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1.
Proc Natl Acad Sci U S A ; 115(42): 10576-10581, 2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30279178

RESUMO

Dynamic nuclear polarization (DNP) has enabled enormous gains in magnetic resonance signals and led to vastly accelerated NMR/MRI imaging and spectroscopy. Unlike conventional cw-techniques, DNP methods that exploit the full electron spectrum are appealing since they allow direct participation of all electrons in the hyperpolarization process. Such methods typically entail sweeps of microwave radiation over the broad electron linewidth to excite DNP but are often inefficient because the sweeps, constrained by adiabaticity requirements, are slow. In this paper, we develop a technique to overcome the DNP bottlenecks set by the slow sweeps, using a swept microwave frequency comb that increases the effective number of polarization transfer events while respecting adiabaticity constraints. This allows a multiplicative gain in DNP enhancement, scaling with the number of comb frequencies and limited only by the hyperfine-mediated electron linewidth. We demonstrate the technique for the optical hyperpolarization of 13C nuclei in powdered microdiamonds at low fields, increasing the DNP enhancement from 30 to 100 measured with respect to the thermal signal at 7T. For low concentrations of broad linewidth electron radicals [e.g., TEMPO ((2,2,6,6-tetramethylpiperidin-1-yl)oxyl)], these multiplicative gains could exceed an order of magnitude.

2.
Climacteric ; 20(6): 531-532, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29057667

RESUMO

It took many years since the initial publication of data from the Women's Health Initiative (WHI) study until further analyses and additional accumulated clinical information allowed realization of the full scope of its results. At first, the focus was on morbidity, mainly the slightly higher incidence of cardiovascular events and breast cancer cases among postmenopausal hormone users. Then, the age factor became evident, and the good safety profile of hormone therapy in healthy women initiating treatment near menopause and using it for up to 10 years eased the previous concerns. Now, 15 years after the first release of the WHI data, long-term follow-up of the WHI cohort enables consideration of mortality records as well. These data were recently summarized by the WHI investigators as follows: 'Among postmenopausal women, hormone therapy with CEE plus MPA for a median of 5.6 years or with CEE alone for a median of 7.2 years was not associated with risk of all-cause, cardiovascular, or cancer mortality during a cumulative follow-up of 18 years.' It seems that the bitter debate on the hazards of postmenopausal hormone therapy has come to an end, since the existing database permits clear and rationalized prescribing decisions.


Assuntos
Terapia de Reposição de Estrogênios , Menopausa , Mortalidade/tendências , Feminino , Humanos , Saúde da Mulher
3.
Climacteric ; 20(6): 528-530, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28613955

RESUMO

Sleep is mandatory for life and therefore any sleep deprivation or disruption might carry ill-health outcomes. The optimal night's sleep duration seems to be around 7 h, as too little sleep and too much sleep have been found to be associated with a variety of changes in well-being, physical and psychological parameters. This mini-review enlightens the potential health consequences of sleep disturbance relevant to menopause and midlife women's health. These include cardiovascular and metabolic derangements, cognitive impairment, osteoporosis, and cancer-related perspectives. Still, the current knowledge suggests that, even if statistically significant associations are detected, the absolute excessive risks are relatively small or modest.


Assuntos
Menopausa , Transtornos do Sono-Vigília , Sono , Feminino , Humanos
4.
Climacteric ; 20(5): 402-413, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28805475

RESUMO

The US Preventive Services Task Force (USPSTF) Draft Recommendation statement on Menopausal Hormone Therapy: Primary Prevention for Chronic Diseases, released in May 2017, perpetuates a major disconnect between the primary population affected, women within roughly 10 years of menopause, and the data cited. Furthermore, major elements of the evidence relied upon have been misinterpreted or misstated, particularly in regard to coronary heart disease and breast cancer, for which there is no statistically significant evidence of harm. As currently drafted, the recommendations reiterate the USPSTF statements of 2012, 2005 and 2002, and will perpetuate egregious harm to the public health. In an attempt to avoid that outcome and to facilitate a return to rational discourse regarding menopausal hormone therapy, an ad hoc group of experts in menopausal health submitted this comprehensive response to the USPSTF.


