Molecular, anatomical and physiological properties of a genetically modified soybean line transformed with rd29A:AtDREB1A for the improvement of drought tolerance.

We evaluated the molecular, anatomical and physiological properties of a soybean line transformed to improve drought tolerance with an rd29A:AtDREB1A construct. This construct expressed dehydration- responsive element binding protein DREB1A from the stress-inducible rd29A promoter. The greenhouse growth test included four randomized blocks of soybean plants, with each treatment performed in triplicate. Seeds from the non-transformed soybean cultivar BR16 and from the genetically modified soybean P58 line (T(2) generation) were grown at 15% gravimetric humidity for 31 days. To induce water deficit, the humidity was reduced to 5% gravimetric humidity (moderate stress) for 29 days and then to 2.5% gravimetric humidity (severe stress). AtDREB1A gene expression was higher in the genetically modified P58 plants during water deficit, demonstrating transgene stability in T(2) generations and induction of the rd29A promoter. Drought-response genes, including GmPI-PLC, GmSTP, GmGRP, and GmLEA14, were highly expressed in plants submitted to severe stress. Genetically modified plants had higher stomatal conductance and consequently higher photosynthetic and transpiration rates. In addition, they had more chlorophyll. Overexpression of AtDREB1A may contribute to a decrease in leaf thickness; however, a thicker abaxial epidermis was observed. Overexpression of AtDREB1A in soybean appears to enhance drought tolerance.

Transcription factors expressed in soybean roots under drought stress.

To gain insight into stress-responsive gene regulation in soybean plants, we identified consensus sequences that could categorize the transcription factors MYBJ7, BZIP50, C2H2, and NAC2 as members of the gene families myb, bzip, c2h2, and nac, respectively. We also investigated the evolutionary relationship of these transcription factors and analyzed their expression levels under drought stress. The NCBI software was used to find the predicted amino acid sequences of the transcription factors, and the Clustal X software was used to align soybean and other plant species sequences. Phylogenetic trees were built using the Mega 4.1 software by neighbor joining and the degree of confidence test by Bootstrap. Expression level studies were carried out using hydroponic culture; the experiments were designed in completely randomized blocks with three repetitions. The blocks consisted of two genotypes, MG/BR46 Conquista (drought-tolerant) and BR16 (drought-sensitive) and the treatments consisted of increasingly long dehydration periods (0, 25, 50, 75, and 100 min). The transcription factors presented domains and/or conserved regions that characterized them as belonging to the bzip, c2h2, myb, and nac families. Based on the phylogenetic trees, it was found that the myb, bzip and nac genes are closely related to myb78, bzip48 and nac2 of soybean and that c2h2 is closely related to c2h2 of Brassica napus. Expression of all genes was in general increased under drought stress in both genotypes. Major differences between genotypes were due to the lowering of the expression of the mybj7 and c2h2 genes in the drought-tolerant variety at some times. Over-expression or silencing of some of these genes has the potential to increase stress tolerance.

Estabilidade articular mecânica e funcional / Mechanic and functional joint stability

A estabilidade articular é um requisito essencial para que um indivíduo realize atividades funcionais e é descrita na literatura por dois tipos de estabilidade, a mecânica e a funcional. Tem-se discutido sobre a relação direta entre os dois tipos de estabilidade, entretanto a falta de correlação entre elas tem sido demonstrada. O objetivo deste estudo foi analisar os fatores que contribuem para a estabilidade mecânica e a estabilidade funcional e discutir arelação entre elas. A estabilidade mecânica é determinada pela geometria articular e pelas propriedades mecânicas dos tecidos que se encontram dentro e ao redor da articulação. Entretanto vários estudos apresentam evidências de que durante a realização de diversas atividades funcionais a rigidez passiva das articulações parece não ser suficientes para garantir sua estabilidade. Estabilidade articular funcional é a condição que permite um desempenho normal de uma articulação durante uma atividade funcional. É promovida pelos fatores contribuintes para a estabilidade mecânica somado a resultante de força que age sobre uma articulação. Durantemuito tempo, e mesmo atualmente, tem-se assumido que testes clínicos de frouxidão positivos são indicativos de instabilidade e conseqüentemente de incapacidade. Entretanto, a maioria dosestudos que avaliou desempenho funcional e frouxidão não encontrou correlação entre estas duas variáveis. Apesar dos testes de frouxidão serem úteis no diagnóstico de uma lesão ligamentar, a sua utilidade na predição do desfecho funcional do indivíduo após a lesão é limitada.

