Exogenous lipid pneumonia.
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Aged, 80 and over↗
Biomedical subjects
Lara Chalabreysse
Publications and source records attributed to Lara Chalabreysse.
[Wegener's granulomatosis].
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Antibodies, Antineutrophil Cytoplasmic↗
A new ultrasonic process for a renewal of aortic valve decalcification.
BACKGROUND: Aortic valve decalcification by ultrasound was given up. We evaluated a new ultrasound microhandpiece (Dissectron Penstyle) to rehabilitate this alternative treatment. METHODS: We used under magnifying lenses the ultrasound microhandpiece to decalcify 30 explanted aortic valves. In the cases with embedded calcifications the thin top of the probe could be introduced into the thickness of the leaflet preserving covering layers. RESULTS: The leaflets were totally decalcified and flexible, and surrounding structures were preserved as assessed by histological examination. CONCLUSION: This new approach of ultrasonic aortic valve decalcification gives good in vitro results which allow to consider a clinical evaluation of this procedure.
Aortic Valve↗
Specific inhibition of the mitochondrial permeability transition prevents lethal reperfusion injury.
The aim of the present study was to determine whether specific inhibition of mitochondrial permeability transition (MPT) by NIM811 at the time of reperfusion following acute myocardial infarction may protect the heart. MPT pore opening appears to be a pivotal event in cell death following acute myocardial infarction. Recently, MPT pore opening has been involved in ischemic preconditioning. In protocol 1, NZW rabbits underwent either no intervention (sham) or 10 min of ischemia followed by 5 min of reperfusion, preceded (preconditioned, PC) or not (control, C) by 5 min of ischemia and 5 min of reperfusion. Additional rabbits were treated by cyclosporin A (CsA) or its non-immunosuppressive and more specific derivative (NIM811) (10 mg kg(-1), IV bolus), either 10 min before ischemia or 1 min before reperfusion. Hearts were excised and mitochondria isolated for further assessment of Ca(2+)-induced MPT. In protocol 2, animals were randomly assigned into similar experimental groups and underwent 30 min of ischemia and 4 h of reperfusion. Infarct size was assessed by TTC staining, and apoptosis by TUNEL assay. The Ca2+ overload required to induce MPT pore opening was significantly higher in NIM811, CsA and PC groups than in controls. Both necrotic and apoptotic cardiomyocyte death were significantly reduced by NIM811, CsA and PC. In both protocols, administration of NIM811 at reperfusion provided full protection. These data indicate that specific inhibition of MPT pore opening at reperfusion following acute myocardial infarction provides a powerful antinecrotic and antiapoptotic protection.
Animals↗
Quantitative study of nerves of the human left atrium.
OBJECTIVES: To quantify and study the distribution of innervation of the left atrium and the pulmonary veins in humans. BACKGROUND: Damage to cardiac nerves has been hypothesized as the explanation for successful radiofrequency ablation of atrial fibrillation. METHODS: From January 2003 to September 2003, histologic and quantitative studies of innervation of the left atrium and the pulmonary veins was performed in 43 consecutive necropsied adult hearts (30 men and 3 women; mean age 45.5 +/- 12.4 years). The left atrium was sectioned in 1-cm slices from left to right, with the plane of section perpendicular to the long axis of the heart. Sections of the pulmonary veins at their ostia and sections 1 cm away of this structure also were obtained. Nerve fiber density was counted manually for each case and expressed as the mean number per slice. RESULTS: Numerous epicardial nerve fibers and ganglia having distinct patterns of distribution in the left atrium were found. Nerve density was significantly higher at the ostia of the four pulmonary veins than in their distal part (7.1 +/- 2.1 vs 5.2 +/- 1.3 for left upper pulmonary vein; 6.3 +/- 1.5 vs 5.2 +/- 1.7 for right upper pulmonary vein; 7.4 +/- 2 vs 5.9 +/- 2 for left lower pulmonary vein; 6.7 +/- 1.8 vs 3.9 +/- 1.3 for right lower pulmonary vein). The left superior vein was significantly more innervated than the right inferior vein (12.3 +/- 3 vs 10.6 +/- 1.4). Gradients of innervation were found from right to left (9.8 +/- 4.6 vs 18.5 +/- 6.6, P < .05) and from the front to the rear of the atrium (17.2 +/- 6.4 vs 20.7 +/- 6.5, P < .05). The same heterogeneous distribution was observed at the myocardial level but with thinner nerve fibers, making quantification difficult. Only very thin nerve fibers were present in the endocardium. CONCLUSIONS: The human left atrium exhibits several gradients of innervation at discrete sites. These findings may have clinical implications for radiofrequency ablation of atrial fibrillation.
