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1.
JAMA Neurol ; 77(5): 582-592, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32065623

RESUMEN

Importance: Many patients with generalized myasthenia gravis (gMG) have substantial clinical disability, persistent disease burden, and adverse effects attributable to chronic immunosuppression. Therefore, there is a significant need for targeted, well-tolerated therapies with the potential to improve disease control and enhance quality of life. Objective: To evaluate the clinical effects of zilucoplan, a subcutaneously (SC) self-administered macrocyclic peptide inhibitor of complement component 5, in a broad population of patients with moderate to severe gMG. Design, Setting, and Participants: This randomized, double-blind, placebo-controlled phase 2 clinical trial at 25 study sites across North America recruited participants between December 2017 and August 2018. Fifty-seven patients were screened, of whom 12 did not meet inclusion criteria and 1 was lost to follow-up after randomization but before receiving study drug, resulting in a total of 44 acetylcholine receptor autoantibody (AChR-Ab)-positive patients with gMG with baseline Quantitative Myasthenia Gravis (QMG) scores of at least 12, regardless of treatment history. Interventions: Patients were randomized 1:1:1 to a daily SC self-injection of placebo, 0.1-mg/kg zilucoplan, or 0.3-mg/kg zilucoplan for 12 weeks. Main Outcomes and Measures: The primary and key secondary end points were the change from baseline to week 12 in QMG and MG Activities of Daily Living scores, respectively. Significance testing was prespecified at a 1-sided α of .10. Safety and tolerability were also assessed. Results: The study of 44 patients was well balanced across the 3 treatment arms with respect to key demographic and disease-specific variables. The mean age of patients across all 3 treatment groups ranged from 45.5 to 54.6 years and most patients were white (average proportions across 3 treatment groups: 78.6%-86.7%). Clinically meaningful and statistically significant improvements in primary and key secondary efficacy end points were observed. Zilucoplan at a dose of 0.3 mg/kg SC daily resulted in a mean reduction from baseline of 6.0 points in the QMG score (placebo-corrected change, -2.8; P = .05) and 3.4 points in the MG Activities of Daily Living score (placebo-corrected change, -2.3; P = .04). Clinically meaningful and statistically significant improvements were also observed in other secondary end points, the MG Composite and MG Quality-of-Life scores. Outcomes for the 0.1-mg/kg SC daily dose were also statistically significant but slower in onset and less pronounced than with the 0.3-mg/kg dose. Rescue therapy (intravenous immunoglobulin or plasma exchange) was required in 3 of 15, 1 of 15, and 0 of 14 participants in the placebo, 0.1-mg/kg zilucoplan, and 0.3-mg/kg zilucoplan arms, respectively. Zilucoplan was observed to have a favorable safety and tolerability profile. Conclusions and Relevance: Zilucoplan yielded rapid, meaningful, and sustained improvements over 12 weeks in a broad population of patients with moderate to severe AChR-Ab-positive gMG. Near-complete complement inhibition appeared superior to submaximal inhibition. The observed safety and tolerability profile of zilucoplan was favorable. Trial Registration: ClinicalTrials.gov Identifier: NCT03315130.


Asunto(s)
Complemento C5/antagonistas & inhibidores , Inactivadores del Complemento/administración & dosificación , Miastenia Gravis/tratamiento farmacológico , Método Doble Ciego , Femenino , Humanos , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Autoadministración
2.
J Alzheimers Dis ; 73(3): 867-872, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31884471

RESUMEN

Digital technologies have the potential to assist people with dementia to monitor day to day activities and mitigate the risks of living independently. This purposive pilot study surveyed participants for frailty, wellbeing, and perceived carer burden using the 3Rings™ digital plug. 30 paired participants used the digital device for four months. People with dementia reported a decline in wellbeing and increased frailty. Family carers reported a decline in wellbeing but 18 reported a reduction in burden. The use of digital monitoring by family carers demonstrated a reduction in their perceived burden and the device was acceptable to people with mild dementia living alone.


