Computed tomography-guided biopsy of mediastinal lesions: fine versus cutting needles

PURPOSE: To report the experience of a radiology department in the use of computed tomography guided biopsies of mediastinal lesions with fine and cutting needles, describing the differences between them. The results of adequacy of the sample and histologic diagnoses are presented according to the type of needle used. METHODS: We present a retrospective study of mediastinal biopsies guided by computed tomography performed from January 1993 to December 1999. Eighty-six patients underwent mediastinal biopsy in this period, 37 with cutting needles, 38 with fine needles, and 11 with both types (total of 97 biopsies). RESULTS: In most cases, it was possible to obtain an adequate sample (82.5%) and specific diagnosis (67.0%). Cutting-needle biopsy produced a higher percentage of adequate samples (89.6% versus 75.5%, P = 0.068) and of specific diagnosis (81.3% versus 53.1%, P = 0.003) than fine-needle biopsy. There were no complications that required intervention in either group. CONCLUSION: Because they are practical, safe, and can provide accurate diagnoses, image-guided biopsies should be considered the procedure of choice in the initial exploration of patients with mediastinal masses. In our experience, cutting needles gave higher quality samples and diagnostic rates. We recommend the use of cutting needles as the preferred procedure.

Effects of light and temperature on isoprene emission at different leaf developmental stages of eschweilera coriacea in central Amazon

Isoprene emission from plants accounts for about one third of annual global volatile organic compound emissions. The largest source of isoprene for the global atmosphere is the Amazon Basin. This study aimed to identify and quantify the isoprene emission and photosynthesis at different levels of light intensity and leaf temperature, in three phenological phases (young mature leaf, old mature leaf and senescent leaf) of Eschweilera coriacea (Matamatá verdadeira), the species with the widest distribution in the central Amazon. In situ photosynthesis and isoprene emission measurements showed that young mature leaf had the highest rates at all light intensities and leaf temperatures. Additionally, it was observed that isoprene emission capacity (Es) changed considerably over different leaf ages. This suggests that aging leads to a reduction of both leaf photosynthetic activity and isoprene production and emission. The algorithm of Guenther et al. (1999) provided good fits to the data when incident light was varied, however differences among E S of all leaf ages influenced on quantic yield predicted by model. When leaf temperature was varied, algorithm prediction was not satisfactory for temperature higher than ~40 °C; this could be because our data did not show isoprene temperature optimum up to 45 °C. Our results are consistent with the hypothesis of the isoprene functional role in protecting plants from high temperatures and highlight the need to include leaf phenology effects in isoprene emission models.

Detection of the viable myocardium. A perfusion scintigraphic study, before and after coronary bypass surgery in myocardial infarction patients

OBJECTIVE: To compare single-photon-emission computed tomography (SPECT) imaging scans using 201Tl and 99mTc-MIBI in detection of viable myocardium, in regions compromised by infarction. METHODS: Thirty-two (59.3±9.8 years old and 87% male) myocardial infarction patients were studied. All had Q waves on the ECG and left ventricle ejection fraction of <50%. They underwent coronary and left ventricle angiographies and SPECT before (including 201Tl reinjection) and after coronary artery bypass surgery (CABG). Improvement in perfusion observed after surgery was considered the gold standard for myocardial viability. RESULTS: Among 102 studied regions of the heart, there were 40 (39.2%) areas of transient perfusion defects in the conventional protocol with 201Tl and 52 (51.0%) after reinjection. Therefore, 12/62 (19.4%) more viable regions were identified by reinjection. Using 99mTc-MIBI, only 14 (13.7%) regions with transient defects were identified, all of which were seen also in 201Tl protocols. After surgery, 49 of a total of 93 regions analyzed (52.7%) were viable. Sensitivity, specificity, accuracy, positive and negative prediction values were, respectively, 201Tl SPECT scans - 65.3%, 90.9%, 77.4%, 88.9% and 70.2%, reinjection protocol with 201Tl scans - 81.6%, 81.8%, 81.7%, 83.3% and 80.0%; 99mTc-MIBI SPECT scans - 20.4%, 90.9%, 53.8%, 71.4% and 50.6%. Logistic regression demonstrated that the reinjection protocol with 201Tl was the best predictor of viability (P<0.001). CONCLUSION: Our data suggest the election of 201Tl for viability studies, especially when using the reinjection protocol.

Detection of coronary artery disease based on the calcification index obtained by helical computed tomography

OBJECTIVE: To assess the relation between coronary artery disease and the calcification index on helical computed tomography. METHOD: We studied 22 patients (ages ranging from 40 to 70 years) who underwent coronary angiography because of chest pain suggestive of angina pectoris. Findings on coronary angiography were classified as follows: significant obstructive disease (stenosis > or = 50%), nonobstructive disease (stenosis <50%), and no disease. With no previous knowledge of the results of the coronary angiography and within 7 days, helical computed tomography of the chest was performed. Then, data of the coronary angiography were correlated with the calcification index obtained by helical computed tomography. RESULTS: The sensitivity of helical computed tomography to the presence of significant obstructive lesions on coronary angiography was 87.5%, specificity was 100%, and negative and positive predictive values were 75% and 100%, respectively. The mean calcification index was greater in patients with severe coronary lesions, mainly when involvement of 2 or 3 vessels occurred, than that in patients with no coronary artery disease or with nonobstructive coronary artery lesions (p<0.05). CONCLUSION: Helical computed tomography is an effective method for detecting and quantifying coronary artery calcification, and it has proved to be sensitive to and specific for the noninvasive diagnosis of coronary artery stenosis.

