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Stephen S Tobe - One of the best experts on this subject based on the ideXlab platform.
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sequencing and validation of housekeeping genes for quantitative real time pcr during the gonadotrophic cycle of diploptera punctata
BMC Research Notes, 2013Co-Authors: Elisabeth Marchal, Ekaterina F Hult, Juan Huang, Stephen S TobeAbstract:Quantitative RT-PCR (q-RT-PCR) is a powerful tool that allows for the large scale analysis of small changes in gene expression. Accurate and reliable results depend on the use of stable reference genes for normalization. However, the expression of some widely used housekeeping genes can vary under different experimental setups. To our knowledge, no validation studies have been reported for reference genes in cockroaches. The aim of the current study is the identification and validation of a set of eight housekeeping genes during the first gonadotrophic cycle of the cockroach, Diploptera punctata. This study made use of two different algorithms (geNorm and Normfinder) to evaluate the stability of gene expression. Candidate housekeeping genes were sequenced: β-actin (Actin), elongation factor 1 alpha (EF1a), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), armadillo (Arm), ribosomal protein L32 (RpL32), succinate dehydrogenase (SDHa), annexin IX (AnnIX) and α-tubulin (Tub). The expression of these eight genes was analyzed in corpora allata (CA) and ovaries of adult female D. punctata. Both geNorm, as well as Normfinder characterized SDHa, EF1a and Arm as being the most stably expressed in the corpora allata. In the Ovary, the geNorm calculation showed Tub, EF1a and RpL32 to be most stable, whereas Normfinder identified Tub, EF1a and Arm as the best. In Ovary, the least stable gene was Actin, challenging its usefulness in normalization. As a proof of principle, the expression of follicle cell protein 3c and CYP15A1 was monitored during the first gonadotrophic cycle. Arm and EF1a form the most stably expressed combination of two reference genes out of the eight candidates that were tested in the corpora allata. Our results show that the combined use of Tub, EF1a and RpL32 ensures an accurate normalization of gene expression levels in Ovary of D. punctata. Our study has indicated that neither Actin nor AnnIX should be used for normalization of transcript levels when studying the first gonadotrophic cycle in CA or Ovary of D. punctata. The results stress the necessity for validation of reference genes in q-RT-PCR studies in cockroaches.
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Sequencing and validation of housekeeping genes for quantitative real-time PCR during the gonadotrophic cycle of Diploptera punctata
BMC Research Notes, 2013Co-Authors: Elisabeth Marchal, Ekaterina F Hult, Juan Huang, Stephen S TobeAbstract:Background Quantitative RT-PCR (q-RT-PCR) is a powerful tool that allows for the large scale analysis of small changes in gene expression. Accurate and reliable results depend on the use of stable reference genes for normalization. However, the expression of some widely used housekeeping genes can vary under different experimental setups. To our knowledge, no validation studies have been reported for reference genes in cockroaches. The aim of the current study is the identification and validation of a set of eight housekeeping genes during the first gonadotrophic cycle of the cockroach, Diploptera punctata . This study made use of two different algorithms (geNorm and Normfinder) to evaluate the stability of gene expression. Results Candidate housekeeping genes were sequenced: β-actin ( Actin ), elongation factor 1 alpha ( EF1a ), glyceraldehyde-3-phosphate dehydrogenase ( GAPDH ), armadillo ( Arm ), ribosomal protein L32 ( RpL32 ), succinate dehydrogenase ( SDHa ), annexin IX ( AnnIX ) and α-tubulin ( Tub ). The expression of these eight genes was analyzed in corpora allata (CA) and ovaries of adult female D. punctata . Both geNorm, as well as Normfinder characterized SDHa , EF1a and Arm as being the most stably expressed in the corpora allata. In the Ovary, the geNorm calculation showed Tub , EF1a and RpL32 to be most stable, whereas Normfinder identified Tub , EF1a and Arm as the best. In Ovary, the least stable gene was Actin , challenging its usefulness in normalization. As a proof of principle, the expression of follicle cell protein 3c and CYP15A1 was monitored during the first gonadotrophic cycle. Conclusion Arm and EF1a form the most stably expressed combination of two reference genes out of the eight candidates that were tested in the corpora allata. Our results show that the combined use of Tub , EF1a and RpL32 ensures an accurate normalization of gene expression levels in Ovary of D. punctata. Our study has indicated that neither Actin nor AnnIX should be used for normalization of transcript levels when studying the first gonadotrophic cycle in CA or Ovary of D. punctata . The results stress the necessity for validation of reference genes in q-RT-PCR studies in cockroaches.
Stephen Franks - One of the best experts on this subject based on the ideXlab platform.
