Strain and Magnetic Field Induced Spin-Structure Transitions in Multiferroic BiFeO3.

The magnetic-field-dependent spin ordering of strained BiFeO3 films is determined using nuclear resonant scattering and Raman spectroscopy. The critical field required to destroy the cycloidal modulation of the Fe spins is found to be significantly lower than in the bulk, with appealing implications for field-controlled spintronic and magnonic devices.

Driving Spin Excitations by Hydrostatic Pressure in BiFeO(3).

Optical spectroscopy has been combined with computational and theoretical techniques to show how the spin dynamics in the model multiferroic BiFeO(3) responds to the application of hydrostatic pressure and its corresponding series of structural phase transitions from R3c to the Pnma phases. As pressure increases, multiple spin excitations associated with noncollinear cycloidal magnetism collapse into two excitations, which show jump discontinuities at some of the ensuing crystal phase transitions. The effective Hamiltonian approach provides information on the electrical polarization and structural changes of the oxygen octahedra through the successive structural phases. The extracted parameters are then used in a Ginzburg-Landau model to reproduce the evolution with pressure of the spin wave excitations observed at low energy, and we demonstrate that the structural phases and the magnetic anisotropy drive and control the spin excitations.

Crafting the magnonic and spintronic response of BiFeO3 films by epitaxial strain.

Multiferroics are compounds that show ferroelectricity and magnetism. BiFeO3, by far the most studied, has outstanding ferroelectric properties, a cycloidal magnetic order in the bulk, and many unexpected virtues such as conductive domain walls or a low bandgap of interest for photovoltaics. Although this flurry of properties makes BiFeO3 a paradigmatic multifunctional material, most are related to its ferroelectric character, and its other ferroic property--antiferromagnetism--has not been investigated extensively, especially in thin films. Here we bring insight into the rich spin physics of BiFeO3 in a detailed study of the static and dynamic magnetic response of strain-engineered films. Using Mössbauer and Raman spectroscopies combined with Landau-Ginzburg theory and effective Hamiltonian calculations, we show that the bulk-like cycloidal spin modulation that exists at low compressive strain is driven towards pseudo-collinear antiferromagnetism at high strain, both tensile and compressive. For moderate tensile strain we also predict and observe indications of a new cycloid. Accordingly, we find that the magnonic response is entirely modified, with low-energy magnon modes being suppressed as strain increases. Finally, we reveal that strain progressively drives the average spin angle from in-plane to out-of-plane, a property we use to tune the exchange bias and giant-magnetoresistive response of spin valves.

[Traumatic aortic regurgitation: diagnostic, management and treatment]. / Rupture traumatique de la valve aortique. Diagnostic, prise en charge et traitement.

Traumatic aortic valve regurgitation is a rare complication of non-penetrating thoracic trauma. The most frequent lesion is the isolated injury of the non-coronary cusp. Actually, the transoesophageal echocardiography is the procedure of choice to confirm the diagnosis and to reveal the associated cardiovascular lesions. Surgical management with early operation is the best policy, however this surgery can be delayed for treatment of other life-threatening injuries. Up today, aortic valve replacement (AVR) was recommended to repair traumatic aortic valve regurgitation; nevertheless, in the recent international literature, the number of cases reports with conservative surgery (CS) is increasing: 10 AVR (group I) and 10 CS (group II). Analysis of the post-operative and long term periods shows good results: it confirms the excellent clinical evolution in the group I (mean time of follow-up: 18.2 +/- 16.3 months), and reveals satisfactory results in the group II for patients with isolated lesion (mean time of follow-up: 29.1 +/- 30.7 months). In conclusion, each time the traumatic aortic regurgitation is due to an isolated lesion, the conservative surgery should be performed in order to avoid aortic valve replacement and its potential complications especially in young patients with healthy valves. However, the aortic valve replacement is the safest technique for complex or multiple injuries of the aortic valve.

Fracture embolization of a Tekna mitral prosthesis: case report.

