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1.
Chembiochem ; 25(6): e202300722, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38235523

RESUMO

We report the first biocatalytic modification of sesquiterpene lactones (STLs) found in the chicory plants, specifically lactucin (Lc), 11ß,13-dihydrolactucin (DHLc), lactucopicrin (Lp), and 11ß,13-dihydrolactucopicrin (DHLp). The selective O-acylation of their primary alcohol group was carried out by the lipase B from Candida antarctica (CAL-B) using various aliphatic vinyl esters as acyl donors. Perillyl alcohol, a simpler monoterpenoid, served as a model to set up the desired O-acetylation reaction by comparing the use of acetic acid and vinyl acetate as acyl donors. Similar conditions were then applied to DHLc, where five novel ester chains were selectively introduced onto the primary alcohol group, with conversions going from >99 % (acetate and propionate) to 69 % (octanoate). The synthesis of the corresponding O-acetyl esters of Lc, Lp, and DHLp was also successfully achieved with near-quantitative conversion. Molecular docking simulations were then performed to elucidate the preferred enzyme-substrate binding modes in the acylation reactions with STLs, as well as to understand their interactions with crucial amino acid residues at the active site. Our methodology enables the selective O-acylation of the primary alcohol group in four different STLs, offering possibilities for synthesizing novel derivatives with significant potential applications in pharmaceuticals or as biocontrol agents.


Assuntos
Cichorium intybus , Sesquiterpenos , Ésteres/química , Simulação de Acoplamento Molecular , Acilação , Lactonas
2.
Gynecol Obstet Fertil ; 28(2): 115-9, 2000 Feb.
Artigo em Francês | MEDLINE | ID: mdl-10758585

RESUMO

The ovarian hyperstimulation treatment increases results of in vitro fertilization. However, the risk of ovarian hyperstimulation syndrome must be carefully evaluated for each patient. An excessive response increases complication and cancellation rates. Coasting could be applied when an excessive response occurred. This method requires stopping gonadotropin administration while GnRH agonist is continued. When the estradiol rate decreases, the hCG administration is allowed. In the literature, results shows adequate pregnancy rates, between 26 and 64%. It seems oocyte quality was not spoiled. However, coasting does not eliminate definitively the risk of ovarian hyperstimulation syndrome. Coasting method could be a safe and efficient method to treat an excessive ovarian response during in vitro fertilization protocol. Pregnancy rates seem to be preserved.


Assuntos
Gonadotropina Coriônica/uso terapêutico , Monitoramento de Medicamentos/métodos , Estradiol/sangue , Fármacos para a Fertilidade Feminina/uso terapêutico , Hormônio Liberador de Gonadotropina/agonistas , Infertilidade Feminina/tratamento farmacológico , Menotropinas/uso terapêutico , Síndrome de Hiperestimulação Ovariana/etiologia , Síndrome de Hiperestimulação Ovariana/prevenção & controle , Indução da Ovulação/efeitos adversos , Indução da Ovulação/métodos , Gonadotropina Coriônica/farmacologia , Protocolos Clínicos , Transferência Embrionária , Feminino , Atresia Folicular/efeitos dos fármacos , Humanos , Infertilidade Feminina/sangue , Infertilidade Feminina/diagnóstico por imagem , Menotropinas/farmacologia , Gravidez , Resultado da Gravidez , Fatores de Risco , Ultrassonografia
3.
Hum Reprod ; 14(12): 3035-40, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10601093

