Torsional behaviour of Reciproc and Reciproc blue instruments associated with their martensitic transformation temperatures.

AIM: To compare the martensitic transformation temperatures and torsional resistance behaviour of classic M-Wire Reciproc and Reciproc blue files (VDW, Munich, Germany). METHODOLOGY: M-Wire classic Reciproc R25 and Reciproc blue R25 instruments were used. Transformation temperatures were determined by differential scanning calorimetry (DSC-DSC 60, Shimadzu, Kyoto, Japan). Three samples with approximately 20 mg of each system were cooled to -120 °C and then heated to 100 °C and then cooled to -100 °C at a rate of 10 °C min-1 . The maximum torque values and angular deflection until fracture of new instruments (n = 10) were measured according to ISO 3630-1. Results were analysed statistically using the Student's t-test at a significance level of P < 0.05. RESULTS: DSC results revealed the absence of martensitic transformation for Reciproc instruments in the temperature range analysed. In both systems, the instruments were composed of a mixture of R-phase and austenite at room temperature. After torsional tests, Reciproc blue had significantly lower values for mean maximum torque at rupture (P < 0.05), although the angular deflection values were significantly higher than the Reciproc classic group (P < 0.05). CONCLUSIONS: Both Reciproc and Reciproc blue instruments were composed of a mixture of R-phase and austenite. Reciproc Blue instruments had a greater angle of rotation to fracture but a lower torque to failure than M-Wire Reciproc instruments.

In silico prediction of conserved vaccine targets in Streptococcus agalactiae strains isolated from fish, cattle, and human samples.

Streptococcus agalactiae (Lancefield group B; group B streptococci) is a major pathogen that causes meningoencephalitis in fish, mastitis in cows, and neonatal sepsis and meningitis in humans. The available prophylactic measures for conserving human and animal health are not totally effective and have limitations. Effective vaccines against the different serotypes or genotypes of pathogenic strains from the various hosts would be useful. We used an in silico strategy to identify conserved vaccine candidates in 15 genomes of group B streptococci strains isolated from human, bovine, and fish samples. The degree of conservation, subcellular localization, and immunogenic potential of S. agalactiae proteins were investigated. We identified 36 antigenic proteins that were conserved in all 15 genomes. Among these proteins, 5 and 23 were shared only by human or fish strains, respectively. These potential vaccine targets may help develop effective vaccines that will help prevent S. agalactiae infection.

Results following closure of ostium secundum atrial septal defects.

In a series of 41 patients of ASD (ostium secundum type) corrected by surgery, a clinical, radiological, electrocardiographic and echocardiographic follow-up study was performed. Good clinical results were obtained but some abnormalities can persist postoperatively: RV enlargement, dysrhythmias and mitral valve dysfunction.

Larva migrans within scalp sebaceous gland.

A case of larva migrans or serpiginous linear dermatitis on the scalp of a teenager is reported. An ancylostomid larva was found within a sebaceous gland acinus. The unusual skin site for larva migrans as well as the penetration through the sebaceous gland are highlighted. The probable mechanism by which the parasite reached the skin adnexa is discussed.

[A case of perforation of the interventricular septum with free wall rupture, in the acute phase of myocardial infarct, successfully treated with surgery]. / Um caso de perfuração do septo interventricular com rotura da parede livre, na fase aguda do enfarte do miocárdio, operado com sucesso.

The authors present a case of interventricular septal rupture with left ventricular free wall rupture post acute myocardial infarction operated on the third day after the onset of symptoms, by enfartectomy and application of a septal patch. Then, they compare this case with four cases referred in the literature, discussing the different and similar points between them. They emphasize the good results of this kind of surgery, but they also remark the need of an early diagnosis and surgery in these patients.

[Prognosis of postoperative aortic dissection. Assessment with magnetic resonance]. / Prognóstico da dissecção da aorta após cirurgia. Avaliação por ressonância magnética.

OBJECTIVE: To evaluate operated type A aortic dissection by Magnetic Resonance Imaging (MRI), in order to detect long-term complications and identify prognostic indexes of evolution. DESIGN: Prospective study with a three-year period of follow-up. Prognosis evaluation. SETTINGS: Outpatient Clinic at Hospital de Santa Maria and Magnetic Resonance Imaging Center at Hospital da Cruz Vermelha. PATIENTS: A sample of 37 patients submitted to type A aortic dissection surgery, included sequentially, after exclusion of those with contraindication to MRI. METHODS: Initial evaluation (clinical and MRI study) at 3 to 4 months and at 1, 2 and 3 years after surgery. The mean follow-up time was 39.3 +/- 2.9 months. We evaluated the following complications over the aorta (aortic graft and five segments of residual aorta) and the aortic valve: aneurysm, pseudoaneurysm, rupture, re-dissection, progressive aortic valve regurgitation, reoperation and death. The prognostic indexes analysed were: presence of residual flap; false lumen patency; presence of re-entry points; false lumen to aorta dimension ratio; initial aortic dimension; increase of aortic dimension. RESULTS: All patients, with the exception of three that died, remained asymptomatic. COMPLICATIONS: Aneurysm was detected in 45.9% of patients, located in one or more segments; rupture occurred in three patients, preceded by aneurysm and pseudoaneurysm development; moderate or severe aortic regurgitation was detected in 47.8% of patients. Prognostic indexes: 1. Aneurysm development in each segment yeilded a significant association with: presence of residual flap in the same and other segments; higher initial dimension of the same and other segments, with the exception of the abdominal segment; higher increase in dimension of the same and other segments, with the exception of the abdominal segment; 2. Moderate or severe aortic regurgitation development showed a tendency to association with higher increase in dimension of proximal ascending aorta. 3. No association was found between aneurysm and aortic regurgitation development. CONCLUSIONS: Patients operated for type A aortic dissection had a high incidence of late complications which lead to reoperation and in some cases death. The presence of a residual flap, increased aortic dimensions and higher increase rate of aortic dimensions were associated with a complicated evolution. MRI was a very useful technique for long-term monitoring and to identify prognostic indexes of evolution.