Biomedical subjects
B Miguel
Publications and source records attributed to B Miguel.
Recurrence of postoperative aortic fistulas: is there an ideal method of prevention? A case report.
There are very few cases in English literature of recurrent postoperative aortic fistulas (RPAFs). These are neo-communications between the aortic bloodstream and the lumen of contiguous organs which occur after unpredictable periods from surgical treatment of a previous fistula. The supradiaphragmatic aorta may fistulize into the airways, pulmonary circulation, oesophagus, and cardiac chambers; the infradiaphragmatic aorta into the intestine, stomach, and vena cava. According to the etiology, aortic fistulas are categorized as postoperative (or secondary) and spontaneous (or primary), and RPAF may be considered a subgroup of secondary fistulas. They may recur even more times in the same patient, hence the role of prevention is of the utmost importance. The simultaneous respect of different surgical principles is crucial to make the risk of recurrence less likely. Surgical treatment represents a real challenge due to the emergency conditions and redo nature of operations. Mortality rate is very high. In this article, we describe a case of recurrent aorto-duodenal communication, we discuss the principles of prevention both for the supra and infradiaphragmatic aorta, we introduce some modifications to the classic categorization and we present the first RPAF literature review.
The role of feline aminopeptidase N as a receptor for infectious bronchitis virus. Brief review.
Feline aminopeptidase N (fAPN) has been shown to serve as a receptor for feline, canine, porcine and human coronaviruses. Our objective was to determine if fAPN can serve as a receptor for infectious bronchitis virus (IBV). Feline kidney cells that express fAPN and hamster kidney fibroblasts that do not express fAPN were inoculated with IBV and monitored for replication by indirect fluorescent assay and confocal microscopy and in chicken embryonated eggs. The results showed that the feline cells were permissive to IBV but the hamster cells were not. The hamster cells became permissive to IBV after transfection with a fAPN cDNA suggesting that the feline APN molecule plays a role in IBV entry.
Spontaneous intramural left atrial hematoma associated with systemic amyloidosis.
Spontaneous intramural left atrial hematoma is very rare. We describe a case of spontaneous intramural left atrial hematoma that had to be semiurgently resected. Postoperatively, the patient was diagnosed as having systemic immunocyte-derived (AL) amyloidosis, because of rare manifestations of fatal bleeding. Though spontaneous intramural left atrial hematoma is one of the severe complications of systemic AL amyloidosis, we believe that amyloid deposits caused fragility of the left atrial wall.
Mitral and mitro-aortic valve replacement with Sorin Bicarbon valves compared with St. Jude Medical valves.
OBJECTIVE: We assessed the clinical results of two bileaflet mechanical valves: the St. Jude Medical (SJM) and the Sorin Bicarbon (Sorin Bicarbon) used either in single mitral valve replacement (MVR) or in double, aortic and mitral, valve replacement (DVR). METHODS: Between September 1990 and November 1995, 217 patients received either a St. Jude Medical (n=134) or a Sorin Bicarbon (n=86): 136 mitral valve replacement with 83 St. Jude Medical and 53 Sorin Bicarbon and 84 double valve replacement with 51 St. Jude Medical and 33 Sorin Bicarbon. There was no difference between both St. Jude Medical and Sorin Bicarbon cohorts in respect of mitral valve physiopathology, etiology of valve disease, associated lesions, echocardiographic and hemodynamic data. The only significant preoperative difference was the age of patients within the double valve replacement group and the size of implanted valves within the mitral valve replacement group. Follow-up was 100% complete with a mean of 39+/-18 months, ranging between 6 and 68 months. The total follow-up was 657 patient-years (pt-y): 396 pt-y in the mitral valve replacement group and 274 pt-y in the double valve replacement group. RESULTS: Hospital mortality (St. Jude Medical: 2.2%; Sorin Bicarbon: 6.9%) and late mortality (St. Jude Medical: 8.4%; Sorin Bicarbon: 6.3%) were not significantly different. Ten deaths were considered valve-related (St. Jude Medical 6, Sorin Bicarbon 4). The estimated 4-yr overall survival, including hospital mortality, was for St. Jude Medical--mitral valve replacement: 89+/-4% and St. Jude