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obesity and polycystic Ovary syndrome
Clinical Endocrinology, 2006Co-Authors: Thomas M Barber, Mark I Mccarthy, John Wass, Stephen FranksAbstract:The aetiology of Polycystic Ovary Syndrome (PCOS) is complex and multifactorial. There is much evidence, however, to suggest that adipose tissue plays an important role in the development and maintenance of PCOS pathology. There is a close correlation between adiposity and symptom severity in women with PCOS, and even modest reductions in weight generally translate into significant improvements in menstrual regularity, fertility and hyperandrogenic features. This review article considers the various mechanisms that might underlie this link between excess adiposity and PCOS - including the effects of differential insulin sensitivity, abnormal steroid hormone metabolism and adipocytokine secretion. Greater attention to the therapeutic options available to reduce the impact of excess adiposity on ovarian and metabolic function is essential to the management of PCOS.
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polycystic Ovary syndrome
Medicine, 2001Co-Authors: Stephen FranksAbstract:Abstract Polycystic Ovary syndrome (PCOS) is the most common endocrine disorder in women. It typically presents with symptoms of anovulation associated with clinical and/or biochemical evidence of androgen excess, although its spectrum of presentation includes women with hyperandrogenism who have regular periods. It is the most common cause of anovulatory infertility, and is now recognized as a major risk factor for the development of type 2 diabetes mellitus. Its aetiology remains unclear, but both genetic and environmental factors are involved. Typical biochemical features are raised serum concentrations of testosterone and luteinizing hormone, particularly in anovulatory women. The diagnosis is made primarily on clinical criteria. A finding of raised serum testosterone and/or luteinizing hormone complements the clinical diagnosis. In obese women, an oral glucose tolerance test should be undertaken to detect impaired glucose tolerance. Management of PCOS includes treatment of infertility, menstrual regulation in women who do not desire pregnancy and treatment of associated symptoms of hyperandrogenism. Another important aspect of management is the introduction of diet and lifestyle changes for overweight and obese women with PCOS; this improves fertility and also helps prevent the possible long-term consequences of the metabolic disturbance characteristic of anovulatory women with PCOS.
Abubaker Elnashar - One of the best experts on this subject based on the ideXlab platform.
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Treatment options for polycystic Ovary syndrome
International Journal of Women's Health, 2011Co-Authors: Ahmed Badawy, Abubaker ElnasharAbstract:Polycystic Ovary syndrome (PCOS) is the most common endocrine disorder in women. The clinical manifestation of PCOS varies from a mild menstrual disorder to severe disturbance of reproductive and metabolic functions. Management of women with PCOS depends on the symptoms. These could be ovulatory dysfunction-related infertility, menstrual disorders, or androgen-related symptoms. Weight loss improves the endocrine profile and increases the likelihood of ovulation and pregnancy. Normalization of menstrual cycles and ovulation could occur with modest weight loss as little as 5% of the initial weight. The treatment of obesity includes modifications in lifestyle (diet and exercise) and medical and surgical treatment. In PCOS, anovulation relates to low follicle-stimulating hormone concentrations and the arrest of antral follicle growth in the final stages of maturation. This can be treated with medications such as clomiphene citrate, tamoxifen, aromatase inhibitors, metformin, glucocorticoids, or gonadotropins or surgically by laparoscopic ovarian drilling. In vitro fertilization will remain the last option to achieve pregnancy when others fail. Chronic anovulation over a long period of time is also associated with an increased risk of endometrial hyperplasia and carcinoma, which should be seriously investigated and treated. There are androgenic symptoms that will vary from patient to patient, such as hirsutism, acne, and/or alopecia. These are troublesome presentations to the patients and require adequate treatment. Alternative medicine has been emerging as one of the commonly practiced medicines for different health problems, including PCOS. This review underlines the contribution to the treatment of different symptoms.
