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1.
Ann Oncol ; 33(7): 685-692, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35395383

RESUMO

BACKGROUND: Sarcopenia represents an established adverse prognostic factor in cancer patients. Consequently, different means to counteract sarcopenia have been proposed to improve cancer treatment. Computed tomography (CT)-based measurements, also labor intensive, are well validated for the analysis of sarcopenia. As inflammation plays a key role in the development of sarcopenia, we here studied the role of the modified Glasgow prognostic score (mGPS), consisting of inflammation parameters plasma C-reactive protein (CRP) and albumin, to predicting sarcopenia and adipose tissue-related body composition (BC) parameters at baseline and their changes during treatment and to analyze its prognostic role in conjunction with BC parameters. PATIENTS AND METHODS: CT measurements of BC parameters were carried out at baseline and week 12 in patients with advanced gastric or esophagogastric junction cancer from the phase III EXPAND trial, undergoing first-line platinum-fluoropyrimidine chemotherapy. mGPS was calculated from baseline CRP and albumin plasma levels. Pearson correlation and Cox regression analyses were carried out. RESULTS: mGPS is strongly prognostic for overall survival (OS). Baseline mGPS is significantly correlated with baseline mean muscle attenuation (MA; P < 0.0001). Baseline mGPS did not predict a decline in muscle or adipose tissue parameters during 12 weeks of treatment and a decline in muscle or adipose tissue parameters was not prognostic for OS. MA lost its prognostic role for OS when mGPS or CRP was entered into the Cox models. Eastern Cooperative Oncology Group performance status together with CRP or mGPS remained the sole baseline prognostic factors for OS. CONCLUSIONS: Our findings support a model where tumor-mediated inflammatory response represents a strong prognostic factor, which is causally related to sarcopenia, but with no direct causal path from sarcopenia to survival. Therefore, therapeutic targeting of systemic inflammation should be further explored as a promising strategy to improve both sarcopenia and the efficacy and tolerability of cancer treatment.


Assuntos
Neoplasias , Sarcopenia , Albuminas , Composição Corporal , Junção Esofagogástrica , Humanos , Inflamação , Prognóstico , Estudos Retrospectivos
3.
J Endocrinol Invest ; 44(12): 2655-2664, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33881751

RESUMO

PURPOSE: Ghrelin is an orexigenic peptide hormone secreted in times of stress and hunger. It is deeply involved in the regulation of metabolism and energy homeostasis, promoting energy intake and inhibiting energy expenditure on a metabolic level. In this regard, it has in many ways antagonistic effect on the thyroid hormones, which increase metabolism and thus energy expenditure. While there is reasonable evidence of a negative association between ghrelin and hormones of the hypothalamic-pituitary-thyroid (HPT-) axis from studies in patients with thyroid dysfunction and small intervention studies, large-scale studies in healthy subjects are lacking. Therefore, we studied the relationship between total ghrelin serum levels and serum levels of the thyroid hormones in a large sample of euthyroid subjects. METHODS: Total ghrelin, thyroid-stimulating hormone (TSH), free thyroxine (fT4) and free triiodothyronine (fT3) were determined after an overnight fast in 1666 subjects participating in a population-based cross-sectional study ('LIFE') including 10,000 adults. 1012 subjects were included in this analysis. Multiple linear regression analyses were performed. RESULTS: FT3 was negatively associated with serum ghrelin; total sample: ß = - 0.0001, p < 0.001; men: ß = - 0.0002, p = 0.013; women: ß = - 0.0001, p = 0.010, adjusted for age, BMI, alcohol consumption, serum levels of TSH and fT4 and smoking status. No associations were found between ghrelin serum levels and serum levels of fT4 or TSH. CONCLUSION: This is to date the largest study investigating the relationship between total serum ghrelin and thyroid hormones. The results point to a complex interaction and should initiate further research.


