NOLEN-SCHIFFER ANOMALY AND RHO(0)-OMEGA MIXING

The Nolen-Schiffer anomaly is the long standing discrepancy between theory and experiment of binding energy differences of mirror nuclei. It appears that the anomaly is largely explained by the charge symmetry breaking force generated by the rho(0)-omega mixing. In this paper I discuss the effect of the rho(0)-omega mixing to the binding energy differences in relativistic models of the nucleus. I also discuss the issue of momentum dependence of rho(0)-omega mixing amplitude and present an alternative explanation of the anomaly based on the partial restoration of chiral symmetry in the nucleus.

Diagnosis of canine brucellosis: Comparison between serological and microbiological tests and a PCR based on primers to 16S-23S rDNA interspacer

A pair of primers directed to 16S-23S rDNA interspacer (ITS) was designed directed to Brucella genetic sequences in order to develop a polymerase chain reaction (PCR) putatively capable of amplifying DNA from any Brucella species. Nucleic acid extracts from whole-blood from naive dogs were spiked with decreasing amounts of Brucella canis RM6/66 DNA and the resulting solutions were tested by PCR. In addition, the ability of PCR to amplify Brucella spp. genetic sequences from naturally infected dogs was evaluated using 210 whole-blood samples of dogs from 19 kennels. The whole-blood samples collected were subjected to blood culture and PCR. Serodiagnosis was performed using the rapid slide agglutination test with and without 2-mercaptoethanol. The DNA from whole blood was extracted using proteinase-K, sodium dodecyl sulphate and cetyl trimethyl ammonium bromide followed by phenol-chloroform purification. The PCR was capable of detecting as little as 3.8 fg of Brucella DNA mixed with 450 ng of host DNA. Theoretically, 3.8 fg of Brucella DNA represents the total genomic mass of fewer than two bacterial cells. The PCR diagnostic sensitivity and specificity were 100%. From the results observed in the present study, we conclude that PCR could be used as confirmatory test for diagnosis of B. canis infection.

The Brazilian pediatric myelodysplastic cooperative group strategies: are they relevant to improve educational approach and correct diagnosis?

Brazil is a wide country with huge contrasts. Its peculiarities can highlight environmental factors that could influence the frequencies of different cancers. The standard treatment and results achieved from several different areas of the country may not be found in others. The establishment of a national cooperative group has the potential to improve outcomes. The The Brazilian Cooperative Group on Pediatric Patients with Myelodysplastic Syndrome (BCG-MDS-PED) was first organized in January 1997 as a working group of hematologists, pediatric oncologists, pediatric-hematologists, molecular biologists and other professionals in order to study pediatric (age < 18 years) MDS. Six distinct subcommittees constituted with members from several universities: cytology, histopathology, clinical, cytogenetics, molecular biology and epidemiology. The goals of the BCG-MDS-PED were: (i) to offer support for diagnosis and orientation for treatment; (ii) educational Support for the colleagues all over the country and (iii) research on pathogenesis and new approaches for pediatric MDS patients. There are socio-economical differences among the five regions of the country. The BCG-MDS-PED believes that it is absolutely necessary to Study the clinical, cellular, molecular and epidemiological aspects of MDS, taking in account these peculiar differences among populations and regions. Since 1997, 114 pediatric cases were referred to the BCG-MDS-PED from 21 centres. Seven Brazilian states have sent cases to the group, 31 patients were referred from universities, 73 patients from pediatric oncology units (foundations) and 10 patients came from private clinics. Some of these patients have been followed up and/or treated by the physician who referred them to the BCG-MDS-PED for confirmation of the initial diagnosis. The majority of these physicians have required orientation on diagnostic and treatment issues, as well as to complete cytogenetic and molecular studies. From these 114 patients, 64 patients were confirmed as MDS. We believe that, the more numerous the MDS-studied cases, the more experienced will be the referee group on clinical and laboratory features on childhood MDS in Brazil. (C) 2002 Published by Elsevier B.V. Ltd.

Application of synthetic peptides to the diagnosis of neurocysticercosis

We tested the possible diagnostic utility of five Taenia saginata oncosphere-derived synthetic peptides in T. solium neurocysticercosis (NC). The five peptides correspond to protein sequences with high antigenic indexes that were cloned from a T. saginata oncosphere cDNA library. The test samples consisted of cerebrospinal fluid (CSF) samples randomly collected from patients referred from Mexican and Brazilian neurological institutes. Indirect enzyme-linked immunosorbent assays (ELISA) were carried out with the peptides either unconjugated or coupled to carrier proteins, and were compared with results obtained using T. solium cyst fluid as a positive control. For active inflammatory NC, the higher sensibility (93%) and specificity (85%) was obtained with peptides HP6-2 and Ts45W-1, respectively, coupled to ovalbumin, in both Mexican and Brazilian patients. Examining the results of the individual peptide assays in combination, in some instances, improved the sensitivity to 100%.

