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1.
Hum Reprod ; 38(9): 1784-1788, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37470235

RESUMO

STUDY QUESTION: Can anti-Müllerian hormone (AMH) help predict how many oocytes will be retrieved following double stimulation (DuoStim)? SUMMARY ANSWER: A simple clinical tool can use serum AMH values to predict ovarian response following DuoStim in IVF cycles. WHAT IS ALREADY KNOWN: The knowledge that multiple follicular waves arise during a single ovarian cycle has led to the introduction of unconventional ovarian stimulation protocols. The DuoStim protocol involves two successive ovarian stimulations performed during a single ovarian cycle and has been proposed as an approach for patients with poor ovarian response and for medical fertility preservation. As AMH has been used as a marker of ovarian reserve and stimulation response, the current study aimed to investigate the diagnostic performance of AMH in predicting the number of retrieved oocytes following DuoStim. STUDY DESIGN, SIZE, DURATION: This is a retrospective observational study involving 116 patients who received IVF treatment from January 2021 to September 2022. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study was conducted at a private IVF centre. Only patients who had their AMH measured prior to treatment and had complete patient records regarding their clinical and IVF/ICSI cycle characteristics were included. The primary outcome was the correlation between AMH values and the number of oocytes retrieved following DuoStim. Parametric and non-parametric tests were used to compare baseline characteristics and outcomes. Spearman's R was used to analyse correlations between variables, while the C statistic was used to calculate the diagnostic performance of AMH. MAIN RESULTS AND THE ROLE OF CHANCE: AMH levels were significantly correlated with the total number of oocytes retrieved after the DuoStim (R 0.61; CI 0.44-0.70; P < 0.0001). The difference in the total number of oocytes retrieved between the first (median 4 oocytes, interquartile range (IQR) 2-6) and second (median 6 oocytes, IQR 3.2-8) stimulation was statistically significant (P < 0.0001). However, there was no significant difference in the number of mature oocytes that were retrieved (median of 3 and 4 in the first and second stimulations, respectively). After the first stimulation, 68% of patients had at least one blastocyst available, while after the second stimulation, 74% did (NS). Based on linear regression, each 0.25 ng/ml increase in basal AMH corresponds to one additional oocyte recovered at the end of both stimulations (R2: 0.32, P < 0.0001). LIMITATIONS, REASONS FOR CAUTION: The results are limited owing to the observational nature of the study and the number of participants. WIDER IMPLICATIONS OF THE FINDINGS: Counselling infertile couples regarding the intermediate outcome of IVF (i.e. number of retrieved oocytes) is one of the most demanding tasks that clinicians face. To our knowledge, this is the first study that provides an easy-to-use clinical tool that enables the quantitative prediction of ovarian response following DuoStim, based on serum AMH values. STUDY FUNDING/COMPETING INTEREST(S): No external funding was obtained for this study. The authors declare no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Infertilidade , Oócitos , Feminino , Humanos , Fertilização in vitro , Ovário , Indução da Ovulação/métodos , Estudos Retrospectivos
2.
J Assist Reprod Genet ; 37(6): 1379-1385, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32363563

RESUMO

PURPOSE: To investigate the clinical efficacy of a "Universal Warming" protocol, based on subsequent steps with 1 M and 0.5 M concentration of extracellular cryoprotectant (ECCP), on shipped oocytes. Oocytes are vitrified using different brands of ready-to-use kits which recommend that the use of their own warming kit and combining different vitrification/warming kits may have legal consequences for assisted reproductive (AR) centers, until this practice has been validated with clinical studies. METHODS: Retrospective multi-center transnational observational study. Number of oocytes warmed 1.898. Vitrification performed with vitrification kit (Kitazato, Japan); warming carried out randomly with two different kits: Kitazato warming kit and Vit Kit®-Thaw (FujiFilm Irvine, USA). Warmed oocytes were assigned to 2 groups: KK (Kitazato/Kitazato) 939, and KI (Kitazato/Irvine) 959. Primary endpoint: survival rate. Secondary endpoints: fertilization rate; blastulation rate; implantation rate; live birth rate. RESULTS: Survival was comparable between the groups: 84.6% (795/939) in group KK vs 82.1% (787/959) in group KI. Fertilization rate was lower (P = 0.027) in group KK (75.7%-602/795) than in group KI (80.4%-633/787). Blastulation and implantation and live birth rates were all statistically comparable between the study groups: blastulation rate was 58.5% (352/602) vs 57.8% (366/633); implantation rate was 41.5% (80/193) vs 45.9% (84/183); live birth rate was 52.5% (62/118) in KK and 45.0% (54/120) in KI. CONCLUSION: The use of this "Universal Warming" protocol simplifies vitrified oocyte exchange between AR centers in different countries, and overcomes potential regulatory/commercial/availability differences affecting clinical practice.