Assuntos
Grelina , Glândula Tireoide/metabolismo , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue , Correlação de Dados , Estudos Transversais , Feminino , Grelina/sangue , Grelina/metabolismo , Voluntários Saudáveis , Homeostase/fisiologia , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Pessoa de Meia-Idade
4.
Climacteric ; 24(1): 57-63, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33395316

RESUMO

Phytoestrogens are a group of non-steroidal polyphenolic plant-based substances, commonly used for the treatment of menopause-related conditions. They have both genomic and non-genomic effects, displaying weak affinity for estrogen receptors (ER) and preferentially binding to ER-B over ER-A. However, evidence for the benefits of phytoestrogen consumption has been limited. We conducted a review of recent literature, focusing on systematic reviews and meta-analyses reporting on postreproductive health effects of phytoestrogens. While many trials concerning dietary and supplementary phytoestrogens have been conducted, evidence of clinical efficacy is heterogeneous and inconclusive. There appears to be reduction in the vasomotor symptoms of menopause with phytoestrogen intake; however, it is likely small and slow in onset. Phytoestrogens also appear to improve bone mineral density and markers of cardiovascular risk; however, there is inadequate research regarding long-term outcomes. There appear to be no harmful effects of phytoestrogens on breast, endometrial cancer or colorectal cancer and phytoestrogens intake may in fact be protective. Research regarding the effect of phytoestrogens on cognition is mixed, with most studies reporting no significant association. Overall, individual variations in the metabolism of phytoestrogens and age-related genomic effects may account for the considerable variability in the measured effects of phytoestrogens.


Assuntos
Terapia de Reposição de Estrogênios , Fitoestrógenos/uso terapêutico , Pós-Menopausa , Feminino , Humanos , Fitoestrógenos/administração & dosagem , Fitoterapia
5.
Bone ; 132: 115124, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31830529

RESUMO

BACKGROUND: We aimed to establish age- and gender-specific reference ranges for concentrations of the bone markers osteocalcin (OC), procollagen type 1 N-propeptides (PINP) and carboxy-terminal cross-linking telopeptide of type 1 collagen (CTX-I) as well as for the calciotropic hormones 25-hydroxyvitamin D [25(OH)D] and parathyroid hormone (PTH) in healthy infants, children and adolescents. In addition, the effect of age, gender, puberty and body mass index (BMI) on bone markers was investigated. METHODS: 2416 healthy subjects (5714 blood withdrawals), aged 3 months to 17 years, were included to estimate the age- and gender-dependence of reference ranges. Subsequently, measured values of the biomarkers were transformed to standard deviation scores (SDS) and their associations with age, gender and puberty were analyzed. Bone marker-SDS values of the reference cohort were compared with an obese cohort (n = 317 and 489 blood withdrawals) to analyze the effect of BMI. RESULTS: OC, PINP and CTX-I showed a distinct age- and gender-dependence with peak levels at 10 to 11 years (girls, Tanner 3) and 13 years (boys, Tanner 3-4). Children with obesity had significantly lower SDS levels for OC (-0.44), PINP (-0.27), CTX-I (-0.33), 25(OH)D (-0.43) and higher SDS levels for PTH (+0.44) than the reference cohort. CONCLUSIONS: OC, PINP and CTX-I vary with age, gender and pubertal stage. The body weight status has to be considered in the interpretation of pediatric OC, PINP, CTX-I, 25(OH)D and PTH levels. Consequences of childhood obesity on bone health should be carefully investigated in long-term studies.


Assuntos
Remodelação Óssea , Hormônio Paratireóideo , Adolescente , Biomarcadores , Criança , Colágeno Tipo I , Feminino , Humanos , Lactente , Masculino , Obesidade , Fragmentos de Peptídeos , Pró-Colágeno , Valores de Referência , Vitamina D/análogos & derivados
7.
Artigo em Alemão | MEDLINE | ID: mdl-28447138

RESUMO

Endocrine disruptive chemicals (EDCs) cause adverse health effects through interaction with endocrine systems. They are classified by chemical structure, effects on specific endocrine systems, bioaccumulation, persistence in the environment, or clinically observable effects. For research of the complex mechanisms of action in the human body, only in vitro model systems have so far been available, that have insufficient high-throughput capacity, which makes risk evaluation more difficult. In addition, in industrial nations, living people are often exposed to mixtures of substances, with various effects. The clinical importance of epigenetic changes caused by the action of EDCs during vulnerable phases of development is currently unclear. Epidemiological studies are criticized because reproducibility is not always guaranteed. Nevertheless, they remain the method of choice for the development and analysis of suitable model systems. Positive associations, in spite of sometimes conflicting results, are key in the selection of factors that can then be analysed in model systems in an unbiased way. This article depicts the mainly positive epidemiological findings for EDC-caused effects in the fields of growth and metabolism, neurocognitive development and sexual development and reproduction. As a result, there is a need for closer linkage between epidemiological studies and mechanistic research into model systems, especially focusing on the interaction of different EDCs and the consequences of prenatal and early life exposure.


