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1.
Evol Med Public Health ; 10(1): 221-230, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35557512

RESUMO

Background and objectives: Hepatocellular carcinoma occurs frequently in prosimians, but the cause of these liver cancers in this group is unknown. Characterizing the genetic changes associated with hepatocellular carcinoma in prosimians may point to possible causes, treatments and methods of prevention, aiding conservation efforts that are particularly crucial to the survival of endangered lemurs. Although genomic studies of cancer in non-human primates have been hampered by a lack of tools, recent studies have demonstrated the efficacy of using human exome capture reagents across primates. Methodology: In this proof-of-principle study, we applied human exome capture reagents to tumor-normal pairs from five lemurs with hepatocellular carcinoma to characterize the mutational landscape of this disease in lemurs. Results: Several genes implicated in human hepatocellular carcinoma, including ARID1A, TP53 and CTNNB1, were mutated in multiple lemurs, and analysis of cancer driver genes mutated in these samples identified enrichment of genes involved with TP53 degradation and regulation. In addition to these similarities with human hepatocellular carcinoma, we also noted unique features, including six genes that contain mutations in all five lemurs. Interestingly, these genes are infrequently mutated in human hepatocellular carcinoma, suggesting potential differences in the etiology and/or progression of this cancer in lemurs and humans. Conclusions and implications: Collectively, this pilot study suggests that human exome capture reagents are a promising tool for genomic studies of cancer in lemurs and other non-human primates. Lay Summary: Hepatocellular carcinoma occurs frequently in prosimians, but the cause of these liver cancers is unknown. In this proof-of-principle study, we applied human DNA sequencing tools to tumor-normal pairs from five lemurs with hepatocellular carcinoma and compared the lemur mutation profiles to those of human hepatocellular carcinomas.

2.
G3 (Bethesda) ; 12(6)2022 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-35451464

RESUMO

By modeling the homoeologous gene losses that occurred in 50 genomes deriving from ten distinct polyploidy events, we show that the evolutionary forces acting on polyploids are remarkably similar, regardless of whether they occur in flowering plants, ciliates, fishes, or yeasts. We show that many of the events show a relative rate of duplicate gene loss before the first postpolyploidy speciation that is significantly higher than in later phases of their evolution. The relatively weak selective constraint experienced by the single-copy genes these losses produced leads us to suggest that most of the purely selectively neutral duplicate gene losses occur in the immediate postpolyploid period. Nearly all of the events show strong evidence of biases in the duplicate losses, consistent with them being allopolyploidies, with 2 distinct progenitors contributing to the modern species. We also find ongoing and extensive reciprocal gene losses (alternative losses of duplicated ancestral genes) between these genomes. With the exception of a handful of closely related taxa, all of these polyploid organisms are separated from each other by tens to thousands of reciprocal gene losses. As a result, it is very unlikely that viable diploid hybrid species could form between these taxa, since matings between such hybrids would tend to produce offspring lacking essential genes. It is, therefore, possible that the relatively high frequency of recurrent polyploidies in some lineages may be due to the ability of new polyploidies to bypass reciprocal gene loss barriers.


Assuntos
Eucariotos , Evolução Molecular , Diploide , Humanos , Filogenia , Poliploidia
3.
J Assist Reprod Genet ; 37(3): 611-617, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31897845

RESUMO

PURPOSE: To assess whether GnRH agonist trigger impacts the implantation potential of euploid embryos. METHODS: Retrospective cohort study done at an academic IVF center evaluating frozen-thawed embryo transfer (FET) cycles in which single-euploid blastocysts were transferred between 2014 and 2019. All embryos were generated in an IVF cycle which used GnRHa or hCG trigger and then were transferred in a programmed or natural FET cycle. Only the first FET cycle was included for each patient. Primary outcome was ongoing pregnancy rate or live birth rate (OPR/LBR). Secondary outcomes were implantation rate (IR), clinical pregnancy rate (CPR), clinical loss rate (CLR), and multiple pregnancy rate (MPR). Logistic regression was performed to control for confounding variables. A p value of < 0.05 was considered statistically significant. RESULTS: Two hundred sixty-three FET cycles were included for analysis (GnRHa = 145; hCG = 118). The GnRHa group was significantly younger (35.2 vs. 37.5 years) and had higher AMH values (4.50 ng/ml vs. 2.03 ng/ml) than the hCG group, respectively (p < 0.05). There was no significant difference in OPR/LBR (64.1% (93/145) vs. 65.3% (77/118); p = 0.90) between the GnRHa and hCG groups, respectively. There was also no significant difference in IR, CPR, CLR, or MPR between groups. After controlling for confounding variables, the adjusted odds ratio for OPR/LBR was 0.941 (95% CI, 0.534-1.658); p = 0.83) comparing GnRHa to hCG. Pregnancy outcomes did not significantly differ when groups were stratified by age (< 35 vs. > 35 years old). CONCLUSIONS: Our findings confirm that euploid embryos created after hCG or GnRHa trigger have the same potential for pregnancy.


