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Featured researches published by Kathryn A. Martin.


The Journal of Clinical Endocrinology and Metabolism | 2010

Postmenopausal hormone therapy: An endocrine society scientific statement

Richard J. Santen; D. Craig Allred; Stacy P. Ardoin; David F. Archer; Norman F. Boyd; Glenn D. Braunstein; Henry G. Burger; Graham A. Colditz; Susan R. Davis; Marco Gambacciani; Barbara A. Gower; Victor W. Henderson; Wael N. Jarjour; Richard H. Karas; Michael Kleerekoper; Roger A. Lobo; JoAnn E. Manson; Jo Marsden; Kathryn A. Martin; Lisa Martin; Jo Ann V. Pinkerton; David R. Rubinow; Helena Teede; Diane Thiboutot; Wulf H. Utian

OBJECTIVE Our objective was to provide a scholarly review of the published literature on menopausal hormonal therapy (MHT), make scientifically valid assessments of the available data, and grade the level of evidence available for each clinically important endpoint. PARTICIPANTS IN DEVELOPMENT OF SCIENTIFIC STATEMENT: The 12-member Scientific Statement Task Force of The Endocrine Society selected the leader of the statement development group (R.J.S.) and suggested experts with expertise in specific areas. In conjunction with the Task Force, lead authors (n = 25) and peer reviewers (n = 14) for each specific topic were selected. All discussions regarding content and grading of evidence occurred via teleconference or electronic and written correspondence. No funding was provided to any expert or peer reviewer, and all participants volunteered their time to prepare this Scientific Statement. EVIDENCE Each expert conducted extensive literature searches of case control, cohort, and randomized controlled trials as well as meta-analyses, Cochrane reviews, and Position Statements from other professional societies in order to compile and evaluate available evidence. No unpublished data were used to draw conclusions from the evidence. CONSENSUS PROCESS A consensus was reached after several iterations. Each topic was considered separately, and a consensus was achieved as to content to be included and conclusions reached between the primary author and the peer reviewer specific to that topic. In a separate iteration, the quality of evidence was judged using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) system in common use by The Endocrine Society for preparing clinical guidelines. The final iteration involved responses to four levels of additional review: 1) general comments offered by each of the 25 authors; 2) comments of the individual Task Force members; 3) critiques by the reviewers of the Journal of Clinical Endocrinology & Metabolism; and 4) suggestions offered by the Council and members of The Endocrine Society. The lead author compiled each individual topic into a coherent document and finalized the content for the final Statement. The writing process was analogous to preparation of a multiauthored textbook with input from individual authors and the textbook editors. CONCLUSIONS The major conclusions related to the overall benefits and risks of MHT expressed as the number of women per 1000 taking MHT for 5 yr who would experience benefit or harm. Primary areas of benefit included relief of hot flashes and symptoms of urogenital atrophy and prevention of fractures and diabetes. Risks included venothrombotic episodes, stroke, and cholecystitis. In the subgroup of women starting MHT between ages 50 and 59 or less than 10 yr after onset of menopause, congruent trends suggested additional benefit including reduction of overall mortality and coronary artery disease. In this subgroup, estrogen plus some progestogens increased the risk of breast cancer, whereas estrogen alone did not. Beneficial effects on colorectal and endometrial cancer and harmful effects on ovarian cancer occurred but affected only a small number of women. Data from the various Womens Health Initiative studies, which involved women of average age 63, cannot be appropriately applied to calculate risks and benefits of MHT in women starting shortly after menopause. At the present time, assessments of benefit and risk in these younger women are based on lower levels of evidence.