Adolescent↗
[Thymic neuroendocrine tumors: report on 6 cases].
AIM: the aim of our study was to analyze a series of 6 thymic neuroendocrine tumors (TNET). METHODS: we report the clinical and pathological features of 6 TNET reclassified according to the last WHO classification (2004). RESULTS: there were 4 men and 2 women, (mean age of 61.3 years), presenting with local symptoms in 4 cases. The tumors were reclassified as 3 atypical carcinoids (AC), 2 small cell carcinomas (SCC) and 1 large cell neuroendocrine carcinoma (LCNEC). Cytokeratin, EMA and neuroendocrine markers were expressed in poorly-differentiated tumors. Two patients were lost of follow-up. Two patients with AC died of disease at 20 and 36 months. One patient with SCC died of disease at 2 years and the patient with the LCNEC died of disease in 3 months. CONCLUSION: TNET are poor prognosis tumors with a prognosis similar to thymic carcinomas. Adequate surgical resection is a strong prognosis factor.
Aged↗
Staphylococcus aureus Panton-Valentine leukocidin directly targets mitochondria and induces Bax-independent apoptosis of human neutrophils.
Panton-Valentine leukocidin (PVL) is a pore-forming toxin secreted by Staphylococcus aureus that has recently been associated with necrotizing pneumonia. In the present study, we report that in vitro, PVL induces polymorphonuclear cell death by necrosis or by apoptosis, depending on the PVL concentration. PVL-induced apoptosis was associated with a rapid disruption of mitochondrial homeostasis and activation of caspase-9 and caspase-3, suggesting that PVL-induced apoptosis is preferentially mediated by the mitochondrial pathway. Polymorphonuclear cell exposure to PVL leads to mitochondrial localization of the toxin, whereas Bax, 1 of the 2 essential proapoptotic members of the Bcl-2 family, was still localized in the cytosol. Addition of PVL to isolated mitochondria induced the release of the apoptogenic proteins cytochrome c and Smac/DIABLO. Therefore, we suggest that PVL, which belongs to the pore-forming toxin family, could act at the mitochondrion level by creating pores in the mitochondrial outer membrane. Furthermore, LukS-PV, 1 of the 2 components of PVL, was detected in lung sections of patients with necrotizing pneumonia together with DNA fragmentation, suggesting that PVL induces apoptosis in vivo and thereby is directly involved in the pathophysiology of necrotizing pneumonia.
Apoptosis↗
Cardiac valves in patients with Whipple endocarditis: microbiological, molecular, quantitative histologic, and immunohistochemical studies of 5 patients.
The pathological features of Whipple endocarditis, which is caused by Tropheryma whipplei, were histologically evaluated in cardiac valves from 5 patients. We used quantitative image analysis to compare the valvular fibrosis, calcifications, vegetations, inflammation, and vascularization due to Whipple endocarditis with those due to non-Whipple endocarditis and degenerative valves. We also studied the presence of T. whipplei in valves by immunohistochemical analysis, culture, and polymerase chain reaction (PCR). In histologic analysis, Whipple endocarditis was characterized by significant fibrosis, a lack of calcifications, slight inflammation and vascularization, and vegetations of intermediate size. Inflammatory infiltrates consisted mainly of foamy macrophages and lymphocytes. We found that the detection of T. whipplei in cardiac valves, by immunohistochemical analysis, was correlated with the detection of the bacterium by culture and PCR. We report, for the first time, the immunodetection of T. whipplei in a surgically removed arterial embolus. Pathological and immunohistologic analyses may contribute to the diagnosis of Whipple endocarditis.
Adult↗
Preconditioning delays Ca2+-induced mitochondrial permeability transition.
OBJECTIVE: We investigated whether ischemic preconditioning (PC) may modify mitochondrial permeability transition (MPT) pore opening. METHODS: In protocol 1, New Zealand White rabbits underwent either no intervention (sham group) or 10 min of ischemia followed by 5 min of reperfusion, preceded (PC) or not (C; control) by one episode of 5 min of ischemia and 5 min of reperfusion. Rabbits were pretreated by either saline or the MPT pore inhibitor cyclosporin A (CsA), or its non-immunosuppressive derivative Cs29 (10 mg/kg, IV bolus). Hearts were harvested and mitochondria isolated for further assessment of Ca(2+)-induced MPT using a Ca(2+)-sensitive micro-electrode. In protocol 2, C and PC hearts underwent 30 min of ischemia and 4 h of reperfusion. They were pretreated either by saline, CsA or Cs29, as in protocol 1. Infarct size was assessed by triphenyltetrazolium, and apoptosis by TUNEL staining. RESULTS: In protocol 1, the Ca(2+) overload required to induce MPT pore opening was significantly higher in PC than in C hearts. CsA and Cs29 significantly increased the Ca(2+) overload required for MPT pore opening. In protocol 2, mean infarct size averaged 25% of the risk region in CsA/Cs29 treated hearts versus 15% in PC and 55% in controls (P<0.05 vs. C, P=ns vs. PC). Cardiomyocyte apoptosis was significantly reduced by PC and cyclosporin treatment with a mean apoptotic index of less than 2% in either group versus more than 11% in controls. CONCLUSION: This suggests that delayed opening of MPT pore may play a major role in ischemic PC.
