77 resultados para Measurement degree
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Purpose To evaluate the compliance and degree of satisfaction of nulligravida (has not given birth) and parous (had already given birth) women who are using intrauterine devices (IUDs). Methods A cross-sectional cohort study was conducted comparing nulligravida and parous women who had had an IUD inserted between July 2009 and November 2011. A total of 84 nulligravida women and 73 parous women were included. Interviews were conducted with women who agreed to participate through telephone contact. Statistical analysis was performed with Student s t-test and Mann-Whitney test for numeric variables; Pearson s chi-square test to test associations; and, whenever pertinent, Fisher s exact test for categorical variables. A survival curve was constructed to estimate the likelihood of each woman continuing the use of the IUD. A significance level of 5% was established. Results When compared with parous women, nulligravida women had a higher education level (median: 12 vs. 10 years). No statistically significant differences were found between the nulligravida and parous women with respect to information on the use of the IUD, prior use of other contraceptive methods, the reason for having chosen the IUD as the current contraceptive method, reasons for discontinuing the use and adverse effects, compliance, and degree of satisfaction. The two groups did not show any difference in terms of continued use of the IUD (p = 0.4). Conclusion There was no difference in compliance or the degree of satisfaction or continued use of IUDs between nulligravida and parous women, suggesting that IUD use may be recommended for women who have never been pregnant.
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High dimensional dynamical systems has intricate behavior either on temporal or on spatial evolution properties. Nevertheless, most of the work on chaotic dynamics has been concentrated on temporal behavior of low-dimensional systems. This contribution is concerned with the chaotic response of a two-degree of freedom Duffing oscillator. Since the equations of motion are associated with a five-dimensional system, the analysis is performed by considering two Duffing oscillators, both with single-degree of freedom, coupled by a spring-dashpot system. With this assumption, it is possible to analyze the transmissibility of motion between the two oscillators.
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Green sugarcane harvesting may promote great changes in the dynamics of herbicides in the environment. Our goal was to evaluate the influence of straw decomposition degree on leaching and weed (Ipomoea grandifolia) control efficacy by (14C) tebuthiuron and hexazinone. The presence of straw on the soil surface affected leaching, mainly for hexazinone (leaching reduced from 37 to 5% of the applied amount in the presence of straw). Overall, tebuthiuron showed more efficient control of Ipomoea than hexazinone. The straw decomposition degree affected only hexazinone efficacy that was lowest for the least decomposed straw. Further studies are needed to evaluate the effects of sugarcane straw on herbicides dissipation, particularly on volatilization and photolysis, to better predict their efficacy and environmental fate.
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Recent reports showing a decrease in sperm count in men have brought new concerns about male infertility. Animal models have been widely used to provide some relevant information about the human male gamete, and extrapolations are made to men and to the clinical context. The present study assesses one of the methods used for separation of germ cells of the adult rat testis, namely centrifugal elutriation followed by density gradients (Percoll®). This method was chosen since it presents the best results for cell purity in separating germ cells from the rat testis. A comparison between continuous and discontinuous Percoll® gradients was performed in order to identify the best type of gradient to separate the cells. Maximal cell purity was obtained for spermatocytes (81 ± 8.2%, mean ± SEM) and spermatids (84 ± 2.6%) using centrifugal elutriation followed by continuous Percoll® gradients. A significant difference in purity was observed between elongating spermatids harvested from continuous Percoll® gradients and from discontinuous gradients. Molecular analysis was used to assess cell contamination by employing specific probes, namely transition protein 2 (TP2), mitochondrial cytochrome C oxidase II (COX II), and sulfated glycoprotein 1 (SGP1). Molecular analysis of the samples demonstrated that morphological criteria are efficient in characterizing the main composition of the cell suspension, but are not reliable for identifying minimal contamination from other cells. Reliable cell purity data should be established using molecular analysis