RESUMO

Based on the analysis of the most frequent mutations responsible for cystic fibrosis (CF), a higher than expected frequency of CF mutations was recently reported in men with infertility due to reduced sperm quality. To further document whether this condition is associated with severe or mild abnormalities of cystic fibrosis transmembrane conductance regulator (CFTR) functions, we carried out a complete scanning of CFTR sequences using a strategy that detects almost all 850 mutations and 150 polymorphisms reported to date in the CFTR gene. We have investigated a cohort of 56 patients with severe oligoasthenoteratozoospermia (OAT) and 50 controls from southern France for CFTR gene mutations and variations. The frequencies of CF-causing mutations and CFTR variations identified in this OAT sample did not differ significantly from the frequencies found in the normal population. However, we observed a 1.7-fold increase in the proportion of homozygotes for a specific CFTR haplotype (TG11-T7-G1540) in the OAT group (P = 0.025). Our results do not confirm a link between CF mutations and reduced sperm quality. Further studies are needed to substantiate the hypothesis that a combination of variants affecting expression and function of the CFTR protein is associated with male infertility.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Testes Genéticos , Infertilidade Masculina/genética , Mutação , Sequência de Bases/genética , Estudos de Coortes , Feminino , Variação Genética , Humanos , Infertilidade Masculina/fisiopatologia , Masculino , Valores de Referência , Espermatozoides/fisiologia
4.
Contracept Fertil Sex ; 26(7-8): 564-7, 1998.
Artigo em Francês | MEDLINE | ID: mdl-9810132

RESUMO

Obesity was defined by a body mass index more than 30 kg/m2. Many risks were related to this pathology, and sometimes, menstrual disorders or infertility. In order to obtain an adequate response to ovarian stimulation during IVF cycles, higher doses of menotropins are necessary in the group of obese patients. The mechanism of this phenomenon is still unclear. Leptin is one of the main hypothesis, and could act on obesity and reproductive system simultaneously. The likelihood to have an ongoing pregnancy after IVF treatment is less in the group of obese patients because of the increased risk of miscarriage and obstetrical complications. Weight loss prior IVF remains the main advice in order to decrease the risks of the procedure and to treat successfully these patients.


Assuntos
Fertilização in vitro , Obesidade , Indução da Ovulação/métodos , Índice de Massa Corporal , Feminino , Gonadotropinas/administração & dosagem , Humanos , Obesidade/complicações , Síndrome do Ovário Policístico/complicações
5.
Hum Reprod ; 13(7): 1936-44, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9740453

RESUMO

This study aims to report the willingness of different populations of high-risk couples to undergo preimplantation genetic diagnosis (PGD) for beta-thalassaemia as an alternative to prenatal genetic diagnosis (PND), and the willingness of infertile couples to undergo PGD for aneuploidies. An information sheet and questionnaire presenting PGD and PND procedures were distributed to four population types: 54 high-risk couples for beta-thalassaemia coming for their first PND (population A); 51 similar couples coming for their second or further PND without previous experience of therapeutic abortion (population B-na); 50 similar couples coming for their second or further PND with previous experience of therapeutic abortion for beta-thalassaemia-affected fetus (population B-ab); and 74 infertile couples undergoing routine in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) (population C). Favourable first impressions towards PGD compared with PND were observed in all four populations in the following proportions: 79.6% population A; 76.5% population B-na; 92.0% population B-ab; and 96.0% population C. Willingness to undergo PGD for beta-thalassaemia was as follows: 44.4% population A; 47.1% population B-na; and 72.0% population B-ab. We conclude that previous experience of PND for beta-thalassaemia is a crucial point in the willingness to accept the PGD procedure, and that couples belonging to population B-ab are the most suitable to undergo PGD for beta-thalassaemia. Some 96.0% of infertile couples in population C were ready to undergo PGD for aneuploidies.


Assuntos
Aneuploidia , Desenvolvimento Embrionário , Diagnóstico Pré-Natal , Talassemia beta/diagnóstico , Talassemia beta/genética , Aborto Terapêutico , Amostra da Vilosidade Coriônica , Feminino , Fertilização in vitro/métodos , Humanos , Masculino , Microinjeções , Gravidez , Sicília
6.
Fertil Steril ; 69(6): 1020-5, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9627287

