Cross-Sectional Study on the Association between Pulmonary Function and Sarcopenia in Brazilian Community-Dwelling Elderly from the Amazon Region.

OBJECTIVES: To compare the obtained and expected values of pulmonary function variables between sarcopenic and non-sarcopenic elderly; verify the association between the pulmonary function and the indicators and diagnosis of sarcopenia; and establish cut-off points for pulmonary function variables to predict sarcopenia. DESIGN: Cross-sectional study. LOCATION: Macapá, Brazil. PARTICIPANTS: community-dwelling elderly ≥ 60 years old (n=383), both sexes. MEASURES: Were evaluated according to variables of pulmonary function (spirometry) and sarcopenia, according to the EWGSOP consensus. The association between pulmonary function and sarcopenia was performed using logistic regression and cut-off points established from the ROC Curve. RESULTS: The prevalence of sarcopenia was 12.53% (n = 48). Sarcopenic individuals had significantly lower mean values for FVC, FEV1, FEF25-75% and PEF than non-sarcopenic. After adjustment, spirometric variables were inversely associated with sarcopenia (the increase by one unit of liter in FVC, FEV1 and FEF25-75% decreased the probability of sarcopenia by 59%, 67% and 39%, respectively), and the majority of these variables with the muscular strength indicator. Cut-off points, for elderly men and women, were discriminant criteria for the presence of sarcopenia: FVC (≤2.52 L and ≤1.82 L), FEV1 (≤2.1 L and ≤1.39 L), PEF (≤3.45 L/s and ≤2.93 L/s) and FEF5-75% (≤1.97 L/s and ≤1.74 L/s). CONCLUSIONS: There was loss of pulmonary function in sarcopenic elderly patients and an inverse association with the diagnosis of sarcopenia and its indicators. Cut-off points of pulmonary function variables can be used as a useful tool to discriminate sarcopenia.

Respiratory Muscle Strength as a Discriminator of Sarcopenia in Community-Dwelling Elderly: A Cross-Sectional Study.

OBJECTIVES: To compare the values obtained from maximum respiratory pressures (MRP) between sarcopenic and non-sarcopenic elderly; to verify the association of maximum respiratory pressures with sarcopenia and its indicators; and to establish cut-off points for MRP as a discriminator of sarcopenia. DESIGN: Cross-sectional study. LOCATION: Macapá, Brazil. PARTICIPANTS: Community-dwelling elderly ≥ 60 years old, both sexes. MEASURES: Evaluation of respiratory muscle strength (maximal inspiratory pressure - MIP and maximal expiratory pressure - MEP) and sarcopenia, according to the European Working Group on Sarcopenia in Older People (EWGSOP), in which the diagnosis of this condition considered the reduction of muscle mass (muscle mass index - MMI) associated with muscle strength reduction (hand grip strength - HGS) and / or impairment in physical performance (gait speed - GS). RESULTS: The sample consisted of 383 elderly individuals, with a mean age of 70.02 ± 7.3 years and a prevalence of sarcopenia of 12.53% (n = 48). Sarcopenic individuals presented significantly lower (obtained, obtained versus predicted) mean values for the maximal respiratory pressures compared to the non-sarcopenic elderly, and these were inversely associated with sarcopenia (an increase by 1 cmH2O in MIP and MEP reduced by 5% and 3%, respectively, the probability of sarcopenia). In relation to the association with the sarcopenia indicators, the increase by 1 cmH2O in MIP and MEP decreased, respectively, the probability of decreasing muscle strength (3% and 2%), GS (3% and 4%) and MMI (3 % - MIP). Cut-off points ≤60 cmH2O and ≤50 cmH2O for MEP and ≤55 cmH2O and ≤45 cmH2O for MEP, respectively for elderly men and women, served as a discriminant criterion for the presence of sarcopenia (area under the ROC curve superior to 0.70). CONCLUSIONS: Elderly patients with sarcopenia had lower MIP and MEP values when compared to non-sarcopenic individuals, and respiratory muscle strength was inversely associated with the diagnosis of sarcopenia and its indicators (HGS, gait speed and MMI). Furthermore, cut-off points for MIP and MEP can be used in clinical practice as discriminators of sarcopenia in community-dwelling elderly.

Diallel and prediction (REML/BLUP) for yield components in intervarietal maize hybrids.