Assuntos
Coeficiente de Natalidade , Implantação do Embrião/fisiologia , Transferência Embrionária , Oócitos/crescimento & desenvolvimento , Adulto , Criopreservação , Feminino , Fertilização in vitro , Humanos , Japão , Nascido Vivo/epidemiologia , Doação de Oócitos , Recuperação de Oócitos/métodos , Gravidez , Taxa de Gravidez , Vitrificação
3.
Ann Oncol ; 24(7): 1859-1866, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23532115

RESUMO

BACKGROUND: Postsurgical treatment of ductal intraepithelial neoplasia (DIN) with standard doses of tamoxifen has not reached a consensus yet. Given positive results of low-dose tamoxifen on breast cancer biomarkers modulation, we analyzed a large cohort of DIN patients treated with low-dose tamoxifen or no treatment as per institutional guidelines. PATIENTS AND METHODS: All consecutive women operated on at the European Institute of Oncology for estrogen receptor (ER)-positive DIN (474 treated with low-dose tamoxifen and 509 untreated patients) were followed up for a median of 7 years. RESULTS: Compared with untreated patients, a significant 30% reduction in breast cancer risk was observed on low-dose tamoxifen with an adjusted hazard ratio (HR) = 0.70 [95% confidence interval (CI) 0.51-0.94], with a greater benefit in postmenopausal (HR = 0.57; 95% CI 0.34-0.94) than in premenopausal women (HR = 0.79; 95% CI 0.54-1.17). Treated patients with ER and progesterone receptor (PgR) >50% DIN had a lower incidence of breast events than untreated ones (HR = 0.61; 95% CI 0.40-0.94), whereas no protective effect has been observed in patients with ER or PgR <50% DIN. Drug discontinuation resulted in a doubled risk of recurrence in premenopausal women only (HR = 1.95; 95% CI 0.98-3.89). No excess of endometrial cancer occurred. CONCLUSIONS: Low-dose tamoxifen is a promising and safe strategy for highly endocrine responsive DIN. Treatment adherence is crucial in premenopausal women. A definitive trial is ongoing.


Assuntos
Antineoplásicos Hormonais/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Carcinoma in Situ/tratamento farmacológico , Carcinoma Ductal de Mama/tratamento farmacológico , Tamoxifeno/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma in Situ/patologia , Carcinoma in Situ/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Quimioterapia Adjuvante , Ensaios Clínicos como Assunto , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Mastectomia Segmentar , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Estudos Retrospectivos , Resultado do Tratamento
4.
Exp Gerontol ; 43(2): 74-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17697759

RESUMO

Starting from young to very old subjects, aging is associated with a progressive remodeling. Such an age-dependent remodeling process mainly affects anthropometrics, endocrine and thus, also metabolic factors. Interestingly, it occurs in some individuals successfully, while in others unsuccessfully. Centenarians in good health conditions are a very selected group of subjects representing an exceptional condition. Why the centenarians reach the extreme human life span is still unknown. Thus, in this article we will review the best known causes of age-related insulin resistance, outline the main metabolic differences between aged subjects and healthy centenarians, underline the clinical relevance of insulin resistance in the elderly and finally, we will try to propose a unifying hypothesis for explaining the development of insulin resistance with aging.


Assuntos
Adaptação Fisiológica , Resistência à Insulina , Longevidade/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Constituição Corporal/fisiologia , Feminino , Humanos , Masculino , Estresse Oxidativo , Caracteres Sexuais
5.
Clin Endocrinol (Oxf) ; 60(5): 637-43, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15104569

RESUMO

BACKGROUND: This study was aimed to evaluate the effect of different recombinant LH (rLH) doses on the ovarian outcome of normogonadotrophic women with an initial inadequate response to recombinant FSH (rFSH) after pituitary downregulation. METHODS: Only women undergoing a 'long protocol' with a GnRH-agonist followed by rFSH administration were enrolled. On the eighth day of stimulation, 46 patients with serum E2 levels < 180 pg/ml and with no follicle > 10 mm were randomized in two groups to receive a supplementation with a daily rLH dose of 75 (group A) or 150 IU (group B), respectively. Forty-six normal responders continuing their monotherapy with rFSH formed the control group (C). RESULTS: The mean number of oocytes retrieved and the percentage of mature oocytes in the group B (9.65 +/- 2.16, 79.0%) were comparable with those observed in the group C (10.65 +/- 2.8, 82.5%) and significantly higher when compared with the group A (6.39 +/- 1.53, 65.7%). The mean number of ampoules of rLH was significantly higher in the group B (14.4 +/- 2.0 vs. 9.65 +/- 1.1), whereas these patients received a significantly lower mean number of rFSH ampoules (44.6 +/- 7.4 vs. 36.1 +/- 3.8). Seven (30.4%), 9 (39.1%) and 22 (47.8%) pregnancies were achieved in the groups A, B and C, respectively. CONCLUSIONS: These results suggest that patients with initial inadequate responses to rFSH after pituitary downregulation benefit from the addition of a daily dose of 150 IU of rLH, starting from the eighth day of stimulation.


