Hyaluronidase shortens levobupivacaine lumbosacral epidural anaesthesia in dogs

Methods: Six adult mixed breed dogs (two males and four females) weighing 7 to 14 kg (10 center dot 5 +/- 1 center dot 5 kg) and aged two to five years were used. Each dog received both treatments in random order: levobupivacaine alone (LBA; n=6) or levobupivacaine plus hyaluronidase (LBH; n=6) administered in the lumbosacral epidural space. Systemic effects, spread and duration of anaesthesia and motor block were determined before treatment and at predetermined intervals. Results: The duration of local anaesthesia was 90 +/- 10 minutes (P=0 center dot 001) for LBH treatment and 150 +/- 15 minutes for LBA treatment. In the LBH treatment, anaesthesia reached the T12 to T13 dermatome and in the LBA treatment it reached the T11 to T12 dermatome in all animals in 5 and 15 minutes, respectively. Complete motor blockade was 75 +/- 12 minutes (P=0 center dot 01) and 120 +/- 15 minutes for LBH and LBA treatments, respectively. Clinical Significance: Hyaluronidase added to levobupivacaine significantly shortens the duration of epidural anaesthesia with the same dermatome spread into the epidural space in dogs.

Experimental Model of Isolated Lung Perfusion in Rats: First Brazilian Experience Using the IL-2 Isolated Perfused Rat or Guinea Pig Lung System

Introduction. Lung transplantation has become the mainstay therapy for patients with end-stage lung disease refractory to medical management. However, the number of patients listed for lung transplantation largely exceeds available donors. The study of lung preservation requires accurate, cost-effective small animal models. We have described a model of ex vivo rat lung perfusion using a commercially available system. Methods. Male Wistar rats weighing 250 g-300 g were anesthetized with intraperitoneal sodium thiopental (50 mg/kg body weight). The surgical technique included heart-lung block extraction, assembly, and preparation for perfusion and data collection. We used an IL-2 Isolated Perfused Rat or Guinea Pig Lung System (Harvard Apparatus, Holliston, Mass, United States; Hugo Sachs Elektronik, Alemanha). Results. Preliminary results included hemodynamic and pulmonary mechanics data gathered in the experiments. Conclusion. The isolated rat lung perfusion system is a reliable method to assess lung preservation.

Hyperkalemia: A quick reference

This article serves as a quick reference for hyperkalemia. Guidelines for analysis and causes, signs, and a stepwise approach are presented.

Hypokalemia: A quick reference

This article serves as a quick reference for hypokalemia. Guidelines for analysis and causes, signs, and a stepwise approach are presented.

Denisiuk-type reflection holography display with sillenite crystals for imaging and interferometry of small objects

A novel setup for imaging and interferometry through reflection holography with Bi12TiPO20(BTO) sillenite photorefractive crystals is proposed. A variation of the lensless Denisiuk arrangement was developed resulting in a compact, robust and simple interferometer. A red He-Ne laser was used as light source and the holographic recording occurred by diffusion with the grating vector parallel to the crystal [0 0 1]-axis. In order to enhance the holographic image quality and reduce noise a polarizing beam splitter (PBS) was positioned at the BTO input and the crystal was tilted around the [0 0 1]-axis. This enabled the orthogonally polarized transmission and diffracted beams to be separated by the PBS, providing the holographic image only. The possibility of performing deformation and strain analysis as well as vibration measurement of small objects was demonstrated. (C) 2007 Elsevier B.V. All rights reserved.

Synchrotron X-ray imaging via ultra-small-angle scattering: principles of quantitative analysis and application in studying bone integration to synthetic grafting materials

Optimized experimental conditions for extracting accurate information at subpixel length scales from analyzer-based X-ray imaging were obtained and applied to investigate bone regeneration by means of synthetic beta-TCP grafting materials in a rat calvaria model. The results showed a 30% growth in the particulate size due to bone ongrowth/ingrowth within the critical size defect over a 1-month healing period.