Assuntos
Terapia de Reposição de Estrogênios , Menopausa , Prevenção Primária , Neoplasias da Mama/epidemiologia , Doenças Cardiovasculares/epidemiologia , Doença Crônica/prevenção & controle , Doença das Coronárias/epidemiologia , Terapia de Reposição de Estrogênios/efeitos adversos , Terapia de Reposição de Estrogênios/métodos , Estrogênios Conjugados (USP) , Feminino , Humanos , Acetato de Medroxiprogesterona , Pessoa de Meia-Idade , Pós-Menopausa , Prevenção Primária/organização & administração , Fatores de Risco , Fatores de Tempo , Estados Unidos , Saúde da Mulher
5.
Climacteric ; 19(3): 249-51, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27075839

RESUMO

Many menopause specialists follow the principle of prescribing postmenopausal hormone therapy (HT) for the shortest duration needed, in order to decrease the risk of some related serious adverse effects, such as breast cancer. Based on several large studies, it seems, however, that withdrawal of HT may be associated with immediate, though small increased risk of coronary heart disease and stroke. Cessation of HT correlates with increased risk of fractures as well. This information should be relayed to hormone users while discussing the continuation of HT with their health-care provider, but, since the potential cardiovascular harm is actually very small, it should not deter symptomatic women from using HT when needed.


Assuntos
Doenças Cardiovasculares/epidemiologia , Terapia de Reposição de Estrogênios/métodos , Pós-Menopausa , Doenças Cardiovasculares/etiologia , Estrogênios/administração & dosagem , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Fatores de Tempo , Saúde da Mulher
6.
Climacteric ; 19(5): 423-5, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26914101

RESUMO

Recently, there has been a growing interest in better understanding of the adult-type attention deficit hyperactive disorder (ADHD). It is now accepted that many children with ADHD continue to have symptoms later in life, although the characteristics of the disease may change substantially in adults. Data are emerging on ADHD in midlife and old age and some studies analyze gender differences and co-morbidities during the lifespan of ADHD patients. This short communication discusses the possible resemblance of certain menopausal symptoms and those of adult ADHD and the potential contribution of the female hormonal environment. Further, there might be a promising role for psychostimulants, the mainstay of ADHD management, as treatment of impairment of some executive function domains in menopausal women.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Menopausa/psicologia , Feminino , Humanos , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica
7.
Climacteric ; 19(5): 430-2, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27327261

RESUMO

Decades ago, postmenopausal hormone replacement was considered the panacea for midlife women. Prevention of the age-related cognitive decline was among the top alleged benefits of this therapy. However, the data from the Women's Health Initiative Memory Study (WHI-WHIMS) study showed the opposite, indicating worsening of several cognitive domains in hormone users. Since WHIMS recruited women who were 65 years or older, it became crucial to investigate the effects of hormone therapy in the early menopause as well. Recent studies, such as WHIMS-Young, the Kronos Early Estrogen Prevention Study and the Early versus Late Intervention Trial with Estradiol targeted the younger women, and indeed showed that hormone therapy may have positive cognitive outcomes in this age group. Whether or not hormone therapy has an effect on already demented women remains to be further explored, as data are scarce.


Assuntos
Envelhecimento , Doença de Alzheimer/tratamento farmacológico , Cognição/efeitos dos fármacos , Terapia de Reposição de Estrogênios/métodos , Estrogênios Conjugados (USP)/uso terapêutico , Menopausa/efeitos dos fármacos , Feminino , Humanos , Memória/efeitos dos fármacos , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Saúde da Mulher
8.
Climacteric ; 19(3): 247-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27021900

RESUMO

Many studies have investigated potential links between postmenopausal hormone therapy (HT) and the risk for colorectal cancer. Most of these studies showed some reduction in risk, but association with the exact grade of the tumor or with cancer mortality is less consistent. Activation of estrogen receptor beta (ERß) related cellular pathways is probably the pathophysiological basis for this HT effect, since ERßs exert antiproliferative and pro-apoptotic signaling, inhibit inflammatory signaling and modulate the tumor microenvironment. To note, the impact on health may not be substantial as the absolute numbers point at the order of only a few saved cases per 10 000 women per year of hormone use.