RESUMO

OBJECTIVE: To evaluate the implantation rate and pregnancy rate (PR) in patients with severe tubal factor infertility who were undergoing IVF. Patients who had undergone salpingectomy were compared with those who had not. DESIGN: A prospective randomized study. SETTING: A department of obstetrics and gynecology at a university hospital. PATIENT(S): Thirty patients who previously had undergone salpingectomy and 30 patients who had not undergone salpingectomy before IVF treatment. INTERVENTION(S): Laparoscopy with or without salpingectomy followed by IVF with the use of combined GnRH agonist and hMG therapy in a long stimulation protocol. MAIN OUTCOME MEASURE(S): Embryo implantation rate and ongoing PR per transfer. The cumulative PRs were compared for the two groups of patients. RESULT(S): After the first IVF attempt, the implantation rate was 10.4% in the group with salpingectomy and 4.6% in the group without salpingectomy. For all IVF attempts, the respective embryo implantation rates in the two groups were 13.4% and 8.6%. The ongoing PR per transfer was 34.2% in the group with salpingectomy compared with 18.7% in the group without salpingectomy. After four IVF attempts, the probability of becoming pregnant was greater in the group of patients with salpingectomy (75%) than in the group without salpingectomy (63%). CONCLUSION(S): Previous salpingectomy in patients with severe tubal factor infertility who are undergoing IVF seems to increase the embryo implantation rate and the PR per cycle of IVF. This monocentric study must be followed by other similar studies to allow for a metaanalysis and confirm this clear trend with definitive evidence.


Assuntos
Implantação do Embrião , Tubas Uterinas/cirurgia , Fertilização in vitro , Infertilidade Feminina/fisiopatologia , Infertilidade Feminina/cirurgia , Taxa de Gravidez , Adulto , Feminino , Humanos , Projetos Piloto , Gravidez , Probabilidade , Estudos Prospectivos
7.
Hum Reprod ; 11(7): 1393-8, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8671473

RESUMO

A gonadotrophin-releasing hormone agonist stimulation test determination of follicle stimulating hormone (FSH) concentrations before and 2 h after buserelin injection was carried out in 78 in-vitro fertilization cycles, and compared with basal FSH concentrations to predict ovarian response. Ovarian response was quantified by the ratio of peak oestradiol concentration divided by the total dose of human menopausal gonadotrophin (HMG) administered, the most reproducible parameter in 11 patients who underwent two treatment cycles. Stimulation outcome was highly related to the buserelin test, the best prognostic indicator being the sum of FSH concentrations. However, basal FSH concentration achieved similar correlations, even in those patients aged > 35 years. Sensitivity, specificity, positive and negative predictive values of basal FSH concentration and sum of FSH concentrations were similar. Low basal concentration and sum of FSH concentrations were both associated with a better ovarian response. Construction of receiver operator characteristic curves demonstrated that basal FSH concentration was more informative than the sum of FSH concentrations. Finally, the sum of FSH concentrations did not increase the prediction of ovarian response variability. We conclude that the buserelin test is strongly predictive of stimulation outcome, but is no more informative than the usual screening. We suggest that the performance of other stimulation tests should be clearly compared with that of basal FSH concentration.


Assuntos
Busserrelina , Fertilização in vitro , Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina/agonistas , Testes de Função Ovariana/métodos , Adulto , Busserrelina/administração & dosagem , Feminino , Humanos , Infertilidade/sangue , Infertilidade/fisiopatologia , Infertilidade/terapia , Menotropinas/administração & dosagem , Testes de Função Ovariana/estatística & dados numéricos , Indução da Ovulação , Curva ROC , Sensibilidade e Especificidade , Resultado do Tratamento
8.
Mol Reprod Dev ; 39(2): 141-6, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7826614

RESUMO

In in vitro fertilization (IVF) procedures, morphologic embryo grading is the sole criteria for selection of embryos transferable in utero. Cytogenetic analysis of preimplantation embryos was performed to investigate the relationship between chromosomal status and morphologic quality of preimplantation eggs. Aneuploidy was the most frequently observed abnormality. In addition, various types of aberrations such as polyploidy, haploidy, mosaicism, and fragmentation were also found. Our results, pooled with data drawn from previous reports, demonstrated the prognostic value of the embryo grading system as a means for eliminating chromosomally abnormal embryos. In contrast, data suggested that some aspects of the IVF process might be responsible for the occurrence of these abnormalities.


