneamente tiroidectomía total y procedimiento de Sistrunk. 3) Evaluar radioablación complementaria y tratamiento supresivo con levotiroxina en cada caso. 4) Efectuar el seguimiento tal como en los carcinomas ortotópicos.


Differentiated thyroid carcinoma (DTC) in thyroglosal duct cyst (TGDC) is rare, ranging from 0.7 to 1.07% in different series. After the surgery of choice (Sistrunk procedure) the other alternative treatments such as thyroidectomy (Tx), radioiodine and L-T4 therapy are controversial. OBJECTIVE: to evaluate several and controversial aspects in the largest series of DTC in TGDC reported in the literature. Subjects and methods: retrospective multicentric study: n= 22, aged 10-69 yrs. (15 females and 7 men) who underwent the Sistrunk procedure for TGDC. Results: none of the TGDC was less than 1 cm (median 3.0 cm, Χ±SD= 3.7 ± 2.2cm). In half of them there was an increased cystic size in the last 6 months before surgery. Cyst FNA was suspicious in 2/5 and positive in one, whereas the histological diagnosis of the operated TGCD was papillary cancer in 21 and 1 follicular carcinoma. Thyroid ultrasound (US) (n=13) showed nodules in 30% of the cases. Tx was performed in 17/22 (total: 15, subtotal: 2). Thyroid DTC coexisted in 4/17 (23.5%), and was unilateral in all of them. Lymph node metastases were present in 2 adults and muscle involvement was found in the 10-year old girl. None of these 3 patients had overt thyroid lesions. 131-I therapy was performed in 10 patients. In 9 out of 11 subjects Tg remained undetectable during follow-up (1-14yrs.). Persistent high Tg was present in one case without thyroid DTC. Conclusions: 1) Ultrasonography and FNAB should be performed to every patient with thyroglossal duct cyst 2) In case of TGDC, total Tx and Sistrunk's procedure should be simultaneously combined 3) 131-I therapy and L-T4 suppressive treatment should be evaluated in every case 4) Follow-up as in the DTC.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Cisto Tireoglosso/cirurgia , Cisto Tireoglosso/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/terapia , Terapia de Salvação/métodos
18.
J Med Device ; 4(1): 11001, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20209095

RESUMO

The fluid dynamics during valve closure resulting in high shear flows and large residence times of particles has been implicated in platelet activation and thrombus formation in mechanical heart valves. Our previous studies with bi-leaflet valves have shown that large shear stresses induced in the gap between the leaflet edge and the valve housing results in relatively high platelet activation levels whereas flow between the leaflets results in shed vortices not conducive to platelet damage. In this study we compare the result of closing dynamics of a tilting disc valve with that of a bi-leaflet valve. The two-dimensional fluid-structure interaction analysis of a tilting disc valve closure mechanics is performed with a fixed grid Cartesian mesh flow solver with local mesh refinement, and a Lagrangian particle dynamic analysis for computation of potential for platelet activation. Throughout the simulation the flow remains in the laminar regime and the flow through the gap width is marked by the development of a shear layer which separates from the leaflet downstream of the valve. Zones of re-circulation are observed in the gap between the leaflet edge and the valve housing on the major orifice region of the tilting disc valve and are seen to be migrating towards the minor orifice region. Jet flow is observed at the minor orifice region and a vortex is formed which sheds in the direction of fluid motion as observed in experiments using PIV measurements. The activation parameter computed for the tilting disc valve, at the time of closure was found to be 2.7 times greater than that of the bi-leaflet mechanical valve and was found to be in the vicinity of the minor orifice region mainly due to the migration of vortical structures from the major to the minor orifice region during the leaflet rebound of the closing phase.

20.
Gynecol Obstet Fertil ; 35(3): 240-8, 2007 Mar.
Artigo em Francês | MEDLINE | ID: mdl-17321188

RESUMO

The link between hypothyroidism and infertility is still a matter of debate. Hypothyroidism can result in cycle disturbances, such as oligomennorhea and functional bleeding. Additionally, several studies have shown that thyroid autoimmunity (detection of anti peroxydase antibodies) may account for the occurrence of repetitive miscarriages. In infertility work-up, screening thyroid function should be specifically recommended for women with clinical hypothyroidism, with a personal, familial history of thyroid or other auto immune diseases (such as type I diabetes) as well as for women with unexplained anovulation or functional bleeding. Moreover, detection of thyroid antibody seems to be worthwhile for the assessment of recurrent miscarriages, due to the potential benefit of thyroid supplementation. In pregnant women, assessment of thyroid function seems specifically crucial to ensure adequate foetal development. Indeed, it has been well established that untreated maternal hypothyroidism may be associated with disturbances of brain development and low intellectual quotient. Additionally, other foetal (growth deficiency, premature birth, low birth weight) as well as maternal (gestational hypertension, pre-eclampsia...) complications have been also reported in pregnant women with untreated hypothyroidism. Consequently, screening of thyroid function should be performed in every woman at risk of thyroid disease. Recent studies even advocate that thyroid screening should be extended to the overall pregnant population. The objective is to adjust L-thyroxin supplementation to maintain serum TSH concentrations below the threshold of 2.5 mUI/l. Finally, iodine deficiency, currently observed in pregnant women, should be prevented by iodine supply prior to conception, during pregnancy and during breast feeding as well.


Assuntos
Hipotireoidismo/complicações , Hipotireoidismo/diagnóstico , Infertilidade Feminina/etiologia , Complicações na Gravidez , Aborto Habitual/etiologia , Aborto Espontâneo/etiologia , Feminino , Humanos , Hipotireoidismo/imunologia , Recém-Nascido , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/etiologia , Complicações na Gravidez/imunologia , Tireoidite Autoimune/complicações , Tireoidite Autoimune/diagnóstico
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