Assuntos
Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/prevenção & controle , Terapia de Reposição de Estrogênios , Pós-Menopausa , Adulto , Idoso , Idoso de 80 Anos ou mais , Receptor beta de Estrogênio/efeitos dos fármacos , Receptor beta de Estrogênio/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco
9.
Climacteric ; 19(6): 551-552, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27585541

RESUMO

Circadian rhythm is an internal biological clock which initiates and monitors various physiological processes with a fixed time-related schedule. The master circadian pacemaker is located in the suprachiasmatic nucleus in the hypothalamus. The circadian clock undergoes significant changes throughout the life span, at both the physiological and molecular levels. This cyclical physiological process, which is very complex and multifactorial, may be associated with metabolic alterations, atherosclerosis, impaired cognition, mood disturbances and even development of cancer. Sex differences do exist, and the well-known sleep disturbances associated with menopause are a good example. Circadian rhythm was detected in the daily pattern of hot flushes, with a peak in the afternoons. Endogenous secretion of melatonin decreases with aging across genders, and, among women, menopause is associated with a significant reduction of melatonin levels, affecting sleep. Although it might seem that hot flushes and melatonin secretion are likely related, there are not enough data to support such a hypothesis.


Assuntos
Ritmo Circadiano/fisiologia , Menopausa/fisiologia , Envelhecimento/fisiologia , Feminino , Fogachos , Humanos , Melatonina/fisiologia , Pessoa de Meia-Idade , Caracteres Sexuais , Transtornos do Sono-Vigília/fisiopatologia , Núcleo Supraquiasmático/fisiologia
10.
Climacteric ; 18(6): 775-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26329986

RESUMO

White matter hyperintensities (WMH) are areas of high intensity observed in brain MRI scans. They are usually seen in normal aging but also in a number of neurological and psychiatric disorders. One of the underlying mechanisms is ischemia, expressed as small vessel disease. Since the volume of WMH may correlate with cognition, and an ongoing debate links postmenopausal hormone therapy with stroke and a decline in certain cognitive domains, several MRI studies have addressed this potential association. Two major randomized, placebo-controlled trials - WHIMS and KEEPS, the first including elderly women and the second recruiting recently menopausal women, did not demonstrate any safety concerns in this respect in hormone users.


Assuntos
Doenças Cardiovasculares/complicações , Terapia de Reposição de Estrogênios/efeitos adversos , Fogachos/fisiopatologia , Substância Branca/patologia , Fatores Etários , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade
11.
Climacteric ; 18(6): 773-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25812628

RESUMO

Recent epidemiological studies from various countries point at the mounting incidence of cancer. This continuous increase in the number of cancer cases will keep its pace in the future. The lifetime risk of cancer for people born since 1960 is forecast to be more than 50%. Thus cancer becomes the major health problem, and policy-makers should plan ahead how to implement effective prevention programs, on the one hand, and optimize the strategy for better diagnosis, treatment and surveillance of cancer patients on the other hand.


Assuntos
Previsões , Neoplasias/epidemiologia , Fatores Etários , Feminino , Humanos , Incidência , Longevidade , Masculino , Neoplasias/mortalidade , Medição de Risco
12.
Climacteric ; 18(6): 770-2, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25868822

RESUMO

Even lay persons know that a sedentary lifestyle is unhealthy. Still, the majority of people do not comply with current recommendations for physical activity. Data on the ill effects of sedentarism keep on increasing, clearly showing a significant adverse impact and increased risk for cardiovascular disease, cancer, fracture and various overweight-related metabolic conditions. The simple fact that prolonged sitting is associated with a shorter life span must be repeatedly discussed with our patients.


Assuntos
Longevidade , Atividade Motora/fisiologia , Comportamento Sedentário , Saúde da Mulher , Feminino , Humanos , Saúde da Mulher/estatística & dados numéricos
13.
Climacteric ; 18(5): 666-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25728515

RESUMO

The perception that certain body cavities and spaces that are heavily inhabited by micro-organisms should be regarded as 'external' to the body function is no longer valid. Extensive research during recent years has demonstrated the importance of those microbes to normal physiology, which means that the human body and those tiny organisms are actually symbiotic. The major point of interaction between the human body and the microbiome is the gut. There are also gender-specific aspects for this symbiosis: bacterial vaginosis has serious implications for female morbidity, including reports of pelvic inflammatory disease, adverse pregnancy outcomes, increased susceptibility to sexually transmitted infections and infertility. Re-establishing a normal flora might be beneficial and therefore the use of probiotics and re-colonization by 'healthy' bacteria have become very popular. Probiotics may serve as an adjunct for treating recurrences of urogenital infections and vaginal atrophy. Some animal studies have pointed at potential beneficial effects of Lactobacilli species on bone health.