Joint stability is an essential requirement to subject practice functional activities. It is described at literature by two types of stability, the mechanical and the functional. A lot has been discussing about the direct relationship between the two types of stability, however a lack of correlation among them has been demonstrated. The purpose of this study was to analyze the factors that contribute to the mechanical stability and the functional stability of a joint and to discuss the relationship between them. The mechanic stability is determined by the joint geometry and mechanicals properties of the tissues within and around the joint. However, many studies have shown evidences that during the practice of several functional activities the joint passive stiffness is not sufficient to guarantee joint stability. Functional joint stability is the condition of a joint that allows normal performance of the individual during physical activities. It is determined by the factors that contribute to mechanic stability and by resulting forces that act on the joint. For a long time, and even nowadays, it has been assumed that positive clinical laxity test were indicative of instability and consequently of impairment. However, most of the studies that evaluated functional performance and laxity didn’t find association between thesetwo variables. In spite of the usefulness of the tests of laxity in the diagnosis of ligamentar lesion, their capacity of predicting individual’s functional outcome after the lesion is limited.

The pathophysiological basis for intensive insulin replacement.

Both type I and type II diabetes are characterised by a progressive decrease in beta-cell function and mass. In type I diabetes, autoimmune destruction results in rapid loss of beta-cell function, and insulin therapy is essential to maintain normoglycaemia. In type II diabetes, a diminished or absent first-phase insulin release is the earliest metabolic defect, which is accompanied by lack of prandial suppression of hepatic glucose production, increased postprandial glucose excursions and late insulin hypersecretion. Furthermore, chronic exposure to elevated glucose, even to intermittent postprandial spikes, results in further deterioration of the beta-cell function ('glucotoxicity'). By the time type II diabetes is diagnosed, beta-cell function and mass have declined by about 50%. With the progression of the disease and glucotoxicity there is continuous decrease in beta-cell mass due to increased apoptosis that results in absolute insulin deficiency. By then, patients require insulin administration to maintain glucose control. An increasing body of evidence demonstrates the importance of preserving endogenous beta-cell function both in type I and type II diabetes. Early and intensive glycaemic control, using regimens which re-create a physiological insulin profile, controlling postprandial as well as fasting glucose levels, offers the most promise for preserving beta-cell function, decreasing disease progression, and reducing the chronic complications of diabetes.

Endocrine causes of bone disease.

Hyperthyroidism, glucocorticoid excess, hyperparathyroidism, hypogonadism, and acromegaly decrease bone mineral density and aggravate the osteoporotic tendencies of elderly individuals. After effective treatment of endocrinopathy, the bone attempts to return to the normal mineral density. In most circumstances, however, this attempt is incomplete. Early diagnosis and treatment of these endocrine problems in older patients helps to maintain their skeletal integrity and prevent osteoporotic fractures.

Thyroid nodules in the elderly.

Thyroid nodules in the elderly are more frequent and more frequently malignant. Fine needle aspiration is the first step to diagnose these type of nodules, and thyroid scans and ultrasounds may be obtained in special cases. Thyroid suppression is frequently not effective in decreasing the size of the nodule and may cause subclinical or clinical thyrotoxicosis. It is not uncommon to discover that what initially was thought to be a solitary nodule is only the dominant nodule of a multinodular goiter.

Erosive spondyloarthropathy in primary hyperparathyroidism without renal failure.

A patient with erosive spondyloarthropathy (ESA) and primary hyperparathyroidism is described. In the past, ESA has been described exclusively in patients with chronic renal failure (CRF) and has been attributed to crystal deposition, amyloidosis, severe secondary hyperparathyroidism, or other abnormalities of chronic renal failure. This patient with normal renal function suggests that secondary hyperparathyroidism plays the major pathogenetic role in ESA in patients with renal failure.

Felodipine (once daily) versus nifedipine (four times daily) for Prinzmetal's angina pectoris.