Assuntos
Hormônio Foliculoestimulante/uso terapêutico , Hormônio Luteinizante/uso terapêutico , Indução da Ovulação/métodos , Adulto , Análise de Variância , Esquema de Medicação , Feminino , Fertilização in vitro , Humanos , Testes de Função Ovariana , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico
6.
Clin Nephrol ; 59(5): 388-90, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12779103

RESUMO

Neurotoxicity is an unusual complication of cephalosporin therapy. Only few cases of neurotoxicity induced by Cefepime have been described and probably the frequency of Cefepime-induced status epilepticus is underestimated. We report a case of an 82 year-old male, ESRD patient on chronic hemodialysis program affected by pneumonia, who received a treatment with intravenous Cefepime (1 g/day) and developed a seizure 4 days after the starting antibiotic therapy. Cefepime-induced neurotoxicity was suspected and its administration was immediately discontinued. In order to increase Cefepime clearance a hemodialysis session was urgently started and an improvement of his conscious level was observed. On the following day, after a second hemodialysis session his clinical condition and the status of neurotoxicity were completely recovered. The patient was discharged from the hospital in stable clinical condition one week later. At variance with the cases previously reported, the daily dose of Cefepime administrated to our patient was 50% lower and respected drug prescription dosage. Thus, we speculate on the hypothesis that advanced age of our patient and metabolic encephalopathy induced by chronic uremia made him more sensitive to the neurotoxicity induced by the drug. In conclusion, our case suggests that, in very old patients on long-term hemodialysis, it should be considered, to avoid neurotoxicity, to monitor the clinical neurological status, to use Cefepime at lower dosage than that allowed in patients with severe renal impairment (1 g/day) and, when possible, to evaluate Cefepime plasma levels. However, in these patients, other agents of the same class should be considered such as Cefotaxime and Ceftriaxone which are characterized by both an hepatic and renal excretion. In alternative to cephalosporins, antibiotics with the same action spectrum in the absence of neurological toxicity (i.e. Meropenem) should be recommended.


Assuntos
Cefalosporinas/efeitos adversos , Confusão/induzido quimicamente , Epilepsia Tônico-Clônica/induzido quimicamente , Pneumonia/tratamento farmacológico , Idoso , Cefepima , Humanos , Falência Renal Crônica/terapia , Masculino , Diálise Renal
7.
Hum Reprod ; 16(9): 1875-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11527891

RESUMO

BACKGROUND: The aim of this study was to investigate the effects of adding human menopausal gonadotrophin (HMG) during controlled ovarian stimulation in normoovulatory normogonadotrophic patients showing an initial suboptimal response to a standardized long protocol therapy with recombinant FSH (rFSH) (300 IU/day). METHODS: A total of 43 such patients were randomized in two groups. In Group A, 150 IU rFSH was substituted by 150 IU HMG after day 8 of stimulation. The stimulation protocol of Group B involved a simple increase of the daily rFSH dose to 375 IU after day 8. A total of 40 BMI and age matched patients with an optimal ovarian response formed the control group (Group C). RESULTS: The mean Group A serum concentration of oestradiol on the day of HCG administration and average number of oocytes retrieved were significantly higher than Group B (P < 0.001) and equivalent to Group C. A total of 10 pregnancies (50%) in Group A, 8 (34.8%) in Group B and 19 (47.5%) in the control group were achieved. CONCLUSIONS: The data suggest that LH supplementation improves the ovarian outcome in patients characterized by an inadequate initial response to rFSH therapy in a long protocol.


Assuntos
Fármacos para a Fertilidade Feminina/uso terapêutico , Fertilização in vitro , Hormônio Foliculoestimulante/uso terapêutico , Gonadotropinas/sangue , Menotropinas/uso terapêutico , Hipófise/metabolismo , Terapia de Salvação , Adulto , Gonadotropina Coriônica/uso terapêutico , Regulação para Baixo , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Oócitos , Gravidez , Taxa de Gravidez , Proteínas Recombinantes/uso terapêutico , Manejo de Espécimes
8.
J Am Geriatr Soc ; 49(5): 610-4, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11380755

RESUMO

OBJECTIVES: To evaluate the possible relationship between angiotensin-converting enzyme (ACE) insertion-deletion (ID) genotype and insulin resistance in a population of healthy older Italian subjects. DESIGN: Prospective recruitment of a convenience sample. PARTICIPANTS: One hundred twenty-five subjects age 62 to 105 in good health and not taking any drug known to interfere with glucose metabolism. RESULTS: In the sample population, the relative frequencies of the ACE genotypes deletion-deletion (DD) (0.424), ID (0.400), and insertion-insertion (II) (0.176) were not significantly different from values predicted by Hardy-Weinberg equilibrium. The genotype distribution was similar in men and women. Subjects carrying the II genotype had a higher FPG (P <.001) and FPI (P <.001) than did subjects with DD or ID genotype. Subjects with II genotype also had a significantly higher HOMA index than did subjects with DD or ID genotype (P for trend <.002). In a multivariate stepwise regression analysis, the ACE ID polymorphism was significantly and independently associated with the HOMA index (P <.001). The same result was confirmed performing multivariate analysis in the younger group and centenarians separately. CONCLUSIONS: In an older population, the presence of II ACE genotype is associated with a high degree of insulin resistance independent of other anthropometric variables known to interfere with insulin action; this association is significant in both the younger subjects and the centenarians.


