Influência do posicionamento radiográfico no cálculo interobservador do ângulo do platô tibial em cães / Influence of radiographic positioning in the interobserver measuring of the tibial plateau angle in dogs

O objetivo deste trabalho foi demonstrar que o posicionamento radiográfico inadequado do membro pélvico de cães (imagens obliquadas) afeta a mensuração do ângulo do platô tibial (APT), levando à maior variação entre observadores. Foram realizadas duas projeções radiográficas nos membros pélvicos direito e esquerdo, uma em perfil verdadeiro e a outra com o membro obliquado em 21 cães provenientes do atendimento clínico cirúrgico do Hospital Veterinário da Universidade de Cuiabá, em Cuiabá-MT. Os critérios de inclusão foram cães livres de histórico ou afecção ortopédica nos membros pélvicos, pesando entre 15 e 40 quilos, sem predileção por raça ou sexo, entre dois e sete anos de idade. Foram obtidas 42 imagens radiográficas em perfil verdadeiro e 42 imagens radiográficas obliquadas. Três observadores com experiência em cálculo do APT fizeram as mensurações. Nos cálculos das imagens em perfil verdadeiro, o observador 1 obteve uma média de 23,35º ± 2,82; o observador 2, média de 23,88º ± 4,83; e o observador 3, média de 24,54º ± 4,01, não sendo encontrada diferença significativa entre o cálculo dos três avaliadores, P=0,944 (P > 0,05), nas imagens em perfil verdadeiro. Nos cálculos das imagens obliquadas, o observador 1 obteve uma média de 21,69º ± 4,22; o observador 2, média de 19,42º ± 5,92; e o observador 3, média de 22,64º ± 5,23, e foi encontrada diferença significativa entre o cálculo dos três observadores, P=0,016 (P < 0,05). Com esses dados, pôde-se demonstrar que a imagem radiográfica obliquada compromete o valor final do cálculo do ângulo do platô tibial em cães, levando à variação numérica estatisticamente significativa entre observadores. Conclui-se, assim, que um posicionamento correto do membro pélvico, em perfil verdadeiro, deve ser sempre utilizado para a obtenção de imagens, com o objetivo de mensurar o valor do APT.(AU)

This work aimed at demonstrating that an inadequate radiographic position of pelvic limbs of dogs, from a strict lateral radiographic view, resulted in oblique images, affecting the measurement of the tibial plateau angle (TPA). There were two radiographic projections of the right and the left pelvic limb, one in strict lateral radiographic view and another with inclined hind limb in 21 dogs from the clinical surgical assistance at Hospital Veterinário of Universidade de Cuiabá in Cuiabá-MT. Inclusion criteria were dogs free from pelvic hind limbs orthopedic affection records, weighing between 15 and 40 kilos, without a preference for breed or gender and ageing between two and seven years old. A total of 42 radiographic images in strict lateral radiographic view and 42 inclined limb radiographic views were obtained. Three observers with TPA calculation experience made measurements. In the calculus for the strict lateral radiographic view the first observer has reached an average of 23,35º ± 2,82, the second observer 23,88º ± 4,83 and the third observer 24,54º ± 4,01. No significant statistic differences among the calculus of the three evaluators p=0,944 (P>0,05) was found. In the calculus of the inclined limbs radiographic views the first observer reached an average of 21,69º ± 4,22, the second observer 19,42º ± 5,92 and the third observer 22,64º ±. 5,23. Significant statistic difference in the calculus of the three observers, p=0,016, that is to say, P<0,05 was found. The data indicated that the inclined limb radiographic image compromises the final value of the calculation of tibial plateau angle in dogs. Thus, correct positioning of the pelvic limb, in a strict lateral radiographic view, must be always used for obtaining images aiming at measuring the value of TPA.(AU)

Orthotopic liver transplantation without venovenous bypass using the conventional and piggyback techniques.

INTRODUCTION: Orthotopic liver transplantation is a widely used procedure for the treatment of irreversible liver diseases for which there is no possibility of medical treatment. When this procedure is performed by the conventional technique, the retrohepatic vena cava is removed along with the native liver. The inferior vena cava (IVC) remains clamped until the revascularization of the graft, and in this period there is a reduction in the venous return, which may induce a fall by up to 50% in the cardiac output with hemodynamic instability and a fall in renal perfusion pressure. The use of a portal-femoral-axillary venovenous bypass system, in which the blood from the femoral and portal veins returns to the heart via the axillary vein propelled by a centrifugal pump, is intended to minimize the effects of the IVC clamping. In the piggyback (PB) technique, the native liver is removed and the IVC of the recipient is preserved and only partially clamped. We have employed both techniques without the use of venovenous bypass for 10 years. The objective of this study was to compare the results obtained from the use of the two techniques. PATIENTS AND METHODS: A retrospective analysis was performed of 195 patients transplanted between 1999 and 2008: 125 by the conventional technique and 70, the PB technique. The intraoperative parameters were analyzed (surgical time, ischemia time, use of blood products, and diuresis), as well as intensive care support (duration of stay in intensive care unit and use of vasoactive drugs), period of intubation, length of hospital stay, renal function, graft function, postoperative complications, retransplantation, and patient survival. RESULTS: The PB group showed a reduction in surgical time, warm ischemia time, the use of packed red blood cells concentrates, and fresh frozen plasma, as well as mortality at 30 days (P<.05). There were no differences in relation to cold ischemia time, intraoperative diuresis; length of stay and use of vasoactive drugs in the intensive care unit; the period of intubation; the duration of hospital stay; the renal function; the graft function; the need for reoperation; the incidence of sepsis, biliary complications, vascular complications; need for retransplantation; and 1-year mortality. The cumulative survival rate at 1 year was significantly better among the PB patients. CONCLUSION: Orthotopic liver transplantation can be performed without venovenous bypass with good results, using either the conventional technique or the PB technique. Provided that there is no technical contraindication and a long ischemia period is not foreseen, the PB technique should be the technique of choice.

