RF generation using a compact bench gyromagnetic line.

The search for new technologies aiming to reach radiofrequency (RF) generation in different manners for diverse ends is a constant demand for several applications. The goal is to develop cost-effective and simpler systems compared to those that already exist. Our motivation is to reach an alternative way of generating RF in pulsed transmission systems employing a gyromagnetic nonlinear transmission line (GNLTL). The GNLTL consists of a ferrite-loaded-coaxial transmission line and can produce a large frequency spectrum with RF conversion efficiency above 10% from about 200 MHz up to the frequency of 2-4 GHz (S-band) for potential space-based applications. In a GNLTL, the signal amplitude is related to its propagation velocity since the peak voltage travels faster than its portion of lower amplitudes since the ferrite permeability decreases with the current amplitude. As the pulse crest travels faster than its valley, a time reduction happens in the output rise time, called pulse sharpening. Besides, the magnetic moments of ferrite dipoles initially aligned with the axial magnetic bias are displaced from their original position by the azimuthal field generated around the inner conductor by the current pulse, resulting in a damped precession movement. This movement happens along the line length as the current pulse propagates, inducing high-frequency oscillations. In short, the paper's goal is to present the experimental results using a 60-cm gyromagnetic line to provide RF in the GHz range using a solenoid for magnetic bias on a testing bench. Finally, the paper discusses the influence of the azimuthal and the axial magnetic fields on the output signal with the ferrite rings operating in a saturation state during the current pulse propagation.

Identification of a novel protein in the genome sequences of Leptospira interrogans with the ability to interact with host's components.

BACKGROUND: Leptospirosis is an infectious disease that affects humans and animals worldwide. The etiological agents of this disease are the pathogenic species of the genus Leptospira. The mechanisms involved in the leptospiral pathogenesis are not full understood. The elucidation of novel mediators of host-pathogen interaction is important in the detection of virulence factors involved in the pathogenesis of leptospirosis. OBJECTIVE: This work focused on identification and characterization of a hypothetical protein of Leptospira encoded by the gene LIC10920. METHODS: The protein of unknown function was predicted to be surface exposed. Therefore, the LIC10920 gene was cloned and the protein expressed in Escherichia coli BL21 (DE3) Star pLysS strain. The recombinant protein was purified by metal affinity chromatography and evaluated with leptospirosis human serum samples. The interaction with host components was also performed. RESULTS: The recombinant protein was recognized by antibodies present in leptopsirosis human serum, suggesting its expression during infection. Immunofluorescence and intact bacteria assays indicated that the bacterial protein is surface-exposed. The recombinant protein interacted with human laminin, in a dose-dependent and saturable manner and was named Lsa24.9, for Leptospiral surface adhesin, followed by its molecular mass. Lsa24.9 also binds plasminogen (PLG) in a dose-dependent and saturable fashion, fulfilling receptor ligand interaction. Moreover, Lsa24.9 has the ability to acquire PLG from normal human serum, exhibiting similar profile as observed with the human purified component. PLG bound Lsa24.9 was able of generating plasmin, which could increase the proteolytic power of the bacteria. CONCLUSIONS: This novel leptospiral protein may function as an adhesin at the colonization steps and may help the invasion process by plasmin generation at the bacterial cell surface.

Implementation of a Brazilian Cardioprotective Nutritional (BALANCE) Program for improvement on quality of diet and secondary prevention of cardiovascular events: A randomized, multicenter trial

Background Complex percutaneous coronary intervention (PCI) is associated with higher ischemic risk, which can be mitigated by long-term dual antiplatelet therapy (DAPT). However, concomitant high bleeding risk (HBR) may be present, making it unclear whether short- or long-term DAPT should be prioritized. Objectives This study investigated the effects of ischemic (by PCI complexity) and bleeding (by PRECISE-DAPT [PRE dicting bleeding Complications in patients undergoing stent Implantation and Sub sequent Dual Anti Platelet Therapy] score) risks on clinical outcomes and on the impact of DAPT duration after coronary stenting. Methods Complex PCI was defined as ≥3 stents implanted and/or ≥3 lesions treated, bifurcation stenting and/or stent length >60 mm, and/or chronic total occlusion revascularization. Ischemic and bleeding outcomes in high (≥25) or non-high (<25) PRECISE-DAPT strata were evaluated based on randomly allocated duration of DAPT. Results Among 14,963 patients from 8 randomized trials, 3,118 underwent complex PCI and experienced a higher rate of ischemic, but not bleeding, events. Long-term DAPT in non-HBR patients reduced ischemic events in both complex (absolute risk difference: −3.86%; 95% confidence interval: −7.71 to +0.06) and noncomplex PCI strata (absolute risk difference: −1.14%; 95% confidence interval: −2.26 to −0.02), but not among HBR patients, regardless of complex PCI features. The bleeding risk according to the Thrombolysis In Myocardial Infarction scale was increased by long-term DAPT only in HBR patients, regardless of PCI complexity. Conclusions Patients who underwent complex PCI had a higher risk of ischemic events, but benefitted from long-term DAPT only if HBR features were not present. These data suggested that when concordant, bleeding, more than ischemic risk, should inform decision-making on the duration of DAPT. (AU)

Structural organization of the enteric nervous system in the cattle esophagus revealed by wholemount immunohistochemistry.