Genetic improvement is essential to achieve increments in maize (Zea mays L.) grain yield components. It may be obtained through crosses, which enable to exploit the effects of intervarietal heterosis, allelic complementarity, as well as gene actions and effects. This study estimated the components of variance and genetic parameters (REML/BLUP) of an intervarietal diallel to select and predict the best genotypes for maize yield components. The experimental design was randomized blocks containing 60 intervarietal maize hybrids arranged in three repetitions. They were obtained through intervarietal crosses and evaluated in a diallel scheme, where 14 open-pollinated varieties were designated as parentals. Thus, 10 crosses were performed for each hybrid combination to obtain the number of seeds necessary for the competition test. The measured traits were: grain volume relative index, the mass of one hundred grains, and grain yield. The male parents and the additive genetic fraction were determinants for grain volume relative index. Mass of one hundred grains and grain yield were defined by the specific combining ability, and female parents revealed low narrow sense heritability. The female parent Taquarão and male parent Argentino Amarelo presented the best general combining abilities for the measured traits. The specific combining abilities were expressed for crosses AL 25 x Dente de Ouro Roxo, AL 25 x BRS Pampeano, and Taquarão x Argentino Branco. Genetic estimates and predictions were consistent and applicable to breeding programs and could be applied in future quantitative genetic studies of maize.

Growth hormone-releasing peptide-2 stimulates GH secretion in GH-deficient patients with mutated GH-releasing hormone receptor.

GH-releasing peptides (GHRPs) are synthetic peptides that bind to specific receptors and thereby stimulate the secretion of pituitary GH. In vivo it is uncertain whether these peptides act directly on somatotroph cells or indirectly via release of GHRH from the hypothalamus. In this study we compared the pituitary hormone response to GHRP-2 in 11 individuals with isolated GH deficiency (GHD) due to a homozygous mutation of the GHRH receptor (GHRH-R) gene and in 8 normal unrelated controls. Basal serum GH levels were lower in the GHD group compared with controls [0.11 +/- 0.11 (range, <0.04 to 0.38) vs. 0.59 +/- 0.76 microg/L (range, 0.04-2.12 microg/L); P = 0.052]. After GHRP-2 administration there was a 4.5-fold increase in serum GH relative to baseline values in the GHD group (0.49 +/- 0.41 vs. 0.11 +/- 0.11 microg/L; P = 0.002), which was significantly less than the 79-fold increase in the control group (46.8 +/- 17.6 vs. 0.59 +/- 0.76 microg/L; P = 0.008). Basal and post-GHRP-2 serum levels of ACTH, cortisol, and PRL were similar in both groups. Basal levels of serum TSH were significantly higher in the GHD group than in the control group (3.23 +/- 2.21 vs. 1.37 +/- 0.34 microIU/mL; P = 0.003). TSH levels in both groups did not change after GHRP-2 administration. These results suggest that an intact GHRH signaling system is not an absolute requirement for GHRP-2 action on GH secretion and that GHRP-2 has a GHRH-independent effect on pituitary somatotroph cells.

[Autonomic neuropathy in patients with impaired glucose tolerance]. / Neuropatia vegetativa em pacientes com tolerância diminuída a glicose.

UNLABELLED: Impaired glucose tolerance (IGT) is a clinical situation characterized by mild hyperglycemia, which is estimated to afflict 7.8% of the Brazilian population. Diabetic neuropathy is the most common complication in diabetes mellitus and it is related to morbidity and lethality in this disease. The association between IGT and peripheral neuropathy is still a matter of great concern. PURPOSE AND METHOD: In order to determine if IGT is associated with autonomic neuropathy a cross-sectional study in 44 patients with impaired glucose tolerance test (Group 1) was performed. The patients were compared to 43 control individuals (Group 2). Every patient in each group underwent anamnesis and standardized autonomic tests which consisted of heart frequency test, Valsalva maneuver, postural test and sinus arrhythmia. Routine hematologic exams as well as GTT were also made. RESULTS: Patients in group 1 had more systemic arterial hypertension, centripetal obesity, fasting and post-feeding hyperglycemia and dyslipidemia when compared with group 2. When we analysed the autonomic tests, the sinus arrhythmia test was abnormal in 54.5% of the patients in group 1 and in 32.5% in group 2 (p = 0.0039) and the Valsalva maneuver was abnormal in 34.1% of group 1 and in 7% of group 2 (p = 0.004). The postural test was not different in both groups (p = 0.334). CONCLUSION: Our results show that the involvement of the autonomic nervous system was more frequent in patients with IGT when compared to controls. These findings can explain the increased lethality due to vasculopathies observed in this group of patients and also alert physicians to care for patients with impaired glucose tolerance test.