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We present the results obtained with a ureterovesical implant after ipsilateral ureteral obstruction in the rat, suitable for the study of renal function after deobstruction in these animals. Thirty-seven male Wistar rats weighing 260 to 300 g were submitted to distal right ureteral ligation and divided into 3 groups, A (N = 13, 1 week of obstruction), B (N = 14, 2 weeks of obstruction) and C (N = 10, 3 weeks of obstruction). The animals were then submitted to ureterovesical implantation on the right side and nephrectomy on the left side. During the 4-week follow-up period serum levels of urea and creatinine were measured on the 2nd, 7th, 14th, 21st and 28th day and compared with preoperative levels. The ureterovesical implantation included a psoas hitch procedure and the ureter was pulled into the bladder using a transvesical suture. During the first week of the postoperative period 8 animals died, 4/13 in group A (1 week of obstruction) and 4/14 in group B (2 weeks of obstruction). When compared to preoperative serum levels, urea and creatinine showed a significant increase (P<0.05) on the 2nd postoperative day in groups A and B, with a gradual return to lower levels. However, the values in group B animals were higher than those in group A at the end of the follow-up. In group C, 2/10 animals (after 3 weeks of obstruction) were sacrificed at the time of ureterovesical implantation due to infection of the obstructed kidneys. The remaining animals in this group were operated upon but all of them died during the first week of follow-up due to renal failure. This technique of ureterovesical implantation in the rat provides effective drainage of the upper urinary tract, permitting the development of an experimental model for the study of long-term renal function after a period of ureteral obstruction
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In order to identify early abnormalities in non-insulin-dependent diabetes mellitus (NIDDM) we determined insulin (using an assay that does not cross-react with proinsulin) and proinsulin concentrations. The proinsulin/insulin ratio was used as an indicator of abnormal ß-cell function. The ratio of the first 30-min increase in insulin to glucose concentrations following the oral glucose tolerance test (OGTT; I30-0/G30-0) was taken as an indicator of insulin secretion. Insulin resistance (R) was evaluated by the homeostasis model assessment (HOMA) method. True insulin and proinsulin were measured during a 75-g OGTT in 35 individuals: 20 with normal glucose tolerance (NGT) and without diabetes among their first-degree relatives (FDR) served as controls, and 15 with NGT who were FDR of patients with NIDDM. The FDR group presented higher insulin (414 pmol/l vs 195 pmol/l; P = 0.04) and proinsulin levels (19.6 pmol/l vs 12.3 pmol/l; P = 0.03) post-glucose load than the control group. When these groups were stratified according to BMI, the obese FDR (N = 8) showed higher fasting and post-glucose insulin levels than the obese NGT (N = 9) (fasting: 64.8 pmol/l vs 7.8 pmol/l; P = 0.04, and 60 min post-glucose: 480.6 pmol/l vs 192 pmol/l; P = 0.01). Also, values for HOMA (R) were higher in the obese FDR compared to obese NGT (2.53 vs 0.30; P = 0.075). These results show that FDR of NIDDM patients have true hyperinsulinemia (which is not a consequence of cross-reactivity with proinsulin) and hyperproinsulinemia and no dysfunction of a qualitative nature in ß-cells.
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The excretion ratio of lactulose/mannitol in urine has been used to assess the extension of malabsorption and impairment of intestinal permeability. The recovery of lactulose and mannitol in urine was employed to evaluate intestinal permeability in children with and without diarrhea. Lactulose and mannitol probes were measured using high-performance liquid chromatography with pulsed amperometric detection (HPLC-PAD). Two groups of solutions containing 60 µM sugars were prepared. Group I consisted of glucosamine, mannitol, melibiose and lactulose, and group II of inositol, sorbitol, glucose and lactose. In the study of intra-experiment variation, a sample of 50 µl from each group was submitted to 4 successive determinations. The recovered amounts and retention times of each sugar showed a variation <2 and 1%, respectively. The estimated recovery was >97%. In the study of inter-experiment variation, we prepared 4 independent samples from groups I and II at the following concentrations: 1.0, 0.3, 0.1, 0.03 and 0.01 mM. The amounts of the sugars recovered varied by <10%, whereas the retention times showed an average variation <1%. The linear correlation coefficients were >99%. Retention (k'), selectivity (a) and efficiency (N) were used to assess the chromatographic conditions. All three parameters were in the normal range. Children with diarrhea presented a greater lactulose/mannitol ratio compared to children without diarrhea.
