Diffusion chamber system for testing of collagen-based cell migration barriers for separation of ligament enthesis zones in tissue-engineered ACL constructs.

A temporary barrier separating scaffold zones seeded with different cell types prevents faster growing cells from overgrowing co-cultured cells within the same construct. This barrier should allow sufficient nutrient diffusion through the scaffold. The aim of this study was to test the effect of two variants of collagen-based barriers on macromolecule diffusion, viability, and the spreading efficiency of primary ligament cells on embroidered scaffolds. Two collagen barriers, a thread consisting of a twisted film tape and a sponge, were integrated into embroidered poly(lactic-co-caprolactone) and polypropylene scaffolds, which had the dimension of lapine anterior cruciate ligaments (ACL). A diffusion chamber system was designed and established to monitor nutrient diffusion using fluorescein isothiocyanate-labeled dextran of different molecular weights (20, 40, 150, 500 kDa). Vitality of primary lapine ACL cells was tested at days 7 and 14 after seeding using fluorescein diacetate and ethidium bromide staining. Cell spreading on the scaffold surface was measured using histomorphometry. Nuclei staining of the cross-sectioned scaffolds revealed the penetration of ligament cells through both barrier types. The diffusion chamber was suitable to characterize the diffusivity of dextran molecules through embroidered scaffolds with or without integrated collagen barriers. The diffusion coefficients were generally significantly lower in scaffolds with barriers compared to those without barriers. No significant differences between diffusion coefficients of both barrier types were detected. Both barriers were cyto-compatible and prevented most of the ACL cells from crossing the barrier, whereby the collagen thread was easier to handle and allowed a higher rate of cell spreading.

In vitro characterization of self-assembled anterior cruciate ligament cell spheroids for ligament tissue engineering.

Tissue engineering of an anterior cruciate ligament (ACL) implant with functional enthesis requires site-directed seeding of different cell types on the same scaffold. Therefore, we studied the suitability of self-assembled three-dimensional spheroids generated by lapine ACL ligament fibroblasts for directed scaffold colonization. The spheroids were characterized in vitro during 14 days in static and 7 days in dynamic culture. Size maintenance of self-assembled spheroids, the vitality, the morphology and the expression pattern of the cells were monitored. Additionally, we analyzed the total sulfated glycosaminoglycan, collagen contents and the expression of the ligament components type I collagen, decorin and tenascin C on protein and for COL1A1, DCN and TNMD on gene level in the spheroids. Subsequently, the cell colonization of polylactide-co-caprolactone [P(LA-CL)] and polydioxanone (PDS) polymer scaffolds was assessed in response to a directed, spheroid-based seeding technique. ACL cells were able to self-assemble spheroids and survive over 14 days. The spheroids decreased in size but not in cellularity depending on the culture time and maintained or even increased their differentiation state. The area of P[LA-CL] scaffolds, colonized after 14 days by the cells of one spheroid, was in average 4.57 ± 2.3 mm(2). Scaffolds consisting of the polymer P[LA-CL] were more suitable for colonization by spheroids than PDS embroideries. We conclude that ACL cell spheroids are suitable as site-directed seeding strategy for scaffolds in ACL tissue engineering approaches and recommend the use of freshly assembled spheroids for scaffold colonization, due to their balanced proliferation and differentiation.

Embroidered polymer-collagen hybrid scaffold variants for ligament tissue engineering.

