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Numerous studies on the corrosion response of metal AM have been conducted. Nonetheless, the specimens being tested are commonly ground or polished to remove the outer as-built surface. If metal AM is truly going to be employed as a transformative technology that can produce complex shapes that do not require traditional machining, then the material needs to be evaluated in the as-built state. The reality is that AM alloys have shown significant inconsistencies regarding as-built surface texture, topology, and residual stress. One metric that has shown significant unpredictability in the literature is the susceptibility to localized corrosion of typically passive alloys, such as stainless steel (SS). There are a large number of studies that have attempted to understand the corrosion response of metal AM materials, but these studies are typically performed on materials that have been printed on a single machine and often mechanically polished to a smooth finish. This study compares the corrosion response of as-built AM, laser-beam powder bed fusion (LB-PBF), 316L SS parts that have been fabricated on five different machines. The majority of this work focused on understanding the susceptibility to localized corrosion of AM metals with respect to machine-dependent variables, namely surface roughness, and build angle. Surface roughness data was collected using scanning white light triangulation, laser scanning confocal microscopy, and coherence scanning interferometry. The results show that there is significant variability (ptwo-tail < 0.05) in the susceptibility to local corrosion initiation of LB-PBF 316L SS samples built on different machines. Surface oxides were probed with electron dispersive spectroscopy and revealed that variations in local corrosion susceptibility likely arise from differences in the stability of the passive film caused by chemical segregation, unique microstructure, and tortuous roughness features at the as-built surfaces. The variability of roughness and corrosion properties from test samples printed on different machines was corroborated by property measurements performed at five different testing sites, proving reproducibility of the data. Most importantly, this study shows that if the as-built surface layer is removed through grinding or electropolishing the machine-to-machine variation observed in the corrosion susceptibility is reduced.

Psychosocial interventions play an unclear complex role within maintenance treatment for opioid addiction. In this study, the hypothesis was that manualized psychosocial treatment was more effective than psychosocial treatment as usual. Moreover, the question was to find subgroups of patients who do not need or benefit from enhanced psychosocial treatment. The study design contains two manualized treatment groups and a control group of treatment as usual. There are two randomizations: (1) From the beginning, all patients were randomized to methadone or buprenorphine. (2) After having finished the control group treatment-as-usual, the subsequent patients were in addition randomly allocated to basic treatment or indicative treatment. From 122 patients in 3 treatment centers, 64 could be reached at the 1-year follow-up. Measurement instruments were the EuropASI, SCL-90, and documentation standards. Primary outcome criteria were drug consumption in the follow-up period of 6 months; secondary outcome criteria included individual changes in the EuropASI composite scores and the SCL-90 scales. Regarding hard drugs (all illegal drugs except cannabis, but including non-prescribed tranquilizers) the proportion of patient without use of drugs in the last 30 days increased from 1.9 % at intake to 54.7 % in the last month of the follow-up period without differences in the 3 psychosocial treatment groups. 76.1 % of those patients with at least one increased T-value (>60) in any of the 9 SCL scales showed at least one positive individual change in the follow-up period, whereas only 12.5 % of those with no increased T-value showed any positive changes. Regarding the use of hard drugs in the follow-up no psychosocial treatment was superior. The flexibility of psychosocial treatment as to meeting individual needs of the patients seems to be crucial. Those patients without a higher SCL-90 T-score may not require an intensive psychosocial treatment package.

A human recombinant L-type Ca2+ channel (alpha1C,77) was coexpressed with the rat angiotensin AT1A receptor in Xenopus laevis oocytes. In oocytes expressing only alpha1C,77 channels, application of human angiotensin II (1-10 microM) did not affect the amplitude or kinetics of Ba2+ currents (IBa). In sharp contrast, in oocytes coexpressing alpha1C,77 channels and AT1A receptors, application of 1 nM to 1 microM angiotensin gradually and reversibly inhibited IBa, without significantly changing its kinetics. The inhibitory effect of angiotensin on IBa was abolished in oocytes that had been preincubated with losartan (an AT1A receptor antagonist) or thapsigargin or injected with 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetate, pertussis toxin, guanosine-5'-O-(2-thio)diphosphate, or heparin, suggesting that the recombinant alpha1C channels were regulated by angiotensin through G protein-coupled AT1A receptors via activation of the inositol trisphosphate-dependent intracellular Ca2+ release pathway. Consistent with this hypothesis, no cross-signaling occurred between the AT1A receptor and a splice variant of alpha1C lacking Ca2+ sensors (alpha1C,86). The data suggest that the regulation of recombinant L-type Ca2+ channels by angiotensin is mediated by inositol trisphosphate-induced intracellular Ca2+ release and occurs at the molecular motif responsible for the Ca2+-induced inactivation of the channels.

The role of the calmodulin inhibitor trifluoperazine (TFP) in modulating the cellular levels and cytotoxicity in vitro and antitumour effects in vivo of doxorubicin (DOX), was evaluated in progressively DOX-resistant (5- to 40-fold) sublines of B16-BL6 mouse melanoma. In parental-sensitive B16-BL6 cells treated for 3 h, the IC50 of DOX was 0.1 microgram ml-1, and a less than 2-fold enhancement in DOX cell kill in the presence of a noncytotoxic concentration of 5 microM TFP was observed. However, in the DOX-resistant sublines, the IC50 was 0.7 to 5.0 micrograms ml-1 DOX in the absence of 5 microM TFP and 0.3 to 0.7 microgram ml-1 DOX in the presence of 5 microM TFP. The 2- to 7.5-fold decrease in the IC50 of DOX in the presence of 5 microM TFP, was dependent on the level of DOX-resistance in the various sublines. Compared to parental-sensitive cells, a 2-fold decrease in DOX-accumulation was evident only in the 40-fold DOX-resistant subline. Further, maximal enhancement (50%) of cellular DOX accumulation in the presence of 5 microM TFP was observed only in the 40-fold resistant cells treated with 5.0 micrograms ml-1 DOX. Retention of DOX in the 40-fold resistant subline was only 20% lower than similarly treated sensitive cells, and the inclusion of TFP increased DOX retention less than 10-15%. Antitumour studies in mice with experimental pulmonary metastases revealed that although DOX and DOX plus TFP had similar antitumour activity with the parental sensitive B16-BL6 cells, the combination of DOX plus TFP was significantly more effective than DOX alone with the DOX-resistant sublines. No overt toxicity was observed in normal mice treated with doses of TFP, DOX or DOX plus TFP used for in vivo chemotherapy studies. Results from this study suggest that gross cellular DOX levels do not appear to correlate with the magnitude of resistance, and the effects of TFP in modulating DOX resistance is possibly due to mechanisms other than mere alterations in cellular drug accumulation and/or retention.