Assuntos
Deleção de Genes , Resistência à Insulina/genética , Mutagênese Insercional/genética , Peptidil Dipeptidase A/genética , Polimorfismo Genético/genética , Distribuição por Idade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antropometria , Glicemia/análise , Índice de Massa Corporal , Jejum , Feminino , Frequência do Gene/genética , Genótipo , Teste de Tolerância a Glucose , Homeostase , Humanos , Insulina/sangue , Itália , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Estudos Prospectivos , Análise de Regressão , Fatores de Risco
9.
Am J Hypertens ; 14(2): 114-20, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11243301

RESUMO

Left ventricular (LV) hypertrophy is an important predictor of cardiovascular morbidity and mortality. Hemodynamic factors, such as 24-h blood pressure (BP) values, are responsible for left ventricular hypertrophy in hypertensives. On the other hand, some metabolic factors have also been suggested to affect LV mass and geometry. In particular, plasma leptin concentrations have been found associated to LV myocardial growth. Because chronic leptin infusion stimulates sympathetic nervous system activity and increases BP levels, the role of 24-h BP values on leptin-related changes in myocardial wall geometry cannot be ruled out. Thus, the aim of our study was to evaluate whether the relationship between plasma leptin levels and LV wall thickness is mediated by 24-h BP values in hypertensive male patients. Thirty-six newly diagnosed hypertensive patients underwent Doppler echocardiographic examination, 24-h ambulatory BP recording, and metabolic (euglycemic hyperinsulinemic glucose clamp and fasting plasma leptin levels) measurements. Left ventricular mass correlated positively only with ambulatory diastolic BP (DBP) values, whereas the indices of myocardial wall growth such as interventricular septum thickness and sum of wall thickness (ie, septal + posterior wall thickness) correlated either with 24 h, daytime, or nighttime DBP, as well as with fasting plasma glucose, fasting plasma leptin, and insulin action after adjustment for age, body mass index (BMI), and waist/hip ratio (WHR). In contrast, plasma leptin concentration did not correlate with clinical and ambulatory BP values. A multiple linear regression analysis allowed to investigate the independent role of main anthropometric and cardiovascular covariates on the sum of wall thickness variability. A model that includes age, BMI, WHR, fasting plasma leptin concentration, plasma Na+ concentration, insulin action, and nighttime DBP explained 68% of the sum of wall thickness variability. In such a model, plasma leptin concentration (P < .001), insulin action (P < .029), and nighttime DBP (P < .002) were significantly and independently associated with myocardial wall thickness. In conclusion, our study demonstrates that in hypertensive men fasting plasma leptin levels are determinant of myocardial wall thickness independently of 24-h BP values.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Pressão Sanguínea , Ecocardiografia , Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Insulina/fisiologia , Leptina/sangue , Adulto , Humanos , Hipertensão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Concentração Osmolar
10.
J Clin Endocrinol Metab ; 86(3): 1078-82, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11238489

RESUMO

The possible relationship between paraoxonase (PON) gene polymorphism and brachial reactivity in healthy adult subjects in the presence of acute hypertriglyceridemia (HT), as a prooxidant factor, was investigated. In 101 healthy subjects the response to flow- induced vasodilatation was measured before and after Intralipid infusion. In the same subjects the A/B PON polymorphism was detected. The frequency was 0.545 for AA genotype, 0.356 for the AB genotype, and 0.099 for the BB genotype. At baseline all genotype groups had a similar increase in brachial artery diameter and flow. After Intralipid infusion, subjects sharing the BB genotype had a significant decrease vs. baseline values in changes in brachial artery diameter (P for trend < 0.001 vs. the other genotypes), but not in flow. In a subgroup of 55 subjects distributed among the 3 PON genotypes the same study protocol was repeated by buccal nitroglycerine administration to study the endothelium-independent vasodilatation. Again, subjects with the BB genotype had the worse vasodilation (P for trend < 0.001). Furthermore, subjects sharing the BB genotype had the lowest endothelium-independent and -dependent changes in diameter (P for trend < 0.001 vs. the other genotypes) independently of gender ratio, basal plasma triglycerides concentrations, and changes in plasma triglycerides concentrations. In conclusion, our study demonstrates that transient HT decreases vascular reactivity more in subjects with the PON BB genotype than in those with the other PON genotypes.


Assuntos
Artéria Braquial/fisiopatologia , Esterases/genética , Genótipo , Hipertrigliceridemia/fisiopatologia , Polimorfismo Genético , Adulto , Arildialquilfosfatase , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Constrição , Emulsões Gordurosas Intravenosas , Ácidos Graxos não Esterificados/sangue , Feminino , Humanos , Hiperemia/etiologia , Hiperemia/fisiopatologia , Hipertrigliceridemia/genética , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue , Vasodilatação
11.
Nephrol Dial Transplant ; 16(3): 566-73, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11239033