Assuntos
Doenças Urogenitais Femininas/microbiologia , Microbiota/fisiologia , Complicações na Gravidez/microbiologia , Feminino , Humanos , Gravidez , Probióticos/uso terapêutico , Simbiose/fisiologia
14.
Climacteric ; 18(5): 663-5, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25668438

RESUMO

Every registered medication has an information insert in its package. This patient leaflet provides information on the product, which includes clinical pharmacology, recommended dose, mode of administration, how supplied, and a large section contains warnings and contraindications, adverse reactions, and precautions. Most of the prescribers do not read the patient information leaflets and do not discuss it with the users, whereas some patients do read it thoroughly. This may create worries and uncertainties resulting in reduced compliance to treatment. With easy access of patients to information on drugs that they use, mainly through the electronic media, it is very important that the text and contents of these patient leaflets are simple to understand and readable. Although information from official health agencies is superior to net-based sources, the patient information leaflets should be improved and become more user-friendly and less frightening.


Assuntos
Informação de Saúde ao Consumidor , Rotulagem de Medicamentos , Comunicação em Saúde/normas , Preparações Farmacêuticas , Comunicação em Saúde/métodos , Humanos
15.
Climacteric ; 18(4): 441-3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25962085

RESUMO

There is no debate any more on the good safety profile of postmenopausal hormone therapy (HT) in healthy perimenopausal and early postmenopausal women, but there are still many open issues related to the consequences of long-term HT, especially in older women. A recent Cochrane meta-analysis showed that women who started HT less than 10 years after the menopause had lower mortality and coronary heart disease (CHD), but more venous thromboembolism (DVT). However, in those who started treatment more than 10 years after the menopause, there was high-quality evidence that it had little effect on death or CHD between HT and placebo groups but there was an increased risk of stroke and DVT. In contrast, many large, observational studies such as a recent one from Finland (3.3 million years of HT exposure) have shown that the risk of CHD or stroke death and all-cause mortality was significantly reduced, both in those who initiated HT below or above age 60 years. Because of conflicting data concerning long-term HT use, it seems that every health-care provider chooses as reference those studies that can support his/her individual views and therapeutic approach.


Assuntos
Doenças Cardiovasculares/induzido quimicamente , Terapia de Reposição de Estrogênios/efeitos adversos , Fatores Etários , Idoso , Viés , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/prevenção & controle , Esquema de Medicação , Terapia de Reposição de Estrogênios/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Medição de Risco , Fatores de Tempo
16.
Climacteric ; 18(6): 802-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26397968

RESUMO

Menopausal women very often complain of vulvovaginal atrophy (VVA)-related symptoms, which mainly include dryness, irritation, dyspareunia and pain. The ideal therapeutic approach is to use systemic or intravaginal estrogen, which has proved to be effective. However, because of safety concerns that were raised after the publication of the Women's Health Initiative data, non-estrogenic and non-hormonal therapies for VVA have been developed and heavily promoted. Many menopause specialists believe that the flow of information on the newer products indicated for VVA seems to include an inaccurate message, which downgrades the use of estrogenic preparations and upgrades modern non-estrogenic therapies. Both media and medical sources have created an atmosphere of exaggerated worries over intravaginal estrogen therapies, which are not substantiated by hard clinical facts.


Assuntos
Comunicação , Terapia de Reposição de Estrogênios/efeitos adversos , Estrogênios/administração & dosagem , Vagina/patologia , Vulva/patologia , Atrofia/complicações , Atrofia/tratamento farmacológico , Estrogênios/efeitos adversos , Medicina Baseada em Evidências , Feminino , Humanos , Menopausa , Preferência do Paciente , Guias de Prática Clínica como Assunto , Padrões de Prática Médica
17.
Climacteric ; 18(1): 6-10, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25318377

RESUMO

Clinical guidelines may change with time, as more information from topline studies emerges. Calcium plus vitamin D supplementation became routine decades ago, especially in the older population, based on the assumption that it may promote bone health and prevent fractures, and perhaps induce additional favorable health outcomes. During the past years, an ongoing debate defies this paradigm, mainly because of a potential cardiovascular risk on the one hand, and uncertainty in regard to the extent of the beneficial bone effects on the other hand. The following article summarizes the main recent developments, trying to put some order into the controversial information and opinions which have been published in the medical literature. We conclude that the best current evidence supports a primary strategy of obtaining recommended intakes of calcium and vitamin D from dietary sources. But, since most western diets are inadequate in that regard, and since there is no clear evidence of harm from modest supplementation (up to 1000 mg of elemental calcium and 400 IU of vitamin D3), supplementation is appropriate when dietary intake is inadequate.