Male Gender and Arterial Hypertension are Plaque Predictors at Coronary Computed Tomography Angiography

Background: Systemic Arterial Hypertension (SAH) is one of the main risk factors for Coronary Artery Disease (CAD), in addition to male gender. Differences in coronary artery lesions between hypertensive and normotensive individuals of both genders at the Coronary Computed Tomography Angiography (CCTA) have not been clearly determined. Objective: To Investigate the calcium score (CS), CAD extent and characteristics of coronary plaques at CCTA in men and women with and without SAH. Methods: Prospective cross-sectional study of 509 patients undergoing CCTA for CAD diagnosis and risk stratification, from November 2011 to December 2012, at Instituto de Cardiologia Dante Pazzanese. Individuals were stratified according to gender and subdivided according to the presence (HT +) or absence (HT-) of SAH. Results: HT+ women were older (62.3 ± 10.2 vs 57.8 ± 12.8, p = 0.01). As for the assessment of CAD extent, the HT+ individuals of both genders had significant CAD, although multivessel disease is more frequent in HT + men. The regression analysis for significant CAD showed that age and male gender were the determinant factors of multivessel disease and CS ≥ 100. Plaque type analysis showed that SAH was a predictive risk factor for partially calcified plaques (OR = 3.9). Conclusion: Hypertensive men had multivessel disease more often than women. Male gender was a determinant factor of significant CAD, multivessel disease, CS ≥ 100 and calcified and partially calcified plaques, whereas SAH was predictive of partially calcified plaques.

Studies on Trypanosoma rangeli Tejera 1920. IV - A reconsideration of its systematic position

The systematic positon of Trypanosoma rangeli is reconsidered and the creation of a new subgenus. Tejeraia, is proposed to remove this trypanosome from the subgenus Herptosoma of the section Stercoraria. The characteristics described for the proposed subgenus indicate that it must be located in the section Salivaria rather than in the Stercoraria. The evidence supporting this proposition is discussed in the text.

The taxonomic position of the Ctenostylidae (= Lochmostyliinae; Diptera: Schizophora)

It is shown that Ctenostylidae Bigot (1882) is a valid senior synonym of Lochmostylidae Hendel (1935). The morphology of the Ctenostylidae is considered and compared with the Pyrgotidae. It is concluded that the Ctenostylidae are not closely related to the Pyrgotidae, but form an isolated taxon of obscure relationship. Notes on a speciment of Ctenostylum sp. and a revised key to genera of Ctenostylidae are given.

Neohilgertia venusti Gen. N. SP. N. (Nematoda: Oxyuridae)from Thylamys venustus cinderellus (Thomas) Reig, Kirsch & Marshall, 1985 (Marsupialia: Didelphidae) in Burruyacu, Tucuman, Argentina - Systematic position and possible evolution

Neohilgertia gen. n. proposed for Oxyuridae nematodes from Thylamys venustus cinderellus (Marsupialia: Didelphidae) is described. The hypothesis about the possibility of a secondary parasitism for marsupials and the origin of the genus in the African Sciuridae parasite ancestors is discussed.

The type-species of Psilochlorops Duda (Diptera, Chloropidae) and its position in the phylogeny of the genus, with the description of a new species

The type-species of Psilochlorops Duda (Diptera, Chloropidae) and its position in the phylogeny of the genus, with the description of a new species. The genus Psilochlorops is known only for the Neotropical Region and had six described species to date. Psilochlorops niger sp. nov. is herein described and the male genitalia of P. clavitibia, the type-species of the genus, is described in detail. A new cladistic analysis of Psilochlorops is presented, including all known species of the genus.

The use of total luminescence spectroscopy in the investigation of the effects of different rice management practices on humic substances of a planosol

In the Earth's carbon cycle, C stocks in the soil are higher than in vegetation and atmosphere. Maintaining and conserving organic C concentrations in the soil by specific management practices can improve soil fertility and productivity. The aim of this study was to evaluate the impact of agricultural management techniques and influence of water regime (flooded or drained) on the structure of humic substances by excitation/emission matrix fluorescence. Six samples of a Planosol (Planossolo by the Brazilian System of Soil Classification) were collected from a rice field. Humic substances (HS) were extracted from flooded and drained soil under different agricultural management techniques: conventional tillage, reduced tillage and grassland. Two peaks at a long emission wavelength were observed in the EEM spectra of HA whereas those of the corresponding FA contained a unique fluorophore at an intermediate excitation/emission wavelength pair (EEWP) value. The fluorescence intensity measured by total luminescence (FI TL) of HA was lower than that of the corresponding FA. A comparison of all samples (i.e., the HA values compared to each other) revealed only slight differences in the EEWP position, but the FI TL values were significantly different. In this soil, anoxic conditions and reduced tillage (little plowing) seem to favor a higher degree of humification of the soil organic matter compared with aerated conditions and conventional tillage.