RESUMO

BACKGROUND: Heart rate variability parameters were evaluated in 10 healthy subjects, 10 type II diabetic patients and 20 end-stage renal disease (ESRD) patients (11 non-diabetic and nine type II diabetic) undergoing chronic haemodialysis. The study was divided in two phases. METHODS: In the first phase all subjects underwent electrocardiograph (ECG) recording under baseline conditions. In the second phase only ESRD patients underwent haemodialysis and ECG recording. On the day of dialysis and ECG recording the ECG recording was started 1 h before the haemodialysis session (pre-dialytic period), and continued throughout the dialysis (dialytic period), until the morning after (post-dialytic period). RESULTS: Compared with ESRD patients, non-ESRD patients showed the lowest cardiac sympathetic activity. Diabetic patients compared to non-diabetic patients showed a prevalence of cardiac sympathetic activity in the pre-dialytic period (P < 0.01). During the dialytic period in comparison with the pre-dialytic one, a further increase in cardiac sympathetic activity was observed in both diabetic and non-diabetic ESRD patients (P < 0.001). However, in the post-dialysis period the cardiac autonomic nervous system activity remained at the pre-dialytic condition in the diabetic group. In contrast, in the non-diabetic group the cardiac autonomic balance shifted towards a parasympathetic prevalence in the post-dialytic period (P < 0.01). In addition, a significant correlation was found between changes in heart rate variability and changes in plasma urea concentration in the non-diabetic group only (r = 0.65; P < 0.03). CONCLUSIONS: Non-insulin-dependent diabetic uraemic patients undergoing a chronic haemodialysis programme have a severe impairment of heart rate variability. This is probably due to autonomic neuropathy related to the effects of both diabetes and chronic uraemic conditions. In non-diabetic haemodialysis patients uraemia causes similar but reversible changes in heart rate variability compared with the changes caused by diabetes.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Nefropatias Diabéticas/fisiopatologia , Nefropatias Diabéticas/terapia , Frequência Cardíaca , Falência Renal Crônica/fisiopatologia , Falência Renal Crônica/terapia , Diálise Renal , Sistema Nervoso Autônomo/fisiopatologia , Eletrocardiografia , Feminino , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Sistema Nervoso Simpático/fisiopatologia , Fatores de Tempo , Uremia/fisiopatologia , Uremia/terapia
12.
Am J Clin Nutr ; 72(3): 723-30, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10966890

RESUMO

BACKGROUND: Fatty acids have been shown to stimulate the sympathetic nervous system in rats. Power spectral analysis of heart rate variability (HRV) is a safe and useful tool with which to evaluate cardiac autonomic nervous system (ANS) activity. Whether changes in plasma fatty acid concentrations affect the sympathetic nervous system or HRV in humans is unknown. OBJECTIVE: We investigated the possible changes in HRV after a significant increase in plasma fatty acid concentration. DESIGN: Subjects were randomly assigned to receive an infusion of lipid emulsion (10% triacylglycerol emulsion for 180 min) + heparin (a bolus of 200 U followed by 0.2 U*min(-)(1)*kg body wt(-)(1); n = 20) or 0.9% NaCl (for 180 min; n = 10). RESULTS: Lipid emulsion + heparin infusion was associated with a rise in plasma epinephrine and norepinephrine concentrations. The rise in plasma fatty acid concentration was associated with a significant decline in the RR interval (P: < 0.03) and in total power (P: < 0.03). Analysis of the different components of HRV showed that lipid emulsion + heparin infusion stimulated low- frequency (LF) components (P: < 0.03 at the second hour and P: < 0. 01 at the third hour) and inhibited high-frequency (HF) components (P: < 0.03 at the second and third hours). Consequently, the LF-HF ratio was significantly stimulated (P: < 0.03 at the second hour and P: < 0.01 at the third hour). Such results persisted, although attenuated, when the study was repeated in association with a propranolol infusion (n = 8). CONCLUSION: Elevated plasma fatty acid concentrations may stimulate cardiac autonomic nervous system activity.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Ácidos Graxos/sangue , Sistema de Condução Cardíaco/fisiologia , Adulto , Antiarrítmicos/farmacologia , Emulsões , Epinefrina/sangue , Fibrinolíticos/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Hemodinâmica/efeitos dos fármacos , Heparina/farmacologia , Hormônios/sangue , Humanos , Lipídeos/farmacologia , Norepinefrina/sangue , Concentração Osmolar , Propranolol/farmacologia , Valores de Referência
13.
Arch Gerontol Geriatr ; 31(1): 35-42, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10989162

RESUMO

The objective of this study was to evaluate the relationship of whole blood viscosity and its major determinants (plasma fibrinogen level, hematocrit, hemoglobin and blood cell count) to advancing age. A total of 249 subjects (mean age 49.9+/-21.5; range 19-102 years) were included in the study. They were divided into three groups, (A) <30 years of age, n, 58; (B) 30-60 years, n, 107; (C) >60 years, n, 84. Whole blood viscosity at two different rates of shear (450 and 45 s(-1)) was evaluated using a cone-plate digital viscosimeter. The hematological parameters (hematocrit, hemoglobin and blood cell count) were evaluated using an automatic Coulter Counter. Plasma fibrinogen concentration was measured by a clotting method. When both sexes are considered together, whole blood viscosity shows no significant difference among age groups. Plasma fibrinogen concentration significantly increases with age (P<0.001); hemoglobin, red blood cell count and platelet count, on contrary, are significantly lower in aged group. In the male sex, blood viscosity at higher shear rate (450 s(-1)) negatively correlates with advancing age (P<0.005). The age-related decrease of hematocrit value in the male sex accounts for this occurrence.

