High-power, widely tunable, room-temperature picosecond optical parametric oscillator based on cylindrical 5%MgO:PPLN.

We report a high-power picosecond optical parametric oscillator (OPO) based on cylindrical MgO:PPLN synchronously pumped by an Yb-fiber laser. The singly resonant OPO is tunable in the near-infrared signal across 1413-1900 nm and mid-infrared idler over 2418-4307 nm by angle tuning of the crystal at room temperature. With non-optimized output coupling of ∼10%, the OPO simultaneously delivers 2.4 W of signal at 1664 nm and 1.7 W of idler at 2950 nm at an overall extraction efficiency of ∼45% with high beam-pointing stability <30 µrad and <14 µrad for the signal and idler, respectively. The generated signal and idler exhibit passive power stability better than 1% rms and 0.8% rms over 15 h, respectively, in high beam quality with TEM(00) profile. The extracted signal pulses from the OPO have duration of 15.2 ps with a spectral bandwidth of 0.7 nm, corresponding to a time-bandwidth product of ΔυΔτ∼1.2.

Magneto- to electroactive transmutation of spin waves in ErMnO3.

The low-energy dynamical properties of the multiferroic hexagonal perovskite ErMnO3 have been studied by inelastic neutron scattering as well as terahertz and far infrared spectroscopies on a synchrotron source. From these complementary techniques, we have determined the magnon and crystal field spectra and identified a zone center magnon excitable only by the electric field of an electromagnetic wave. Using a comparison with the isostructural YMnO3 compound and crystal field calculations, we propose that this dynamical magnetoelectric process is due to the hybridization of a magnon with an electroactive crystal field transition.

[Two consecutive episodes of intracerebral hemorrhage as the presenting feature of polyarteritis nodosa]. / Deux hémorragies cérébrales révélatrices d'une périartérite noueuse.

We report a case of polyarteritis nodosa revealed by intracranial haemorrhage. A 40-year-old woman presented two episodes of cerebral haemorrhage twelve days apart, the second due to an aneurysm rupture. The diagnosis of polyarteritis nodosa (PAN) was based on the following criteria: histological aneurysm examination, angiography suggesting PAN with cerebral, renal and splenic localizations, loss of weight and cutaneous nodules. Cerebral haemorrhage in PAN is rare and exceptionally the presenting feature of the disease.

Second-harmonic generation in a doubly resonant semiconductor microcavity.

We demonstrate second-harmonic generation in a doubly resonant semiconductor microcavity. The monolithic cavity consists of an AlGaAs active medium sandwiched between two AlGaAs/AlAs dual-wavelength mirrors. The mirrors do not have any apparent periodicity because, unlike single- or dual-wavelength Bragg reflectors, they are engineered with dispersion taken into account. Quasi-phase matching is obtained by addition of the appropriate phases at reflection so as to compensate for the dephasing between the fundamental and the second-harmonic fields.

[Contribution of a hematologic cytogenetic laboratory to the diagnosis, classification and prognosis of various hematologic malignancies]. / Contribution d'un laboratoire de cytogénétique en hématologie, au diagnostic, à la classification et au pronostic de certaines hémopathies malignes.

The presence of an haematological cytogenetic laboratory into a clinical unit allowed to realize a close collaboration between clinicians and cytogeneticists, and to achieve a maximal exploitation of the results of the bone marrow cytogenetic studies in some haematological malignancies. It made it possible to perform sequential bone marrow karyotypes studies during the different phases of a disease: We could thus establish: The diagnostic value of cytogenetic findings for chronic myelocytic leukaemia, secondary acute leukaemia, but not for dysglobulinemias. The prognostic value of cytogenetic abnormalities in chronic myelocytic leukaemia where additional abnormalities to the Ph1 are a hallmark of blastic transformation; in primitive dysmyelopoiesis where they represent a bad prognostic factor; in dysglobulinemias, where they are a signal of terminal evolution. In all these diseases, only complex and multiple abnormalities have a prognostic significance pointing out the emergence of a malignant clone, where as rare and single abnormalities are of no significance. Nowadays, haematological cytogenetic must be bound to molecular biology.

[IgM myeloma: 6 cases and a review of the literature]. / Myélome à IgM: 6 observations et revue de la littérature.

IgM myeloma is a rare plasma cell neoplasia, with an estimated incidence of 0.5% in patients with myeloma. Approximately, between 2 and 3.3% of IgM monoclonal gammopathy are IgM myeloma. Six unpublished cases of IgM myeloma, association of an IgM monoclonal gammopathy and an exclusive plasma cell neoplasia, are reported. Forty-six other cases have been found in the literature. The initial clinical characteristics of these patients are: sex-ratio of 1.1, mean age of 62 years, fatigue in 95% of the cases, bone pain in 80%, osteolytic lesions in 78%, fever in 13%, hepatomegaly and splenomegaly in 8%, lymphadenopathy in 10%, hemorrhagic diathesis in 35% and neurologic involvement in 18%. Initial biological features are: anemia in 62% of the cases, creatininemia greater than 20 mg/l in 10%, calcemia greater than 120 mg/l in 24%. Mean serum IgM level is 33 g/l, mean medullary plasmocytosis is 52%. 80% of the patients presented with IgM kappa and only 20% with IgM lambda. Proteinuria with light chains are found in 65%. One-year survival is estimated at 82%, 2-year at 62%, 3-year at 46% with a median of 30 months. No prognostic factor is found. IgM myeloma with characteristics of both myeloma and macroglobulinemia appears well individualized among B-cell neoplasia. However, the distinction between Waldenström's macroglobulinemia and IgM myeloma can be difficult in case of lympho-plasmocytic bone marrow proliferation with osteolytic lesions.