In ruminants the motility patterns of the esophageal tube are characterized by physiological regurgitations including both anterograde and retrograde peristaltic movements. These complex motor functions require an elaborated enteric nervous system (ENS) for the generation of the underlying intrinsic reflex circuits. The structural organization of the esophageal ENS was studied in fetuses of cattle (n=6) by means of wholemount preparations obtained from different segments of the esophagus. Demonstration of nerve cells, ganglia and nerve fibers strands (NFS) was achieved by immunohistochemistry using the general neuronal marker protein gene product (PGP) 9.5. The myenteric plexus represented the most prominent nerve network composed of differently shaped ganglia and interconnecting NFS. Frequenitly the myenteric ganglia were arranged in two separate layers interweaving with the adjacent muscle coat. From the cervical towards the thoracic segment of the esophagus the density and size of myenteric ganglia increased and the NFS exhibited thicker diameters. The submucosal and mucosal plexus consisted of NFS ramifying throughout the tela submucosa and the lamina propria mucosae. The networks showed no evidence of ganglia nor single nerve cells. The findings illustrate that intrinsic esophageal nerve cells are confined to the myenteric plexus. Since the esophageal tube has no secretory functions, secreto-motor neurons are not required in the submucosal and mucosal plexus layers. The structural organization of the intramural nerve networks--in particular the specific arrangement of the myenteric plexus--reflects the substantial contribution of the esophageal ENS to the coordination and mediation of esophageal motility in ruminants.

The microangioarchitecture of the conducting system in cattle.

Macroscopic researches on heart vascularization have indicated that the angioarchitecture of the conducting system differs from that of the normal myocardium. In order to observe this variance, eight cow hearts were dissected for perfusion through the Ramus ventricularis dexter and Ramus septalis of the A. coronaria dextra with Ringer's solution, and then injected with Mercox. After corrosion in KOH the casts were prepared for observation in a SEM. In the region of the sinoatrial node no special capillary arrangement was observed, but only valves on the venous side. At the atrioventricular node and the bundle of His, the arterioles showed a diffuse formation, filling this area with a regular caliber, without any special capillary orientation. The arteries that reach the right bundle dichotomized and ran collateral to the opposite extremity of this structure, lying parallel. The vessels with the biggest caliber were deeply positioned. In the left bundle the arterioles showed a net like figure, mainly in one plane. Following the form of the bundle, and below the conducting tissue a big anastomotic venous arrangement is observable.

Structural differences of the enteric nervous system in the cattle forestomach revealed by whole mount immunohistochemistry.

The specific motility patterns of the forestomach of ruminants, composed of three structurally distinct compartments (rumen, reticulum, omasum), require an elaborate intramural innervation. To demonstrate the complex structure of the enteric nervous system (ENS), whole mount preparations obtained from different sites of the bovine forestomach were submitted to immunohistochemical procedures in which neuronal (protein gene product 9.5, neurofilament 200) and glial (protein S-100, glial fibrillary acid protein) markers were applied. Immunohistochemistry performed on whole mounts allowed a detailed two-dimensional assessment of the architecture of the intramural nerve networks. Generally, the myenteric and submucosal plexus layers were composed of ganglia and interconnecting nerve fiber strands, whereas the mucosal plexus consisted of an aganglionated nerve network. However, the texture of the ENS showed considerable regional differences concerning the ganglionic size, shape and density and the arrangement of nerve fiber strands. The myenteric plexus of the ruminal wall, showing a low ganglionic density and wide polygonal meshes, contrasted with the nerve network within the ruminal pillar which consisted of ropeladder-like nerve fiber strands and parallel orientated ganglia. The highest ganglionic density was observed at the reticular groove, the most prominent ganglia were found within the omasal wall. Branches of the vagal nerve frequently ramified within the myenteric plexus layers. The submucosal plexus of the rumen was divided into an external and internal layer; the reticular submucosal plexus followed the cristae and cellulae reticuli, the omasal submucosal (sublaminar) plexus showed intra- and parafascicular ganglia apart from ganglia located at the junctions of the nerve network. The mucosal plexus of the rumen consisted of thin nerve fascicles ramifying between the ruminal papillae, and reticular mucosal nerve fibers passed throughout the base of the cellulae reticuli. The highly specialised nerve network of the intralaminar omasal plexus showed radial and transverse trajectories reflecting the spatial arrangement of the intralaminar musculature. The demonstrated structural complexity of the ENS reflects the functional complexity of the ruminant forestomach and indicates the relatively high degree of autonomy in coordinating the different motility patterns required for the processing of the ingesta.

Análise genotípica do exon IV do gene da k-caseína de bubalinos (Bubalus bubalis) / Genotypic analysis of the exon IV of the buffaloes k-casein gene (Bubalus bubalis)

Amostras de sangue de duas raças de Bubalus bubalis, Murrah (n=30) e Mediterrâneo (n=14), e mestiços (Murrah/Mediterrâneo n=52), foram genotipadas quanto ao locus da k-caseína. As variantes A e B foram identificadas por meio da análise dos polimorfismos de comprimento de fragmentos de restriçäo (RFLPs) utilizando-se as enzimas Taq I e Hind III, após amplificaçäo de 99 pares de bases do exon IV pela reaçäo em cadeia da polimerase (PCR), com "primers" específicos para este gene de bovinos. Em relaçäo à Taq I, os fragmentos de DNA de bubalinos apresentaram tamanhos correspondentes ao de bovinos, sendo que as freqüências dos alelos A e B foram, respectivamente, 1,0 e 0 em Murrah e Mediterâneo e 0,99 e 0,01 em mestiços. O uso de Hind III revelou polimorfismo no gene de bubalino, diferente daquele encontrado em bovinos, apresentando os alelos C e D as freqüências de 0,45 e 0,55 em Murrah, 0,21 e 0,79 em Mediterrâneo e 0,28 e 0,72 em mestiço