Assuntos
Transtornos do Desenvolvimento Sexual/epidemiologia , Disruptores Endócrinos/intoxicação , Exposição Ambiental/estatística & dados numéricos , Transtornos do Crescimento/epidemiologia , Doenças Metabólicas/epidemiologia , Transtornos Neurocognitivos/epidemiologia , Poluição Química da Água/estatística & dados numéricos , Comorbidade , Estudos Epidemiológicos , Medicina Baseada em Evidências , Humanos , Incidência , Modelos Biológicos , Fatores de Risco
8.
Climacteric ; 20(2): 85-90, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28042728

RESUMO

Although some understanding of post-reproductive life dates back to Ancient Greece, the term 'menopause' was only introduced in the early 1800s by a French physician. Notwithstanding familiarity with the condition at that time, treatments were largely ineffective, often harmful and never evidence-based, and it was not until 100 years later with the identification and description of estrogen and progesterone that effective treatments became available. So efficacious were hormone therapies for menopausal symptoms that their prescription was often recommended for all postmenopausal women regardless of their needs, wishes or health status. For many there was benefit but for some there was harm. It was in this environment that a small group of clinicians determined to form an International Menopause Society (IMS) to conduct research into the appropriate use of hormone therapy in treating menopause symptoms, to hold regular congresses to educate colleagues and discuss research results and thus to improve the health and well-being of women in midlife and beyond. Formed in 1978, the IMS is now recognized as the global leader in its field, working towards these goals in collaboration with colleagues and other national and regional societies concerned with women's health. During that time, the IMS has been led by 13 Presidents and has conducted 15 World Congresses on the Menopause, all of which are reviewed in this paper.


Assuntos
Menopausa , Sociedades Médicas/história , Saúde da Mulher , Feminino , História do Século XX , História do Século XXI , Humanos , Pessoa de Meia-Idade
9.
Climacteric ; 19(4): 329-36, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27327421

RESUMO

Cardiovascular disease is the leading cause of morbidity and mortality in postmenopausal women. Although it is a disease of aging, vascular disease initiates much earlier in life. Thus, there is a need to be aware of the potential to prevent the development of the disease from an early age and continue this surveillance throughout life. The menopausal period and early menopause present an ideal opportunity to assess cardiovascular risk and plan accordingly. Generally in this period, women will be seen by primary health-care professionals and non-cardiovascular specialists. This review addresses female-specific risk factors that may contribute to the potential development of cardiovascular disease. It is important for all health-care professionals dealing with women in midlife and beyond to be cognisant of these risk factors and to initiate female-specific preventative measures or to refer to a cardiovascular specialist.


Assuntos
Doenças Cardiovasculares/etiologia , Menopausa , Doenças Cardiovasculares/prevenção & controle , Feminino , Humanos , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco
10.
Climacteric ; 19(2): 109-50, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26872610

RESUMO

The International Menopause Society (IMS) has produced these new 2016 recommendations on women's midlife health and menopause hormone therapy (MHT) to help guide health-care professionals in optimizing their management of women in the menopause transition and beyond. The term MHT has been used to cover therapies including estrogens, progestogens and combined regimens. For the first time, the 2016 IMS recommendations now include grades of recommendations, levels of evidence and 'good practice points', in addition to section-specific references. Where possible, the recommendations are based on and linked to the evidence that supports them, unless good-quality evidence is absent. Particular attention has been paid to published evidence from 2013 onwards, the last time the IMS recommendations were updated. Databases have been extensively searched for relevant publications using key terms specific to each specialist area within menopause physiology and medicine. Information has also been drawn from international consensus statements published by bodies such as the IMS, the European Menopause and Andropause Society and the North American Menopause Society. The recommendations have been produced by experts derived mainly from the IMS, with the assistance of key collaborators where deemed advantageous. In preparing these international recommendations, experts have taken into account geographical variations in medical care, prevalence of diseases, and country-specific attitudes of the public, medical community and health authorities towards menopause management. The variation in availability and licensing of MHT and other products has also been considered.