The modified Duromedics-Tekna bileaflet pyrolitic carbon mechanical prosthesis was reintroduced by Baxter in 1990. This report details the first case of sudden leaflet fracture of a Tekna mitral valve five years after implantation, which was managed successfully by replacement with a St. Jude Medical mechanical prosthesis. The fracture had occurred transversely, with the fragments embolizing to the terminal aortic bifurcation and the left common femoral artery. These were localized by computed tomography and removed two days after valve replacement.

Patient information about radiation therapy: a survey in Europe.

BACKGROUND AND PURPOSE: We performed a survey to evaluate the present status and means of information given to patients treated by radiotherapy. A short questionnaire was sent, with the help of ESTRO, to 746 European heads of department with a request to send specific documents used for informing the patient. Within 2 months (March and April 1996) we received 290 answers (39%) and 97 centres sent documents. MATERIALS AND METHODS: Analysis of the questionnaire and the documents was performed quantitatively with usual statistical methods and qualitatively with a socio-anthropological method of content analysis. RESULTS: Analysis of the questionnaire shows the major role of the radiation oncologist in giving information and writing documents. The 298 different samples sent from 97 centres represent a wide panel with a booklet of general information (59 booklets/57 centres), practical advice and specific explanations (177 documents/49 centres) and informed consent (36 documents/28 centres). The anthropological study was centred on the way information was given, evaluation of the patient's understanding and analysis of documents sent. CONCLUSION: This preliminary survey needs to be completed by a study, including the patient's point of view and needs, about the information given.

[Carboplatin and etoposide combination for the treatment of recurrent epithelial ovarian cancer]. / Association de carboplatine et étoposide dans le traitement des rechutes des cancers épithéliaux de l'ovaire.

UNLABELLED: The objective of this phase II study was to determine the efficacy and toxicity of a combination of carboplatin and etoposide as salvage treatment, in previously treated patients with persistent or recurrent ovarian cancer following first-line cisplatin-based chemotherapy. PATIENTS AND METHODS: From July 1990 to August 1994, 58 patients were treated with 3-week cycles of chemotherapy consisting of carboplatin (200 mg/m2, D1) and etoposide (120 mg/m2, D1, D2). Criteria for evaluating previous response to cisplatin were strictly defined. RESULTS: The overall response rate was 36%, with five complete responses (CR, 9%), 16 partial responses (PR, 27%) and the median duration of response was 10 months (range: 4 to 38). In the group of patients who progressed during the first year following the diagnosis, the response was 1 CR and 2 PR (12%) and in the group of patients who progressed from the second year after diagnosis, 4 CR and 14 PR (56%), with a median survival of 8.5 and 21 months respectively (p = 0.0013). The response rate was 59% in the potentially platinum sensitive group versus 8.7% in the primary resistant group (0.02 < p < 0.05). Myelotoxicity was the main side-effect but did not appear to be cumulative. Grade 3 and grade 4 anemia were observed in 26% and 3% of the patients respectively, neutropenia in 14% and 2% and thrombocytopenia in 14% and 8.5%. One patient died of sepsis associated with neutropenia. CONCLUSION: Treatment was easily manageable and well tolerated. The advantage of carboplatin and etoposide combination in potentially responsive patients is represented by the reduced nephrotoxicity, neurotoxicity and ototoxicity as compared with cisplatin containing regimen, with durable feasibility in outpatients. This second-line chemotherapy for ovarian cancer is effective as salvage treatment in potentially responsive patients with late recurrent tumors, while paclitaxel is the drug of choice for patients who have developped primary or secondary resistance to platin therapy.

Familial cluster of ovarian small cell carcinoma: a new mendelian entity?

We report a pedigree in which three sisters had a particular type of ovarian cancer, small cell carcinoma of the hypercalcaemic type. This rare type of ovarian carcinoma is now well characterised by clinical and pathological findings and is well distinguished from other ovarian epithelial tumours and ovarian germ cell tumours. The occurrence of this rare type of cancer in several members of the same family and the existence of four other similar published observations raises the question of the genetic determination of this kind of tumour.