Assuntos
Blastocisto/citologia , Blastocisto/fisiologia , Cromossomos Humanos , Ploidias , Aneuploidia , Aberrações Cromossômicas , Transtornos Cromossômicos , Diploide , Feminino , Fertilização in vitro , Haploidia , Humanos , Mosaicismo , Poliploidia , Trissomia
9.
Fertil Steril ; 61(4): 741-5, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8150119

RESUMO

OBJECTIVE: To determine plasminogen activators (PAs) and PA inhibitor levels in seminal plasma of patients attending an infertility clinic. DESIGN: Quantification by immunologic method of PAs in seminal plasma. SETTING: Patients of Department of Urology and Andrology, University Hospital, Nimes, France. PATIENTS: Ninety-two men attending for assessment because of infertility. INTERVENTIONS: Semen were collected by masturbation. Usual sperm parameters were determined; immediately after liquefaction, samples were snap-frozen at -85 degrees C until used for immunologic determination. MAIN OUTCOME MEASURES: Tissue-type PA antigen, urokinase-type PA antigen, and type 1 PA inhibitor antigen levels in seminal plasma. RESULTS: Median values of PA were 270 ng/mL (tissue-type PA) and 5.4 ng/mL (urokinase-type PA) in normozoospermia; 290 ng/mL (tissue-type PA) and 5.7 ng/mL (urokinase-type PA) in oligozoospermia; 325 ng/mL (tissue-type PA) and 3.5 ng/mL (urokinase-type PA) in oligoasthenozoospermia. Type 1 PA inhibitor antigen levels were often under detection limit. Tissue-type PA was 173.5 ng/mL in semen with abnormal liquefaction and 290 ng/mL in semen with normal liquefaction. CONCLUSION: The study confirmed the presence of both types of PAs in seminal plasma, tissue-type PA being largely predominant. No difference was found in tissue-type PA, urokinase-type PA, or type 1 PA inhibitor antigen levels between normal and oligozoospermic semen nor between normal and asthenozoospermic semen. On the other hand, semen with abnormal liquefaction had significantly lower tissue-type PA level than normal semen.


Assuntos
Infertilidade Masculina/fisiopatologia , Sêmen/fisiologia , Ativador de Plasminogênio Tecidual/metabolismo , Adulto , Humanos , Infertilidade Masculina/etiologia , Masculino , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Valores de Referência , Fatores de Tempo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
10.
Hum Reprod ; 9(2): 293-302, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8027286

RESUMO

During in-vitro fertilization (IVF) procedures, human preimplantation embryos were classified into four grades according to their morphological appearance under light microscopy. The grade IV group included poor quality embryos. In our IVF programme, these embryos were never transferred or frozen, and were thus available for cytogenetic analysis. Cytogenetic analysis was performed on 411 grade IV embryos from 327 couples participating in the IVF programme. A total of 118 embryos were successfully karyotyped using at least one metaphase. Normal diploid chromosomes were found in only 12 embryos, containing a total of 19 metaphases. All others (90%) showed abnormal or aberrant chromosome complements; 48 were aneuploid and six cases of single chromatids were noted; 14 embryos (11.8%) contained haploid complements, while the remaining 44 exhibited mosaics (2n/3n, n/2n, n/3n) or fragmented chromosome sets. Also, several structural aberrations and rearrangements were observed. These results indicate that the large majority of grade IV human embryos are chromosomally abnormal. This confirms the morphological assessment of the poor quality of these embryos and demonstrates the uselessness of both the transfer and the cryopreservation of grade IV embryos.