Assuntos
Blastocisto/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/administração & dosagem , Oogênese/efeitos dos fármacos , Diagnóstico Pré-Implantação , Adulto , Coeficiente de Natalidade , Blastocisto/metabolismo , Implantação do Embrião/efeitos dos fármacos , Transferência Embrionária/métodos , Feminino , Fertilização in vitro/métodos , Hormônio Liberador de Gonadotropina/agonistas , Humanos , Técnicas de Maturação in Vitro de Oócitos/métodos , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , Indução da Ovulação/métodos , Gravidez , Resultado da Gravidez
4.
Mol Biol Evol ; 37(1): 11-17, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31688937

RESUMO

Despite a considerable expenditure of time and resources and significant advances in experimental models of disease, cancer research continues to suffer from extremely low success rates in translating preclinical discoveries into clinical practice. The continued failure of cancer drug development, particularly late in the course of human testing, not only impacts patient outcomes, but also drives up the cost for those therapies that do succeed. It is clear that a paradigm shift is necessary if improvements in this process are to occur. One promising direction for increasing translational success is comparative oncology-the study of cancer across species, often involving veterinary patients that develop naturally-occurring cancers. Comparative oncology leverages the power of cross-species analyses to understand the fundamental drivers of cancer protective mechanisms, as well as factors contributing to cancer initiation and progression. Clinical trials in veterinary patients with cancer provide an opportunity to evaluate novel therapeutics in a setting that recapitulates many of the key features of human cancers, including genomic aberrations that underly tumor development, response and resistance to treatment, and the presence of comorbidities that can affect outcomes. With a concerted effort from basic scientists, human physicians and veterinarians, comparative oncology has the potential to enhance the cost-effectiveness and efficiency of pipelines for cancer drug discovery and other cancer treatments.


Assuntos
Descoberta de Drogas , Neoplasias/veterinária , Animais , Humanos , Neoplasias/tratamento farmacológico
5.
Fertil Steril ; 112(3): 534-544, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31227286

RESUMO

OBJECTIVE: To characterize corpora lutea (CL) function after gonadotropin-releasing hormone agonist (GnRHa) trigger with the use of adjuvant human chorionic gonadotropin (hCG). DESIGN: Secondary analysis of serum from prospective randomized clinical trial. SETTING: University-based fertility center. PATIENT(S): Women under 40 years of age at risk of ovarian hyperstimulation syndrome (OHSS) with serum E2 level <4,000 pg/mL. INTERVENTIONS(S): All subjects underwent ovarian stimulation with the use of a GnRH antagonist protocol. Within a larger study, subjects were randomized to receive 1,000 IU hCG at the time of GnRHa trigger and placebo at the time of vaginal oocyte retrieval (VOR) or placebo at the time of GnRHa trigger and 1,500 IU hCG at the time of VOR. MAIN OUTCOME MEASURE(S): Luteal phase and early pregnancy curves of serum prorenin and 17α-hydroxyprogesterone (17OH-P). RESULT(S): Thirty subjects enrolled in this secondary analysis. Serum 17OH-P peaked in the early luteal phase, 5 days after GnRHa trigger, with a nadir in the mid-luteal phase 9 days after trigger. Serum prorenin peaked in the luteal phase 2 days after GnRHa trigger, independently from adjuvant hCG timing, and reached a nadir at 9 days after trigger. CL function appears higher when adjuvant hCG is given at VOR compared with adjuvant hCG given at the time of trigger. CONCLUSION(S): CL function, as interpreted by proxy measures of serum prorenin and 17OH-P with pregnancy, continues despite GnRHa trigger. Both options for adjuvant hCG timing are sufficient for CL rescue and successful pregnancy, so the potential for OHSS risk with increased CL activity after hCG at VOR should be considered. CLINICAL TRIAL REGISTRATION NUMBER: NCT01815138.