Evaluation of whole abdominal irradiation in ovarian carcinoma with a four orthogonal fields technique.

PURPOSE: The purpose of this study is to evaluate the toxicity and the results of abdominopelvic irradiation with a four orthogonal field's technique in patients with ovarian carcinoma. METHODS AND MATERIALS: Between May 1981 and December 1990, 167 patients with ovarian carcinoma have been treated with whole abdominal irradiation: 62 patients with no or minimal residual disease < 2 cm after initial surgery (group 1) and 105 patients with no residual disease or macroscopic residual disease < 2 cm assessed by second-look surgery after incomplete debulking surgery and cisplatin-based polychemotherapy (group 2). Irradiation was performed by a four orthogonal field's technique. Thirty grays were given with a 25 MV photon beam (1.5 Gy/fraction/day, 20 fractions over 30 days). Boosts were performed in 50 cases (median dose of 15 Gy). RESULTS: With a median follow-up of 68 months, the 5-year actuarial survival rate was 50% in the entire group, 67% in group 1, 40% in group 2, and 84% in T1, 61.5% in T2, 38% in T3. Five-year actuarial survival was analyzed according to the residuum: (a) after initial surgery (no residual disease: 70%, residual disease: 36.5%), (b) after second-look surgery: 76% in patients with a negative second look, 66% in patients with microscopic residual disease, 22% in patients with macroscopic residual disease and secondary surgical reduction, and 10% in patients with small unresectable nodules. Nine percent of the patients failed to complete irradiation acute side effects related. Five percent required surgery for bowel obstruction. CONCLUSION: The abdominopelvic irradiation with this four orthogonal field's technique was associated with tolerable acute toxicity and a low risk of serious late complications. Similar late results to have been reported whole abdominal irradiation with chemotherapy in patients with negative or microscopic residual disease after surgery. Randomized trials comparing these two adjuvant treatments are warranted.

[Abdominopelvic radiation therapy in the treatment of ovarian carcinoma. Study of a continuous series of 167 patients]. / L'irradiation abdominopelvienne dans le traitement des cancers ovariens. Analyse d'une série continue de 167 patientes.

From May 1981 through December 1990, 167 patients with ovarian carcinoma were treated with whole abdominal irradiation. All patients of the first group (n = 62) presented with no or minimal (< 2 cm) residual disease at the time of irradiation. They received whole abdominal irradiation after initial surgery. Residual disease was left after initial surgery for patients of the second group (n = 105). They underwent a cisplatin polychemotherapy regimen followed by second-look laparotomy and abdominopelvic irradiation. The irradiation was performed by a four orthogonal field's technique. Thirty grays were given with a 25 MV photon beam. Boosts were performed in 50 cases (mean dose of 15 Gy); 91% have completed irradiation at the prescribed dose level; 5% had severe intestinal toxicity requiring surgery. The median follow-up was 68 months. The 5-year actuarial survival rate was 50%, 67% group 1.40% group 2. Five-year actuarial survival was 84% for T1, 61.5% for T2, 38% for T3. Five-year survival depended on tumor rest after initial surgery (residual disease 36.5%, no residual disease 70%). For patients in group 2, the size of residual disease at second-look laparotomy was a significant prognostic factor: five-year actuarial survival 76% with negative second-look, microscopic residual disease (positive cytology or random biopsies) 60%, microscopic disease after cytoreductive surgery at second-look 22%, macroscopic residual disease (small nodules) 10%. These results indicate that abdominopelvic irradiation is valuable in the treatment of ovarian carcinoma when there is no macroscopic residual disease after initial surgery or second look laparotomy. To assess the place of radiotherapy, randomized trials comparing whole abdominal irradiation with chemotherapy, watch policy for staged patients is warranted.

[Chemotherapy of cancers of the uterine cervix with a combination of bleomycin, mitomycin, cisplatin and etoposide]. / Chimiothérapie des cancers du col utérin par une association de bléomycine, mitomycine, cisplatine et étoposide.