Fluorescence spectroscopy for the detection of tongue carcinoma - validation in an animal model

The efficacy of fluorescence spectroscopy to detect squamous cell carcinoma is evaluated in an animal model following laser excitation at 442 and 532 nm. Lesions are chemically induced with a topical DMBA application at the left lateral tongue of Golden Syrian hamsters. The animals are investigated every 2 weeks after the 4th week of induction until a total of 26 weeks. The right lateral tongue of each animal is considered as a control site (normal contralateral tissue) and the induced lesions are analyzed as a set of points covering the entire clinically detectable area. Based on fluorescence spectral differences, four indices are determined to discriminate normal and carcinoma tissues, based on intraspectral analysis. The spectral data are also analyzed using a multivariate data analysis and the results are compared with histology as the diagnostic gold standard. The best result achieved is for blue excitation using the KNN (K-nearest neighbor, a interspectral analysis) algorithm with a sensitivity of 95.7% and a specificity of 91.6%. These high indices indicate that fluorescence spectroscopy may constitute a fast noninvasive auxiliary tool for diagnostic of cancer within the oral cavity. (C) 2008 Society of Photo-Optical Instrumentation Engineers.

Quorum sensing detected by atomic force microscopy imaging of corrals surrounding multicellular arrangement of bacteria

Connectivity of the glycocalyx covering of small communities of Acidithiobacillus ferrooxidans bacteria deposited on hydrophilic mica plates was imaged by atomic force microscopy. When part of the coverage was removed by water rinsing, an insoluble structure formed by corrals surrounding each individual bacterium was observed. A collective ring structure with clustered bacteria (>= 3) was observed, which indicates that the bacteria perceived the neighborhood in order to grow a protective structure that results in smaller production of exopolysaccharides material. The most surprising aspect of these collective corral structures was that they occur at a low bacterial cell density. The deposited layers were also analyzed by confocal Raman microscopy and shown to contain polysaccharides, protein, and glucoronic acid.

Imaging and lung cancer

Lung cancer remains the most common cause of cancer-related mortality in Scotland, accounting for 28.9% of all cancer deaths in 2007. Current guidelines recommend assessment of patient fitness and operability by a multidisciplinary team when selecting management options. Two of the most important prognostic markers are the stage of disease and ECOG performance status. In 1996, the International Association for the Study of Lung Cancer (IASLC) launched a worldwide TNM staging project to create international databases that would be used to continue the excellent efforts of Dr. Cliff Mountain, who pioneered this approach to lung cancer staging in 1973. Successive iterations of tumor, nodule, metastasis (TNM) staging for lung cancer have addressed shortcomings identified by the oncology community. Similarly, the IASLC recognized that it is important that further revisions continue to be made to ensure that the international staging system for lung cancer remains fit for its purpose. The last work of the International Staging Committee (ISC) was the conduct of the study that informed the seventh edition of the international staging system for lung cancer, in 2010. This review of image and staging in non small cell lung cancer (NSCLC), includes a summary of the different noninvasive tests currently available for staging non small cell lung cancer.

Real-time detection of pneumothorax using electrical impedance tomogyaphy

Objectives: Pneumothorax is a frequent complication during mechanical ventilation. Electrical impedance tomography (EIT) is a noninvasive tool that allows real-time imaging of regional ventilation. The purpose of this study was to 1) identify characteristic changes in the EIT signals associated with pneumothoraces; 2) develop and fine-tune an algorithm for their automatic detection; and 3) prospectively evaluate this algorithm for its sensitivity and specificity in detecting pneumothoraces in real time. Design: Prospective controlled laboratory animal investigation. Setting: Experimental Pulmonology Laboratory of the University of Sao Paulo. Subjects: Thirty-nine anesthetized mechanically ventilated supine pigs (31.0 +/- 3.2 kg, mean +/- SD). Interventions. In a first group of 18 animals monitored by EIT, we either injected progressive amounts of air (from 20 to 500 mL) through chest tubes or applied large positive end-expiratory pressure (PEEP) increments to simulate extreme lung overdistension. This first data set was used to calibrate an EIT-based pneumothorax detection algorithm. Subsequently, we evaluated the real-time performance of the detection algorithm in 21 additional animals (with normal or preinjured lungs), submitted to multiple ventilatory interventions or traumatic punctures of the lung. Measurements and Main Results: Primary EIT relative images were acquired online (50 images/sec) and processed according to a few imaging-analysis routines running automatically and in parallel. Pneumothoraces as small as 20 mL could be detected with a sensitivity of 100% and specificity 95% and could be easily distinguished from parenchymal overdistension induced by PEEP or recruiting maneuvers, Their location was correctly identified in all cases, with a total delay of only three respiratory cycles. Conclusions. We created an EIT-based algorithm capable of detecting early signs of pneumothoraces in high-risk situations, which also identifies its location. It requires that the pneumothorax occurs or enlarges at least minimally during the monitoring period. Such detection was operator-free and in quasi real-time, opening opportunities for improving patient safety during mechanical ventilation.