The 'strict' anaerobe Desulfovibrio gigas contains a membrane-bound oxygen-reducing respiratory chain.

Sulfate-reducing bacteria are considered as strict anaerobic microorganisms, in spite of the fact that some strains have been shown to tolerate the transient presence of dioxygen. This report shows that membranes from Desulfovibrio gigas grown in fumarate/sulfate contain a respiratory chain fully competent to reduce dioxygen to water. In particular, a membrane-bound terminal oxygen reductase, of the cytochrome bd family, was isolated, characterized, and shown to completely reduce oxygen to water. This oxidase has two subunits with apparent molecular masses of 40 and 29 kDa. Using NADH or succinate as electron donors, the oxygen respiratory rates of D. gigas membranes are comparable to those of aerobic organisms (3.2 and 29 nmol O(2) min(-1) mg protein(-1), respectively). This 'strict anaerobic' bacterium contains all the necessary enzymatic complexes to live aerobically, showing that the relationships between oxygen and anaerobes are much more complex than originally thought.

Acidianus ambivalens Complex II typifies a novel family of succinate dehydrogenases.

Complex II from the thermoacidophilic archaeon Acidianus ambivalens, an archetype of an emerging class of succinate dehydrogenases (SDH), was extracted from intact membranes and purified to homogeneity. The complex contains one molecule of covalently bound FAD and 10 Fe atoms. EPR studies showed that the complex contains the canonical centres S1 ([2Fe-2S]2+/1+) and S2 ([4Fe-4S]+2/+1) but lacks centre S3 ([3Fe-4S]+1/0); these observations agree with the fact that the iron-sulfur subunit contains an extra cysteine that may allow the binding of a new centre, most probably a tetranuclear one. Succinate-driven oxygen consumption is observed in intact membranes indicating that in vivo, complex II operates as a succinate:quinone oxidoreductase, despite missing the typical anchor domain subunits. The pure complex was found to contain bound caldariella quinone, the enzyme physiological partner. An alternative membrane anchoring for this new type of SDHs, based on the amphipathic nature of the putative helices found in SdhC, is suggested.

The unusual iron sulfur composition of the Acidianus ambivalens succinate dehydrogenase complex.

The succinate dehydrogenase complex of the thermoacidophilic archaeon Acidianus ambivalens was investigated kinetically and by EPR spectroscopy in its most intact form, i.e., membrane bound. Here it is shown that this respiratory complex has an unusual iron-sulfur cluster composition in respect to that of the canonical succinate dehydrogenases known. The spectroscopic studies show that center S3, the succinate responsive [3Fe-4S]1+/0 cluster of succinate dehydrogenases, is not present in membranes prepared from aerobically grown A. ambivalens, nor in partially purified complex fractions. On the other hand, EPR features associated to the remaining centers, clusters S1 ([2Fe-2S]1+/2+) and S2 ([4Fe-4S]2+/1+), could be observed. Similar findings were made in other archaea, namely Acidianus infernus and Sulfolobus solfataricus. Kinetic investigations showed that the A. ambivalens enzyme is reversible, capable of operating as a fumarate reductase - a required activity if this obligate autotroph performs CO2 fixation via a reductive citric acid cycle. Sequencing of the sdh operon confirmed the spectroscopic data. Center S3 ([3Fe-4S]) is indeed replaced by a second [4Fe-4S] center, by incorporation of an additional cysteine, at the cysteine cluster binding motif (CxxYxxCxxxC-->CxxCxxCxxxC). Genomic analysis shows that genes encoding for succinate dehydrogenases similar to the ones here outlined are also present in bacteria, which may indicate a novel family of succinate/fumarate oxidoreductases, spread among the Archaea and Bacteria domains.

Comparison of methods for HIV isolation from monocytes and lymphocytes of seropositive asymptomatic hemophiliacs and homosexuals.

1. Since monocyte-macrophages have been recognized as HIV targets in addition to CD4+ T-lymphocytes, we have evaluated HIV infection of purified peripheral blood mononuclear cell fractions obtained from 10 seropositive asymptomatic hemophiliacs and compared it with that of 10 asymptomatic homosexual patients. 2. HIV was isolated more frequently from the lymphocytes than the monocytes of both groups of patients. 3. HIV preferentially replicated in phytohemagglutinin-stimulated lymphocytes compared with growth factor-treated monocytes. Monocytes did not preferentially harbour HIV in either group.

Comparison of methods for HIV isolation from monocytes and lymphocytes of seropositive asymptomatic hemophiliacs and homosexuals

1. Since monocyte-macrophages have been recognized as HIV targets in addition to CD4+ T-lymphocytes, we have evaluated HIV infection of purified peripheral blood mononuclear cell fractions obtained from 10 seropositive asymptomatic hemophiliacs and compared with that of 10 assymptomatic homosexual patients. 2. HIV was isolated more frequently from the lymphocytes than the monocytes of both groups of patients. 3. HIV preferential replicated in phytohemagglutinin-stimulated lymphocytes compared with growth factor-treated monocytes. Monocytes did not preferentially harbour HIV in either group