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R,S-sotalol, a ß-blocker drug with class III antiarrhythmic properties, is prescribed to patients with ventricular, atrial and supraventricular arrhythmias. A simple and sensitive method based on HPLC-fluorescence is described for the quantification of R,S-sotalol racemate in 500 µl of plasma. R,S-sotalol and its internal standard (atenolol) were eluted after 5.9 and 8.5 min, respectively, from a 4-micron C18 reverse-phase column using a mobile phase consisting of 80 mM KH2PO4, pH 4.6, and acetonitrile (95:5, v/v) at a flow rate of 0.5 ml/min with detection at lex = 235 nm and lem = 310 nm, respectively. This method, validated on the basis of R,S-sotalol measurements in spiked blank plasma, presented 20 ng/ml sensitivity, 20-10,000 ng/ml linearity, and 2.9 and 4.8% intra- and interassay precision, respectively. Plasma sotalol concentrations were determined by applying this method to investigate five high-risk patients with atrial fibrillation admitted to the Emergency Service of the Medical School Hospital, who received sotalol, 160 mg po, as loading dose. Blood samples were collected from a peripheral vein at zero, 0.5, 1.0, 1.5, 2.0, 3.0, 4.0, 6.0, 8.0, 12.0 and 24.0 h after drug administration. A two-compartment open model was applied. Data obtained, expressed as mean, were: CMAX = 1230 ng/ml, TMAX = 1.8 h, AUCT = 10645 ng h-1 ml-1, Kab = 1.23 h-1, a = 0.95 h-1, ß = 0.09 h-1, t(1/2)ß = 7.8 h, ClT/F = 3.94 ml min-1 kg-1, and Vd/F = 2.53 l/kg. A good systemic availability and a fast absorption were obtained. Drug distribution was reduced to the same extent in terms of total body clearance when patients and healthy volunteers were compared, and consequently elimination half-life remained unchanged. Thus, the method described in the present study is useful for therapeutic drug monitoring purposes, pharmacokinetic investigation and pharmacokinetic-pharmacodynamic sotalol studies in patients with tachyarrhythmias.
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Hypolactasia associated with severe iron-deficiency anemia has been reported in several studies. The objective of the present study was to determine whether hypolactasia is associated with the degree and duration of iron-deficiency anemia. Newly weaned male Wistar rats were divided into a control group receiving a diet supplemented with iron (C) and an experimental group (E) receiving a diet not supplemented with iron (iron-deficiency diet). The animals were studied on the 3rd, 5th, 7th, 14th, 21st, 28th and 35th days of the experiment, when overall and iron nutritional status and disaccharidase activity in the small intestine were determined by the Dahlqvist method. A reduction in weight occurred in the anemic animals starting on the 5th day of the study. Anemia was present in the experimental animals, with a progressive worsening up to the 14th day (hemoglobin: C = 13.27 and E = 5.37) and stabilizing thereafter. Saccharase and maltase activities did not differ significantly between groups, whereas lactase showed a significant reduction in total (TA) and specific activity (SA) in the anemic animals starting on the 21st day of the study. Median lactase TA for the C and E groups was 2.27 and 1.25 U on the 21st day, 2.87 and 1.88 U on the 28th day, and 4.20 and 1.59 U on the 35th day, respectively. Median lactase SA was 0.31 and 0.20 U/g wet weight on the 21st day, 0.39 and 0.24 U/g wet weight on the 28th day, and 0.42 and 0.23 U/g wet weight on the 35th day, respectively. These findings suggest a relationship between the enzymatic alterations observed and both the degree and duration of the anemic process. Analysis of other studies on intestinal disaccharidases in anemia suggests that the mechanism of these changes may be functional, i.e., that the enterocytes may suffer a reduction in their ability to synthesize these enzymes.