Assuntos
Terapia de Reposição de Estrogênios , Menopausa/fisiologia , Saúde da Mulher , Adulto , Peso Corporal , Doenças Cardiovasculares , Dieta , Medicina Baseada em Evidências , Exercício Físico , Feminino , Humanos , Estilo de Vida , MEDLINE , Menopausa Precoce , Neoplasias , Guias de Prática Clínica como Assunto , Qualidade de Vida , Sociedades Médicas
11.
Eur J Clin Nutr ; 69(1): 134-42, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25369831

RESUMO

BACKGROUND: Although postmenopausal combined hormone replacement therapy reduces the risk of hip fracture, long-term use may be associated with an increased risk of breast cancer, and in women more than 10 years after menopause it is associated with an increased risk of cardiovascular disease. Isoflavones, because of preferential binding to estrogen receptor beta, may retain the beneficial effects on bone but lessen the adverse effects on the breast. OBJECTIVE: The objective of this study was to study the effects of an isoflavone obtained from red clover (Rimostil) on bone mineral density, and on low-density lipoprotein (LDL) cholesterol. DESIGN: In a double-blind, randomized, placebo-controlled trial, 50 mg of Rimostil was given to women who were menopausal for at least 1 year. Bone mineral density of the spine, femoral neck and forearm and serum LDL cholesterol were measured at baseline and at 6-month intervals. The duration of follow-up was 2 years. RESULTS: There was no beneficial effect of Rimostil on bone density at any site. There was a 12% fall in serum LDL cholesterol in the Rimostil-treated arm, which was significantly greater than the 2% drop seen in the control arm (P=0.005).


Assuntos
LDL-Colesterol/sangue , Isoflavonas/administração & dosagem , Trifolium/química , Densidade Óssea/efeitos dos fármacos , Método Duplo-Cego , Terapia de Reposição de Estrogênios/efeitos adversos , Feminino , Humanos , Isoflavonas/efeitos adversos , Pessoa de Meia-Idade , Placebos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Pós-Menopausa
12.
Climacteric ; 17(5): 540-56, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24969415

RESUMO

Women may expect to spend more than a third of their lives after menopause. Beginning in the sixth decade, many chronic diseases will begin to emerge, which will affect both the quality and quantity of a woman's life. Thus, the onset of menopause heralds an opportunity for prevention strategies to improve the quality of life and enhance longevity. Obesity, metabolic syndrome and diabetes, cardiovascular disease, osteoporosis and osteoarthritis, cognitive decline, dementia and depression, and cancer are the major diseases of concern. Prevention strategies at menopause have to begin with screening and careful assessment for risk factors, which should also include molecular and genetic diagnostics, as these become available. Identification of certain risks will then allow directed therapy. Evidence-based prevention for the diseases noted above include lifestyle management, cessation of smoking, curtailing excessive alcohol consumption, a healthy diet and moderate exercise, as well as mentally stimulating activities. Although the most recent publications from the follow-up studies of the Women's Health Initiative do not recommend menopause hormonal therapy as a prevention strategy, these conclusions may not be fully valid for midlife women, on the basis of the existing data. For healthy women aged 50-59 years, estrogen therapy decreases coronary heart disease and all-cause mortality; this interpretation is entirely consistent with results from other randomized, controlled trials and observational studies. Thus. as part of a comprehensive strategy to prevent chronic disease after menopause, menopausal hormone therapy, particularly estrogen therapy may be considered as part of the armamentarium.


Assuntos
Doença Crônica/prevenção & controle , Pós-Menopausa , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Doença Crônica/epidemiologia , Demência/epidemiologia , Demência/etiologia , Demência/prevenção & controle , Diagnóstico Precoce , Terapia de Reposição de Estrogênios/efeitos adversos , Feminino , Humanos , Menopausa , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neoplasias/etiologia , Neoplasias/prevenção & controle , Obesidade/epidemiologia , Obesidade/etiologia , Obesidade/prevenção & controle , Osteoartrite/epidemiologia , Osteoartrite/etiologia , Osteoartrite/prevenção & controle , Osteoporose Pós-Menopausa/epidemiologia , Osteoporose Pós-Menopausa/etiologia , Osteoporose Pós-Menopausa/prevenção & controle , Qualidade de Vida , Fatores de Risco , Comportamento de Redução do Risco , Saúde da Mulher
13.
Climacteric ; 17(3): 215-22, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24654673