Menopause | 2006

Estrogen therapy selectively enhances prefrontal cognitive processes: A randomized, double-blind, placebo-controlled study with functional magnetic resonance imaging in perimenopausal and recently postmenopausal women

Hadine Joffe; Janet E. Hall; Staci A. Gruber; Ingrid A. Sarmiento; Lee S. Cohen; Deborah A. Yurgelun-Todd; Kathryn A. Martin

Objective: Estrogen therapy (ET) seems to differentially effect cognitive processes in younger versus older postmenopausal women, suggesting a window of opportunity when ET is most beneficial. Cognitive improvement in younger postmenopausal women has been attributed to ETs influence on hot flushes and sleep, but empiric examination of the mediating role of menopause symptoms versus direct effects of ET on the brain is limited. Design: In a double-blind trial, 52 women were randomly assigned to estradiol 0.05 mg/day (n = 26) or placebo transdermal patches (n = 26) for 12 weeks. Women completed tests of memory, learning, and executive functioning, and hot flush and sleep assessments at baseline and study end. A subset of women (five ET treated, six placebo treated) also underwent blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) studies. Results: Nondepressed perimenopausal and postmenopausal women were studied. The majority had hot flushes and sleep impairment. Compared with placebo, ET selectively reduced errors of perseveration during verbal recall (P = 0.03), a frontal system-mediated function, but did not influence other cognitive processes. Women with baseline hot flushes had greater cognitive benefit with ET (P < 0.05). Cognitive benefit was not associated with sleep problems or its improvement. Measures of fMRI BOLD activation during tests of verbal and spatial working memory showed significant increases in frontal system activity with ET (P < 0.001). Conclusions: Estrogen therapy selectively improves executive functioning as demonstrated by reduced perseverative errors and prefrontal cortex activation during verbal recall tasks. Cognitive improvement with ET is associated with hot flushes, but not with sleep, suggesting that ET has a direct central nervous system effect, rather than an indirect effect mediated through improvement of sleep.


The New England Journal of Medicine | 2011

A Genetic Basis for Functional Hypothalamic Amenorrhea

Lisa M. Caronia; Cecilia Martin; Corrine K. Welt; Gerasimos P. Sykiotis; Richard Quinton; Apisadaporn Thambundit; Magdalena Avbelj; Sadhana Dhruvakumar; Lacey Plummer; Virginia A. Hughes; Stephanie B. Seminara; Paul A. Boepple; Yisrael Sidis; William F. Crowley; Kathryn A. Martin; Janet E. Hall; Nelly Pitteloud

BACKGROUND Functional hypothalamic amenorrhea is a reversible form of gonadotropin-releasing hormone (GnRH) deficiency commonly triggered by stressors such as excessive exercise, nutritional deficits, or psychological distress. Women vary in their susceptibility to inhibition of the reproductive axis by such stressors, but it is unknown whether this variability reflects a genetic predisposition to hypothalamic amenorrhea. We hypothesized that mutations in genes involved in idiopathic hypogonadotropic hypogonadism, a congenital form of GnRH deficiency, are associated with hypothalamic amenorrhea. METHODS We analyzed the coding sequence of genes associated with idiopathic hypogonadotropic hypogonadism in 55 women with hypothalamic amenorrhea and performed in vitro studies of the identified mutations. RESULTS Six heterozygous mutations were identified in 7 of the 55 patients with hypothalamic amenorrhea: two variants in the fibroblast growth factor receptor 1 gene FGFR1 (G260E and R756H), two in the prokineticin receptor 2 gene PROKR2 (R85H and L173R), one in the GnRH receptor gene GNRHR (R262Q), and one in the Kallmann syndrome 1 sequence gene KAL1 (V371I). No mutations were found in a cohort of 422 controls with normal menstrual cycles. In vitro studies showed that FGFR1 G260E, FGFR1 R756H, and PROKR2 R85H are loss-of-function mutations, as has been previously shown for PROKR2 L173R and GNRHR R262Q. CONCLUSIONS Rare variants in genes associated with idiopathic hypogonadotropic hypogonadism are found in women with hypothalamic amenorrhea, suggesting that these mutations may contribute to the variable susceptibility of women to the functional changes in GnRH secretion that characterize hypothalamic amenorrhea. Our observations provide evidence for the role of rare variants in common multifactorial disease. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and others; ClinicalTrials.gov number, NCT00494169.).