Animals↗
[Alveolar capillary dysplasia with misalignment of pulmonary vessels].
Alveolar capillary dysplasia (ACD), with or without pulmonary vein misalignment is a uniformly fatal cause of persistent pulmonary hypertension and respiratory failure, first described in 1981. We report the case of ACD in a full term newborn with post mortem pathologic confirmation. Sixty five cases have been reported in the literature, most are sporadic, but a few cases of familial ACD suggest an autosomal recessive inheritance. In 55% of the reported cases of ACD other cardiovascular, digestive or urogenital anomalies were associated. ACD is presumed to be a primary capillary disorder. It affects full-term neonates who exhibit respiratory distress during the early post natal period due to pulmonary hypertension and die within 3 weeks of birth. Histologic findings include a decrease in the number of alveolar capillaries, which are placed centrally within the intralobular septa, ectatic veins accompany the bronchovascular bundles instead of being in their normal position in the interlobular septum, and muscularized pulmonary arteries extend to the distal level. Prognosis is very poor, intravenous prostacyclin with inhaled nitric oxide have been reported in the cases with the best survival.
Capillaries↗
Ceramide in the antiapoptotic effect of ischemic preconditioning.
Although the mechanism by which ischemic preconditioning (PC) inhibits myocardial apoptosis during ischemia-reperfusion is unclear, evidence indicates a role for the secondary messenger ceramide. We investigated in vivo whether PC may affect ceramide and sn-1,2-diacylglycerol (DAG) production, and attenuate apoptosis during ischemia. Rabbits underwent 30 min of ischemia, followed by 4 h of reperfusion. Before this, they received either no intervention (control group) or one episode of 5 min of ischemia, followed by 5 min of reperfusion (PC group), or an intravenous administration of the sphingomyelinase inhibitor D609. Myocardial content of ceramide and DAG was measured using the DAG kinase assay at different time points of the experiment. Apoptosis was detected and quantified by a sandwich enzyme immunoassay. Both AR and infarct size were measured using blue dye injection and triphenyltetrazolium chloride staining. Control hearts exhibited a peak of ceramide production at 5 min of the prolonged ischemia, with a mean value averaging 64 +/- 5 ng/mg tissue (P < 0.05 vs. 48 +/- 4 ng/mg at baseline). In contrast, ischemic PC and D609 prevented ceramide increase during the prolonged ischemia. Myocardial DAG content was increased only in PC hearts at 30 min of ischemia. Preconditioned and D609 groups developed less apoptosis, as well as a limited infarct size, compared with the control group. These results suggest that the antiapoptotic effect of PC may be due to a reduced ceramide production during sustained ischemia in the rabbit heart.
Animals↗
Molecular diagnosis of infective endocarditis by PCR amplification and direct sequencing of DNA from valve tissue.
We used broad-range eubacterial PCR amplification followed by direct sequencing to identify microbial pathogens in heart valve material from 29 patients with histologically confirmed infective endocarditis and 23 patients free of infective endocarditis. Microorganisms cultured by conventional techniques matched those identified by PCR in 21 cases. PCR alone identified the causative agent in three cases (Streptococcus bovis, Staphylococcus cohnii, and Coxiella burnetii), allowing better patient management. PCR corrected the initial bacteriological diagnosis in three cases (Streptococcus bovis, Streptococcus mutans, and Bartonella henselae). Among the 29 cases of histologically confirmed infective endocarditis, PCR findings were positive in 27 cases and were consistent with the bacterial morphology seen at Gram staining (26 cases) or with the results obtained by immunohistologic analysis with an anti-C. burnetii monoclonal antibody (one case). In two other cases of histologically confirmed infective endocarditis, PCR remained negative in a blood culture-negative case for which no bacteria were seen at histological analysis and in one case with visualization of cocci and blood cultures positive for Enterococcus faecalis. Ten clinical diagnoses of possible infective endocarditis were ruled out by histopathological analysis of the valves and subsequently by PCR. PCR was negative in 13 of the 14 patients in whom infective endocarditis was rejected on clinical grounds; the other patient was found to have Coxiella burnetii infective endocarditis on the basis of PCR and histopathological analysis and was subsequently included in the group of 29 definite cases. In total, PCR contributed to the diagnosis and management of infective endocarditis in 6 of 29 (20%) cases.