RESUMO

BACKGROUND: In an integrated overview of the benefits and risks of menopausal hormone therapy (HT), the Women's Health Initiative (WHI) investigators have claimed that their 'findings … do not support use of this therapy for chronic disease prevention'. In an accompanying editorial, it was claimed that 'the WHI overturned medical dogma regarding menopausal [HT]'. OBJECTIVES: To evaluate those claims. METHODS: Epidemiological criteria of causation were applied to the evidence. RESULTS: A 'global index' purporting to summarize the overall benefit versus the risk of HT was not valid, and it was biased. For coronary heart disease, an increased risk in users of estrogen plus progestogen (E + P), previously reported by the WHI, was not confirmed. The WHI study did not establish that E+ P increases the risk of breast cancer; the findings suggest that unopposed estrogen therapy (ET) does not increase the risk, and may even reduce it. The findings for stroke and pulmonary embolism were compatible with an increased risk, and among E+ P users there were credible reductions in the risk of colorectal and endometrial cancer. For E+ P and ET users, there were credible reductions in the risk of hip fracture. Under 'worst case' and 'best case' assumptions, the changes in the incidence of the outcomes attributable to HT were minor. CONCLUSIONS: Over-interpretation and misrepresentation of the WHI findings have damaged the health and well-being of menopausal women by convincing them and their health professionals that the risks of HT outweigh the benefits.


Assuntos
Neoplasias da Mama/epidemiologia , Doença das Coronárias/epidemiologia , Interpretação Estatística de Dados , Estrogênios/uso terapêutico , Terapia de Reposição Hormonal , Progestinas/uso terapêutico , Viés , Neoplasias da Mama/induzido quimicamente , Fatores de Confusão Epidemiológicos , Doença das Coronárias/induzido quimicamente , Estrogênios/efeitos adversos , Feminino , Terapia de Reposição Hormonal/efeitos adversos , Humanos , Menopausa , Progestinas/efeitos adversos , Medição de Risco
14.
Climacteric ; 17(1): 23-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23931652

RESUMO

There is a school of thought that believes that menopausal symptoms are a peculiarly 'Western' phenomenon, not experienced by women from other regions and particularly not from Asia where, it has been claimed, dietary, social and cultural factors afforded protection for women living in that region. More recently, studies conducted in multi-ethnic communities living in Western countries as well as in Asian communities have found that the menopause and its consequences are similar world-wide. Ethnic differences within Asia account for small differences in endogenous hormone levels and age at menopause between Asian and Western women, and the type of menopause symptoms and their prevalence also differ between those two communities. However, like in the West and perhaps because of a Western influence, the long-term health problems of postmenopausal women including cardiovascular disease, osteoporosis and breast cancer are of major importance to Asian women and health services in the 21st century.


Assuntos
Menopausa/etnologia , Saúde da Mulher/etnologia , Afeto , África/epidemiologia , Fatores Etários , Ásia/epidemiologia , Índice de Massa Corporal , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etnologia , Cultura , Estradiol/sangue , Europa (Continente)/epidemiologia , Feminino , Hormônio Foliculoestimulante/sangue , Fogachos/epidemiologia , Fogachos/etnologia , Humanos , Hormônio Luteinizante/sangue , Menopausa/fisiologia , Doenças Metabólicas/epidemiologia , Doenças Metabólicas/etnologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/epidemiologia , Osteoporose Pós-Menopausa/etnologia , Fatores Socioeconômicos , Estados Unidos/epidemiologia
15.
Climacteric ; 16(5): 522-35, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23931571