Molecular Microbiology | 1996

The P1 ParA protein and its ATPase activity play a direct role in the segregation of plasmid copies to daughter cells.

M A Davis; Lyndsay Radnedge; Kathryn A. Martin; Frances J. Hayes; Brenda Youngren; Stuart Austin

The P1 ParA protein is an ATPase that recognizes the parA promoter region where it acts to autoregulate the P1 parA–parB operon. The ParB protein is essential for plasmid partition and recognizes the cis‐acting partition site parS. The regulatory role of ParA is also essential because a controlled level of ParB protein is critical for partition. However, we show that this regulatory activity is not the only role for ParA in partition. Efficient partition can be achieved without autoregulation as long as Par protein levels are kept within a range of low values. The properties of ParA mutants in these conditions showed that ParA is essential for some critical step in the partition process that is independent of par operon regulation. The putative nucleotide‐binding site for the ParA ATPase was identified and disrupted by mutation. The resulting mutant was substantially defective for autoregulation and completely inactive for partition in a system in which the need for autoregulation is abolished. Thus, the ParA nucleotide‐binding site appears to be necessary both for the repressor activity of ParA and for some essential step in the partition process itself. We propose that the nucleotide‐bound form of the enzyme adopts a configuration that favours binding to the operator, but that the ATPase activity of ParA is required for some energetic step in partition of the plasmid copies to daughter cells.


The Journal of Clinical Endocrinology and Metabolism | 2000

Decrease in gonadotropin-releasing hormone (GnRH) pulse frequency with aging in postmenopausal women

Janet E. Hall; Helene B. Lavoie; Erica E. Marsh; Kathryn A. Martin

UNLABELLED Increasing evidence suggests that aging is associated with dynamic changes in the hypothalamic and pituitary components of the reproductive axis that are independent of changes in gonadal hormone secretion. This study was designed to determine the effect of age on GnRH pulse frequency in women in the absence of gonadal feedback using gonadotropin free alpha-subunit (FAS) and LH as neuroendocrine markers of endogenous GnRH secretion. All studies were performed in healthy, euthyroid postmenopausal women (PMW) during daytime hours. The impact of sampling interval and duration on assessment of pulse frequency in PMW was first examined in 10 women with a mean age of 61.6 +/- 8 yr (mean +/- SD), in whom blood was sampled every 5 min for 12 h. Each 5-min series was then reduced to simulate a 10-min series and then a 15-min series for pulse analysis, and the effect of 8 h compared with 12 h of sampling was determined. To define the changes in the frequency and amplitude of pulsatile hormone secretion with aging, 11 younger (45-55 yr) and 11 older (70-80 yr) PMW were then studied over 8 h at a 5-min sampling interval. In the initial series, the mean interpulse intervals (IPIs) for FAS were 53.8 +/- 3.6, 69.2 +/- 3.9, and 87.6 +/- 7.3 min at sampling intervals of 5, 10, and 15 min, respectively (P < 0.0005). The LH IPI also increased progressively with sampling intervals of 5, 10, and 15 min (54.4 +/- 2.5, 70.4 +/- 2.3, and 91.1 +/- 4.4 min; P < 0.0001). At the 5-min sampling interval, the calculated number of pulses/24 h was not different between a 12-h series compared with an 8-h series for either FAS or LH. In the second series of studies, the older PMW had lower gonadotropin levels (LH, 86.5 +/- 8.8 vs. 51.3 +/- 7.7 IU/L, P < 0.01; FSH, 171.6 +/- 16.9 vs. 108.2 +/- 10.5 IU/L, P < 0.005; FAS, 1021.5 +/- 147.4 vs. 425.6 +/- 89.6 ng/L, P < 0.005, in younger and older PMW, respectively) despite no differences in estrone or estradiol levels. The older PMW also demonstrated a slower FAS pulse frequency compared with their younger counterparts, as reflected in an increased FAS IPI (52.6 +/- 3.1 and 70.6 +/- 5.9 min; P < 0.002). The difference in IPIs between younger and older PMW was not statistically significant for LH (65.4 +/- 5.6 and 71.8 +/- 6.6 min for younger and older PMW, respectively). FAS pulse amplitude was decreased in older PMW compared with younger PMW (431.7 +/- 66.2 vs. 224.6 +/- 81.9 ng/L; P < 0.01), whereas the decrease in LH pulse amplitude with age was of borderline statistical significance (23.2 +/- 3.1 vs. 15.9 +/- 2.1 IU/L; P = 0.09). IN CONCLUSION 1) the use of a 5-min sampling interval and measurement of FAS as the primary marker of GnRH pulse generator activity indicate that GnRH pulse frequency in younger PMW is faster than previously reported, but not increased over that seen in the late follicular phase and midcycle surge in women with intact ovarian function; and 2) the marked decrease in FAS pulse frequency with age provides evidence of age-related changes in the hypothalamic component of the reproductive axis that are independent of changes in gonadal function.


