Biomedical subjects

F Gregori

Publications and source records attributed to F Gregori.

At least 19 recordsLinked to original sources

PubMed2006

Molecular analysis of Brazilian strains of bovine coronavirus (BCoV) reveals a deletion within the hypervariable region of the S1 subunit of the spike glycoprotein also found in human coronavirus OC43.

Bovine coronavirus (BCoV) causes enteric and respiratory dis- orders in calves and dysentery in cows. In this study, 51 stool samples of calves from 10 Brazilian dairy farms were analysed by an RT-PCR that amplifies a 488-bp fragment of the hypervariable region of the spike glycoprotein gene. Maximum parsimony genealogy with a heuristic algorithm using sequences from 15 field strains studied here and 10 sequences from GenBank and bredavirus as an outgroup virus showed the existence of two major clusters (1 and 2) in this viral species, the Brazilian strains segregating in both of them. The mean nucleotide identity between the 15 Brazilian strains was 98.34%, with a mean amino acid similarity of 98%. Strains from cluster 2 showed a deletion of 6 amino acids inside domain II of the spike protein that was also found in human coronavirus strain OC43, supporting the recent proposal of a zoonotic spill- over of BCoV. These results contribute to the molecular characterization of BCoV, to the prediction of the efficiency of immunogens, and to the definition of molecular markers useful for epidemiologic surveys on coronavirus-caused diseases.

Amino Acid Sequence↗

PubMed2006

Phylogenetic analysis of Anaplasma marginale strains from Paraná State, Brazil, using the msp1alpha and msp4 genes.

Anaplasma marginale is an obligate intraerythrocytic rickettsial pathogen (order, Rickettsiales: family, Anaplasmataceae) that causes bovine anaplasmosis. This disease is widely distributed in tropical and sub-tropical regions of the world and causes important economic losses to cattle production. Major surface protein (MSP)1a (msp1alpha gene) is one of the six MSPs identified on A. marginale from cattle, whose sequence and size vary according to the number of tandem 28- to 29-amino acid repeats. This study characterized the msp1alpha and msp4 genes obtained from three distinct Brazilian herds from the State of Paraná. Three strains of the msp1alpha and one strain of the msp4 gene were sequenced. The strains evaluated revealed PCR products of different size, representing three, five and six internal repeats. Sequence analyses confirmed the number of tandem sequence copies and revealed a high degree of sequence identity with strains from other Brazilian States, as well as strains from the USA, Europe and Israel. The msp1alpha DNA and amino acid sequences from A. marginale and DNA sequences of msp4 strains did not reveal distinct phylogeographical segregation. However, the amino acid sequences of msp4 demonstrated definite phylogeographical relationship. These results suggest that the amino acid sequences of msp4 should be used for phylogenetic identification of A. marginale strains and may be an important tool for the epidemiology and control of anaplasmosis. Additionally, the close similarity of the Paraná strains of A. marginale with strains from USA, Europe and Asia may reflect the introduction of these genes during the development of the Brazilian bovine herd.

Amino Acid Sequence↗

PubMed2000

Detection and differentiation of Leptospira spp. serovars in bovine semen by polymerase chain reaction and restriction fragment length polymorphism.

In view of the importance of venereal transmission of bovine leptospirosis, the objective of the present study was to apply the polymerase chain reaction (PCR) to 26 serovars of Leptospira interrogans, L. borgpetersenii, L. santarosai, L. noguchii and L. biflexa, to determine the detection threshold in semen samples and to evaluate the possibility of differentiation among serovars using 19 restriction endonucleases. The results showed that all serovars were amplified and the detection threshold in semen samples of a bull was 100 bacteria/ml. Using endonucleases we could classify the 26 serovars into eight groups. The present results show that PCR is a method of great potential for the detection of Leptospira spp. at bovine artificial insemination centers.

Animals↗

PubMed2000

Coronary bilateral ostial enlargement using the saphenous vein in a patient with syphilitic aortitis.

A patient with tertiary syphilis presenting with bilateral coronary ostial lesions and aortic regurgitation underwent surgical reconstruction of the coronary ostia by the anterior approach with autogenous saphenous vein grafting and substitution of the aortic valve with a bovine bioprosthesis. The procedure was easily performed and had good outcomes both early and late. The rarity of the association of a lesion in both coronary ostia with aortic regurgitation in syphilis and the surgical technique employed are discussed.

Aortic Valve↗

PubMed2000

Heart transplant in a patient with complete absence of the pericardium.

We report the case of a heart transplant in which the recipient patient had a total congenital absence of the pericardium. Associated with this, we found a major disproportion between the size of the recipient's mediastinal cavity and the size of the donor's heart. To prevent twisting of the great arteries, we placed the graft on the left diaphragm muscle and beneath the left lung, which resulted in an uneventful early and late postoperative course.

Adult↗

PubMed1999

Partial tricuspid valve transfer for repair of mitral insufficiency due to ruptured chordae tendineae.

BACKGROUND: A new technique is suggested for the reconstructive surgical treatment of mitral regurgitation. It involves partial transfer of the tricuspid valve of the patient to the mitral valve, in order to provide chordae to correct anterior leaflet prolapse of the mitral valve, secondary to rupture of the chordae tendineae. METHODS: From January 1991 to May 1997, 20 patients with mitral insufficiency due to rupture of the chordae were operated on. The prevailing cause was myxomatous degeneration (70%). Patients were in New York Heart Association functional class III and IV. RESULTS: There were no hospital deaths. Two patients were reoperated on. Eighteen patients (90%) are alive with their own valves (class I and II). Doppler echocardiogram mean values were: ejection fraction, 0.65; left atrial diameter, 4.2 cm; mitral area, 2.4 cm2; mitral transvalvular gradient, 3.3 mm Hg. No regurgitation or mild regurgitation was observed in 16 (94.1%) of the 17 cases evaluated. Mean tricuspid valvular area was 3.3 cm2. In all cases, no tricuspid regurgitation was present or it was mild. CONCLUSIONS: Partial transfer of the tricuspid valve to the mitral valve is an effective procedure for the surgical treatment of mitral valve insufficiency secondary to ruptured chordae tendineae of the anterior leaflet.