RESUMO

The onset of the menopause is often a time when women's concerns can act as a powerful trigger to encourage healthy modifications in lifestyle which will maintain, or improve, their general health. This document aims to help women to understand their potential risks, to encourage them to find proactive preventive strategies by modifying some of their attitudes, and to use health resources (when available) to be screened. Cancer is an important cause of death but not the primary cause of mortality. Cardio/circulatory diseases represent 35-40% of causes of death in most developed countries and 20-25% of women will die from cancers in Western Europe, Australasia, high-income North America, high-income Asia Pacific, East Asia and Southern Latin America. Breast cancer, lung cancer and colorectal cancer are prevalent in most regions of the world. Cervical cancer remains a hallmark of low access to health care. Preventive strategies (decreasing smoking and alcohol consumption, losing weight, eating a healthy diet and undertaking physical activity) and implementation of screening could help to significantly decrease the incidence of and mortality from cancer. The mortality/incidence ratio is higher in developing countries compared to high-income regions as well as in subgroups of populations in developed countries with lower socioeconomic levels. Implementation of better diagnostic methods and management of cancer according to the local resources will help to decrease the mortality rate in developing countries, and effort has to be made to decrease social inequities and improve access to health care for low-income groups. In conclusion, cancer incidence is increasing as a consequence of longer life expectancy all over the world. National health programs are mandatory to implement screening and to improve individual management. Finally, educating women so that they are aware of ways to improve their general health, to minimize their own risk factors and to identify signs of change in their own health which may be markers of impending cancer will help to reduce the burden of disease and improve the prognosis for tumors detected at an earlier stage.


Assuntos
Menopausa , Neoplasias , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/epidemiologia , Neoplasias Colorretais/epidemiologia , Dieta , Neoplasias do Endométrio/epidemiologia , Etnicidade , Feminino , Promoção da Saúde , Humanos , Renda , Expectativa de Vida , Estilo de Vida , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/etiologia , Neoplasias/mortalidade , Neoplasias/prevenção & controle , Obesidade/complicações , Neoplasias Ovarianas , Neoplasias do Colo do Útero/epidemiologia
17.
Dalton Trans ; 40(36): 9276-83, 2011 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-21837321

RESUMO

The tricarbonyl [Mn(CO)(3){HC(pz')(3)}][PF(6)] 1(+)[PF(6)](-) (pz' = 3,5-dimethylpyrazolyl) reacts with a range of P-, N- and C-donor ligands, L, in the presence of trimethylamine oxide to give [Mn(CO)(2)L{HC(pz')(3)}](+) {L = PEt(3)3(+), P(OEt)(3)4(+), P(OCH(2))(3)CEt 5(+), py 6(+), MeCN 7(+), CNBu(t)8(+) and CNXyl 9(+)}. The complex [Mn(CO)(2)(PMe(3)){HC(pz')(3)}](+)2(+) is formed by reaction of 7(+) with PMe(3). Complexes 2(+) and 6(+) were structurally characterised by X-ray diffraction methods. Reaction of 7(+) with half a molar equivalent of 4,4'-bipyridine gives a purple compound assumed to be the bridged dimer [{HC(pz')(3)}Mn(CO)(2)(µ-4,4'-bipy)Mn(CO)(2){HC(pz')(3)}](2+)10(2+). The relative electron donating ability of HC(pz')(3) has been established by comparison with the cyclopentadienyl and tris(pyrazolyl)borate analogues. Cyclic voltammetry shows that each of the complexes undergoes an irreversible oxidation. The correlation between the average carbonyl stretching frequency and the oxidation potential for complexes of P- and C-donor ligands is coincident with the correlation observed for [Mn(CO)(3-m)L(m)(η-C(5)H(5-n)Me(n))]. The data for complexes of N-donor ligands, however, are not coincident due to the presence of a node (and phase change) between the metal and the N-donor in the HOMO of the complex as suggested by preliminary DFT calculations.