Embroidery techniques and patterns used for scaffold production allow the adaption of biomechanical scaffold properties. The integration of collagen into embroidered polylactide-co-caprolactone [P(LA-CL)] and polydioxanone (PDS) scaffolds could stimulate neo-tissue formation by anterior cruciate ligament (ACL) cells. Therefore, the aim of this study was to test embroidered P(LA-CL) and PDS scaffolds as hybrid scaffolds in combination with collagen hydrogel, sponge or foam for ligament tissue engineering. ACL cells were cultured on embroidered P(LA-CL) and PDS scaffolds without or with collagen supplementation. Cell adherence, vitality, morphology and ECM synthesis were analyzed. Irrespective of thread size, ACL cells seeded on P(LA-CL) scaffolds without collagen adhered and spread over the threads, whereas the cells formed clusters on PDS and larger areas remained cell-free. Using the collagen hydrogel, the scaffold colonization was limited by the gel instability. The collagen sponge layers integrated into the scaffolds were hardly penetrated by the cells. Collagen foams increased scaffold colonization in P(LA-CL) but did not facilitate direct cell-thread contacts in the PDS scaffolds. The results suggest embroidered P(LA-CL) scaffolds as a more promising basis for tissue engineering an ACL substitute than PDS due to superior cell attachment. Supplementation with a collagen foam presents a promising functionalization strategy.

[The French mesothelioma network from 1998 to 2013]. / Mésothéliome: les dispositifs en place en France « le réseau mésothéliome ¼ 1998-2013.

Mesothelioma is a rare disease less than 0.3% of cancers in France, very aggressive and resistant to the majority of conventional therapies. Asbestos exposure is nearly the only recognized cause of mesothelioma in men observed in 80% of case. In 1990, the projections based on mortality predicted a raise of incidence in mesothelioma for the next three decades. Nowadays, the diagnosis of this cancer is based on pathology, but the histological presentation frequently heterogeneous, is responsible for numerous pitfalls and major problems of early detection toward effective therapy. Facing such a diagnostic, epidemiological and medico-legal context, a national and international multidisciplinary network has been progressively set up in order to answer to epidemiological survey, translational or academic research questions. Moreover, in response to the action of the French Cancer Program (action 23.1) a network of pathologists was organized for expert pathological second opinion using a standardized procedure of certification for mesothelioma diagnosis. We describe the network organization and show the results during this last 15years period of time from 1998-2013. These results show the major impact on patient's management, and confirm the interest of this second opinion to provide accuracy of epidemiological data, quality of medico-legal acknowledgement and accuracy of clinical diagnostic for the benefit of patients. We also show the impact of these collaborative efforts for creating a high quality clinicobiological, epidemiological and therapeutic data collection for improvement of the knowledge of this dramatic disease.

Transient accumulation of gamma-butyrolactone during degradation of bis(4-chloro-n-butyl) ether by diethylether-grown Rhodococcus sp. strain DTB.

Rhodococcus sp. strain DTB (DSM 44534) grows aerobically on diethylether as sole source of carbon and energy. Dense cell suspension experiments showed that the induced ether-cleaving enzyme system attacks a broad range of ethers like tetrahydrofuran, phenetole and chlorinated alkylethers including Calpha-substituted alkylethers. Identification of metabolites revealed that degradation of the ethers started by an initial attack of the ether bond. Diethylether-grown cells degraded bis(4-chloro-n-butyl) ether via an initial ether scission followed by the transient accumulation of gamma-butyrolactone as intermediate at nearly stoichiometric concentrations.

Exsanguinating hemoptysis revealing the absence of left pulmonary artery in an adult.

Isolated absence of a pulmonary artery is an exceptional cause of massive hemoptysis. We report a 35-year-old woman with agenesis of the left pulmonary artery who presented with exsanguinating hemoptysis that prompted angiography with the aim to embolize the bleeding vessels selectively. The procedure could not be completed because of the presence of an anterior spinal artery branching from the aberrant systemic-to-pulmonary circulation. The patient successfully underwent an emergent pneumonectomy.

Osteosarcomas of flat bones in adolescents and adults.