The Journal of Clinical Endocrinology and Metabolism | 2011

Expanding the Phenotype and Genotype of Female GnRH Deficiency

Natalie D. Shaw; Stephanie B. Seminara; Corrine K. Welt; Margaret G. Au; Lacey Plummer; Virginia A. Hughes; Andrew A. Dwyer; Kathryn A. Martin; Richard Quinton; Verónica Mericq; Paulina M. Merino; James F. Gusella; William F. Crowley; Nelly Pitteloud; Janet E. Hall

CONTEXT GnRH deficiency is a rare genetic disorder of absent or partial pubertal development. The clinical and genetic characteristics of GnRH-deficient women have not been well-described. OBJECTIVE To determine the phenotypic and genotypic spectrum of a large series of GnRH-deficient women. DESIGN, SETTING, AND SUBJECTS Retrospective study of 248 females with GnRH deficiency evaluated at an academic medical center between 1980 and 2010. MAIN OUTCOME MEASURES Clinical presentation, baseline endogenous GnRH secretory activity, and DNA sequence variants in 11 genes associated with GnRH deficiency. RESULTS Eighty-eight percent had undergone pubarche, 51% had spontaneous thelarche, and 10% had 1-2 menses. Women with spontaneous thelarche were more likely to demonstrate normal pubarche (P = 0.04). In 27% of women, neuroendocrine studies demonstrated evidence of some endogenous GnRH secretory activity. Thirty-six percent (a large excess relative to controls) harbored a rare sequence variant in a gene associated with GnRH deficiency (87% heterozygous and 13% biallelic), with variants in FGFR1 (15%), GNRHR (6.6%), and PROKR2 (6.6%) being most prevalent. One woman had a biallelic variant in the X-linked gene, KAL1, and nine women had heterozygous variants. CONCLUSIONS The clinical presentation of female GnRH deficiency varies from primary amenorrhea and absence of any secondary sexual characteristics to spontaneous breast development and occasional menses. In this cohort, rare sequence variants were present in all of the known genes associated with GnRH deficiency, including the novel identification of GnRH-deficient women with KAL1 variants. The pathogenic mechanism through which KAL1 variants disrupt female reproductive development requires further investigation.