14.
J Clin Endocrinol Metab ; 85(5): 1810-4, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10843157

RESUMO

Previous studies have shown that leptin stimulates sympathetic nervous system; heart rate variability (HRV) is a widely used technique for assessing the sympathovagal balance at the cardiac level. The aim of our study was to investigate a possible relationship between plasma leptin levels and the autonomic regulation using spectral analysis of HRV. In 120 healthy nonobese subjects the plasma leptin concentration was determined, and HRV was recorded at baseline and during tilt. All subjects were categorized in quartiles of plasma leptin concentration. Analysis of data showed a significant increase in body mass index, body fat, fasting plasma insulin, triglyceride concentration, and homeostatic model assessment values throughout the different quartiles of plasma leptin concentration. Concerning cardiovascular parameters, heart rate, arterial blood pressures, and RR intervals were not significantly different among the quartiles. Total power and high frequency (HF) in normalized units were significantly decreased, whereas low frequency (LF) normalized units was progressively increased from the first to the fourth quartile. Thus, the LF/HF ratio rose gradually and significantly from the lowest to the highest quartile. Such results were independent of the body fat estimate (P < 0.03 for the trend). The change in the LF/HF ratio was significantly enhanced during tilt (P < 0.001 vs. rest values for all quartiles); the effect was stronger in subjects in the fourth quartile of plasma leptin concentration (P < 0.005 for the trend). The latter parameter was also independent of body fat content and distribution (P < 0.01). Our study shows that increasing fasting plasma leptin concentrations are associated with a shift of the sympathovagal balance toward a progressive increase in sympathetic activation and an increased response to orthostatic stimulus in nonobese subjects with different body fat contents.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Peso Corporal/fisiologia , Frequência Cardíaca/fisiologia , Coração/inervação , Leptina/sangue , Tecido Adiposo/anatomia & histologia , Adulto , Pressão Sanguínea , Composição Corporal , Índice de Massa Corporal , Epinefrina/sangue , Homeostase , Humanos , Insulina/sangue , Lipoproteínas/sangue , Masculino , Norepinefrina/sangue , Triglicerídeos/sangue
15.
Eur J Clin Invest ; 30(4): 277-84, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10759874

RESUMO

BACKGROUND: Spectral analysis of heart rate variability (HRV) investigates the cardiac autonomic nervous system (ANS) activity. In particular, low frequency/high frequency (LF/HF) is considered an index of cardiac sympatho-vagal balance and is stimulated by glucose ingestion in healthy subjects. No studies have evaluated the effect of glucose ingestion on cardiac ANS in centenarians. MATERIALS AND METHODS: In 30 healthy centenarians (HC) and 25 aged subjects (AS) power spectral analysis of HRV was investigated during an oral glucose ingestion. RESULTS: Glucose ingestion rose LF/HF ratio in both groups studied. Such stimulatory effects were restrained to the first 60 min of the study. Independent of age, gender, body mass index (BMI) and fasting plasma norepinephrine and FT3 concentrations, HC had basal total power (1318 +/- 546 vs. 1918 +/- 818 msec2, P < 0.01), lower low frequency (LF) (33 +/- 21 vs. 50 +/- 11 n.u., P < 0. 03), and higher high frequency (HF) (74 +/- 18 vs. 43 +/- 15 n.u., P < 0.05) than AS. Consequently, LF/HF ratio (0.43 +/- 0.07 vs. 0.91 +/- 0.05, P < 0.02) was also lower in HC than in AS. In AS, but not in HC, the baseline LF/HF ratio correlated significantly with BMI (r = 0.48, P < 0.01), waist-hip-ratio (WHR) (r = 0.45, P < 0.02), fasting plasma insulin (r = 0.49, P < 0.01) and norepinephrine (r = 0.57, P < 0.02) concentration. Glucose ingestion was associated with a significant rise in LF/HF ratio in both groups studied but per cent changes in glucose mediated stimulation of LF/HF was lower in HC than in AS. In a control study, water administration did not affect power spectral parameters of HRV. CONCLUSION: Our study demonstrates that basal- and glucose-stimulated LF/HF, an indirect index of cardiac sympatho-vagal balance, are lower in HC than in AS.


Assuntos
Idoso de 80 Anos ou mais/fisiologia , Idoso/fisiologia , Glucose/farmacologia , Frequência Cardíaca/fisiologia , Coração/inervação , Insulina/sangue , Sistema Nervoso Autônomo/efeitos dos fármacos , Sistema Nervoso Autônomo/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Colesterol/sangue , Carboidratos da Dieta , Epinefrina/sangue , Ácidos Graxos não Esterificados/sangue , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Leptina/sangue , Masculino , Norepinefrina/sangue , Fatores de Tempo , Triglicerídeos/sangue
16.
Atherosclerosis ; 150(1): 121-7, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10781642