BACKGROUND: Osteosarcomas typically are long bone tumors and rarely affect the flat bones of the axial or appendicular skeleton. METHODS: The authors examined cases of high grade osteosarcoma of flat bones diagnosed at La Timone Adults University Hospital during a 16-year period. RESULTS: Sixteen patients with flat bone osteosarcomas were treated between 1980-1997. The median age of the patients was 25 years, with a male-to-female ratio of 14:2. Common presenting symptoms were swelling, pain, or both. Primary therapy included resection (n = 11 patients: alone in 8 patients and with radiation therapy in 3 patients), radiation therapy (n = 2 patients), or no local treatment (n = 3 patients). All patients received polychemotherapy, 7 preoperatively and postoperatively and 9 in the adjuvant setting. The overall 5-year survival rate was 47.7%; the overall median survival was 39 months (range, 4-211 months). The adequate local control rate was 68.7%. The local recurrence rate in patients who benefited from local treatment was 54%. Significant adverse prognostic factors on survival included the presence of synchronous metastases (three patients), metastases at any time during the course of the disease (eight patients), and inadequate local control (five patients). The overriding predictor of survival appeared to be the presence of metastases. Local recurrence appeared to have no influence on survival. No patient with metastases was alive at 3 years, whereas patients without recurrence or with local recurrence alone had a 5-year survival rate of 100%. Because the majority of patients with flat bone osteosarcomas ultimately die of metastatic disease, intensive systematic polychemotherapy should be an important component of treating these tumors. CONCLUSIONS: Based on the very encouraging results observed in the treatment of long bone osteosarcomas, the therapy for flat bone osteosarcomas should combine radical surgery with preoperative and postoperative adjuvant chemotherapy.

Diagnostic accuracy of protected catheter sampling in ventilator-associated bacterial pneumonia.

The aim of this study was to assess the accuracy of protected telescoping catheter performed using: 1) protected distal aspiration, or 2) protected mini-bronchoalveolar lavage for the diagnosis of ventilator-associated bacterial pneumonia. Twenty-seven patients who died after receiving mechanical ventilation for at least 72 h were included in a comparative prospective post-mortem study. The two microbiological sampling procedures were performed immediately after death. Surgical pneumonectomies and biopsies were performed within 30 min of death at the bedside for histological examination. The results of the two techniques were compared with histological post-mortem lung examination or biopsies. Histological examination of the parenchyma showed signs of pneumonia in 14 cases. Lung tissue culture was positive in nine of these 14 cases. When ventilator-associated bacterial pneumonia was defined by the association of histological signs and positive lung tissue culture the sensitivity was 78% for both sampling techniques, specificity was 86% for mini-bronchoalveolar lavage and 100% for protected distal aspiration (at a threshold of 1 x 10(3) cfu x mL(-1)). Both techniques protected the distal aspiration and mini-bronchoalveolar lavage, and provided good specificity with an acceptable sensitivity for the diagnosis of ventilator-associated bacterial pneumonia.

[Bronchial mucoepidermoid carcinoma: apropos of 3 cases]. / Carcinome muco-épidermoïde bronchique: à propos de 3 observations.

We report three cases of bronchial mucoepidermoid carcinoma (BMEC) of low-grade malignancy with a relafase-free follow up. BMEC are rare tumors. The microscopic findings distinguish low-grade tumors which occur in children and young adults and high-grade tumors concerning older patients; this grading is based on the study of the epidermoid component. If possible, conservative therapy is appropriate in low-grade tumors. The prognosis of high-grade tumors is poor.

Aggressive form of pleural epithelioid haemangioendothelioma: complete response after chemotherapy.

Epithelioid haemangioendotheliomas are rare tumours of endothelial origin. They can develop in any tissue but occur principally in the lung and liver. Their usual course is a slow progression, so that they can be treated by surgery. In aggressive forms, no treatment has proved efficient to date. This study, describes a case of bilateral pleural epithelioid haemangioendothelioma that extended to the peritoneum. The histological diagnosis was confirmed by both conventional examination and immunohistochemistry. After six courses of carboplatine plus etoposide, a complete response was obtained. The complete remission is still lasting at 18 months after the diagnosis and the patient is healthy.

[Mucoepidermoid bronchial tumor with an unusual radiologic presentation]. / Une tumeur bronchique muco-épidermoïde à présentation radiologique originale.