The role of interleukin-6, endothelins, and apoptotic genes in small bowel transplantation, in a swine model of ischemia and reperfusion injury

IRI is closely related to sepsis in ITx setting. Complete understanding of the mechanisms involved in IRI development may improve outcomes. Ortothopic ITx without immunosuppression was performed in order to characterize IRI-associated mucosal damage. Twenty pigs underwent ITx. Two groups were assigned to different CI times: G1: 90 min and, G2: 180 min. Euro-Collins was used as preservation solution. Jejunal fragments were collected at donor laparotomy, 30 min, and 3 days after reperfusion. IRI assessment involved: histopathologic analysis, quantification of MPO-positive cells through immunohistochemical studies, quantification of epithelial apoptotic cells using TUNEL staining, and quantification of IL-6, ET-1, Bak, and Bcl-XL genes expression by RT-PCR. Neutrophilic infiltration increased in a similar fashion in both groups, but lasted longer in G2. Apoptosis detected by TUNEL staining increased and anti-apoptotic gene Bcl-XL expression decreased significantly in G1, 3 days after surgery. Endothelin-1 and IL-6 genes expression increased 30 min after the procedure and returned to baseline 3 days after surgery. In conclusion, IL-6 and ET-1 are involved precociously in the development of intestinal IRI. Apoptosis was more frequently detected in G1 grafts by TUNEL-staining and by RT-PCR.

Evaluation of the cytogenetic effects of I-131 preceded by recombinant human thyrotropin (rhTSH) in peripheral lymphocytes of Wistar rats

The present study was carried out to investigate the cytogenetic effects of therapeutic exposure to radioiodine preceded by rhTSH in an animal model. Three groups of Wistar rats (n = 6) were used: one group was treated only with I-131 (11.1 MBq/animal); the other two groups received rhTSH (1.2 mu g/rat of either Thyrogen or rhTSH-IPEN, respectively) 24 h before administration of radioiodine. The percentage of lymphocytes with chromosome aberrations and the average number of aberrations and of dicentrics per cell were determined on blood samples collected 24 h, 7 and 30 days after administration of I-131. The data show that the treatment with radioiodine alone or associated with rhTSH resulted in a greater quantity of chromosome alterations in relation to basal values after 24 h, with a gradual decline after 7 and 30 days of treatment. An increase in chromosome alterations was also seen after rhTSH treatment alone. Neither of the treatments, i.e., with I-131 alone or associated with hormone, resulted in an aneugenic effect or influenced the kinetics of cellular proliferation in rat blood lymphocytes. There was no significant difference between the cytogenetic effects of Thyrogen and rhTSH-IPEN treatment. These data suggest that the treatment with radioiodine, associated or not with rhTSH, affects to a limited extent a relatively small number of cells although the occurrence of late stochastic effects could not be discarded.