In 30 consecutive patients with Prinzmetal's angina pectoris, the antiischemic effect of felodipine, a new long-acting vasoselective calcium antagonist, administered at doses of 10 and 20 mg once daily was compared with that of the well-established therapeutic regimen with nifedipine administered at a dose of 20 mg 4 times daily. Twenty-four-hour Holter monitoring was performed during a 2-day placebo run-in and at the end of each of 3 consecutive 6-day periods during which the 3 active treatments were administered in randomized sequence. Three patients withdrew, whereas 27 completed the study. The therapeutic regimens tested proved to be similarly effective; primary end points (ischemic episodes recorded by Holter monitoring, and anginal attacks reported on diary cards) occurred in 5 patients (19%) during nifedipine treatment, and in 7 (26%) and 3 (11%) during felodipine treatment with 10 and 20 mg, respectively (p = not significant). The distribution of residual ischemic episodes demonstrated that treatment with felodipine once daily provides 24-hour antiischemic protection. Twenty-six patients were followed up with 20 mg of felodipine once daily for a mean of 6 +/- 5 months, and 21 of them (81%) remained free of symptoms and Holter-recorded ischemic attacks. It is concluded that for Prinzmetal's angina pectoris, 24-hour antiischemic protection may be achieved with administration of felodipine once daily. The availability of a simplified therapeutic approach may constitute a real advantage in terms of patient compliance and improving the quality of life.

Fibrinopeptide A excretion in urine: a marker of the cumulative thrombin activity in stable versus unstable angina patients.

Plasma levels and 24-hour urine excretion of fibrinopeptide A were measured in a consecutive series of 179 patients with angina pectoris. Sixty-four patients had stable angina and 115 patients had unstable angina. Urine was collected over 24 hours the day before coronary arteriography, and blood samples were taken at the end of urine collection. When the values of fibrinopeptide A in plasma and in the 24-hour urine specimens were compared, no significant correlation was found in patients with either stable (rs = 0.16, difference not significant) and unstable (rs = 0.07, difference not significant) angina. The concentrations of fibrinopeptide A in the plasma did not differ significantly when patients with stable angina (range 0.1 to 82.6, median 7.4 ng/mL) were compared with patients with unstable angina (range 0.2 to 61.7, median 14 ng/mL, p = 0.055), whereas fibrinopeptide A 24-hour urinary excretion was significantly higher in patients with unstable angina (range 0.3 to 38.1, median 11.8 micrograms/24 hr) than in patients with stable angina (range 0.4 to 38.1, median 3.8 micrograms/24 hr, p less than 0.001). Twenty-four-hour urine excretion of fibrinopeptide A in patients with unstable angina and angiographically documented intracoronary thrombi were higher than the corresponding values in patients with unstable angina without such angiographic characteristic (p less than 0.001). The largest increase in plasma and urine concentration of fibrinopeptide A was observed in patients whose first episode of angina at rest occurred within the previous 48 hours. We conclude that the cumulative thrombin activity, assessed by 24-hour urinary excretion of fibrinopeptide A, is a more useful index, compared with single fibrinopeptide A measurement in plasma, for discriminating between patients with stable and with unstable angina pectoris.

Ability of calcium-entry blockade by felodipine to disclose different pathogenetic mechanisms behind hyperventilation-induced myocardial ischemia in men.

To verify that myocardial ischemia occurring during either the overbreathing or recovery phase of the hyperventilation test is based on different pathogenetic mechanisms, 2 consecutive series of patients, selected on the basis of their response to a run-in hyperventilation test, were studied. Group I comprised 15 patients who developed ST-segment depression early during overbreathing, whereas group II consisted of 12 patients showing ST-segment depression late during the recovery phase. A single oral dose of felodipine 10 mg or of placebo was administered on 2 consecutive days according to a randomized, double-blind, crossover design, and the hyperventilation test was repeated, on both days of the study, 3 to 5 hours after drug intake. In group I, ST-segment depression occurred after placebo in all patients during overbreathing, with an increase in rate pressure product (from 112 +/- 31 at baseline to 168 +/- 55 mm Hg x beats/min/100 at the onset of ST-segment depression; p less than 0.01). After felodipine, 13 patients continued to show ST-segment depression during overbreathing, together with an increase in rate pressure product (from 107 +/- 24 at baseline to 158 +/- 46 mm Hg x beats/min/100 at the onset of electrocardiographic changes; p less than 0.01). In group II, all 12 patients showed ST-segment depression during recovery after placebo, with a rate pressure product comparable to baseline conditions (112 +/- 35 at baseline vs 102 +/- 27 mm Hg x beats/min/100 at the onset of ST-segment depression; difference not significant). After felodipine, no patient developed ST-segment depression or chest pain.(ABSTRACT TRUNCATED AT 250 WORDS)

Recombinant tissue-type plasminogen activator followed by heparin compared with heparin alone for refractory unstable angina pectoris.