Asunto(s)
Actividades Cotidianas/psicología , Cuidadores/psicología , Demencia/psicología , Calidad de Vida/psicología , Dispositivos de Autoayuda , Adulto , Anciano , Anciano de 80 o más Años , Costo de Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto
3.
Res Involv Engagem ; 5: 11, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30834143

RESUMEN

PLAIN ENGLISH SUMMARY: Whilst Patient and Public Involvement and Engagement (PPIE) are widely regarded as critical to developing clinical research, there is a perception that older adults may not be able to contribute and there is less emphasis on gaining a wide range of opinions before developing research questions or projects; for example an organisational change. This PPIE initiative used three PPIE processes including existing panels and wider networking to access older adults in the community who had used the hospital services and been discharged. Older adults expressed a range of views about their experience of discharge planning and this provided an important perspective on patients' research priorities associated with their personal independence. Efforts were taken to ensure representative views across a cross section of the population. As a result of this initial PPIE, a permanent, co-ordinated 'elders' panel has been established to ensure a representation of older adult views for research, service development and evaluation. This panel has permanent, fully supported members who provide reflection and feedback on any projects and programmes relating to older people's services in the City. ABSTRACT: Background Clinical academic research and service improvement is planned using Patient and Public Involvement and Engagement (PPIE) but older PPIE participants are consulted less often due to the perception that they are vulnerable or hard to engage. Objectives To consult frail older adults about a recently adopted service, discharge to assess (D2A), and to prioritise services improvements and research topics associated with the design and delivery of discharge from hospital. To use successive PPIE processes to enable a permanent PPIE panel to be established. Participants Following guidance from an established hospital PPI panel 27 older adult participants were recruited. Participants from Black, Asian and Minority Ethnic (BAME) communities, affluent and non-affluent areas and varied social circumstances were included. Methods Focus groups and individual interviews were conducted in participants own homes or nearby social venues. Results Priorities for discharge included remaining independent despite often feeling lonely at home; to remain in hospital if needed; and for services to ensure effective communication with families. The main research priority identified was facilitating independence, whilst establishing a permanent PPIE panel involving older adults was viewed favourably. Conclusions Taking a structured approach to PPIE enabled varied older peoples' voices to express their priorities and concerns into early discharge from hospital, as well as enabling the development of health services research into hospital discharge planning and management. Older people as participants identified research priorities after reflecting on their experiences. Listening and reflection enabled researchers to develop a new "Community PPIE Elders Panel" to create an enduring PPIE infrastructure for frail older housebound people to engage in research design, development and dissemination.

4.
JMIR Cancer ; 4(1): e8, 2018 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-29712628

RESUMEN

BACKGROUND: Distress after prostate cancer treatment is a substantial burden for up to one-third of men diagnosed. Physical and emotional symptoms and health service use can intensify, yet men are reticent to accept support. To provide accessible support that can be cost effectively integrated into care pathways, we developed a unique, Web-based, self-guided, cognitive-behavior program incorporating filmed and interactive peer support. OBJECTIVE: To assess feasibility of the intervention among men experiencing distress after prostate cancer treatment. Demand, acceptability, change in distress and self-efficacy, and challenges for implementation in clinical practice were measured. METHODS: A pre-post, within-participant comparison, mixed-methods research design was followed. Phase I and II were conducted in primary care psychological service and secondary care cancer service, respectively. Men received clinician-generated postal invitations: phase I, 432 men diagnosed <5 years; phase II, 606 men diagnosed <3.5 years. Consent was Web-based. Men with mild and moderate distress were enrolled. Web-based assessment included demographic, disease, treatment characteristics; distress (General Health Questionnaire-28); depression (Patient Health Questionnaire-9); anxiety (General Anxiety Disorder Scale-7); self-efficacy (Self-Efficacy for Symptom Control Inventory); satisfaction (author-generated, Likert-type questionnaire). Uptake and adherence were assessed with reference to the persuasive systems design model. Telephone interviews explored participant experience (phase II, n=10); interviews with health care professionals (n=3) explored implementation issues. RESULTS: A total of 135 men consented (phase I, 61/432, 14.1%; phase II, 74/606, 12.2%); from 96 eligible men screened for distress, 32% (30/96) entered the intervention (phase I, n=10; phase II, n=20). Twenty-four completed the Web-based program and assessments (phase I, n=8; phase II, n=16). Adherence for phase I and II was module completion rate 63% (mean 2.5, SD 1.9) versus 92% (mean 3.7, SD 1.0); rate of completing cognitive behavior therapy exercises 77% (mean 16.1, SD 6.2) versus 88% (mean 18.6, SD 3.9). Chat room activity occurred among 63% (5/8) and 75% (12/16) of men, respectively. In phase I, 75% (6/8) of men viewed all the films; in phase II, the total number of unique views weekly was 16, 11, 11, and 10, respectively. The phase II mood diary was completed by 100% (16/16) of men. Satisfaction was high for the program and films. Limited efficacy testing indicated improvement in distress baseline to post intervention: phase I, P=.03, r=-.55; phase II, P=.001, r=-.59. Self-efficacy improved for coping P=.02, r=-.41. Service assessment confirmed ease of assimilation into clinical practice and clarified health care practitioner roles. CONCLUSIONS: The Web-based program is acceptable and innovative in clinical practice. It was endorsed by patients and has potential to positively impact the experience of men with distress after prostate cancer treatment. It can potentially be delivered in a stepped model of psychological support in primary or secondary care. Feasibility evidence is compelling, supporting further evaluative research to determine clinical and cost effectiveness.