The Journal of Clinical Endocrinology and Metabolism | 2008

Approach to the Patient with Menopausal Symptoms

Kathryn A. Martin; JoAnn E. Manson

Many women experience menopausal symptoms during the menopausal transition and postmenopausal years. Hot flashes, the most common symptom, typically resolve after several years, but for 15-20% of women, they interfere with quality of life. For these women, estrogen therapy, the most effective treatment for hot flashes, should be considered. The decision to use hormone therapy involves balancing the potential benefits of hormone therapy against its potential risks. Accumulating data suggest that initiation of estrogen many years after menopause is associated with excess coronary risk, whereas initiation soon after menopause is not. Therefore, most now agree that short-term estrogen therapy, using the lowest effective estrogen dose, is a reasonable option for recently menopausal women with moderate to severe symptoms who are in good cardiovascular health. Short-term therapy is considered to be not more than 4-5 yr because symptoms diminish after several years, whereas the risk of breast cancer increases with longer duration of hormone therapy. A minority of women may need long-term therapy for severe, persistent vasomotor symptoms after stopping hormone therapy. However, these women should first undergo trials of nonhormonal options such as gabapentin, selective serotonin reuptake inhibitors, or serotonin norepinephrine reuptake inhibitors, returning to estrogen only if these alternatives are ineffective or cause significant side effects. Low-dose vaginal estrogens are highly effective for genitourinary atrophy symptoms, with minimal systemic absorption and endometrial effects.


The Journal of Clinical Endocrinology and Metabolism | 2011

GnRH-Deficient Phenotypes in Humans and Mice with Heterozygous Variants in KISS1/Kiss1

Yee-Ming Chan; Sarabeth Broder-Fingert; Sophia Paraschos; Risto Lapatto; Margaret G. Au; Virginia A. Hughes; Suzy D. C. Bianco; Le Min; Lacey Plummer; Felecia Cerrato; Adelaide De Guillebon; I-Hsuan Wu; Fazal Wahab; Andrew A. Dwyer; Susan Kirsch; Richard Quinton; Tim Cheetham; Metin Ozata; Svetlana Ten; Jean-Pierre Chanoine; Nelly Pitteloud; Kathryn A. Martin; R. Schiffmann; Hetty J. van der Kamp; Shahla Nader; Janet E. Hall; Ursula B. Kaiser; Stephanie B. Seminara

CONTEXT KISS1 is a candidate gene for GnRH deficiency. OBJECTIVE Our objective was to identify deleterious mutations in KISS1. PATIENTS AND METHODS DNA sequencing and assessment of the effects of rare sequence variants (RSV) were conducted in 1025 probands with GnRH-deficient conditions. RESULTS Fifteen probands harbored 10 heterozygous RSV in KISS1 seen in less than 1% of control subjects. Of the variants that reside within the mature kisspeptin peptide, p.F117L (but not p.S77I, p.Q82K, p.H90D, or p.P110T) reduces inositol phosphate generation. Of the variants that lie within the coding region but outside the mature peptide, p.G35S and p.C53R (but not p.A129V) are predicted in silico to be deleterious. Of the variants that lie outside the coding region, one (g.1-3659C→T) impairs transcription in vitro, and another (c.1-7C→T) lies within the consensus Kozak sequence. Of five probands tested, four had abnormal baseline LH pulse patterns. In mice, testosterone decreases with heterozygous loss of Kiss1 and Kiss1r alleles (wild-type, 274 ± 99, to double heterozygotes, 69 ± 16 ng/dl; r(2) = 0.13; P = 0.03). Kiss1/Kiss1r double-heterozygote males have shorter anogenital distances (13.0 ± 0.2 vs. 15.6 ± 0.2 mm at P34, P < 0.001), females have longer estrous cycles (7.4 ± 0.2 vs. 5.6 ± 0.2 d, P < 0.01), and mating pairs have decreased litter frequency (0.59 ± 0.09 vs. 0.71 ± 0.06 litters/month, P < 0.04) and size (3.5 ± 0.2 vs. 5.4 ± 0.3 pups/litter, P < 0.001) compared with wild-type mice. CONCLUSIONS Deleterious, heterozygous RSV in KISS1 exist at a low frequency in GnRH-deficient patients as well as in the general population in presumably normal individuals. As in Kiss1(+/-)/Kiss1r(+/-) mice, heterozygous KISS1 variants in humans may work with other genetic and/or environmental factors to cause abnormal reproductive function.