RESUMO

One hundred and ninety-five aged (mean age: 67+/-4.8 years), non-insulin dependent diabetic patients underwent a randomised single-blind study for investigating the effect of statin administration on insulin resistance and respiratory quotient. After 4 weeks run-in period, all patients were randomised in three groups: placebo (n=67), simvastatin (10 mg/day) (n=61) and atorvastatin (5 mg/day) (n=67). Each treatment period lasted 8 weeks. At the beginning, after the run-in and at the end of the study, insulin resistance was assessed by homeostasis model assessment (HOMA) index, while respiratory quotient (Rq) was evaluated by indirect calorimetry. Statins versus placebo significantly lowered plasma total, LDL-, HDL-cholesterol and triglyceride concentrations and improved insulin resistance and Rq and metabolic control. Atorvastatin had a greater effect than simvastatin on plasma triglyceride concentration (-26.3+/-3.1 vs. -19.7+/-2.8%, P<0.03), HOMA index (-13.1+/-0.6 vs. -9.1+/-0.9%, P<0.05), Rq (5.9+/-0.4 vs. 3.1+/-0.5%, P<0.05) and glycosylated haemoglobin (-11.2+/-0.3 vs. -7. 1+/-0.4%, P<0.05). In the whole group of subjects (n=195) and at the end of the study, changes in plasma triglyceride concentrations were significantly correlated with the change in the HOMA index (r=0.44, P<0.001) and age and BMI adjusted-Rq (r=-0.32, P<0.005). Multivariate analyses demonstrated that decline in plasma triglyceride concentration was a significant determinant for explaining the effect of statin on insulin resistance and Rq. In conclusion our study demonstrates that statin administration is useful for controlling dyslipidemia in NIDDM patients and for improving the metabolic control. With regard to this latter aim, atorvastatin seems to be more powerful than simvastatin.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Metabolismo Energético , Ácidos Heptanoicos/uso terapêutico , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Resistência à Insulina , Pirróis/uso terapêutico , Sinvastatina/uso terapêutico , Idoso , Atorvastatina , Calorimetria Indireta , Dióxido de Carbono/metabolismo , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Hemoglobinas Glicadas/análise , Humanos , Hiperlipidemias/sangue , Hiperlipidemias/complicações , Masculino , Consumo de Oxigênio , Método Simples-Cego , Triglicerídeos/sangue
17.
Clin Sci (Lond) ; 98(2): 129-36, 2000 02.
Artigo em Inglês | MEDLINE | ID: mdl-10657266

RESUMO

The effects of insulin infusion on cardiac autonomic nervous system (ANS) activity were investigated in healthy subjects (n=15) and in patients with various types of insulin-resistance, such as obese subjects (n=20) and those with hypertension (n=15) or type II (non-insulin-dependent) diabetes (n=22). Healthy subjects and patients underwent euglycaemic hyperinsulinaemic glucose clamp, and cardiac ANS and haemodynamic changes were investigated by continuous recording of heart rate variability by the Holter technique and by venous occlusion plethysmography respectively. At baseline, healthy subjects had the highest values for total spectral power and the low-frequency (LF) component, and the lowest value for the high-frequency (HF) component. In the pooled data (n=72), the fasting plasma insulin concentration was correlated with baseline total spectral power (r=-0.37; P<0.001) and the LF/HF ratio (r=-0. 35; P<0.003). Such correlations were still significant (P<0.01 for both) after adjustment for body fat and mean arterial blood pressure. In a multivariate linear stepwise analysis (n=72), a model including body fat, waist/hip ratio, fasting plasma glucose concentration and insulin-mediated glucose uptake explained 47% of the variability of the change in the LF/HF ratio, with body fat (t=-3.11; P<0.01) and insulin-mediated glucose uptake (t=-3.48; P<0. 008) being significantly and independently associated with insulin-mediated changes in the LF/HF ratio. Insulin infusion reduced the total spectral power and increased the LF/HF ratio in healthy subjects, but not in insulin-resistant patients. In conclusion, our study demonstrates that insulin fails to stimulate cardiac ANS activity in insulin-resistant patients, independently of the causes of insulin resistance.


Assuntos
Sistema Nervoso Autônomo/efeitos dos fármacos , Coração/inervação , Hipoglicemiantes/farmacologia , Resistência à Insulina/fisiologia , Insulina/farmacologia , Análise de Variância , Glicemia/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Estatura , Peso Corporal , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/fisiopatologia , Eletrocardiografia/efeitos dos fármacos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Respiração/efeitos dos fármacos
18.
J Clin Endocrinol Metab ; 85(1): 109-15, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10634373

RESUMO

Vascular disease accounts for the majority of the clinical complications in diabetes mellitus. As an exaggerated oxidative stress degree has been postulated as the link between diabetes mellitus and endothelial function, a possible positive effect of plasma vitamin E (Vit.E) administration on brachial reactivity could be postulated. Our study aims at investigating the possible effect of chronic Vit.E administration on brachial reactivity, oxidative stress indexes, and intracellular magnesium and calcium content in type II diabetic patients free of diabetic complications. Forty adult, type II diabetic patients were enrolled in the study, which was deigned as a double blind, randomized vs. placebo trial. At baseline all patients underwent the following tests: 1) anthropometric and metabolic examinations, 2) evaluation of oxidative stress indexes, 3) intracellular magnesium and calcium measurements, and 4) determination of arterial compliance and distensibility. Then, all patients were randomly assigned to Vit.E treatment at a dose of 600 mg/day (Evion Forte; n = 20) or placebo (n = 20) over 8 weeks. At the end of this treatment period, a complete reevaluation of the patients was made. Vit.E treatment was associated with a significant improvement in the percent change in brachial artery diameter (P<0.03) and oxidative stress indexes (P< 0.005). In the Vit.E group, the percent change in brachial artery diameter correlated positively with the percent change in oxidative stress indexes (oxidized/reduced glutathione, Trolox-equivalent antioxidant capacity, thiobarbituric acid reaction products, lipid peroxides) and intracellular cation content (magnesium and calcium). After adjustment for age, sex, body mass index, and wait/hip ratio, all of these correlations remained significant (P<0.03 for all). Furthermore, adjusting for glycosylated hemoglobin, plasma total cholesterol, and homeostatic model index, brachial artery diameter was still correlated with the percent change in oxidative stress indexes (P<0.04 for all). Nevertheless, the relationship between the percent change in brachial artery diameter and oxidative stress indexes was no longer significant after adjustment for intracellular Mg and Ca2+. In conclusion, our study demonstrates that chronic administration of Vit.E improves brachial artery reactivity in patients with type II diabetes mellitus. Such an effect seems mediated by a reduction in oxidative stress and a regulation of intracellular calcium and magnesium contents.