Patients with unstable angina pectoris who remain symptomatic despite medical treatment are at high risk of death and myocardial infarction. The incidence of refractory unstable angina was examined in a consecutive series of 103 patients who received conventional medical treatment with nitrates, beta blockers, calcium antagonists and aspirin. During 48 hours of continuous electrocardiographic monitoring, 24 patients had greater than or equal to 1 anginal attack, 5 of whom had both painful and painless ischemic episodes. In these 24 patients with unstable angina refractory to conventional medical treatment, the short-term efficacy of recombinant tissue-type plasminogen activator (rt-PA) followed by heparin was assessed and compared with heparin alone in a randomized double-blind trial. Recurrences of ischemic attacks during a 72-hour follow-up period were documented in 9 of the 12 patients given heparin alone. All patients experienced at least 1 symptomatic ischemic episode and 1 patient had both painful and painless ischemia. No patient given rt-PA plus heparin had either symptomatic or asymptomatic ischemic attacks during follow-up. Kaplan-Meier curves analysis demonstrated a significantly higher probability of being ischemia free in the group of patients treated with rt-PA followed by heparin than in the group treated with heparin alone (p less than 0.01). Quantitative coronary arteriography failed to reveal any significant changes of ischemia-related lesions before and after each treatment. This study demonstrates that the combination of rt-PA and heparin has a greater protective effect than heparin alone in treating recurrent ischemic episodes in patients with refractory unstable angina.(ABSTRACT TRUNCATED AT 250 WORDS)

Usefulness of the hyperventilation test in stable exertional angina pectoris in selecting medical therapy.

To assess the prevalence of abnormal coronary vasoconstriction in stable exertional angina and to evaluate whether the presence of increased coronary tone may have therapeutic implications, we studied 83 consecutive patients with typical exertional angina, positive response to exercise stress testing and documented coronary artery disease. Abnormal coronary vasoconstriction was induced by a hyperventilation test in 16 patients (group I) while the remaining 67 had a negative response (group II). No differences were observed between the 2 groups with regard to clinical, exercise and angiographic data. All group I patients and 16 patients in group II repeated hyperventilation and exercise tests after the administration of dihydropyridine-type calcium antagonists (7 patients nifedipine, 9 patients felodipine). After treatment 15 of 16 group I patients had a negative response to the hyperventilation test. The total exercise duration was significantly increased (278 +/- 183 vs 554 +/- 248 seconds; p less than 0.001) with higher values of rate pressure product at peak exercise (168 +/- 47 vs 235 +/- 67 mm Hg x beats/min/100; p less than 0.0025). In group II no significant differences were observed between pre- and posttreatment values for total exercise duration (244 +/- 210 vs 308 +/- 243 seconds) and rate pressure product at peak exercise (170 +/- 46 vs 188 +/- 56 mm Hg x beats/min/100). These data show that the hyperventilation test can be used to select a subset of patients with stable exertional angina and detectable abnormal coronary vasoconstriction who will improve their exercise tolerance with coronary vasodilator treatment.

Altering the progression of human alveolar bone loss with the non-steroidal anti-inflammatory drug flurbiprofen.