Assuntos
17-alfa-Hidroxiprogesterona/sangue , Gonadotropina Coriônica/administração & dosagem , Corpo Lúteo/metabolismo , Fertilização in vitro/métodos , Hormônio Liberador de Gonadotropina/agonistas , Renina/sangue , Adulto , Biomarcadores/sangue , Corpo Lúteo/efeitos dos fármacos , Método Duplo-Cego , Feminino , Humanos , Infertilidade Feminina/sangue , Infertilidade Feminina/epidemiologia , Infertilidade Feminina/terapia , Nascido Vivo/epidemiologia , Gravidez , Estudos Prospectivos
6.
Fertil Steril ; 112(2): 258-265, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31103285

RESUMO

OBJECTIVE: To evaluate differences in euploidy rates between IVF cycles triggered with either GnRH agonist (GnRHa) or hCG. DESIGN: Retrospective cohort study. SETTING: University-affiliated fertility center. PATIENT(S): A total of 366 patients performing 539 IVF cycles utilizing preimplantation genetic testing for aneuploidy (PGT-A). INTERVENTION(S): Gonadotropin-releasing hormone agonist or hCG trigger of oocyte maturation during IVF cycles. MAIN OUTCOME MEASURE(S): Rate of euploid embryos. RESULT(S): Patients in the GnRHa trigger arm were younger, with a lower body mass index and higher antimüllerian hormone level, and they had a higher number of oocytes retrieved and embryos biopsied. Euploid rate per embryo biopsied was higher after GnRHa trigger than after hCG trigger (37.8% ± 2.1% vs. 30.3% ± 1.8%), but multivariate regression analysis controlling for potential confounding factors did not show any differences between the two groups. Moreover, the euploid rate per oocyte retrieved was not significantly different overall (GnRHa vs. hCG: 33.9% ± 2.2% vs. 28.0% ± 1.9%). The anticipated decline in the rate of euploid embryos per oocyte retrieved went from 15.8% ± 1.2% for age <35 years to 4.3% ± 0.9% for patients aged ≥41 years. There were no significant differences between the two groups after stratifying by age and controlling for PGT-A testing modality. CONCLUSION(S): Both GnRHa and hCG trigger result in comparable euploid rates. Trigger with GnRHa should therefore be considered a valid option for trigger modality in freeze-all PGT-A cycles, in view of its demonstrated effectiveness and known safety enhancement.


Assuntos
Gonadotropina Coriônica/uso terapêutico , Fármacos para a Fertilidade Feminina/uso terapêutico , Testes Genéticos/estatística & dados numéricos , Hormônio Liberador de Gonadotropina/uso terapêutico , Indução da Ovulação/métodos , Ploidias , Diagnóstico Pré-Implantação/estatística & dados numéricos , Adulto , Aneuploidia , Feminino , Fertilização in vitro/estatística & dados numéricos , Humanos , Infertilidade Feminina/epidemiologia , Infertilidade Feminina/genética , Infertilidade Feminina/terapia , Ciclo Menstrual/efeitos dos fármacos , Oogênese/efeitos dos fármacos , Oogênese/genética , Indução da Ovulação/efeitos adversos , Indução da Ovulação/estatística & dados numéricos , Gravidez , Estudos Retrospectivos
7.
J Assist Reprod Genet ; 35(4): 669-675, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29297113

RESUMO

PURPOSE: The aim of this study is to analyze clinical pregnancy rates (CPR) and ongoing pregnancy rates (OPR) for frozen embryo transfers (FET) performed with blastocysts in the cycle immediately after GnRH agonist (GnRHa) versus human chorionic gonadotropin (hCG) triggers, with outcomes of delayed FET for comparison. METHODS: Retrospective cohort study at a university-affiliated in vitro fertilization (IVF) clinic, including patients undergoing IVF between 2013-16 with a blastocyst FET performed within two menstrual cycles of a previous stimulation cycle and vaginal oocyte retrieval (VOR). FETs included programmed and natural endometrial preparation. Outcome measures were clinical and ongoing pregnancy rates. RESULTS: CPR and OPR for 344 FET cycles were similar when comparing immediate and delayed transfer overall (crude CPR 67.5 versus 76.5%, p = 0.11; OPR 57.5 versus 66.7%, p = 0.13), and after stratifying by cycles following hCG trigger (OPR 62.5 versus 66.3%, p = 0.61) and GnRHa trigger (OPR 55.6 versus 64.5%, p = 0.17). When considering a number of predictors for OPR, an adjusted odds ratio (OR) of 1.74 [95% CI 1.00-3.03] approached significance in favor of delayed FET. CONCLUSIONS: Regardless of trigger modality, patients can be reassured that pregnancy rates with FET are high in immediate and delayed cycles. However, our study suggests a potential benefit in delaying a cycle before proceeding with FET.