A model for the Schottky anomaly in metallic Nd2-yCeyCuO4

We present a simple model for the doped compound Nd2-yCevCuO4, in order to explain some recent experimental results on the latter. Within a Hartree-Fock context, we start from an impurity Anderson-like model and consider the magnetic splitting of the Nd-4f ground state Kramers doublet due to exchange interactions with the ordered Cu moments. Our results are in very good agreement with the experimental data, yielding a Schottky anomaly peak for the specific heat that reduces its amplitude, broadens and shifts to lower temperatures, upon Ce doping. For overdoped compounds at low temperatures, the specific heat behaves linearly and the magnetic susceptibility is constant. A smooth transition from this Fermi liquid-like behavior occurs as temperature is increased and, at high temperatures, the susceptibility exhibits a Curie-like behavior. Finally, we discuss some improvements our model is amenable to incorporate, (C) 1998 Elsevier B.V. B.V. All rights reserved.

Unusual early morning development of the equatorial anomaly in the Brazilian sector during the Halloween magnetic storm

The solar events that occurred at the end of October 2003 gave rise to very strong geomagnetic disturbances that peaked twice with Dst values reaching -345 nT around 0000 UT on 30 October and -400 nT around 2300 UT, on the same day. Disturbances in several ionospheric parameters were observed over Brazil. This work will focus on the ionospheric response to the initial westward prompt penetration electric field and on the strong intensification of the equatorial ionization anomaly that occurred because of the electric field polarity reversal that followed in the early morning hours of 29 October. The F layer peak height over the equator first decreased under the strong prompt penetration westward electric field, which was followed by significant height increase under eastward electric field. We have used Sheffield University Plasmasphere Ionosphere Model (SUPIM) with an intensified westward disturbed electric field in the presunrise hours, presumably due to prompt penetration from the magnetosphere, in order to study the effect of such a field in the ionosphere. The simulation results showed that prompt penetration of magnetospheric electric fields of westward polarity to the nightside equatorial region seems to be the most probable cause of the initial F layer height decreases. The intensification of the equatorial ionization anomaly and the unusual enhancement on F layer peak density, which was not modeled by the SUPIM, are explained as caused by the strong eastward electric field that followed the initial phase in combination with a highly variable disturbed meridional/transequatorial wind system as inferred from the F2 layer peak height variations. The highly dynamic wind pattern, with a short-term response (2-4 hours), is compatible with the predictions of some previous theoretical model calculations reported in the literature.

Dental abnormalities in children after chemotherapy treatment for acute lymphoid leukemia

The frequency of dental abnormalities, such as delayed dental development, microdontia, hypoplasia, agenesis, V-shaped root and shortened root was evaluated in 76 acute lymphoblastic leukemia (ALL) pediatric patients who had been off chemotherapy for 6 months. These children had been subjected to one of the three Brazilian Protocols or the BFM86 Protocol. The patients were divided into three groups: Group I (GI; high risk) treated with one of the three Brazilian Protocols who received high-dose chemotherapy, intensive maintenance and cranial radiotherapy; Group II (GII; low risk) who were also treated with one of the three Brazilian Protocols using low-intensive chemotherapy with no radiotherapy; and Group III (GIII) based on the BFM86 Protocol.Of 76 children, 13 showed no dental abnormalities (8 were at the age of tooth formation). The remaining 63 children (82.9%) showed at least one dental anomaly.The abnormalities were probably caused by the type, intensity, frequency of the treatment and age of the patients at ALL diagnosis and this might have important consequences for the children's dental development. (C) 2002 Elsevier B.V. Ltd. All rights reserved.

Thermography and ultrasonography in back pain diagnosis of equine athletes

The object of the current study was to evaluate the efficacy of thermography and ultrasonography in the diagnosis of thoracolumbar lesions in Quarter Horse athletes and associate the different types of lesions found with the athletic modality practiced. Twenty-four horses were admitted to the Surgery Service for Large Animals of the Veterinary and Animal Science Faculty, UNESP, Botucatu, Brazil, with complaints of back problems. All the horses were submitted for physical examinations to confirm the existence of thoracolumbar alterations and then for thermography and ultrasonography Thermography was used to map the lesioned areas of this region and ultrasonography for lesion characterization. The lesions found were supraspinous desmitis, interspinous desmitis, dorsal intervertebral osteoarthritis, and impingement of the spinous processes or kissing spines. The existence of a relation between the type of event practiced by the horse and the type of lesion found was determined. In horses that competed in the barrel race, a predominance of lesions in the thoracic caudal, thoracolumbar, and cranial lumbar regions occurred, with intervertebral osteoarthritis and interspinous desmitis being the most common. In cutting horses, most of the lesions were observed in the caudal lumbar region, whereas horses competing in reining showed a preferential location for lesions in the middle lumbar, with a predominance of supraspinous desmitis and myositis. Thermography associated with ultrasonography was shown to be efficient in the diagnosis of the thoracolumbar lesions of these horses.