Adolescent↗

PubMed1999

Detection of leptospires in bovine semen by polymerase chain reaction.

OBJECTIVE: In view of the considerable importance of venereal transmission of bovine leptospirosis, the objective of the present study was to compare the polymerase chain reaction (PCR), culture/isolation and serology to detect leptospire infection in bovine semen. DESIGN: Blood for serologic examination and semen for bacterial culture and PCR were collected from 20 bulls at artificial insemination centres in Brazil. Each animal was sampled twice for serology. RESULT: Forty-five percent (9/20) of the serum samples collected showed agglutinin titers to serovar hardjo in the first sample and 25% (5/20) had agglutinin titers to serovar hardjo in the second sample. Eighty percent (16/20) of semen samples were positive by PCR. Leptospires could not be isolated from any of the semen samples examined. CONCLUSION: Polymerase chain reaction can be a method of great potential for the detection of leptospires at artificial insemination centres.

Animals↗

PubMed1996

Mitral valve repair.

Explore the source record for details and available documents.

Cardiac Surgical Procedures↗

PubMed1995

Cox maze operation without cryoablation for the treatment of chronic atrial fibrillation.

BACKGROUND: From August 1993 to May 1994, 20 patients (mean age, 43 years) with atrial fibrillation underwent the maze operation without cryoablation. Ten patients had mitral stenosis, 5 had mitral insufficiency, and 5 had a mixed mitral lesion. The mean left atrial diameter as measured on echocardiograms was 6.1 cm. The cause was rheumatic in 17 patients (85%) and degenerative in 3 (15%). Seven patients had had previous episodes of thromboembolism. METHODS: Mitral valvuloplasty was performed on 7 patients, mitral commissurotomy on 4, and mitral valve replacement on 9. Thrombi were found in the left atrium of 7 patients and also in the right atrium in 2. The mean cross-clamp time was 73 minutes (range, 52 to 108 minutes). RESULTS: Patients were discharged from the hospital in good condition. Hemodynamic studies and Doppler echocardiograms showed significant reduction in the left atrial diameter (mean diameter, 4.9 cm; p < 0.01) in 18 patients. The two-channel Holter monitor showed sinus rhythm in 15 patients, atrial ectopic rhythm in 4, and atrial fibrillation in 1. Eleven patients (55%) experienced atrial fibrillation (9 in the first 3 months postoperatively), which was reversed with quinidine. Ninety percent of patients had development of an effective, synchronous, atrial systole. Six to 15 months postoperatively (average follow-up, 10 months), all patients were in functional class I, and 18 were not on a regimen of antiarrhythmic medication. CONCLUSIONS: This simplification of the maze operation has been demonstrated to be an effective alternative for the treatment of chronic atrial fibrillation.

Adolescent↗

PubMed1994

Modified technique for total cavopulmonary connection.

The laterolateral anastomosis between the superior vena cava and the pulmonary artery trunk is presented as a modified technique for total cavopulmonary connection. This procedure was successfully performed on a 9-year-old girl, associated with the exclusion of the right atrium, for the treatment of tricuspid atresia and transposition of the great arteries.

Anastomosis, Surgical↗

PubMed1994

Mitral valvuloplasty with a new prosthetic ring. Analysis of the first 105 cases.

From October 1987 to March 1993, 105 patients were studied who have undergone valvuloplasty with an open ring. They ranged from 5 to 79 years (mean 30); 33 (31.4%) were under 16. All patients had mitral insufficiency, alone in 62 (59.0%) and associated with mitral stenosis (double mitral lesion) in 43 (41.0%). In the majority of the cases, the aetiology was rheumatic (78.1%); active in 10 (9.5%) patients. Three patients (2.9%) were in class II, 42 (40.0%) in class III, 57 (54.3%) in class IV and 3 (2.9%) in class V. Ten patients (9.5%) had isolated ring implantation while the remaining underwent associated procedures on the leaflets, chordae and papillary muscles. There were two (1.9%) hospital deaths, and six patients (5.7%) had to be reoperated. On the 30th (mean) postoperative day, 75 (71.4%) patients were reevaluated by catheterization, echo Doppler or both to confirm the effectiveness of the techniques employed. The mitral valve was functioning normally or with mitral regurgitation + in 63 (84.0%) patients, mitral regurgitation + + in 2 (2.7%), mitral regurgitation + + + in 5 (6.7%), mitral stenosis + in 4 (5.3%), and mitral stenosis + + in 1 (1.3%) patient. The results were therefore considered excellent in 63 (84.0%) patients with either normal mitral valve or mitral regurgitation +, good in 6 (8.0%) patients with mitral regurgitation + + and/or mitral stenosis +, and poor in 6 (8.0%) patients with mitral regurgitation + + + and/or mitral stenosis + +. Two deaths (1.9%) occurred within the first 7 months of follow-up. Patients were evaluated clinically 1-67 months postoperatively (mean 27):90 (85.7%) were in class I, 4 (3.8%) in class II, 4 (3.8%) in class III and 1 (1.0%) in class IV.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗

PubMed1994