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Treatment options for polycystic Ovary syndrome
Dove Medical Press, 2011Co-Authors: Ahmed Badawy, Abubaker ElnasharAbstract:Ahmed Badawy1 Abubaker Elnashar21Department of Obstetrics and Gynecology, Mansoura University, Mansoura, Egypt; 2Department of Obstetrics and Gynecology, Benha University, Benha, EgyptAbstract: Polycystic Ovary syndrome (PCOS) is the most common endocrine disorder in women. The clinical manifestation of PCOS varies from a mild menstrual disorder to severe disturbance of reproductive and metabolic functions. Management of women with PCOS depends on the symptoms. These could be ovulatory dysfunction-related infertility, menstrual disorders, or androgen-related symptoms. Weight loss improves the endocrine profile and increases the likelihood of ovulation and pregnancy. Normalization of menstrual cycles and ovulation could occur with modest weight loss as little as 5% of the initial weight. The treatment of obesity includes modifications in lifestyle (diet and exercise) and medical and surgical treatment. In PCOS, anovulation relates to low follicle-stimulating hormone concentrations and the arrest of antral follicle growth in the final stages of maturation. This can be treated with medications such as clomiphene citrate, tamoxifen, aromatase inhibitors, metformin, glucocorticoids, or gonadotropins or surgically by laparoscopic ovarian drilling. In vitro fertilization will remain the last option to achieve pregnancy when others fail. Chronic anovulation over a long period of time is also associated with an increased risk of endometrial hyperplasia and carcinoma, which should be seriously investigated and treated. There are androgenic symptoms that will vary from patient to patient, such as hirsutism, acne, and/or alopecia. These are troublesome presentations to the patients and require adequate treatment. Alternative medicine has been emerging as one of the commonly practiced medicines for different health problems, including PCOS. This review underlines the contribution to the treatment of different symptoms.Keywords: treatment, polycystic Ovary syndrome 
Elisabeth Marchal - One of the best experts on this subject based on the ideXlab platform.
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sequencing and validation of housekeeping genes for quantitative real time pcr during the gonadotrophic cycle of diploptera punctata
BMC Research Notes, 2013Co-Authors: Elisabeth Marchal, Ekaterina F Hult, Juan Huang, Stephen S TobeAbstract:Quantitative RT-PCR (q-RT-PCR) is a powerful tool that allows for the large scale analysis of small changes in gene expression. Accurate and reliable results depend on the use of stable reference genes for normalization. However, the expression of some widely used housekeeping genes can vary under different experimental setups. To our knowledge, no validation studies have been reported for reference genes in cockroaches. The aim of the current study is the identification and validation of a set of eight housekeeping genes during the first gonadotrophic cycle of the cockroach, Diploptera punctata. This study made use of two different algorithms (geNorm and Normfinder) to evaluate the stability of gene expression. Candidate housekeeping genes were sequenced: β-actin (Actin), elongation factor 1 alpha (EF1a), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), armadillo (Arm), ribosomal protein L32 (RpL32), succinate dehydrogenase (SDHa), annexin IX (AnnIX) and α-tubulin (Tub). The expression of these eight genes was analyzed in corpora allata (CA) and ovaries of adult female D. punctata. Both geNorm, as well as Normfinder characterized SDHa, EF1a and Arm as being the most stably expressed in the corpora allata. In the Ovary, the geNorm calculation showed Tub, EF1a and RpL32 to be most stable, whereas Normfinder identified Tub, EF1a and Arm as the best. In Ovary, the least stable gene was Actin, challenging its usefulness in normalization. As a proof of principle, the expression of follicle cell protein 3c and CYP15A1 was monitored during the first gonadotrophic cycle. Arm and EF1a form the most stably expressed combination of two reference genes out of the eight candidates that were tested in the corpora allata. Our results show that the combined use of Tub, EF1a and RpL32 ensures an accurate normalization of gene expression levels in Ovary of D. punctata. Our study has indicated that neither Actin nor AnnIX should be used for normalization of transcript levels when studying the first gonadotrophic cycle in CA or Ovary of D. punctata. The results stress the necessity for validation of reference genes in q-RT-PCR studies in cockroaches.
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Sequencing and validation of housekeeping genes for quantitative real-time PCR during the gonadotrophic cycle of Diploptera punctata
BMC Research Notes, 2013Co-Authors: Elisabeth Marchal, Ekaterina F Hult, Juan Huang, Stephen S TobeAbstract:Background Quantitative RT-PCR (q-RT-PCR) is a powerful tool that allows for the large scale analysis of small changes in gene expression. Accurate and reliable results depend on the use of stable reference genes for normalization. However, the expression of some widely used housekeeping genes can vary under different experimental setups. To our knowledge, no validation studies have been reported for reference genes in cockroaches. The aim of the current study is the identification and validation of a set of eight housekeeping genes during the first gonadotrophic cycle of the cockroach, Diploptera punctata . This study made use of two different algorithms (geNorm and Normfinder) to evaluate the stability of gene expression. Results Candidate housekeeping genes were sequenced: β-actin ( Actin ), elongation factor 1 alpha ( EF1a ), glyceraldehyde-3-phosphate dehydrogenase ( GAPDH ), armadillo ( Arm ), ribosomal protein L32 ( RpL32 ), succinate dehydrogenase ( SDHa ), annexin IX ( AnnIX ) and α-tubulin ( Tub ). The expression of these eight genes was analyzed in corpora allata (CA) and ovaries of adult female D. punctata . Both geNorm, as well as Normfinder characterized SDHa , EF1a and Arm as being the most stably expressed in the corpora allata. In the Ovary, the geNorm calculation showed Tub , EF1a and RpL32 to be most stable, whereas Normfinder identified Tub , EF1a and Arm as the best. In Ovary, the least stable gene was Actin , challenging its usefulness in normalization. As a proof of principle, the expression of follicle cell protein 3c and CYP15A1 was monitored during the first gonadotrophic cycle. Conclusion Arm and EF1a form the most stably expressed combination of two reference genes out of the eight candidates that were tested in the corpora allata. Our results show that the combined use of Tub , EF1a and RpL32 ensures an accurate normalization of gene expression levels in Ovary of D. punctata. Our study has indicated that neither Actin nor AnnIX should be used for normalization of transcript levels when studying the first gonadotrophic cycle in CA or Ovary of D. punctata . The results stress the necessity for validation of reference genes in q-RT-PCR studies in cockroaches.