Refractory anemia with excess of blasts in transformation. Clinical, hematologic, and cytogenetic findings in nine patients.

Clinical, hematologic, and cytogenetic data of nine patients with refractory anemia with excess of blasts in transformation (RAEB-t), classified according to the French-American-British Cooperative Group for myelodysplastic syndrome (MDS), are reported. At diagnosis, eight out of nine cases, had chromosomal abnormalities and three out of nine developed acute leukemia. Karyotype studies allowed individualization of two groups of patients: five with nonrandom major karyotype abnormalities (MAKA) including hypodiploidy, chromosomes 5 and 7 involvement, at least four other abnormalities, and a poor prognosis (survival always under 3.5 months); and four patients with either normal karyotypes or minor karyotype abnormalities (MIKA) (no more than three abnormalities) and a better prognosis (survival from 14 to 38 months). Karyotype appears to be a major prognostic factor among RAEB-t.

[Chemotherapy in cancer of colon. General review]. / La chimiothérapie dans le cancer du côlon. Revue générale.

The results of surgery as sole treatment of colon cancer are summarized before dealing with those of chemotherapy. Curative or palliative chemotherapy remains controverted. The results of single drug treatments and of the conventional protocols with 5-fluorouracil and nitrosoureas have been disappointing. A promising approach is modulation of 5-fluorouracil by folinic acid, with a response rate of up to 45 p 100, and potentiation of 5-fluorouracil by cisplatin. Intra-arterial chemotherapy has been, and still is, an interesting method in liver metastases, but recent studies and the experience acquired with prolonged follow-ups have thrown doubts on some of its results, notably survival. Adjuvant chemotherapy is even more controversial than curative chemotherapy; however, a recent controlled study has yielded favourable results, and the best drug combinations have not yet been tested. It is concluded that cancers of the colon have shown some chemosensitivity, even though it has not reached the same level as that of cancers of other organs.

Sequential karyotype study on Ph-positive chronic myelocytic leukemia. Significance of additional chromosomal abnormalities during disease evolution.

Twenty-eight patients with Ph-positive chronic myelocytic leukemia (CML), who all died of the disease, had cytogenetic studies throughout the progression of the disease: at diagnosis, during chronic phase (CP), accelerated phase (AP), and blastic transformation (BT). The aim of this sequential study was to appreciate the frequency and the significance of additional chromosomal abnormalities (ACA) during CML evolution, especially in the CP. In our series ACA were rare (five of 28 patients) and simple (four of five) in CP. They were much more frequent and complex in AP (11 of 16) and in BT (22 of 24) with complex abnormalities (13 of 24). In CP, ACA predictive value for metamorphosis was poor: only three of 13 patients had ACA within 1 year before BT, and only two of 11 within 1 year before AP. ACA were mainly observed during the last period before BT: ten of 17 patients studied within 6 months prior BT had ACA, but by then two of three were in AP. ACA, especially when complex, appear to be a hallmark of CML metamorphosis.

Antibody against human lipoprotein lipase.

A polyclonal antibody against human lipoprotein lipase (LPL) was prepared. LPL from post-heparin plasma was first purified by heparin Sepharose 4B affinity chromatography. Protein impurities co-eluted with LPL were then eliminated by electrophoresis in the presence of ampholytes. Antithrombin III was identified in this fraction of protein impurities by immunodiffusion against a human antithrombin antiserum, while no antithrombin III could be detected in the purified LPL fraction. Immunodiffusion revealed a single line of precipitation between this antibody and human post-heparin plasma LPL. When pre-incubated with a constant activity of highly purified post-heparin plasma LPL (2.7 mU/75 microliters), an equal volume of the anti-LPL antiserum, either pure or diluted to 1/32 caused complete inhibition of the enzyme activity. Half maximal inhibition was observed at a dilution of approximately 1/200. By using a secondary antibody, it was shown that antiserum inhibited LPL activity by means of its immunoglobulins. This antibody was able to inhibit LPL from human adipose tissue, indicating that human LPL released from endothelial cell membranes has common antigenic determinants with adipose tissue LPL.

Cytogenetic studies in twelve patients with primary myelofibrosis and myeloid metaplasia.

Chromosome studies on bone marrow and/or peripheral blood cells without phytohemagglutinin were performed on 12 patients with primary myelofibrosis with myeloid meta-plasia (PMMM) between 1980 and 1984. Abnormal clones were found in six patients (50%). In five cases the abnormal clone involved the long arm of chromosome #7, two of which also had partial trisomy of chromosome #1 and trisomy of 9. Additional abnormalities involving chromosomes #3, #5, #11, #13, #15, and #21 were each found once. Review of the literature showed few studies on the cytogenetics of PMMM. No specific chromosomal pattern can be established; however, abnormalities described are nonrandom.

[The combination of epirubicin, bleomycin, vinblastine and prednisone (EBVP) before radiotherapy in localized stages of Hodgkin's disease. Phase II trials]. / Association d'épirubicine, bléomycine, vinblastine et prednisone (EBVP) avant radiotherapie dans les stades localisés de la maladie de Hodgkin. Essai de phase II.

A new regimen of chemotherapy was used to reduce toxicity of ABVD: adriamycin is replaced by epirubicin and dacarbazine by prednisone. Thirty eight patients with Hodgkin's disease, stage I to IIIA, previously untreated, received three courses of this regimen before radical radiotherapy. Gastro-intestinal toxicity and alopecia appeared less marked than with ABVD. Immediate efficacy is similar with 80% of complete remission (one third observed at day 28) and only 2 failures. This regimen appears thus as a clear improvement in the treatment of patients with Hodgkin's disease and deserves larger comparison with previously used chemotherapy in a more extensive controlled trial.