18.
Climacteric ; 14(5): 515-28, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21848495

RESUMO

OBJECTIVE: An overview of the current knowledge on the etiology and treatment of vasomotor symptoms in postmenopausal women. MATERIALS AND METHODS: Acknowledged experts in the field contributed a brief assessment of their areas of interest which were combined and edited into the final manuscript. RESULTS: Women around the world experience vasomotor symptoms as they enter and complete the menopause transition. Vasomotor symptoms, specifically hot flushes, are caused by a narrowing of the thermoneutral zone in the brain. This effect, although related to estrogen withdrawal, is most likely related to changes in central nervous system neurotransmitters. Peripheral vascular reactivity is also altered in symptomatic women. Estrogen replacement therapy is the most effective treatment for hot flushes. Of the other interventions investigated, selective serotonin and selective norepinephrine reuptake inhibitors and gabapentin show efficacy greater than placebo. Objective monitoring of hot flushes indicates a robust improvement with hormone replacement therapy but little to no change with placebo. These data suggest that the subjective assessment of responses to therapy for vasomotor symptom results in inaccurate data. Hot flushes have recently been associated with increased cardiovascular risks and a lower incidence of breast cancer, but these data require confirmation. CONCLUSIONS: Vasomotor symptoms are experienced by women of all ethnic groups. They are caused by changes in the central nervous system associated with estrogen withdrawal and are best treated with estrogen replacement therapy. Objective monitoring of hot flushes indicates that placebo has little to no effect on their improvement. Subjective assessments of hot flushes in clinical trials may be inaccurate based on objective measurement of the frequency of hot flushes. Based on preliminary reports, women experiencing hot flushes have an increased risk of cardiovascular disease and a reduced incidence of breast cancer.


Assuntos
Fogachos , Menopausa/fisiologia , Adulto , Regulação da Temperatura Corporal , Encéfalo/fisiologia , Neoplasias da Mama , Doenças Cardiovasculares , Terapia de Reposição de Estrogênios , Estrogênios/fisiologia , Feminino , Fogachos/tratamento farmacológico , Fogachos/epidemiologia , Fogachos/etiologia , Humanos , Pessoa de Meia-Idade , Neurotransmissores/fisiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Sudorese , Sistema Vasomotor
19.
Climacteric ; 14(3): 302-20, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21563996
20.
Dalton Trans ; 39(25): 5899-907, 2010 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-20508889

RESUMO

Monometallic complexes of the tetrakis(pyrazolyl)borate ligand [ML(2){B(pz)(4)}] {M = Rh, Ir; L(2) = eta-cod, eta-nbd, (CO)(2), (CO)(PPh(3))} have two free pyrazolyl rings which can be coordinated to a second ML(2) unit to give the dimeric compounds [L(2)M{mu-B(pz)(4)}ML(2)](+), and to a metal halide to give heterobimetallic species [L(2)M{mu-B(pz)(4)}M'Cl(2)]. (1)H NMR spectroscopy shows that [(eta-cod)Rh{mu-B(pz)(4)}Rh(eta-cod)](+) 1(+), [(eta-nbd)Rh{mu-B(pz)(4)}Rh(eta-nbd)](+) 2(+), [(eta-cod)Ir{mu-B(pz)(4)}Ir(eta-cod)](+) 3(+) and [(CO)(2)Rh{mu-B(pz)(4)}Rh(CO)(2)](+) 4(+) are fluxional at room temperature. Cooling a solution of [(eta-cod)Rh{mu-B(pz)(4)}Rh(eta-cod)](+) 1(+) to -90 degrees C slows the fluxional process, which involves inversion of the two B-(N-N)(2)-M six-membered rings. Attempts to synthesise the asymmetric complexes [(eta-cod)Rh{mu-B(pz)(4)}Rh(eta-nbd)](+) 7(+), [(eta-cod)Rh{mu-B(pz)(4)}Ir(eta-cod)](+) 8(+) and [(eta-cod)Rh{mu-B(pz)(4)}Rh(CO)(2)](+) 9(+) produced a mixture of [L(2)M{mu-B(pz)(4)}ML(2)](+), [L'(2)M'{mu-B(pz)(4)}M'L'(2)](+) and the desired species. The heterobimetallic complexes [L(2)Rh{mu-B(pz)(4)}M'Cl(2)] (M' = Co, L(2) = eta-cod 10; M' = Co, L(2) = eta-nbd 11; M' = Co, L = CO 12; M' = Co, L(2) = (CO)(PPh(3)) 13; M' = Zn, L(2) = eta-cod 14; M' = Zn, L(2) = eta-nbd 15; M' = Pd, L(2) = eta-cod 16) possess square planar Rh(I) linked to square planar Pd(II) or tetrahedral Zn(II) and Co(II) centres. The paramagnetic Co(II) complexes give (1)H NMR spectra with signals shifted over a range of 75 ppm. The UV-Vis spectra of 10-13 show four bands, one MLCT at Rh and three d-d transitions arising from the splitting of the (4)T(1)(P) excited state due to approximate C(2v) symmetry at Co.

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