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The kallikrein-kinin system is complex, with several bioactive peptides that are formed in many different compartments. Kinin peptides are implicated in many physiological and pathological processes including the regulation of blood pressure and sodium homeostasis, inflammatory processes, and the cardioprotective effects of preconditioning. We established a methodology for the measurement of individual kinin peptides in order to study the function of the kallikrein-kinin system. The levels of kinin peptides in tissues were higher than in blood, confirming the primary tissue localization of the kallikrein-kinin system. Moreover, the separate measurement of bradykinin and kallidin peptides in man demonstrated the differential regulation of the plasma and tissue kallikrein-kinin systems, respectively. Kinin peptide levels were increased in the heart of rats with myocardial infarction, in tissues of diabetic and spontaneously hypertensive rats, and in urine of patients with interstitial cystitis, suggesting a role for kinin peptides in the pathogenesis of these conditions. By contrast, blood levels of kallidin, but not bradykinin, peptides were suppressed in patients with severe cardiac failure, suggesting that the activity of the tissue kallikrein-kinin system may be suppressed in this condition. Both angiotensin converting enzyme (ACE) and neutral endopeptidase (NEP) inhibitors increased bradykinin peptide levels. ACE and NEP inhibitors had different effects on kinin peptide levels in blood, urine, and tissues, which may be accounted for by the differential contributions of ACE and NEP to kinin peptide metabolism in the multiple compartments in which kinin peptide generation occurs. Measurement of the levels of individual kinin peptides has given important information about the operation of the kallikrein-kinin system and its role in physiology and disease states.
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Our aim was to observe the induction of panic attacks by a hyperventilation challenge test in panic disorder patients (DSM-IV) and their healthy first-degree relatives. We randomly selected 25 panic disorder patients, 31 healthy first-degree relatives of probands with panic disorder and 26 normal volunteers with no family history of panic disorder. All patients had no psychotropic drugs for at least one week. They were induced to hyperventilate (30 breaths/min) for 4 min and anxiety scales were applied before and after the test. A total of 44.0% (N = 11) panic disorder patients, 16.1% (N = 5) of first-degree relatives and 11.5% (N = 3) of control subjects had a panic attack after hyperventilating (chi² = 8.93, d.f. = 2, P = 0.011). In this challenge test the panic disorder patients were more sensitive to hyperventilation than first-degree relatives and normal volunteers. Although the hyperventilation test has a low sensitivity, our data suggest that there is no association between a family history of panic disorder and hyperreactivity to an acute hyperventilation challenge test. Perhaps cognitive variables should be considered to play a specific role in this association since symptoms of a panic attack and acute hyperventilation overlap.
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Ultrasonic attenuation coefficient, wave propagation speed and integrated backscatter coefficient (IBC) of human coronary arteries were measured in vitro over the -6 dB frequency bandwidth (36 to 67 MHz) of a focused ultrasound transducer (50 MHz, focal distance 5.7 mm, f/number 1.7). Corrections were made for diffraction effects. Normal and diseased coronary artery sub-samples (N = 38) were obtained from 10 individuals at autopsy. The measured mean ± SD of the wave speed (average over the entire vessel wall thickness) was 1581.04 ± 53.88 m/s. At 50 MHz, the average attenuation coefficient was 4.99 ± 1.33 dB/mm with a frequency dependence term of 1.55 ± 0.18 determined over the 36- to 67-MHz frequency range. The IBC values were: 17.42 ± 13.02 (sr.m)-1 for thickened intima, 11.35 ± 6.54 (sr.m)-1 for fibrotic intima, 39.93 ± 50.95 (sr.m)-1 for plaque, 4.26 ± 2.34 (sr.m)-1 for foam cells, 5.12 ± 5.85 (sr.m)-1 for media and 21.26 ± 31.77 (sr.m)-1 for adventitia layers. The IBC results indicate the possibility for ultrasound characterization of human coronary artery wall tissue layer, including the situations of diseased arteries with the presence of thickened intima, fibrotic intima and plaque. The mean IBC normalized with respect to the mean IBC of the media layer seems promising for use as a parameter to differentiate a plaque or a thickened intima from a fibrotic intima.