Sixty patients with advanced carcinoma of the cervix were treated with 3-week cycles of chemotherapy consisting of bleomycin (10 mg/m2, D1, 2, 3), mitomycin (10 mg/m2, D1), cisplatin (80 mg/m2, D3), etoposide (100 mg/m2, D1, 2, 3). Twenty-six patients had prior therapy. Toxicities noted were primarily nausea, vomiting, asthenia, fever and myelosuppression, especially in the pre-treated patients. One patient died of pulmonary toxicity. Of the 34 untreated patients, 25 objective responses (74%) were observed, with two complete responses (6%) and among the 26 pre-treated patients, ten objective responses (39%) with only one complete response. The mean duration of response was 3.8 months [2-14]. These data indicate that combination chemotherapy regimen is active against advanced and recurrent cervical cancer but caution is required for administration and continuation of treatment after four cycles. This method of chemotherapy has significant potential for primary treatment in patients with locally advanced disease.

Telematics: a new tool for epidemiological surveillance of diarrhoeal diseases in the Aquitaine sentinel network.

A sentinel health information system using telematics and a network of general practitioners was set up in Aquitaine in south western France in 1986. Among the health problems under surveillance was acute diarrhoea. Data for each patient who fulfilled the usual case definition for acute diarrhoea were reported by general practitioners using home terminals (Minitels) connected to a central computer by telephone. Over one year 2234 cases of diarrhoea were reported, the incidence varying from 0.8 to 1.5 cases per doctor per week. Seasonal variations in incidence were observed, with peaks in the winter and in the summer. Only 379 (17%) episodes of diarrhoea were classified as severe, and these patients consulted their general practitioners earlier than patients whose diarrhoea was less severe. Foreign travel was rarely found in the patients' histories, but clusters of cases were found in communities (4.6%) and in families (22.3%). The advantages of this system were easy reporting and immediate feedback, but it was difficult to extrapolate the data, and the system was inadequate for intervening in outbreaks of diarrhoeal disease. Our knowledge of diarrhoeal diseases in south west France improved.

[First evaluation of three years of assessment of medical activity within the framework of PMSI in cancer prevention centers]. / Premier bilan de trois années de recueil de résumés standardisés de sortie dans le cadre du PMSI dans un centre de lutte contre le cancer.

In June 1982, the Direction of the French Hospitals introduced the project for the medicalisation of the system of information (PMSI) derived from the American Fetter system. The aim of this project was the collection of basic data necessary to the establishment of a national minimum data set base (MDS). Since 1985, a french regional cancer center, the Foundation Bergonié, has collected MDS by computer. Now, we give the results of the analysis concerning 28,379 MDS collected from 1986 to 1988. However, 11,127 (39%) MDS have not yet been analyzed by PMSI as they are connected with external activity or ambulatory care. It is possible to form a diagnosis related group (DRG) from the MDS to analyze the management of hospitals and utilization of means. 279 DRG were formed from 12,252 MDS, in our Institute. In fact, only 30 DRG with a sufficient number of MDS (over 100) were studied. This descriptive study shows that a few DRG maintain homogeneity in terms of length of hospitalisation especially in the surgical sector. It seems necessary to incorporate new criteria for MDS in order to improve the study of DRG; however groups sufficiently large for statistical analysis must be maintained.

Epidemiological surveillance of suicides and attempted suicides in Aquitaine, south-west France, using an original computer network of sentinel general practitioners.

To improve the epidemiological study of suicide and attempted suicides in Aquitaine, France, we developed a comprehensive surveillance system based on the input of Sentinel General Practitioners (SGPs). From October 1986 to May 1988, for each case of suicide or attempted suicide, the SGPs reported epidemiological data to our system through a computer network of personal home terminals (Minitels). Data included age, sex, method and result of attempt and antecedents. In an analysis of the relationship between the suicidal method, antecedents and results of suicidal act, the principal findings were a high rate of antecedents of suicide attempts by drug overdoses, hangings and drownings; and no antecedents for attempts by the use of firearms. This may show that the increasing accessibility of firearms is making it more likely that impulsive suicide attempts will be lethal.