Assuntos
Plexo Braquial/fisiopatologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Magnésio/sangue , Vitamina E/uso terapêutico , Glicemia/metabolismo , Composição Corporal/fisiologia , Cálcio/sangue , Método Duplo-Cego , Feminino , Glutationa/sangue , Humanos , Peróxidos Lipídicos/metabolismo , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
19.
Hum Reprod ; 15(1): 17-20, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10611181

RESUMO

Ovarian stimulation in cases of poor ovarian responsiveness is an important challenge in in-vitro fertilization (IVF) programmes. Despite improvements in oocyte number and quality, an ideal ovarian stimulation strategy has yet to be defined. Here, the results of ovarian stimulation with recombinant follicle stimulating hormone (rFSH) in 28 poor responders to highly purified FSH (FSH-HP) with high basal concentrations of FSH are reported. The protocols used on the FSH-HP and rFSH cycles were identical with the sole exception of the FSH preparation: triptorelin 0.1 mg/day (gonadotrophin-releasing hormone, GnRH-agonist short protocol) and the starting FSH dose of 300 IU/day were administered from day 2 of the menstrual cycle. Ovarian outcome was classified as 'normal', 'intermediate' and 'poor', depending on the number of mature oocytes retrieved and the peak serum oestradiol concentration. Nine of the 28 subjects had an intermediate ovarian response to re-stimulation with rFSH. In the 26 patients who received human chorionic gonadotrophin on both cycles, re-stimulation resulted in a significant increase (P < 0.05) in the mean number of mature oocytes (2.4 +/- 1.4 versus 1.7 +/- 0.8), mean peak oestradiol concentration (606 +/- 252 versus 443 +/- 32 pg/ml) and fertilization rate (73.0 versus 53.3%). Four pregnancies were achieved. It is concluded that rFSH in a GnRH-agonist short protocol improves the ovarian outcome in poor responders to FSH-HP with high basal concentrations of FSH.


Assuntos
Fertilização in vitro , Hormônio Foliculoestimulante/uso terapêutico , Indução da Ovulação , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/administração & dosagem , Humanos , Gravidez , Proteínas Recombinantes/uso terapêutico , Pamoato de Triptorrelina/administração & dosagem , Pamoato de Triptorrelina/uso terapêutico
20.
Hypertension ; 34(5): 1047-52, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10567180

RESUMO

Leptin, the product of the ob gene, has been shown to increase heart rate and blood pressure through a stimulation of cardiac sympathetic nervous system activity, a phenomenon also involved in the pathogenesis of left ventricular hypertrophy in hypertensives. Thus, we hypothesize that plasma leptin concentration is associated with left ventricular hypertrophy. Forty hypertensive males and 15 healthy male subjects underwent anthropometric and echocardiographic evaluations, assessment of insulin sensitivity through euglycemic glucose clamp combined with indirect calorimetry, and determination of fasting plasma leptin concentration. Fasting plasma leptin levels were higher in hypertensives than in controls (6.48+/-2.9 versus 4. 62+/-1.5 ng/mL, P<0.05); these results were unchanged after adjustment for body mass index (P<0.05). In the whole group of patients (n=55), fasting plasma leptin concentration was correlated with body mass index (r=0.46, P<0.001) and waist/hip ratio (r=0.50, P<0.001); independent of body mass index and waist/hip ratio, fasting plasma leptin concentration was correlated (n=55) with whole-body glucose disposal (r=-0.27, P<0.04), interventricular septum thickness (r=0.34, P<0.001), posterior wall thickness (r=0.38, P<0.003), and the sum of wall thicknesses (r=0.68, P<0.001). In a multivariate analysis (n=55), age, body mass index, fasting plasma leptin concentration, plasma Na(+) concentration, whole-body glucose disposal, and diastolic blood pressure explained 68% of the variability of the sum of wall thicknesses with fasting plasma leptin concentration (P<0.03), whole body glucose disposal (P<0.002), and diastolic blood pressure (P<0.001), which were significantly and independently associated with the sum of wall thicknesses. In conclusion, our study demonstrates that fasting plasma leptin levels are associated with increased myocardial wall thickness independent of body composition and blood pressure levels in hypertensives.


Assuntos
Hipertensão/complicações , Hipertrofia Ventricular Esquerda/etiologia , Resistência à Insulina , Leptina/sangue , Adulto , Índice de Massa Corporal , Ecocardiografia , Humanos , Hiperinsulinismo/sangue , Masculino , Pessoa de Meia-Idade
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