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Molecular Mechanisms of Growth Hormone in Ovarian Functions
Growth hormone (GH) has been used as a co-gonadotrophin in assisted reproduction, particularly in poor ovarian responders. The application of GH has been alleged to activate primordial follicles and improve oocyte quality, embryo quality, and steroidogenesis. However, the effects of GH on the live birth rate among women is controversial. Additionally, although the basic biological mechanisms that lead to the above clinical differences have been investigated, they are not yet well understood. The actions of GH are mediated by GH receptors (GHRs) or insulin-like growth factors (IGFs). GH regulates the vital signal transduction pathways that are involved in primordial follicular activation, steroidogenesis, and oocyte maturation.
29 Sep 2022
Placenta of Pregnancy Complicated by Gestational Diabetes Mellitus
Gestational diabetes mellitus (GDM), a glucose intolerance developing or first recognized during pregnancy, leads to a series of short- and long-term maternal and fetal complications, somehow related to placenta structural and functional changes. The placenta has a key role in correct fetal development. A series of factors are related to the correct functioning of the placenta as maternal and fetal blood flow, expression and function of receptors and transporters, and appropriate nutrients.
28 Sep 2022
Paraneoplastic Leukocytosis in Cervical Cancer
Tumor-associated leukocytosis has been associated with poor prognosis in cervical cancer. Leukemoid reaction (i.e., white blood cell count > 40,000/μL) is defined paraneoplastic (PLR) when it occurs in the presence of a cytokine-secreting tumor (CST) without neoplastic bone marrow infiltration. Cervical cancers displaying PLR represent a peculiar entity characterized by a rapidly progressive behavior typically associated with chemo-radioresistance.
30 Aug 2022
Polycystic Ovary Syndrome Physiopathology and Vitamin D Deficiency
Women with PCOS (polycystic ovary syndrome) are deficient in VD, particularly those with a higher weight. Hypovitaminosis is a risk factor for glucose intolerance, and reduced levels of VD is associated with insulin resistance and increased diabetes risk. Since women with PCOS and hirsutism seem to have lower levels of VD than women with PCOS without hirsutism, a correlation between VD deficiency and hyperandrogenism may be suggested. Interestingly, VD is crucial for many human physiological functions, including to counteract inflammation and oxidative stress. Some studies evaluated effects of VD supplementation on glucose homeostasis variables, hormonal status, lipid concentrations, and biomarkers of inflammation and oxidative stress among VD-deficient women. Moreover, VD has been shown to play a role in egg quality and fertility.
26 Aug 2022
Human placentation in a unique and complex process. It is associated with intensive adaptation in the maternal body, which allows the pregnancy to be maintained and to develop. Adaptation includes changes in the maternal circulation and pulmonary, secretory and immune system changes. These complex mechanisms, dependent on each other, are essential to allow the creation of the placenta and its functioning. Preeclampsia (PE) was the first pregnancy disorder whose etiopathogenesis was connected to abnormal placentation. In 1992, Christopher W. G. Redman proposed the two-stage hypothesis of PE development: earlier placental stage (deficient placentation) and later maternal symptoms (evolving from systemic vascular inflammation). Roberts and Redman assumed that factors inducing maternal endothelial dysfunction were the link between the two stages. Those factors had an angiogenic function and included vascular endothelial growth factor (VEGF) and placental growth factor (PlGF)—both with proangiogenic functions—and soluble decoy receptor for VEGF and PlGF (named soluble fms-like tyrosine kinase-1 or sFlt) and soluble endoglin (sEng)—with antiangiogenic functions. Nowadays, impaired placentation and disturbed maternal adaptation may lead to several pregnancy complications. In 2019, in a paper by Anne Cathrine Staff, they were called placental syndromes, as they all arise from impaired trophoblast invasion or trophoblast stress. They include pregnancy loss, fetal growth restriction (FGR), preeclampsia (PE), preterm delivery, premature rupture of membranes (PROM), placental abruption and intrauterine fetal demise.