Medical--double valve replacement: 93+/-4%, and for Sorin Bicarbon--mitral valve replacement: 87+/-5% and Sorin Bicarbon--double valve replacement: 91+/-5%. The linearized incidence (% per pt-y) of valve-related complications was 6.39 in the St. Jude Medical cohort and 9.2 in the Sorin Bicarbon cohort. The linearized incidence (% pt-y) of the prevalent complication, valve thromboembolism and bleeding, was for St. Jude Medical-mitral valve replacement: 3.41, St. Jude Medical--double valve replacement: 3.16 and for Sorin Bicarbon--mitral valve replacement: 2.17 and Sorin Bicarbon--double valve replacement: 3.67. The differences between each group of an estimated 4-yr freedom from combined thromboembolism and bleeding were not significant (St. Jude Medical--mitral valve replacement: 90+/-4%, St. Jude Medical--double valve replacement: 84+/-6%, and for Sorin Bicarbon--mitral valve replacement: 94+/-3% and Sorin Bicarbon--double valve replacement: 75+/-17%). CONCLUSIONS: In this clinical non-randomized study, there was no evidence of any significant difference between St. Jude Medical and Sorin Bicarbon valves over a 4-yr follow-up.
Size evolution of the vibrational predissociation process in Br2...Nen clusters: simulation and kinetic study.
A hybrid quantum-classical simulation of the vibrational predissociation of Br2...Nen, (n = 2-11) clusters in the B electronic state is carried out. The time-evolution of the reactants, products, and intermediates is analyzed by a kinetic mechanism consisting of three elementary steps: direct vibrational predissociation (VP), intramolecular vibrational redistribution (IVR), and evaporative cooling (EC). The importance of intramolecular vibrational redistribution followed by evaporative cooling relative to direct vibrational predissociation is shown to increase rapidly with increasing cluster size. Final product state distributions reveal that only one or less Br2 stretching quantum per neon atom is required in order to achieve complete dissociation (n quanta for n < or = 9 and n - 1 for n = 10 and 11). The proportion of available energy going into translation is proposed as a parameter to study the statistical behavior of the Van der Waals clusters. It is shown to depend only on the number of remaining degrees of freedom, a characteristic of a statistical behavior, for n > or = 3.
[Treatment with aorto-iliac stents of acute lower limb ischemia in a patient complicating acute type B aortic dissection].
Treatment with aorto iliac endoprothesis of lower limb ischemia occuring in a patient with acute type B dissection. The mechanism was dynamic ischemia. The dissecting flap prolapsed into the iliac artery origin and narrowed the aortic true lumen above it, but without extension of the flap into the iliac artery lumen. After right iliac artery stenting, a relative left iliac artery ischemia by the shift of the dissection flap required stent implantation. Eight months later, the walking perimeter without pain was 1500m. The interest of endovascular techniques to treat visceral or lower limb ischemic complications in dissected aorta is discussed.
Coil embolization of a false aneurysm with aorto-cutaneous fistula after prosthetic graft replacement of the ascending aorta.
AIM: To report palliative embolization of a false aneurysm over the distal suture line of an ascending aorta graft replacement. MATERIAL AND METHOD: A 78-year-old male patient was admitted for increasing bleeding of a chronic Manubrium ulceration, 20 months after coronary artery bypass complicated by perioperative ascending aorta dissection requiring prosthetic graft replacement. One month later, he underwent epiploplasty for a mediastinitis followed by long-term antibiotic therapy. Five months later, he presented with a Manubrium ulceration of the sternotomy. Spiral computerized tomography (CT) and aortography revealed a 20 mm anterior peri-prosthetic false aneurysm with a wide neck. Advanced age, active mediastinitis and patient's objection led us to perform percutaneous occlusion according to the Moret remodeling technique while protecting the coils release with balloon catheter inflation. RESULTS: No post-operative complication was observed and at 1-year follow-up the patient was doing well with no recurrent bleeding. Magnetic resonance imaging (MRI) and spiral CT controls confirmed coils stability without any internal flow. CONCLUSION: Percutaneous coils embolization of a large false aneurysm in the ascending aorta can be a palliative treatment in a surgically unsuited patient.