We report a case of low-grade malignant mucoepidermoid bronchial tumor in a 21-year-old woman who presented with hemoptysis. There was a striking radiological presentation with a unilateral clear radiograph. Lung scintigraphy demonstrated perturbed ventilation and perfusion of the left lung. Pulmonary angiography only showed diminished peripheral vascularization. The main vessels were clear. These anomalies fit the radiological category of air trapping accompanied by probably hypoxic pulmonary vasoconstriction. Mucoepidermoid tumors account for only 0.5-1% of all primary lung tumors. They are found in adults as well as in children. There are two clear-cut histological forms with very different prognosis. The tumors of high-grade malignancy are considered as undifferentiated carcinomas and should be treated as such. The prognosis is much better for tumors of low-grade malignancy and current treatment is surgical in the absence of recurrence after isolated endoscopic treatment.

Pulmonary arteriovenous malformations: lung transplantation as a therapeutic option.

Multiple pulmonary arteriovenous malformations (PAVM) constitute an uncommon cause of respiratory disability. They may lead to severe hypoxaemia via right-to-left shunts and are sources of substantial mortality and morbidity. Conservative surgical resection has been proposed as the treatment of choice. More recently, percutaneous balloon or coil embolization of the feeding vessels offered an efficacious and safe alternative therapy for patients whose fistulas are too numerous to excise. This study reports an unusual case of respiratory disability in a patient with multiple and microscopic pulmonary arteriovenous malformations who failed to respond to embolotherapy and who received a double lung transplantation with good initial outcome.

Open-lung biopsy in patients with acute respiratory distress syndrome.

BACKGROUND: It has been suggested that fibrosis present during the fibroproliferative phase of acute respiratory distress syndrome (ARDS) can be treated by corticosteroids. However, neither clinical nor microbiologic criteria permit differentiation of this fibroproliferative phase from a nosocomial pneumonia. The aim of this observational case series was to evaluate the safety and utility of open-lung biopsy (OLB) performed in patients receiving ventilatory support who had persistent ARDS despite negative bacterial cultures. METHODS: During a 4-yr period, 37 OLBs were performed in 36 of 197 patients receiving ventilatory support who had ARDS. The severity of ARDS was assessed by a lung injury score of 3.1 +/- 0.4 (mean +/- SD) and a median ratio of the partial pressure of oxygen (PaO2) to the fraction of inspired oxygen (FiO2) of 118 mmHg. Histologic examination; bacterial, fungal, and acid-fast staining; and cultures of the tissue sample were performed. RESULTS: Fibrosis was present in only 41% of the lung specimens obtained by OLB. Only six patients received corticosteroids (17%). In 9 of the 15 patients with fibrosis, cytomegalovirus pneumonia precluded the use of corticosteroids. Histologic cytomegalovirus pneumonia was diagnosed in 18 cases. Histologic bacterial or mycobacterial pneumonia was diagnosed in five cases. No significant change in arterial blood gases was noted as linked to the biopsy procedure except an increase of the PaO2/FiO2 ratio. One pneumothorax was diagnosed on a chest roentgenogram 12 h after OLB. Only one patient required blood transfusion during the 48-h period after OLB (for an hemothorax). Five patients had moderate air leaks from operative chest tubes for 2-10 days. CONCLUSIONS: Open lung biopsy appeared to be a useful and acceptably safe diagnostic technique in patients with ARDS. It permitted the diagnosis of unexpected cytomegalovirus pneumonia.

[Ecoendoscopy in the assessment of esophageal neoplasms]. / Ecoendoscopía en la evaluación del cáncer del esófago.