The treatment of human periodontal diseases relies on mechanical and antimicrobial suppression of the etiologic bacteria. The ability to alter the progression of periodontitis by additionally blocking host pathways involved in the destructive process is an area of current research. Prostaglandins and other metabolites of arachidonic acid are believed to be important host mediators of the bone resorption of diseases such as periodontitis. We have previously examined the effect of inhibitors of prostaglandin production, non-steroidal anti-inflammatory drugs (NSAIDs), on inhibiting alveolar bone loss in beagles. The present study was designed to examine the effect of the NSAID, flurbiprofen, on slowing the radiographic loss of alveolar bone in the human. Fifty-six individuals with radiographic evidence of alveolar bone loss were recruited for study. Forty-four patients remained in the study for the data analysis of loss of alveolar bone. Following a 6 month baseline pretreatment period to measure the radiographic progression of bone loss, half of the patients were administered flurbiprofen, 50 mg. b.i.d., while half were administered a placebo. All patients received a subgingival scaling and pumice by a hygienist every 6 months. The rate of alveolar bone loss in a 2 year treatment period was compared to the baseline 6 month pretreatment period within and between patient groups. Throughout the study, teeth exhibiting obvious loss of bone were exited from study and treated with conventional mechanical therapy. At the end of the pretreatment period both patient groups had a similar mean rate of alveolar bone loss.(ABSTRACT TRUNCATED AT 250 WORDS)

Spontaneous hematoma of a parathyroid adenoma.

A patient with long-standing, asymptomatic, primary hyperparathyroidism developed pain in the anterior neck area, with cough, dysphagia and increasing shortness of breath. This led to respiratory insufficiency, which required endotracheal intubation and respirator assistance. During the ensuing hours the patient developed an area of ecchymosis on the anterior chest. Chest x-ray showed widening of the superior mediastinum, and CT scan showed a large mass with a fluid level. Surgery revealed a large hematoma originating from a mediastinal parathyroid adenoma with a hemorrhagic infarct. Serum calcium, previously elevated, decreased to normal with the onset of neck pain, and the patient remains normocalcemic. Previous reported cases of this rare complication of parathyroid adenomas are reviewed. Hemorrhagic infarct of a parathyroid adenoma may present with a rapidly enlarging mediastinal mass, and/or hypercalcemic crisis. Surgical removal of the infarcted adenoma can return the serum calcium to normal.

¿Han quedado obsoletos los análisis de glucosuria? / Is the urine glucose test obsolete

El control metabólico de la diabetes mellitus realizado por los pacientes se ha llevado a cabo durante muchos años con exámenes de orina. La necesidad de un estricto control, en voga durante los últimos años, pone énfasis en el monitoreo del azúcar sanguíneo en el hogar. Se desea evaluar el estaod y la tecnología de los exámenes de glucosuria en la actualidad, a fin de observar cuál debe ser su papel en el trtamiento diario. El manejo renal de la glucosa depende de la concentración de azúcar, el índice de filtración glomerular y la reabsorción tubular. La mayor parte de los 180 g de glucosa filtrados diariamente en los glomérulos se reabsorbe en los túbulos por un proceso activo. Los métodos actuales utilizados por los pacientes diabéticos para medir el azúcar en la orina en los EEUU son: tabletas Clinitest, Testape, Diastix y Chemstrip uG. Se revisa cada uno de ellos, señalando sus beneficios e inconvenientes, así como sus falsas reacciones piositivos y negativas. Debido a su simplicidad y rango más amplio, parece ser que Chemstrip uG es el mejor en la actualidad, aunque también es uno de los más caros. La recolección de orina para estas determinaciones pueden ser cuantitativa o semicuantitativa. En la práctica diaria los exámenes de glucosuria tienen algunos problemas serios: variaciones en el umbral renal de paciente a paciente y en el mismo paciente, disociación temporal entre el azúcar de sangre y el la orina, variaciones con el estado de hidratación, falsas reacciones positivas y negativas, requiriendo además del paciente esfuerzo, técnicas cuidadosas y gastos

Granuloma-related hypercalcemia in lipoid pneumonia.

A patient with hypercalcemia, suppressed serum PTH levels, and elevated serum levels of calcitriol was found to have a granulomatous lipoid pneumonia due to chronic aspiration of a "vaporizing ointment." After the surgical removal of the largest granuloma, the serum calcium and calcitriol levels rapidly returned to normal. This is a new instance of granuloma-induced hypercalcemia, probably mediated by the activation of vitamin D by cells of the granulomatous reaction.

Untreated thyrotoxicosis as a manifestation of anorexia nervosa.

A patient with anorexia nervosa refused treatment for her thyrotoxicosis for 18 years in an attempt to keep her weight low. Severe congestive heart failure and impending thyroid storm prompted her family to force her to seek medical attention.