The Polyol Process and the Synthesis of ζ Intermetallic Compound Ag5Sn0.9

The present work concerns the intermetallic compound (IMC) existing in the Ag–Sn system and its potential use in electronics as attachment materials allowing the adhesion of the chip to the substrate forming the power module. First, we present the synthesis protocol in polyol medium of a compound with the chemical formula Ag₅Sn_0.9 belonging to the solid solution of composition located between 9 and 16 at.% Sn, known as solid solution ζ (or ζ-Ag₄Sn). This phase corresponds to the peritectic invariant point at 724 °C. Differential thermal analysis and X-ray dispersive analysis confirm the single-phased (monocrystalline) nature of the Ag₅Sn_0.9 powder issued after synthesis. Scanning electron microscopy shows that Ag₅Sn_0.9 particles are spherical, and range in submicronic size of around 0.18 μm. X-ray diffraction analysis reveals that the ζ phase mostly exists under the two allotropic varieties (orthorhombic symmetry and hexagonal symmetry) with however a slight excess of the hexagonal variety (60% for the hexagonal variety and 40% for the orthorhombic variety). The lattice parameters resulting from this study for the two allotropic varieties are in good agreement with the Hume-Rothery rules.     

The Impact of Organised Screening Programs on Breast Cancer Stage at Diagnosis for Canadian Women Aged 40–49 and 50–59

The relationship between Canadian mammography screening practices for women 40–49 and breast cancer (BC) stage at diagnosis in women 40–49 and 50–59 years was assessed using data from the Canadian Cancer Registry, provincial/territorial screening practices, and screening information from the Canadian Community Health Survey. For the 2010 to 2017 period, women aged 40–49 were diagnosed with lesser relative proportions of stage I BC (35.7 vs. 45.3%; p < 0.001), but greater proportions of stage II (42.6 vs. 36.7%, p < 0.001) and III (17.3 vs. 13.1%, p < 0.001) compared to women 50–59. Stage IV was lower among women 40–49 than 50–59 (4.4% vs. 4.8%, p = 0.005). Jurisdictions with organised screening programs for women 40–49 with annual recall (screeners) were compared with those without (comparators). Women aged 40–49 in comparator jurisdictions had higher proportions of stages II (43.7% vs. 40.7%, p < 0.001), III (18.3% vs. 15.6%, p < 0.001) and IV (4.6% vs. 3.9%, p = 0.001) compared to their peers in screener jurisdictions. Based on screening practices for women aged 40–49, women aged 50–59 had higher proportions of stages II (37.2% vs. 36.0%, p = 0.003) and III (13.6% vs. 12.3%, p < 0.001) in the comparator versus screener groups. The results of this study can be used to reassess the optimum lower age for BC screening in Canada.     

TIPS for portal decompression to allow palliative treatment of adenocarcinoma of the esophagus

We describe a case in which a transjugular intrahepatic portosystemic shunt (TIPS) was inserted to enable palliative treatment of an adenocarcinoma of the esophagus. The cirrhotic patient presented with esophageal varices in contact with a tumor of the esophagus. By relieving portal pressure, TIPS reduced the risk of hemorrhage during laser resection and prevented recurrence of esophageal varices.     

Local treatment options for ipsilateral breast tumour recurrence

Purpose

In case of ipsilateral breast tumour recurrence (IBTR), radical mastectomy represents the treatment option frequently proposed. A second conservative treatment (2ndCT) has been proposed using either lumpectomy alone or associated with a re-irradiation of the tumor bed. However, in both clinical situations, the proof level of such therapeutic approaches remains low, based on cased-series or retrospective studies (level C).

Material and methods

In order to assess the different strategies of local treatment proposed in case of IBTR, a PubMed literature review was performed using the following keywords: breast cancer, ipsilateral recurrence, mastectomy, radiation therapy, brachytherapy. Four different salvage options were analyzed: (a) salvage mastectomy alone; (b) salvage mastectomy with postoperative re-irradiation; (c) 2ndCT with surgery alone; (d) 2ndCT with re-irradiation.

Results

The rate of second local recurrence is about 10% [3–32%], about 25% [7–36%] and about 10% [2–26%], after salvage mastectomy, salvage lumpectomy alone or combined with a re-irradiation of the tumor bed respectively.However, the 5-year overall survival rates after salvage mastectomy and 2ndCT seem to be equivalent (≈75%) mainly influenced by distant metastatic progression.