[Kidney cancers with supra-diaphragmatic invasion. Surgical treatment using extracorporal circulation with heart arrest].
STUDY AIM: The study aim was to report results of nephrectomy with resection of cavo atrial thrombus in 6 patients with a renal carcinoma and supra-diaphragmatic vena cava extension and to discuss limits of the surgical indications. PATIENTS AND METHOD: Six patients, five adults (mean age: 57 +/- 10 years) and a four-year old girl, were operated on for a renal cell carcinoma with supra-diaphragmatic vena cava extension. The venous extension was detected in all cases by abdominal ultrasonography. The superior extent of the thrombus was effectively visualized by CT scan in three cases, and by ultrasonography and magnetic resonance imaging in all cases. All the patients were operated on, using cardio-pulmonary bypass, without circulatory arrest, four in normothermia, two in moderate hypothermia at 28 degrees C. RESULTS: Hospital mortality was 0%. Average intensive care unit stay was 3.8 days. During the following period, all the patients developed metastatic disease. Mean survival rate of the five adult patients who had loco-regional invasion was 9.4 months (range: 6 to 19). The young girl underwent a wedge excision of two pulmonary metastases one year later and was still alive 7 years later. CONCLUSIONS: With cardio-pulmonary bypass, surgical resection of cavo-atrial thrombi may be performed with a low mortality and morbidity rate but late results were disappointing. Surgery should be limited to patients without loco-regional invasion or distant metastatic disease, and therefore accurate preoperative staging is mandatory.
Flexible posterior mitral annuloplasty: five-year clinical and Doppler echocardiographic results.
BACKGROUND: Stabilization of the posterior annulus seems to be a critical factor to achieve a stable mitral valve repair. To assess the benefit of softer mural annuloplasty, we analyzed results obtained with the flexible linear reducer. METHODS: From 1985 to 1993, 120 patients, with pure mitral regurgitation, mainly degenerative, had a mitral reconstruction. Mean age was 64+/-11 years and 74% of the patients were in New York Heart Association functional class III or IV. RESULTS: Hospital mortality was 3.3%. Mean follow-up was 56+/-24 months. There were 23 late deaths; 10 valve-related including 7 sudden deaths. Two patients (1.7%) required a reoperation. Doppler echocardiographic studies revealed excellent valve function; 5-year freedom from significant regurgitation was 85.8%+/-5.4%. Mean mitral valve area was 2.76+/-0.77 cm2. Although 105 patients were in class I or II, 23 patients were not functionally improved. Previous myocardial infarction and shorter deceleration time of early filling were risk factors for worsening functional disability. CONCLUSIONS: This support provides stable repair with excellent clinical and echographic results. Previous myocardial infarction and noncompliant left ventricle negatively influence outcome.
Surgical correction of the hypoplastic aortic arch by the subclavian free flap method in the neonate.
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Combining coupled-cluster and perturbative expansions through intermediate Hamiltonians: Theory and application to 1D and 2D spin lattices.
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[Optimum time of insulin therapy in type I diabetes mellitus].
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Comparison of the immunofluorescent assay and reverse transcription-polymerase chain reaction to detect and type infectious bronchitis virus.