Assuntos
Blastocisto/patologia , Aberrações Cromossômicas/patologia , Fertilização in vitro , Blastocisto/fisiologia , Transtornos Cromossômicos , Feminino , Humanos , Cariotipagem , Gravidez
12.
Hum Reprod ; 8(4): 604-8, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8501193

RESUMO

A simple and reliable R banding technique was developed for karyotyping mature human oocytes. The banding quality obtained is sufficient for the diagnosis of specific aneuploidies and the discrimination between whole chromosomes and separated chromatids. The ability to karyotype human oocytes accurately will facilitate study of the aetiology of chromosomal abnormalities in human concepti.


Assuntos
Bandeamento Cromossômico/métodos , Oócitos/fisiologia , Feminino , Humanos , Cariotipagem , Reprodutibilidade dos Testes , Fatores de Tempo
13.
Ann Genet ; 36(4): 200-5, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8166424

RESUMO

Three male patients with X-linked alpha-thalassemia/mental retardation (ATR-X) syndrome in a large French family are reported. Diagnosis was suspected on particular craniofacial dysmorphism associated with severe mental retardation and X-linked transmission. Hematological investigations, and in particular presence of Hb H inclusions in two of the boys, confirmed diagnosis. The clinical, hematological and radiological features are discussed in order to better define what appears to be a characteristic phenotype.


Assuntos
Ligação Genética , Deficiência Intelectual/genética , Cromossomo X , Talassemia alfa/genética , Pré-Escolar , Ossos Faciais/anormalidades , França , Testes Hematológicos , Humanos , Lactente , Deficiência Intelectual/sangue , Cariotipagem , Masculino , Linhagem , Crânio/anormalidades , Síndrome , Talassemia alfa/sangue
14.
Ann Genet ; 36(2): 94-9, 1993.
Artigo em Francês | MEDLINE | ID: mdl-8215225

RESUMO

A cytogenetic analysis was performed on a sample of 411 human grade IV embryos (i.e. poor morphological quality embryos, never transferred in our in vitro fertilization (IVF) pro Gram) in order to investigate the chromosomal status of these embryos. One hundred eighteen were successfully karyotyped from at least one metaphase. Only 10% displayed normal diploid metaphases. Aneuploidy was the most frequently observed abnormality, with a rate of 36.4%. Six cases of single chromatids were noted and 9 embryos showed structural aberrations. Polyploidy (from 3n to 7n) and haploidy were also observed, suggesting parthenogenetic activation, polyspermy or chromosomal duplication. Mosaicism constituted 6% of the abnormalities. Thirty embryos exhibited fragmented chromosome sets which might result from in vitro delayed fertilization.


Assuntos
Aberrações Cromossômicas , Embrião de Mamíferos/patologia , Fertilização in vitro , Humanos , Cariotipagem , Metáfase/genética
15.
Br J Obstet Gynaecol ; 100(1): 63-8, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8427841

RESUMO

OBJECTIVE: The effect of selective fetocide on the course of 61 multiple pregnancies. DESIGN: An observational study. SETTING: A tertiary centre. SUBJECTS: 61 women whose pregnancies included 37 triplets, 18 quadruplets, 5 quintuplets and 1 hepatuplet; 97% followed IVF or the induction of ovulation. The aim of the procedure in most cases was to obtain twins. INTERVENTIONS: Selective reduction was performed before 13 weeks gestation under general anaesthesia, using either a transcervical (n = 26) or transabdominal approach (n = 35). Fifty-four twins, 4 singletons and 3 triplets were obtained after the procedure. MAIN OUTCOME MEASURE: Preterm labour rate. RESULTS: The rate of unplanned fetal loss was 13% and was related to the number of suppressed embryos (P < 0.05). The preterm labour rate was 56.6%, the mean gestation at delivery was 35.6 weeks. Seven deliveries were before 32 weeks and led to all neonatal deaths. A comparison with published data suggested that fetal reduction reduced the rate of preterm labour in high multiple pregnancies; in 24 twin pregnancies obtained after reduction of triplets there was probably a gain of 2 weeks gestation. Severe growth retardation occurred in 13%. The perinatal mortality rate was 10.8%. CONCLUSIONS: Selective termination reduces but does not prevent early preterm labour. The procedure is of value in pregnancies with more than 3 fetuses and should be considered carefully for triplet pregnancies.