25 Aug 2022
Glycosylated Antitumor Ether Lipids
Recurrent epithelial ovarian cancer (EOC) coincident with chemotherapy resistance remains the main contributor to patient mortality. There is an ongoing investigation to enhance patient progression-free and overall survival with novel chemotherapeutic delivery, such as the utilization of antiangiogenic medications, PARP inhibitors, or immune modulators. Glycosylated antitumor ether lipids (GAELs) are synthetic glycerolipids capable of killing established human epithelial cell lines from a wide variety of human cancers, including EOC cell lines representative of different EOC histotypes. Importantly, GAELs kill high-grade serous ovarian cancer (HGSOC) cells isolated from the ascites of chemotherapy-sensitive and chemotherapy-resistant patients grown as monolayers of spheroid cultures. In addition, GAELs were well tolerated by experimental animals (mice) and were capable of reducing tumor burden and blocking ascites formation in an OVCAR-3 xenograft model. Overall, GAELs show great promise as adjuvant therapy for EOC patients with or without chemotherapy resistance.
23 Aug 2022
Ovarian Drilling in Polycystic Ovary Syndrome Patients
Polycystic ovary syndrome (PCOS) is the leading cause of anovulatory infertility. Many pharmacological strategies have been applied for the induction of ovulation with a non-negligible rate of severe complications such as ovarian hyperstimulation syndrome and multiple pregnancies. Ovarian drilling (OD) is adopted as a second-line treatment, to be performed in case of medical therapy. Laparoscopic ovarian drilling (LOD), the contemporary version of ovarian wedge resection, is considered effective for gonadotropins in terms of live birth rates, but without the risks of iatrogenic complications in gonadotropin therapy. Its endocrinal effects are longer lasting and, after the accomplishment of this procedure, ovarian responsiveness to successive ovulation induction agents is enhanced. Traditional LOD, however, is burdened by the potential risks of iatrogenic adhesions and decreased ovarian reserve and, therefore, should only be considered in selected cases. To overcome these limits, novel tailored and mini-invasive approaches, which are still waiting for wide acceptance, have been introduced.
11 Aug 2022
Estro-Progestins and Pain Relief in Endometriosis
Endometriosis is a benign, hormone-responsive chronic disease that affects women of reproductive age; long-term treatment to balance satisfactory tolerability with clinical efficacy is necessary for these patients. The first-line therapy for endometriosis is predominantly medical treatment, in order to improve symptoms or prevent post-surgical disease recurrence. Multiple factors including age and women preference, pain severity, and endometriosis stage must be considered in the choice of the most suitable therapy. Estrogen-progestogins are generally used as first-line hormone therapies among different medical options currently effective for endometriosis management. Several studies have shown that they are able to improve pain symptoms in most patients, are well tolerated, and are inexpensive. Combined hormonal contraception treatment, administered cyclically or continuously, with different types of hormones and route of administration, results in clinically noticeable decrease in dysmenorrhea, noncyclic pelvic pain, dyspareunia, and recurrence rate after surgery, and also in quality of life improvement.
29 Jun 2022
Animal Models and Endometrioma-Related Infertility
Endometrioma (OMA) is the most common subtype of endometriosis, in which the endometriotic lesions are implanted in the ovary. Women with OMA are usually associated with infertility, presenting with reduced ovarian reserve, low oocyte quantity and quality, and poor fertility outcomes. However, the underlying pathological mechanisms in OMA-related infertility are still unclear. Due to the limitations and ethical issues of human studies in reproduction, animal models that recapitulate OMA characteristics and its related infertility are critical for mechanistic studies and subsequent drug development, preclinical testing, and clinical trials.
29 Jun 2022
Cervical Cancer and Treatment
The premalignancy of the uterine cervix is preventable and treatable if neoplasia is detected early. “Screen-and-treat” is a commonly adopted clinical management for precancerous lesions. In general, the standard curative options for precancers include large loop excision of the transformation zone (LLETZ) or loop electrosurgical excision procedure (LEEP), cryotherapy, and cold knife conization, while for locally advanced cervical cancer, hysterectomy, radiotherapy, chemotherapy, and radiotherapy with concurrent chemotherapy and immunotherapy are offered to the patients.
28 Jun 2022
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