5.
Am J Physiol Endocrinol Metab ; 299(5): E741-51, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20682841

RESUMEN

Discrete fetal androgen excess during early gestation in rhesus monkeys (Macaca mulatta) promotes endocrine antecedents of adult polycystic ovary syndrome (PCOS)-like traits in female offspring. Because developmental changes promoting such PCOS-like metabolic dysfunction remain unclear, the present study examined time-mated, gravid rhesus monkeys with female fetuses, of which nine gravid females received 15 mg of testosterone propionate (TP) subcutaneously daily from 40 to 80 days (first to second trimesters) of gestation [term, mean (range): 165 (155-175) days], whereas an additional six such females received oil vehicle injections over the same time interval. During gestation, ultrasonography quantified fetal growth measures and was used as an adjunct for fetal blood collections. At term, all fetuses were delivered by cesarean section for postnatal studies. Blood samples were collected from dams and infants for glucose, insulin, and total free fatty acid (FFA) determinations. TP injections transiently accelerated maternal weight gain in dams, very modestly increased head diameter of prenatally androgenized (PA) fetuses, and modestly increased weight gain in infancy compared with concurrent controls. Mild to moderate glucose intolerance, with increased area-under-the-curve circulating insulin values, occurred in TP-injected dams during an intravenous glucose tolerance test in the early second trimester. Moreover, reduced circulating FFA levels occurred in PA fetuses during a third trimester intravenous glucagon-tolbutamide challenge (140 days gestation), whereas excessive insulin sensitivity and increased insulin secretion relative to insulin sensitivity occurred in PA infants during an intravenous glucose-tolbutamide test at ∼1.5 mo postnatal age. Data from these studies suggest that experimentally induced fetal androgen excess may result in transient hyperglycemic episodes in the intrauterine environment that are sufficient to induce relative increases in pancreatic function in PA infants, suggesting in this nonhuman primate model that differential programming of insulin action and secretion may precede adult metabolic dysfunction.


Asunto(s)
Intolerancia a la Glucosa/fisiopatología , Síndrome del Ovario Poliquístico/etiología , Propionato de Testosterona/farmacología , Animales , Animales Recién Nacidos , Área Bajo la Curva , Peso al Nacer/fisiología , Glucemia/metabolismo , Largo Cráneo-Cadera , Ácidos Grasos no Esterificados/sangre , Femenino , Prueba de Tolerancia a la Glucosa , Insulina/sangre , Resistencia a la Insulina/fisiología , Macaca mulatta , Embarazo
6.
Midwifery ; 26(3): e1-e13, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18692285