Assuntos
Cálcio da Dieta/efeitos adversos , Doenças Cardiovasculares/etiologia , Cálcio da Dieta/administração & dosagem , Suplementos Nutricionais/efeitos adversos , Feminino , Fraturas Ósseas/prevenção & controle , Humanos , Masculino , Recomendações Nutricionais , Vitamina D/administração & dosagem , Vitamina D/efeitos adversos , Vitaminas/administração & dosagem , Vitaminas/efeitos adversos
18.
Phys Rev Lett ; 112(7): 077601, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24579636

RESUMO

We report an observation of long-lived spin-singlet states in a 13C-1H spin pair in a zero magnetic field. In 13C-labeled formic acid, we observe spin-singlet lifetimes as long as 37 s, about a factor of 3 longer than the T1 lifetime of dipole polarization in the triplet state. In contrast to common high-field experiments, the observed coherence is a singlet-triplet coherence with a lifetime T2 longer than the T1 lifetime of dipole polarization in the triplet manifold. Moreover, we demonstrate that heteronuclear singlet states formed between a 1H and a 13C nucleus can exhibit longer lifetimes than the respective triplet states even in the presence of additional spins that couple to the spin pair of interest. Although long-lived homonuclear spin-singlet states have been extensively studied, this is the first experimental observation of analogous singlet states in heteronuclear spin pairs.

19.
Climacteric ; 17(6): 657-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25203615

RESUMO

The easy access to measurement of serum 25-hydroxyvitamin D (vitD) levels created a surge in interest to learn more of its potential health benefits and its association with prevention of chronic diseases. VitD effects on bone and fracture risk were studied extensively, resulting in clinical guides that stress the need for adequate vitD supplementation. In addition, data are accumulating on its relevance to cardiovascular disease, cancer, cognition and other health domains. Recent studies and meta-analyses seem to lower this enthusiasm concerning the expected good outcomes of higher vitD levels in regard to reduction of risk for major chronic diseases in the general population. However, data are more supportive on various benefits in the case of vitamin D deficiency states, especially in older people. The following article is a short review of the latest developments in this regard.


Assuntos
Promoção da Saúde , Vitamina D , Envelhecimento , Densidade Óssea , Doenças Cardiovasculares/prevenção & controle , Doença Crônica/prevenção & controle , Cognição , Suplementos Nutricionais , Feminino , Fraturas Ósseas/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/prevenção & controle , Vitamina D/administração & dosagem , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D
20.
Climacteric ; 17(5): 580-2, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24502814

RESUMO

Aging is the strongest risk factor for cognitive decline. The perimenopausal period puts women in a more vulnerable state in regard to certain functions such as memory. Also, the Women's Health Initiative Memory Study (WHIMS) pointed at some cognitive adverse effects of postmenopausal hormone therapy, but these results were not relevant for the peri- and early menopause since WHIMS recruited women above the age of 65 years. The 'window of opportunity' theory, pointing at potential protective effects of postmenopausal hormone therapy in the early menopause, mainly applies to coronary artery disease, but clinical data on neuroprotection by estrogen are not consistent. In view of a recent publication, the following article discusses the issue of menopause and cognitive decline, with a focus on possible associations with surgical menopause.


Assuntos
Transtornos Cognitivos/etiologia , Menopausa Precoce/psicologia , Complicações Pós-Operatórias , Adulto , Fatores Etários , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/etiologia , Doença de Alzheimer/prevenção & controle , Cognição/efeitos dos fármacos , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/prevenção & controle , Terapia de Reposição de Estrogênios/efeitos adversos , Feminino , Humanos , Menopausa Precoce/efeitos dos fármacos , Pessoa de Meia-Idade , Saúde da Mulher
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