DNA, Bacterial↗
Primary cardiac lymphoma in immunocompetent patients: a report of three cases and review of the literature.
Primary cardiac lymphoma is an extranodal non-Hodgkin's lymphoma exclusively located in the heart and/or pericardium, extremely rare in immunocompetent patients, and more frequent in immunodepressed patients. We present 3 retrospectives cases of primary cardiac lymphoma in immunocompetent patients and review 35 cases reported in the literature. Two patients were adults and one was a child. Primary cardiac lymphoma presented with constitutional symptoms in two cases and superior vena caval syndrome in one case. Diagnosis of a tumor mass was made in all cases by transthoracic echocardiography. Primary cardiac lymphoma arose in the heart right chambers in two cases. Histological diagnoses, obtained after thoracotomy, were diffuse large B-cell lymphoma in two cases, and Burkitt's lymphoma in one case. All three cases received chemotherapy, combined with radiotherapy in one patient. Of our patients, 2 are alive and asymptomatic 12 months and 33 months after diagnosis. In conclusion, diagnosis of primary cardiac lymphoma is difficult due to non-specific clinical manifestations and should be considered in patients with a cardiac mass sometimes with pericardial effusion. It is confirmed using transthoracic echocardiography and magnetic resonance imaging and certified using cytology or open biopsy. The only effective treatment is chemotherapy, but prognosis remains poor.
Aged↗
Primary sarcomas of the lung: a clinicopathologic study of 12 cases.
BACKGROUND: Chest physicians have a limited experience of primary pulmonary sarcomas, which represent a particular entity among rare intrathoracic neoplasms. DESIGN: Retrospective review of medical records. PURPOSE: To study patients with primary sarcomas of the lung diagnosed in our pathology department in order to define their clinical characteristics, treatment, and prognosis. PATIENTS: The study group consisted of 12 patients, with a mean age of 53 years. RESULTS: The main symptoms were chest pain, and cough. Imaging findings consisted of: eight single peripheral opacities, three single parahilar opacities, and one lobar actelectasis. The histologic diagnoses confirmed in all cases by detailed immunohistochemical study were leiomyosarcoma (7), monophasic synovial sarcoma (2), one case each of malignant peripheral nerve sheath tumor (MPNST), epithelioid sarcoma, and malignant fibrous histiocytoma. Thoracic surgery done in nine cases consisted of six lobectomies with further parietal resection in two cases, and three pneumonectomies. Four patients received chemotherapy and two patients had radiation therapy postoperatively. Follow up available on 12 patients ranged from 3 to 144 (mean 42) months. Long term survival up to 3 years was observed in five patients. Median overall survival was 48 months. Overall 5-year survival rate was 38%. CONCLUSIONS: Primary sarcomas of the lung are a rare and aggressive malignancy. Treatment and prognosis do not differ from other soft tissue sarcomas.
Adolescent↗
Correlation of the WHO schema for the classification of thymic epithelial neoplasms with prognosis: a retrospective study of 90 tumors.
A series of 90 thymic epithelial tumors were reviewed and classified by histopathologic characteristics into the three major categories (A, B, and C) recognized by the WHO schema. Each tumor type was correlated with patient characteristics and clinical data (age, sex, presence of myasthenia gravis, tumor size and invasiveness, and completeness of resection), and with outcome (survival, recurrence, and metastasis). All tumors were categorized by the WHO schema. Myasthenia gravis was present in 32 patients, mostly young and with type B thymic epithelial tumors. Tumors were invasive in 56% of cases, but resection was total in 67% of patients and only partial in the rest. Five factors were shown by univariate analysis to be associated with a favorable prognosis: presence of myasthenia gravis (p = 0.0389), younger age (p = 0.0022), completeness of resection (p = 0.0001), noninvasiveness (p = 0.0138), and tumor type A or B, as opposed to type C (p = 0.0001). Prognosis for types A and B was not significantly different, suggesting that the subtypes of types A and B thymic epithelial tumors should be regarded as a morphologic continuum rather than as distinct histologic variants.
Adolescent↗
Malignant pleural mesothelioma with osteoblastic heterologous elements: CT and MR imaging findings.
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Biopsy↗