Stephen A Cannistra - One of the best experts on this subject based on the ideXlab platform.
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granulosa cell tumor of the Ovary
Journal of Clinical Oncology, 2003Co-Authors: Susan T Schumer, Stephen A CannistraAbstract:Adult granulosa cell tumor (GCT) of the Ovary is oftentimes a hormonally active, stromal cell neoplasm that is distinguished by its ability to secrete sex steroids such as estrogen. Patients may present with vaginal bleeding caused by endometrial hyperplasia or uterine cancer as a result of prolonged exposure to tumor-derived estrogen. In addition, GCT is a vascular tumor that may occasionally rupture and result in abdominal pain, hemoperitoneum, and hypotension, mimicking an ectopic pregnancy in younger patients. GCT is usually associated with a mass on pelvic examination that is subsequently confirmed on ultrasonography. Surgery is required for definitive tissue diagnosis, staging, and tumor debulking. In older women, a total abdominal hysterectomy and bilateral salpingooophorectomy are typically performed. In women of childbearing age, a more conservative unilateral salpingo-oophorectomy may be performed, assuming that careful staging reveals that the disease has not extended outside of the involved ov...
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granulosa cell tumor of the Ovary
Journal of Clinical Oncology, 2003Co-Authors: Susan Schumer, Stephen A CannistraAbstract:Adult granulosa cell tumor (GCT) of the Ovary is oftentimes a hormonally active, stromal cell neoplasm that is distinguished by its ability to secrete sex steroids such as estrogen. Patients may present with vaginal bleeding caused by endometrial hyperplasia or uterine cancer as a result of prolonged exposure to tumor-derived estrogen. In addition, GCT is a vascular tumor that may occasionally rupture and result in abdominal pain, hemoperitoneum, and hypotension, mimicking an ectopic pregnancy in younger patients. GCT is usually associated with a mass on pelvic examination that is subsequently confirmed on ultrasonography. Surgery is required for definitive tissue diagnosis, staging, and tumor debulking. In older women, a total abdominal hysterectomy and bilateral salpingooophorectomy are typically performed. In women of childbearing age, a more conservative unilateral salpingo-oophorectomy may be performed, assuming that careful staging reveals that the disease has not extended outside of the involved Ovary and that a concomitant uterine cancer has been excluded. Survival of patients with GCT is generally excellent because most patients present with early-stage disease, although certain high-risk patient groups may be identified. Stage is the most important prognostic factor, with a higher risk of relapse being associated with stages II through IV disease. In addition, patients with stage I disease associated with features such as large tumor size, high mitotic index, or tumor rupture may also be at higher risk in some series. The value of postoperative adjuvant therapy for high-risk patients has not been investigated by prospective randomized trials, which are difficult to perform because of the rarity of this tumor. Nonetheless, the use of adjuvant chemotherapy or radiation has sometimes been associated with prolonged disease-free survival in patients with high-risk features. Because of the propensity of GCT to recur years after initial diagnosis, prolonged surveillance with serial physical examination and serum tumor markers such as estradiol and inhibin is reasonable.
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cancer of the Ovary
The New England Journal of Medicine, 1993Co-Authors: Stephen A CannistraAbstract:Patients with ovarian cancer usually present with advanced disease, and the disease is generally managed with surgical resection followed by platinum-based chemotherapy. Recent chemotherapeutic advances have led to improved survival, and a better understanding of genetic risk factors has permitted a tailored approach to preventive strategies, such as bilateral salpingo-oophorectomy in selected women. This review describes the clinical features of ovarian cancer and recent advances in postoperative management.