Fertility and Sterility | 2009

Stimulation of spermatogenesis with recombinant human follicle-stimulating hormone (follitropin alfa; GONAL-f®): long-term treatment in azoospermic men with hypogonadotropic hypogonadism

Alvin M. Matsumoto; Peter J. Snyder; Shalender Bhasin; Kathryn A. Martin; Thomas J. Weber; Stephen J. Winters; Daniel Spratt; Jim Brentzel; Louis St. L. O'dea

OBJECTIVE To demonstrate the efficacy and safety of follitropin alfa administered with hCG on spermatogenesis in adult male hypogonadotropic hypogonadism (HH) patients. DESIGN Phase III, multicenter, open-label, noncomparative. SETTING Seven US medical centers. PATIENT(S) A total of 36 adult males with severe HH. INTERVENTION(S) A total of 1,000 U hCG on alternate days for 3 to 6 months, with dose adjustments after 2 months, if necessary, to normalize T levels, followed by follitropin alfa 150 U and hCG on the same alternate days for 18 months, with dose adjustments as necessary. MAIN OUTCOME MEASURE(S) Proportion of patients with sperm density > or =1.5 x 10(6)/mL. Pubertal advancement and long-term safety and tolerability were also evaluated. RESULT(S) In total, 22 of 29 patients (75.9%) who received > or =1 dose of follitropin alfa and 20 of 25 patients (80%) who completed 18 months of hCG + follitropin alfa treatments achieved a sperm concentration > or =1.5 x 10(6)/mL. A sperm concentration >20 x 10(6)/mL was achieved by 8 of 29 men (27.5%). Median sperm concentration at 18 months was 5.2 x 10(6)/mL. Pubertal development continued during the study, and testis volumes increased. Five clinical pregnancies were achieved. Acne (52% of patients) was the most common side effect, and gynecomastia was reported in 10% of patients. CONCLUSION(S) Long-term treatment of azoospermic HH men using follitropin alfa and hCG is effective for stimulating spermatogenesis and is well-tolerated.


Neuroendocrinology | 1998

Is GnRH Reduced at the Midcycle Surge in the Human

Kathryn A. Martin; Corrine K. Welt; Ann E. Taylor; Julie A. Smith; William F. Crowley; Janet E. Hall

Recent studies indicate that the midcycle gonadotropin surge in the human occurs without an increase in hypothalamic gonadotropin-releasing hormone (GnRH) pulse frequency. In addition, previous studies employing a GnRH antagonist to provide a semiquantitative estimate of endogenous GnRH secretion suggest that the overall amount of GnRH secreted is decreased at the time of the surge. To investigate the hypothesis that a normal gonadotropin surge can be generated in the human with a decreased amount of GnRH at the midcycle, 7 GnRH-deficient subjects underwent two cycles of a physiologic regimen of intravenous pulsatile GnRH therapy. In the control cycle, 75 ng/kg/bolus of GnRH, a dose known to be sufficient for folliculogenesis, was administered throughout the cycle, using physiological frequencies. In a second cycle, the bolus dose of GnRH was decreased by one-half log order to 25 ng/kg just prior to the luteinizing hormone surge and returned to 75 ng/kg after documented ovulation. All cycles were ovulatory. The peak luteinizing hormone level (77.4±9.7 vs. 67.5±17.6 IU/l) did not differ between the control and decreased GnRH cycles. There was no difference in the peak serum estradiol level (475.8±144.1 vs. 493.2±93.0 pg/ml), follicular phase length (15.0±1.3 vs. 14.8±0.6 days), or progesterone level (22.4±5.1 vs. 34.8±5.7 ng/ml) on day 6 of the luteal phase in the control and decreased GnRH cycles, respectively. Three pregnancies were achieved in each of the control and reduced GnRH cycles. We conclude that a decreased overall amount of GnRH generates a normal midcycle gonadotropin surge and has no significant impact on luteal phase adequacy or fertility. These results provide further evidence that a decrease in endogenous hypothalamic GnRH secretion may occur at the midcycle in normal women. This study also provides evidence that the GnRH requirements for normal follicular and luteal phase dynamics may well be greater than those required for generation of a normal midcycle gonadotropin surge and ovulation in women.

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JoAnn E. Manson

Brigham and Women's Hospital

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