RESUMEN

OBJECTIVE: to develop a pragmatic service for pregnant smokers. DESIGN: identification and referral of pregnant smokers to specialist services using self-report gathered on routine pregnancy booking questionnaire augmented by a carbon monoxide breath test. Engagement by specialist smoking cessation midwives using telephone contact with the offer of clinic-based counselling for women who want help. Telephone support and pharmacy provision of nicotine replacement therapy for women who decide to quit. SETTING: three maternity units serving Glasgow in the West of Scotland. PARTICIPANTS: a relatively deprived population of 12,000 pregnant women each year in Glasgow. INTERVENTIONS: at maternity booking, women with either a carbon monoxide breath test result >7 parts per million or self-reporting to be a current smoker during the routine pregnancy booking questionnaire were identified as smokers. All smokers were referred on to the specially trained midwives who provided an opt-out smoking cessation intervention. This involved motivational interviewing to engage pregnant smokers during telephone contact. Women considering quitting were invited for a follow-up face-to-face meeting in a clinic setting. Women who set a quit date were offered withdrawal oriented therapy augmented by pharmacy-based nicotine replacement therapy. FINDINGS: booking midwives found it difficult to approach all pregnant women to talk about smoking. This was not made easier by the service requirement that all pregnant women should provide a carbon monoxide breath test at maternity booking. In one hospital, auxiliary nurses performed the carbon monoxide breath test and 2879 of 3219 (89%) women booking for antenatal care provided a sample, allowing most smokers to be identified. In another hospital where the carbon monoxide test was administered by midwives, only 1968 of 5570 (35%) women provided a carbon monoxide breath test sample; 61% of pregnant smokers were not identified and referred to specialist services. Of the 1936 pregnant smokers referred from all three hospitals, 386 (20%) attended a face-to-face appointment with specialist smoking cessation midwives, 370 (19%) set a quit date and 117 (6%) had quit 4 weeks after their quit date. IMPLICATIONS FOR PRACTICE: this service development provides a pragmatic approach to identify nearly all pregnant smokers at maternity booking, and an opt-out model to refer them to specialist smoking cessation services. Further research is required to establish if extra auxiliary staff in maternity booking clinics can optimise the identification and referral of pregnant smokers to specialist smoking cessation services. This telephone- and clinic-based specialist service engaged 20% of referred pregnant smokers to attend a face-to-face appointment with a specialist smoking cessation midwife. Further research is required to assess if home-based support would engage a greater proportion of pregnant smokers, or if an incentive scheme would achieve the same aim. In total, 117 of 370 (32%) women who set a quit date had quit smoking 4 weeks later, which compares fairly well with a figure of 40% for pregnant smokers in the English smoking treatment services.


Asunto(s)
Enfermeras Obstetrices/organización & administración , Complicaciones del Embarazo/prevención & control , Atención Prenatal/organización & administración , Cese del Hábito de Fumar/métodos , Prevención del Hábito de Fumar , Pruebas Respiratorias , Monóxido de Carbono/análisis , Consejo/organización & administración , Femenino , Estimulantes Ganglionares/uso terapéutico , Humanos , Nicotina/uso terapéutico , Investigación en Evaluación de Enfermería , Educación del Paciente como Asunto/organización & administración , Embarazo , Complicaciones del Embarazo/diagnóstico , Complicaciones del Embarazo/epidemiología , Desarrollo de Programa , Evaluación de Programas y Proyectos de Salud , Derivación y Consulta , Escocia/epidemiología , Fumar/epidemiología , Apoyo Social , Teléfono
7.
Biol Reprod ; 79(1): 154-63, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18385445

RESUMEN

Experimentally induced fetal androgen excess induces polycystic ovary syndrome-like traits in adult female rhesus monkeys (Macaca mulatta). Developmental changes leading to this endocrinopathy are not known. We therefore studied 15 time-mated, gravid female rhesus monkeys with known female fetuses. Nine dams received daily s.c. injections of 15 mg of testosterone propionate (TP), and six received injections of oil vehicle (control) from 40 through 80 days of gestation (term, 165 days; range, +/-10 days). All fetuses were delivered by cesarean section using established methods at term. Ultrasound-guided fetal blood sample collection and peripheral venous sample collection of dams and subsequent infants enabled determination of circulating levels of steroid hormones, LH and FSH. The TP injections elevated serum testosterone and androstenedione levels in the dams and prenatally androgenized (PA) fetuses. After cessation of TP injections, testosterone levels returned to values within the reference range for animals in these age groups, whereas serum androstenedione levels in PA infants were elevated. The TP injections did not increase estrogen levels in the dams or the PA fetuses or infants, yet conjugated estrogen levels were elevated in the TP-injected dams. Serum levels of LH and FSH were elevated in late-gestation PA fetuses, and LH levels were elevated in PA infants. These studies suggest that experimentally induced fetal androgen excess increases gonadotropin secretion in PA female fetuses and infants and elevates endogenous androgen levels in PA infants. Thus, in this nonhuman primate model, differential programming of the fetal hypothalamo-pituitary unit with concomitant hyperandrogenism provides evidence to suggest developmental origins of LH and androgen excess in adulthood.