Conclusion

In terms of Evidence Based Medicine, different options can be discussed such as Phase III or II randomized trials comparing salvage mastectomy versus 2ndCT, retrospective studies based on a matched-pair analysis or observatory studies. Those study designs need to be carefully analyzed to be able to propose new treatment options for women who experience an IBCR.     

Blood pressure disorders during Parkinson's disease: epidemiology, pathophysiology and management

Blood pressure disorders are highly prevalent in the course of Parkinson's disease (PD). They relate to autonomic failure and are frequently associated with orthostatic hypotension, postprandial hypotension and supine hypertension. Supine hypertension, which may concern up to 50% of patients with PD and autonomic failure, is driven by residual sympathetic activity and changes in sensitivity of vascular adrenergic receptors. It can also be induced or worsened by antihypotensive drugs. Even if little data is available, a set of arguments suggests that supine hypertension sometimes requires treatment. This review will focus on recent data on the pathophysiology and the management of supine hypertension in the context of its association with orthostatic hypotension.     

Ambulatory blood pressure in patients with Parkinson's disease without and with orthostatic hypotension

Non-invasive ambulatory recordings of blood pressure and heart rate were performed using a Spacelabs device during day and night periods in patients with Parkinson's disease with (n = 19) or without orthostatic hypotension (n = 19). In patients with orthostatic hypotension, the average systolic and diastolic blood pressure during the night (137 ± 5/80 ± 3 mmHg) was higher (p < 0.05) than during the day period (121 ± 3/76 ± 2 mmHg). In patients without orthostatic hypotension, a decrease in blood pressure was recorded during the nocturnal period. In patients with orthostatic hypotension, the blood pressure variability was higher (p < 0.05) during the day (systolic: 14.6 ± 1.3%; diastolic: 16.5 ± 1.0%) than during the night (systolic: 9.1 ± 0.8%; diastolic: 10.8 ± 1.1%). The blood pressure load (percentage of values above 140/90 mmHg) during the night was significantly higher than during the day for both systolic (41.2 ± 8.1 vs. 19.6 ± 4.7%) and diastolic blood pressure (24.9 ± 6.9 vs. 16.3 ± 4.9%). There was a decrease in heart rate in both groups during the night. A fall of 25 mmHg or more in systolic blood pressure after meals occurred in ten patients with orthostatic hypotension and in one patient without orthostatic hypotension. These results indicate that orthostatic hypotension in Parkinson's disease is associated with specific modifications of ambulatory blood pressure including loss of circadian rhythm of blood pressure, increased diurnal blood pressure variability and post-prandial hypotension.     

From bradykinin B2 receptor antagonists to orally active and selective bradykinin B1 receptor antagonists

The bradykinin (BK) B1 receptor is an attractive target for the treatment of chronic pain and inflammation. Starting from a dual B1 and B2 antagonist, novel antagonists were designed that display low-nanomolar affinity for human B1 receptor and selectivity over B2. Initially, potent imidazoline derivatives were studied, but these compounds suffered from low bioavailability. This issue could be overcome by the use of less basic amino derivatives leading to orally active compounds.     

Differential β2-adrenergic receptor expression defines the phenotype of non-tumorigenic and malignant human breast cell lines

Breast cancer is the most frequent malignancy in women. Several reports demonstrated that adrenergic receptors (ARs) are involved in breast cancer. Here we observed that epinephrine (Epi), an endogenous AR agonist, caused opposite effects in non-tumorigenic (MCF-10A and HBL-100) and tumor cells (MCF-7 and MDA-MB-231). Thus, Epi, in non-tumor breast cells, as well as isoproterenol (β-agonist), in all cell lines, maintained a benign phenotype, decreasing cell proliferation and migration, and stimulating cell adhesion. β-AR expression and cAMP levels were higher in MCF-10A than in MCF-7 cells. β₂-AR knock-down caused a significant increase of cell proliferation and migration, and a decrease of cell adhesion both in basal and in Iso-stimulated conditions. Coincidently, β₂-AR over-expression induced a significant decrease of cell proliferation and migration, and an increase of cell adhesion. Therefore, β₂-AR is implied in cell phenotype and its agonists or antagonists could eventually complement cancer therapy.