OBJECTIVE: To asses the diagnostic accuracy of endoscopic ultrasonography (EUS) for the local and regional staging of esophageal cancer, and its possible alteration resulting from the performance of preoperative chemoradiation. METHODS: Prospective study of 85 consecutive patients with esophageal cancer evaluated by EUS and operated between January 1992 and December 1995. 28 of these patients had received previous induction therapy. In all cases, EUS examination was performed by the same physician not informed about the results of previous morphological explorations. Histopathological analysis of all specimens was performed by the same pathologist, not informed about the results of the EUS. Data were collected by another independent observer. RESULTS: EUS examination resulted in incomplete staging in 8 patients (9.5%) with severe stenosis precluding endoscope passage. The accuracy, specificity and sensibility of EUS in detecting the depth of esophageal involvement (T0-2 vs T3-4) were 82.3%, 78% and 86% respectively, and 72%, 70% and 73% respectively for the lymph node metastasis. The overall accuracy of EUS in identifying the preoperative stage was 67% with a clear-cut alteration when patients had received induction therapy (61% vs 72%). On the other hand, 7(64%) of the 11 patients thought to have a complete response at endosonography had no residual tumor. CONCLUSION: EUS provides precise information for the preoperative identification of locally advanced esophageal tumor, even after induction therapy. The latter alters the diagnostic accuracy of EUS, although complete responders could be identified in two-thirds os cases.

Ecoendoscopia en la evaluacion del cancer del esofago / Ecoendoscopy in the evaluation of the esophageal neoplasms

Objectivo: Evaluar la presición diagnóstica de la ecoendoscopía para la apreciación de la extensión loco-regional del cáncer del esófago, y su eventual modificación ante un tratamiento neoadyuvante con quimio y radioterapia. Método: Estudio prospectivo sobre 85 pacientes operados por un cáncer del esófago entre enero de 1992 y diciembre de 1995, todos evaluados previamente con ecoendoscopía. Del total de 85 pacientes, 21 recibieron un tratamiento neoadyuvante con quimio y radioterapia. Todos los estudios endoscópicos fueron realizados por el mismo operador, que ignoraba el resultado de otros estudios morfológicos. Todos los exámenes anatomapotológicos de la pieza de resección fueron realizados por el mismo operador que desconocía el resultado de la ecoendoscopía preoperatoria. La confrontación de los datos de la anatomía patológica y de la ecoendoscopía fue realizado por un tercer observador independiente. Resultados: La ecoendoscopía fue incompleta por una estenosis esofágica en 8 casos (9,5 por ciento). La evaluación de la invasión de la pared esofágica tuvo una exactitud del 82,3 por ciento, uma sensibilidad del 78 por ciento y una espeficificidad del 86 por ciento. La evaluación de la extensión ganglionar tuvo una exactitud del 72 por ciento, una sensibilidad del 70 por ciento y una especificidad del 73 por ciento. La evaluación del estadío fue concordante en el 67 por ciento de los casos con un rendimiento totalmente alterado después de realizar tratamiento neoadyuvante con radio-quimioterapia (61 por ciento contra 72 por ciento). Paralelamente, 7 (64 por ciento) de los 11 enfermos que tuvieron una correlación ecoendoscópica perfecta habían tendio una respuesta completa con el tratamiento neoadyuvante. Conclusión: La ecoendoscopías es un método preciso para la evaluación preoperatoria de los tumores del esófago localmente avanzados, asi mismo después de un tratamiento deoadyuvante. Esta última alternativa modifica negativamente el rendimento ddiagnóstico pero de todas formas permite dos veces sobre tres realizar una correlación perfecta en aquellos enfermos que tuvieron una respuesta completa al tratamiento neoadyuvante. (AU)

Ecoendoscopia en la evaluacion del cancer del esofago / Ecoendoscopy in the evaluation of the esophageal neoplasms