Asunto(s)
Andrógenos/farmacología , Sistema Endocrino/fisiopatología , Feto/efectos de los fármacos , Síndrome del Ovario Poliquístico/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Virilismo/inducido químicamente , Andrógenos/sangre , Animales , Animales Recién Nacidos , Peso al Nacer/efectos de los fármacos , Estrógenos/sangre , Femenino , Feto/patología , Hormona Luteinizante/sangre , Macaca mulatta , Síndrome del Ovario Poliquístico/embriología , Síndrome del Ovario Poliquístico/patología , Síndrome del Ovario Poliquístico/fisiopatología , Embarazo , Efectos Tardíos de la Exposición Prenatal/sangre , Efectos Tardíos de la Exposición Prenatal/patología , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Efectos Tardíos de la Exposición Prenatal/veterinaria , Progesterona/sangre , Virilismo/sangre , Virilismo/patología , Virilismo/fisiopatología
8.
J S C Med Assoc ; 104(8): 252-4, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19326613

RESUMEN

An IWB is a test result that creates uncertainty. Explaining this result to patients can cause provider discomfort but the more the provider practices, the comfort level increases. HIV diagnosis is no longer considered a death sentence. It has become a manageable disease when patients enter care early. That is why it is important to encourage screening for all. The earlier a patient is linked to care the better the health outcome and this prevents ongoing HIV transmission.


Asunto(s)
Western Blotting , Infecciones por VIH/diagnóstico , Adolescente , Adulto , Factores de Edad , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores Sexuales , South Carolina/epidemiología
9.
Endocrinology ; 147(1): 615-23, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16179411

RESUMEN

GnRH II (pGlu-His-Trp-Ser-Try-Gly-Leu-Arg-Pro-GlyNH2), an evolutionarily conserved member of the GnRH family, stimulates reproductive behavior in a number of vertebrates. To explore a role for GnRH II in regulating primate sexual behavior, eight adult female common marmosets, each fitted with an indwelling intracerebroventricular (icv) cannula, were ovariectomized, implanted subcutaneously with empty (n = 4) or estradiol-filled (n = 4) SILASTIC brand capsules, and pair housed with an adult male mate. After icv infusion of vehicle or peptides, females were placed in an observation cage for 90 min, out of visual contact with other marmosets, before the 30-min behavioral test with their male partner. Compared with vehicle, GnRH II (1 and 10 microg) increased the total number of proceptive (sexual solicitation) behaviors (tongue flicking, proceptive stares, and frozen postures) exhibited by females toward their pair mates and specifically increased the frequency of freeze postures. Effects were maximal at 1 microg and not dependent upon estradiol supplementation. GnRH II agonists/GnRH I antagonists 135-18 (1 microg) and 132-25 (1 microg), which stimulate inositol phosphate production via the marmoset type II receptor, increased the frequency of total proceptive behavior but did not specifically stimulate freeze-posture behavior. In contrast, GnRH I, at 1 mug, did not alter the frequency of proceptive behaviors. Female receptivity (female compliance with male sexual behavior) was not altered by any of the peptides tested. These findings implicate a role for GnRH II and the cognate GnRH type II receptor in stimulating female marmoset sexual behavior.


Asunto(s)
Hormona Liberadora de Gonadotropina/farmacología , Conducta Sexual Animal/fisiología , Secuencia de Aminoácidos , Anfibios , Animales , Aves , Callithrix , Secuencia Conservada , Estradiol/farmacología , Femenino , Carpa Dorada , Hormona Liberadora de Gonadotropina/administración & dosificación , Hormona Liberadora de Gonadotropina/genética , Humanos , Inyecciones Intraventriculares , Reptiles , Conducta Sexual Animal/efectos de los fármacos , Especificidad de la Especie
10.
ILAR J ; 45(2): 116-31, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15111731