Assuntos
Gonadotropina Coriônica/administração & dosagem , Criopreservação , Transferência Embrionária/métodos , Fertilização in vitro/métodos , Hormônio Liberador de Gonadotropina/agonistas , Recuperação de Oócitos/métodos , Oócitos/crescimento & desenvolvimento , Adolescente , Adulto , Feminino , Congelamento , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/análogos & derivados , Humanos , Ciclo Menstrual , Oócitos/efeitos dos fármacos , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Adulto Jovem
8.
Biol Reprod ; 92(1): 25, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25411389

RESUMO

Dynamic reciprocity (DR) refers to the ongoing, bidirectional interaction between cells and their microenvironment, specifically the extracellular matrix (ECM). The continuous remodeling of the ECM exerts mechanical force on cells and modifies biochemical mediators near the cell membrane, thereby initiating cell-signaling cascades that produce changes in gene expression and cell behavior. Cellular changes, in turn, affect the composition and organization of ECM components. These continuous interactions are the fundamental principle behind DR, and its critical role throughout development and adult tissue homeostasis has been extensively investigated. While DR in the mammary gland has been well described, we provide direct evidence that similar dynamic interactions occur in other areas of reproductive biology as well. In order to establish the importance of DR in the adaptive functioning of the female reproductive tract, we present our most current understanding of DR in reproductive tissues, exploring the mammary gland, ovary, and uterus. In addition to explaining normal physiological function, investigating DR may shed new light into pathologic processes that occur in these tissues and provide an exciting opportunity for novel therapeutic intervention.


Assuntos
Comunicação Celular/fisiologia , Microambiente Celular/fisiologia , Reprodução/fisiologia , Adulto , Animais , Matriz Extracelular/fisiologia , Feminino , Humanos , Mecanotransdução Celular/fisiologia , Ovário/citologia , Ovário/fisiologia , Útero/citologia , Útero/fisiologia
9.
J Clin Endocrinol Metab ; 93(10): 4065-74, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18664535

RESUMO

CONTEXT: Elevated glucose levels impair islet function and survival, and it has been proposed that intraislet expression of IL-1beta contributes to glucotoxicity. OBJECTIVE: The objective was to investigate IL-1beta mRNA expression in near-pure beta-cells of patients with type 2 diabetes (T2DM) and study the regulation of IL-1beta by glucose in isolated human islets. METHODS: Laser capture microdissection was performed to isolate beta-cells from pancreas sections of 10 type 2 diabetic donors and nine controls, and IL-1beta mRNA expression was analyzed using gene arrays and PCR. Cultured human islets and fluorescence-activated cell sorter-purified human beta-cells were used to study the regulation of IL-1beta expression by glucose and IL-1beta. RESULTS: Gene array analysis of RNA from beta-cells of individuals with T2DM revealed increased expression of IL-1beta mRNA. Real-time PCR confirmed increased IL-1beta expression in six of 10 T2DM samples, with minimal or no expression in nine control samples. In cultured human islets, IL-1beta mRNA and protein expression was induced by high glucose and IL-1beta autostimulation and decreased by the IL-1 receptor antagonist IL-1Ra. The glucose response was negatively correlated with basal IL-1beta expression levels. Autostimulation was transient and nuclear factor-kappaB dependent. Glucose-induced IL-1beta was biologically active and stimulated IL-8 release. Low picogram per milliliter concentrations of IL-1beta up-regulated inflammatory factors IL-8 and IL-6. CONCLUSION: Evidence that IL-1beta mRNA expression is up-regulated in beta-cells of patients with T2DM is presented, and glucose-promoted IL-1beta autostimulation may be a possible contributor.


Assuntos
Comunicação Autócrina/fisiologia , Diabetes Mellitus Tipo 2/genética , Glucose/farmacologia , Células Secretoras de Insulina/metabolismo , Interleucina-1beta/genética , Ilhotas Pancreáticas/efeitos dos fármacos , Comunicação Autócrina/efeitos dos fármacos , Comunicação Autócrina/genética , Células Cultivadas , Diabetes Mellitus Tipo 2/metabolismo , Perfilação da Expressão Gênica , Humanos , Interleucina-1beta/metabolismo , Interleucina-1beta/farmacologia , Interleucina-6/genética , Interleucina-8/genética , Ilhotas Pancreáticas/metabolismo , NF-kappa B/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/metabolismo , Regulação para Cima/efeitos dos fármacos
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