Objectivo: Evaluar la presición diagnóstica de la ecoendoscopía para la apreciación de la extensión loco-regional del cáncer del esófago, y su eventual modificación ante un tratamiento neoadyuvante con quimio y radioterapia. Método: Estudio prospectivo sobre 85 pacientes operados por un cáncer del esófago entre enero de 1992 y diciembre de 1995, todos evaluados previamente con ecoendoscopía. Del total de 85 pacientes, 21 recibieron un tratamiento neoadyuvante con quimio y radioterapia. Todos los estudios endoscópicos fueron realizados por el mismo operador, que ignoraba el resultado de otros estudios morfológicos. Todos los exámenes anatomapotológicos de la pieza de resección fueron realizados por el mismo operador que desconocía el resultado de la ecoendoscopía preoperatoria. La confrontación de los datos de la anatomía patológica y de la ecoendoscopía fue realizado por un tercer observador independiente. Resultados: La ecoendoscopía fue incompleta por una estenosis esofágica en 8 casos (9,5 por ciento). La evaluación de la invasión de la pared esofágica tuvo una exactitud del 82,3 por ciento, uma sensibilidad del 78 por ciento y una espeficificidad del 86 por ciento. La evaluación de la extensión ganglionar tuvo una exactitud del 72 por ciento, una sensibilidad del 70 por ciento y una especificidad del 73 por ciento. La evaluación del estadío fue concordante en el 67 por ciento de los casos con un rendimiento totalmente alterado después de realizar tratamiento neoadyuvante con radio-quimioterapia (61 por ciento contra 72 por ciento). Paralelamente, 7 (64 por ciento) de los 11 enfermos que tuvieron una correlación ecoendoscópica perfecta habían tendio una respuesta completa con el tratamiento neoadyuvante. Conclusión: La ecoendoscopías es un método preciso para la evaluación preoperatoria de los tumores del esófago localmente avanzados, asi mismo después de un tratamiento deoadyuvante. Esta última alternativa modifica negativamente el rendimento ddiagnóstico pero de todas formas permite dos veces sobre tres realizar una correlación perfecta en aquellos enfermos que tuvieron una respuesta completa al tratamiento neoadyuvante.

Diagnosis of ventilator-associated pneumonia: an evaluation of direct examination and presence of intracellular organisms.

BACKGROUND: Ventilator-associated pneumonia (VAP) requires early diagnosis and adequate antibiotic therapy. The aim of this prospective postmortem study was to assess the accuracy of direct examination and quantification of intracellular organisms (ICO) for the diagnosis of VAP. METHODS: Total and differential cell counts were performed on fluids recovered using nonbronchoscopic sampling techniques (blind bronchial sampling [BBS], mini-bronchoalveolar lavage [mini-BAL]) and from bronchoalveolar lavage (BAL) performed during fiberscopy. These 3 sampling techniques were done within 15 min of death without discontinuing mechanical ventilation. Quantification of ICO was performed on each sample recovered from the various sampling procedures. Gram reaction and morphology of bacteria were evaluated on Gram smears. RESULTS: The results of each technique were compared with histology and culture of lung tissue specimens obtained by surgical pneumonectomies in 28 patients who died after at least 72 h of mechanical ventilation. Histology was positive in 13 patients and negative in 15 patients. When only VAP with positive lung culture was considered (histologic signs of bronchopneumonia plus positive lung tissue culture), the sensitivity of Gram staining on BAL, mini-BAL, and BBS was 56%, 44%, and 56%, respectively. If all samples were considered, the sensitivity and the specificity of the determination of the percentage of ICO were low (less than 70%) whatever the sampling technique. CONCLUSIONS: For initial therapeutic guidance, direct examination and presence of ICO do not contribute for establishing the diagnosis of VAP, essentially because of a lack of sensitivity. However, when positive, Gram staining can obviously guide initial antibiotherapy.

[Severe bronchial stenosis with upstream bronchiectasis in an arc welder: causal relation or epiphenomenon?]. / Sténose bronchique serrée avec bronchectasies d'amont chez un soudeur à l'arc: relation causale ou épiphénomène?

This case concerns an arc welder who presented suppurative bronchiectasis and episodes of purulent left side pleurisy in relation to cystic bronchiectasis of the left lower lobe and a very severe stenosis at the origin of the main left bronchus. The medicolegal problem was to assess the causal relationship between these lesions and occupational exposure. They do not come under the heading of table 44 of the General List and we made this the aim of discretionary award in front of a regional committee of compensation for occupational disease.