RESUMEN

Anovulatory infertility affects a large proportion of reproductive-aged women. Major improvements in successful clinical treatment of this prevalent disorder in women's health have been made possible because of biomedical research employing nonhuman primates. Experiments on female rhesus monkeys were the first to demonstrate that the key hypothalamic neurotransmitter, gonadotropin-releasing hormone, involved in stimulating pituitary gonadotropin synthesis, storage, and release was bioactive only when released in approximately hourly bursts. This breakthrough in understanding gonadotropin regulation enabled identification of hypogonadotropic, apparently normogonadotropic, and hypergonadotropic forms of anovulatory infertility, and development of appropriate stimulatory or inhibitory gonadotropin therapies. Treatments to overcome anovulatory infertility represent one of the major advances in clinical reproductive endocrinology during the last 25 yr. The future promise of nonhuman primate models for human ovulatory dysfunction, however, may be based on an increased understanding of molecular and physiological mechanisms responsible for fetal programming of adult metabolic and reproductive defects and for obesity-related, hyperinsulinemic impairment of oocyte development.


Asunto(s)
Anovulación/fisiopatología , Modelos Animales de Enfermedad , Infertilidad Femenina/fisiopatología , Enfermedades del Ovario/fisiopatología , Primates/fisiología , Animales , Femenino , Hormona Liberadora de Gonadotropina/metabolismo , Humanos , Hiperprolactinemia/fisiopatología , Hipotálamo/fisiopatología , Leptina/metabolismo , Primates/metabolismo , Estrés Fisiológico/fisiopatología , Factores de Tiempo
11.
Comp Med ; 53(4): 339-50, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-14524409

RESUMEN

While common marmosets are increasingly used as alternative primate models in biomedical research, their life history, specialized behavior and unique physiology are not well known. This paper describes important marmoset attributes that are particularly relevant for biomedical research, including reproduction, neurobiology, immunology, endocrine signaling, obesity and aging, in addition to fetal and postnatal development. While common marmosets exhibit characteristic anthropoid primate traits, they clearly differ from Old World primates and humans in a variety of functions, including reproduction, endocrine signaling and immunology. These differences, however, permit the use of common marmosets in unconventional research strategies targeted on human pathology.


Asunto(s)
Callithrix/fisiología , Investigación , Envejecimiento , Animales , Cruzamiento , Ecología , Femenino , Masculino , Modelos Animales , Filogenia , Reproducción
12.
Am J Hum Biol ; 15(3): 296-319, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12704707

RESUMEN

During the ovarian or menstrual cycle, prior to ovulation, many female primates exhibit a relatively prolonged follicular phase and terminate the postovulatory luteal phase with menstrual bleeding. The prolonged follicular phase is a trait that distinguishes primate from nonprimate species. It enables extended estrogen-induced proliferation and growth of the uterine endometrium prior to progesterone-induced maturation during the luteal phase to accommodate a potential pregnancy with a rapidly invading placenta. Progressive development of both an extended duration of estrogen-induced, preimplantation endometrial proliferation and a rapidly invading placenta across the Primate order may well have been necessary to accommodate differentiation and growth of an increasingly large fetal brain. Prolongation of the follicular phase in primates has also led to the isolation of the final stages of follicle selection (growth deviation of the dominant follicle from its contemporaries) solely within the follicular phase and thus outside the protection of luteal phase progesterone inhibition of pituitary luteinizing hormone (LH) secretion. Such primate reproductive characteristics put the latter stages of ovarian follicle selection at risk of exposure to excessive pituitary secretion of LH. Excessive secretion of LH during follicle selection could result not only in impaired follicle development, excessive ovarian androgen secretion, and ovulation failure, but also in excessive estrogenic stimulation of the uterine endometrium without intervening menstrual periods. Such reproductive abnormalities are all found in a single, prevalent infertility syndrome afflicting women in their reproductive years: polycystic ovary syndrome (PCOS). We propose that successful female reproductive adaptations to accommodate the growth demands of large-brained primate fetuses have facilitated a particular vulnerability of higher primates to hypergonadotropic disruption of ovulatory function, as found in PCOS.


Asunto(s)
Encéfalo/embriología , Ciclo Menstrual/fisiología , Síndrome del Ovario Poliquístico/fisiopatología , Adaptación Biológica , Animales , Anovulación , Encéfalo/anatomía & histología , Implantación del Embrión , Endometrio/crecimiento & desarrollo , Endometrio/fisiología , Femenino , Fase Folicular/fisiología , Hormonas/fisiología , Humanos , Filogenia , Placenta/fisiología , Embarazo , Primates , Trofoblastos/fisiología
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