Indirect fluorescent antibody (IFA) assay and reverse transcription-polymerase chain reaction (RT-PCR) are two current methods commonly used for the detection of infectious bronchitis virus (IBV) and its serotypes. The objectives of this study were to compare the two methods relative to detecting IBV in chicken embryos that were artificially inoculated with Mass41, Ark99, or Mass41/Ark99 in serial embryo passages and in tracheas and cecal tonsils collected from vaccinated commercial flocks with and without respiratory problems. The tissues collected from these birds were used to inoculate chicken embryos. The chorioallantoic membranes collected from the inoculated embryos were examined by the IFA assay, and the allantoic fluids collected from the same embryos were subjected to the RT-PCR. The IFA assay and RT-PCR both were able to detect and type IBV when only one IBV strain was inoculated into embryos, regardless of the number of passages. When embryos were inoculated with Mass41 and Ark99 strains simultaneously, both strains were 100% detected by the RT-PCR. By the IFA assay, 20% of samples were positive for two strains and 80% were positive for the Ark only. Two of eight samples collected from healthy flocks that were vaccinated with Mass/Conn/Ark were positive by the IFA assay, and four of eight were positive by the RT-PCR. Sixteen percent (12/75) of the samples from birds experiencing respiratory problems were positive by the IFA assay and 35% (26/75) were positive by the RT-PCR. Results suggest that the RT-PCR is more sensitive than the IFA assay, especially when more than one strain of IBV is involved, but the IFA assay is rapid and cheaper than the RT-PCR.
Distribution of arthritis and osteomyelitis in turkeys with green liver discoloration.
The distribution of arthritis and osteomyelitis (OM) was studied in turkeys with green liver (GL) discoloration collected in a processing plant; the turkeys originated from seven commercial farms. Overall occurrence of GL, arthritis, and OM in the 25,320 inspected toms was 264 (1.04%), 123 (0.49%), and 107 (0.42%), respectively, and in the 16,690 inspected hens was 24 (0.14%), 0%, and 13 (0.08%), respectively. Prevalence of GL, OM, and arthritis varied among the studied farms. Arthritis and/or OM were detected in 168 (58.3%) of 288 turkeys with green discolored livers. Of the 168 turkeys with OM and/or arthritis, 48 (28.6%) had only arthritis, 45 (26.8%) had OM only, and 75 (44.6%) had both lesions. Arthritis and OM were detected in single and multiple sites and were unilateral and bilateral. Distribution of OM in the 120 OM-positive turkeys with and without arthritis was 77 (64.2%) in proximal tibia, 29 (24.2%) in proximal humerus, 28 (23.3%) in proximal femur, 13 (10.8%) in rib cage, and 4 (3.3%) in distal femur. Distribution of arthritis in the 123 arthritis-positive turkeys with and without OM was 77 (62.6%) in shoulder, 45 (36.6%) in stifle, and 25 (20.3%) in hip joints. Findings in this study suggest that arthritis and osteomyelitis are two distinct lesions and that they may develop independently in the same bird.
Subacute to chronic fowl cholera in a flock of Pharaoh breeder quail.
A total of 1300 birds in flock of breeder Pharaoh quail (Coturinix coturnix) experienced a moderate rate of mortality (13%) during a 7-day period. Clinical signs included depression, ruffled feathers, prostration, lameness, inapetence, diarrhea, and periorbital sinus swelling with mucoid discharge and lameness. Gross lesions observed in dead quail were emaciation, carcass congestion, mild hepatomegaly with green discoloration, congested intestinal mucosa, caseous purulent arthritis-osteomyelitis, and thickened crop mucosal epithelium. Histopathologic examination revealed mild hepatic amyloidosis, proliferative parabronchitis, splenic reticular cell hyperplasia, thymic cortical atrophy, subacute bacterial osteomyelitis, periarthritis, and crop mycosis. Pasteurella multocida was isolated from the joints of these birds and the isolates were serotype 3 x 4. These findings suggest that Pharaoh quail are susceptible to P. multocida and are likely to develop subacute to chronic fowl cholera.