Late Gadolinium Enhancement Magnetic Resonance Imaging in the Diagnosis and Prognosis of Endomyocardial Fibrosis Patients

Background-Endocardial fibrous tissue (FT) deposition is a hallmark of endomyocardial fibrosis (EMF). Echocardiography is a first-line and the standard technique for the diagnosis of this disease. Although late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) allows FT characterization, its role in the diagnosis and prognosis of EMF has not been investigated. Methods and Results-Thirty-six patients (29 women; age, 54 +/- 12 years) with EMF diagnosis after clinical evaluation and comprehensive 2-dimensional Doppler echocardiography underwent cine-CMR for assessing ventricular volumes, ejection fraction and mass, and LGE-CMR for FT characterization and quantification. Indexed FT volume (FT/body surface area) was calculated after planimetry of the 8 to 12 slices obtained in the short-axis view at end-diastole (mL/m(2)). Surgical resection of FT was performed in 16 patients. In all patients, areas of LGE were confined to the endocardium, frequently as a continuous streak from the inflow tract extending to the apex, where it was usually most prominent. There was a relation between increased FT/body surface area and worse New York Heart Association functional class and with increased probability of surgery (P<0.05). The histopathologic examination of resected FT showed typical features of EMF with extensive endocardial fibrous thickening, proliferation of small vessels, and scarce inflammatory infiltrate. In multivariate analysis, the patients with FT/body surface area >19 mL/m(2) had an increased mortality rate, with a relative risk of 10.8. Conclusions-Our study provides evidence that LGE-CMR is useful in the diagnosis and prognosis of EMF through quantification of the typical pattern of FT deposition. (Circ Cardiovasc Imaging. 2011;4:304-311.)

Ecological aspects of the free-living ticks (Acari: Ixodidae) on animal trails within Atlantic rainforest in south-eastern Brazil

In a recent ecological study of the ticks on animal trails within an area of Atlantic rainforest in south-eastern Brazil, Amblyomma aureolatum, A. brasiliense, A. incisum, A. ovale and Haemaphysalis juxtakochi were found questing on the vegetation. Most of the ticks recorded by a small, man-made dam on the forest border were A. dubitatum but a few A. brasiliense and A. cajennense, one A. incisum and one H. juxtakochi were also found. The seasonal activity of the ticks indicated that A. incisum and A. brasiliense had one generation/year. On the animal trails, most tick species and stages quested on the vegetation at a height of 30-40 cm above ground level. The questing larvae and adults of A. incisum tended to be found higher, however, with the greatest numbers recorded 40-50 cm (larvae) or 60-70 cm (adults) above ground level. Most of the adult ticks (81.1% -100%), nymphs (78.6%-100%) and larval clusters (100%) found on a forest trail remained questing at the same location over a 24-h period. Carbon-dioxide traps in the rainforest attracted, 50% of the ticks observed questing on the nearby vegetation and, curiously, the CO(2) traps set deep in the forest attracted far fewer ticks than similar traps set by the dam. The ecological relationships between the ticks, their hosts and the rainforest environment are discussed.

Genetic diversity among Toxoplasma gondii isolates of small ruminants from Brazil: Novel genotypes revealed

Recent studies indicated that Toxoplasma gondii isolates of many domestic animal hosts from Brazil are genetically and biologically different from those in USA and Europe. Despite of high pathogenicity of this parasite to small ruminants, the epidemiology and genetic diversity of T. gondii in these animals are not well understood in Brazil. In this study, a total of 28 T. gondii samples (16 isolates from sheep in Sao Paulo state, and 12 isolates from goats in the states of Sao Paulo and Rio Grande do Norte) were genotyped using genetic markers SAG1, SAG2, SAG3, BTUB, CRAG, c22-8, c29-2, L358, PK1, Apico and CS3. Eleven genotypes were identified from these T. gondii isolates. Eight isolates (4 from sheep and 4 from goats) were grouped into the common clonal type Brl lineage. One sheep isolate was grouped to the type BrIII lineage. Five isolates grouped to three previously identified genotypes in Brazil, and 13 isolates grouped to six novel genotypes. Mixed genotype was found in one isolate from goat in Sao Paulo. No classical clonal Type I. II or III isolates were found, confirming previous reports that these clonal lineages are rare in Brazil. The allele types at the CS3 locus are strongly linked to mouse virulence of the parasite. The results of this study indicate that even though a large number of T. gondii genotypes have been identified from a variety of animal hosts in Brazil, high percentage of new genotypes are continuously identified from different animal species, suggesting extremely high diversity of T. gondii in the population. (C) 2010 Elsevier B.V. All rights reserved.