Assuntos
Aborto Induzido , Gravidez Múltipla , Adulto , Feminino , Fertilização in vitro , Morte Fetal , Humanos , Indução da Ovulação , Gravidez , Resultado da Gravidez
17.
J Med Genet ; 29(4): 259-61, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1583648

RESUMO

We report the first case of an interstitial deletion of the distal long arm of chromosome 4 (q31.22----q34.2). The major clinical features are described and compared to those of other published reports of del 4q, mainly those sharing a common deleted segment with the present case (both interstitial and terminal). This comparison suggests that the characteristic phenotype attributed to terminal deletions of 4q31----qter probably mainly results from loss of the segment q31----q33-34.


Assuntos
Anormalidades Múltiplas/genética , Deleção Cromossômica , Cromossomos Humanos Par 4 , Ossos Faciais/anormalidades , Feminino , Cardiopatias Congênitas/genética , Humanos , Lactente , Cariotipagem , Crânio/anormalidades
18.
Ann Chir Main Memb Super ; 11(5): 389-400, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1284021

RESUMO

The degree of severity of congenital deformities of the hand, as well as any coexisting congenital anomaly should be evaluated especially if there is a possibility of therapeutic termination of pregnancy. This may be relatively easy in the case of some major malformations which affect the neurological or intellectual capacity of the child. It is however more difficult in the presence of predominantly motor anomalies, and with distally based anomalies of the upper limb which may be amenable to later reconstructive surgery.


Assuntos
Braço/embriologia , Deformidades Congênitas da Mão/embriologia , Ultrassonografia Pré-Natal , Braço/anormalidades , Braço/diagnóstico por imagem , Aberrações Cromossômicas/diagnóstico por imagem , Aberrações Cromossômicas/embriologia , Transtornos Cromossômicos , Feminino , Mãos/diagnóstico por imagem , Mãos/embriologia , Deformidades Congênitas da Mão/diagnóstico por imagem , Humanos , Osteocondrodisplasias/diagnóstico por imagem , Osteocondrodisplasias/embriologia , Gravidez
19.
Ann Genet ; 35(2): 117-20, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1524409

RESUMO

It has been suggested that partial distal 2p2----2pter duplication causes a relatively well defined clinical syndrome, mostly as regards craniofacial dysmorphism, musculoskeletal and genitalia anomalies. Duplications covering a larger portion of 2p i.e. 2p12 or 2p13----2pter are however less documented. The authors report a new case of partial 2p13----2pter duplication which supplies further evidence for short life expectancy due to the large number of malformations in these partial duplications.


Assuntos
Anormalidades Múltiplas/genética , Aberrações Cromossômicas/genética , Cromossomos Humanos Par 2 , Aberrações dos Cromossomos Sexuais/genética , Translocação Genética/genética , Cromossomo X , Transtornos Cromossômicos , Feminino , Humanos , Recém-Nascido , Cariotipagem , Família Multigênica/genética , Gravidez , Síndrome
20.
J Perinat Med ; 20(2): 159-61, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1501060

RESUMO

Eighteen women were referred for fetal karyotyping because of advanced maternal age (over 38 years) later than 23 weeks' gestation. In order to obtain more rapid karyotypes, cordocentesis rather than amniocentesis was performed. All procedures were successful, leading to the obtention of normal karyotypes in all cases. No fetal incidents occurred and results were obtained more rapidly than by amniocentesis. We suggest the use of cordocentesis rather than amniocentesis in cases of late referral of women.


Assuntos
Amniocentese , Aberrações Cromossômicas/diagnóstico , Sangue Fetal/citologia , Cariotipagem , Adulto , Células Cultivadas , Transtornos Cromossômicos , Feminino , Idade Gestacional , Humanos , Linfócitos/ultraestrutura , Idade Materna , Gravidez , Gravidez de Alto Risco , Diagnóstico Pré-Natal
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