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To identify early metabolic abnormalities in type 2 diabetes mellitus, we measured insulin secretion, sensitivity to insulin, and hepatic insulin extraction in 48 healthy normal glucose-tolerant Brazilians, first-degree relatives of type 2 diabetic patients (FH+). Each individual was matched for sex, age, weight, and body fat distribution with a person without history of type 2 diabetes (FH-). Both groups were submitted to a hyperglycemic clamp procedure (180 mg/dl). Insulin release was evaluated in its two phases. The first was calculated as the sum of plasma insulin at 2.5, 5.0, 7.5, and 10.0 min after the beginning of glucose infusion, and the second as the mean plasma insulin level in the third hour of the clamp procedure. Insulin sensitivity index (ISI) was the mean glucose infusion rate in the third hour of the clamp experiment divided by the mean plasma insulin concentration during the same period of time. Hepatic insulin extraction was determined under fasting conditions and in the third hour of the clamp procedure as the ratio between C-peptide and plasma insulin levels. FH+ individuals did not differ from FH- individuals in terms of the following parameters [median (range)]: a) first-phase insulin secretion, 174 (116-221) vs 207 (108-277) µU/ml, b) second-phase insulin secretion, 64 (41-86) vs 53 (37-83) µU/ml, and c) ISI, 14.8 (9.0-20.8) vs 16.8 (9.0-27.0) mg kg-1 min-1/µU ml-1. Hepatic insulin extraction in FH+ subjects was similar to that of FH- ones at basal conditions (median, 0.27 vs 0.27 ng/µU) and during glucose infusion (0.15 vs 0.15 ng/µU). Normal glucose-tolerant Brazilian FH+ individuals well-matched with FH- ones did not show defects of insulin secretion, insulin sensitivity, or hepatic insulin extraction as tested by hyperglycemic clamp procedures.
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The aim of the present study was to measure full epidermal thickness, stratum corneum thickness, rete length, dermal papilla widening and suprapapillary epidermal thickness in psoriasis patients using a light microscope and computer-supported image analysis. The data obtained were analyzed in terms of patient age, type of psoriasis, total body surface area involvement, scalp and nail involvement, duration of psoriasis, and family history of the disease. The study was conducted on 64 patients and 57 controls whose skin biopsies were examined by light microscopy. The acquired microscopic images were transferred to a computer and measurements were made using image analysis. The skin biopsies, taken from different body areas, were examined for different parameters such as epidermal, corneal and suprapapillary epidermal thickness. The most prominent increase in thickness was detected in the palmar region. Corneal thickness was more pronounced in patients with scalp involvement than in patients without scalp involvement (t = -2.651, P = 0.008). The most prominent increase in rete length was observed in the knees (median: 491 µm, t = 10.117, P = 0.000). The difference in rete length between patients with a positive and a negative family history was significant (t = -3.334, P = 0.03), being 27% greater in psoriasis patients without a family history. The differences in dermal papilla distances among patients were very small. We conclude that microscope-supported thickness measurements provide objective results.
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Pituitary adenomas sometimes show rapid growth and recurrence, and about one third invade the structures surrounding the sella turcica. In an attempt to determine aggressive behavior at an early stage, we used the MIB-1 antibody to identify the Ki-67 antigen. The present study was designed to evaluate pituitary adenomatous tissue in terms of secretion and proliferation and to correlate the Ki-67 index with hormone phenotype and invasive behavior. Material from 159 patients submitted to one or more resections of pituitary adenomas was evaluated. Forty-two non-secretory adenomas and 43 adenomas immunoreactive for growth hormone, 19 for prolactin, 18 for growth hormone and prolactin, 16 for adrenocorticotropic hormone (ACTH), and 21 cases of plurihormonal/gonadotropin adenomas were detected by immunohistochemistry. The MIB-1 antibody was positive in 139 samples and the Ki-67 index ranged from 0.16 to 15.48% (mean = 1.22 ± 2.09%), with no significant difference between genders, age groups, or secretory and non-secretory status. The Ki-67 index was higher in ACTH-secreting adenomas. Invasive pituitary adenomas had a significantly higher Ki-67 index (2.01 ± 3.15%) than macroadenomas with or without supra-sellar extension (1.12 ± 1.87%; P = 0.02). The index was not significantly different in the subgroup of adenomas with invasion of the cavernous sinus compared to groups with other types of invasion. We conclude that tumoral proliferative activity evaluated by the detection of the Ki-67 antigen is significantly higher in invasive than noninvasive adenomas, information which can be useful in therapeutic postoperative management since index cut-off values associated with aggressive behavior can be established.