Ultra-broadband EPR spectroscopy in field and frequency domains.

Electron paramagnetic resonance (EPR) is a powerful technique to investigate the electronic and magnetic properties of a wide range of materials. We present the first combined terahertz (THz) field and frequency domain electron paramagnetic resonance (HFEPR/FDMR) spectrometer designed to investigate the electronic structure and magnetic properties of molecular systems, thin films and solid state materials in a very broad frequency range of 85-1100 GHz. In this paper, we show high resolution frequency-field (Zeeman) maps (170-380 GHz by 0-15 T) recorded on two single-molecule magnets, [Mn2(saltmen)2(ReO4)2] and [Mn2(salpn)2(H2O)2](ClO4)2, which give direct access to the field-dependence of the energy level diagram. Furthermore, supression of standing waves in the described system and the sensitivity in field and frequency domain operations is evaluated and discussed.

[Progress of Rehabilitation for Cardiac Patients Depending on the Degree of Self-Sufficiency at Admission]. / Verlauf der Rehabilitation bei kardiologischen Patienten in Abhängigkeit vom Selbstversorgungsgrad bei Aufnahme.

INTRODUCTION: There are hardly any publications about the outcome of cardiac rehabilitation considering patients with an increased need for medical, nursing and therapeutic care. The aim of this study, which consecutively included n=387 statutory health insurance inpatients over a period of 2 years, was to find out differences in outcome in self-care patients (Barthel index>70) as compared to patients with a need for complex care (Barthel index≤70). METHODS: Rehabilitation outcomes concerning physical capacity, emotional status and activities of daily living as measured by Barthel index, FIM index, HADS, clinical complications, exercise test, duration of rehabilitation and form of dismission were analyzed and compared between both groups. RESULTS: The inpatients with a Barthel index ≤70 at admission were older, had a longer stay in hospital and in rehabilitation, developed more complications and more often suffered from concomitant diseases. They were readmitted to hospital more often. They showed a comparatively higher increase in indices of self-care and a significant increase in physical performance tests. CONCLUSION: Higher medical care expenses of multimorbid cardiac inpatients are no contraindication against rehabilitation, because even in this group the specific rehabilitation aims of the healthcare payers can be reached.

KOOS pain as a marker for significant knee pain two and six years after primary ACL reconstruction: a Multicenter Orthopaedic Outcomes Network (MOON) prospective longitudinal cohort study.

OBJECTIVE: The prevalence of radiographic osteoarthritis (OA) after anterior cruciate ligament reconstruction (ACLR) approaches 50%, yet the prevalence of significant knee pain is unknown. We applied three different models of Knee injury and Osteoarthritis Outcome Score (KOOS) thresholds for significant knee pain to an ACLR cohort to identify prevalence and risk factors. DESIGN: Multicenter Orthopaedic Outcomes Network (MOON) prospective cohort patients with a unilateral primary ACLR and normal contralateral knee were assessed at 2 and 6 years. Independent variables included patient demographics, validated Patient Reported Outcomes (PRO; Marx activity score, KOOS), and surgical characteristics. Models included: (1) KOOS criteria for a painful knee = quality of life subscale <87.5 and ≥2 of: KOOSpain <86.1, KOOSsymptoms <85.7, KOOSADL <86.8, or KOOSsports/rec <85.0; (2) KOOSpain subscale score ≤72 (≥2 standard deviations below population mean); (3) 10-point KOOSpain drop from 2 to 6 years. Proportional odds models (alpha ≤ 0.05) were used. RESULTS: 1761 patients of median age 23 years, median body mass index (BMI) 24.8 kg/m(2) and 56% male met inclusion, with 87% (1530/1761) and 86% (1506/1761) follow-up at 2 and 6 years, respectively. At 6 years, n = 592 (39%), n = 131 (9%) and n = 169 (12%) met criteria for models #1 through #3, respectively. The most consistent and strongest independent risk factor at both time-points was subsequent ipsilateral knee surgery. Low 2-year Marx activity score increased the odds of a painful knee at 6 years. CONCLUSIONS: Significant knee pain is prevalent after ACLR; with those who undergo subsequent ipsilateral surgery at greatest risk. The relationship between pain and structural OA warrants further study.

SH+ 360: novel model for scaling up a mental health and psychosocial support programme in humanitarian settings.

We explore multi-sectoral integration as a model for scaling up evidence-based mental health and psychosocial support interventions in humanitarian settings. We introduce Self Help Plus 360, designed to support humanitarian partners across different sectors to integrate a psychosocial intervention into their programming and more holistically address population needs.

Trajectories of psychosocial symptoms and wellbeing in asylum seekers and refugees exposed to traumatic events and resettled in Western Europe, Turkey, and Uganda.

Background: Longitudinal studies examining mental health trajectories in refugees and asylum seekers are scarce. Objectives: To investigate trajectories of psychological symptoms and wellbeing in refugees and asylum seekers, and identify factors associated with these trajectories. Method: 912 asylum seekers and refugees from the control arm of three trials in Europe (n = 229), Turkey (n = 320), and Uganda (n = 363) were included. We described trajectories of psychological symptoms and wellbeing, and used trauma exposure, age, marital status, education, and individual trial as predictors. Then, we assessed the bidirectional interactions between wellbeing and psychological symptoms, and the effect of each predictor on each outcome controlling for baseline values. Results: Symptom improvement was identified in all trials, and for wellbeing in 64.7% of participants in Europe and Turkey, versus 31.5% in Uganda. In Europe and Turkey domestic violence predicted increased symptoms at post-intervention (ß = 1.36, 95% CI 0.17-2.56), whilst murder of family members at 6-month follow-up (ß = 1.23, 95% CI 0.27-2.19). Lower wellbeing was predicted by murder of family member (ß = -1.69, 95% CI -3.06 to -0.32), having been kidnapped (ß = -1.67, 95% CI -3.19 to -0.15), close to death (ß = -1.38, 95% CI -2.70 to -0.06), and being in the host country ≥2 years (ß = -1.60, 95% CI -3.05 to -0.14). In Uganda at post-intervention, having been kidnapped predicted increased symptoms (ß = 2.11, 95% CI 0.58-3.65), and lack of shelter (ß = -2.51, 95% CI -4.44 to -0.58) and domestic violence predicted lower wellbeing (ß = -1.36, 95% CI -2.67 to -0.05). Conclusion: Many participants adapt to adversity, but contextual factors play a critical role in determining mental health trajectories.

Antecedentes: Estudios longitudinales que examinan las trayectorias de la salud mental en los refugiados y solicitantes de asilo son escasos.Objetivos: Investigar las trayectorias de los síntomas psicológicos y el bienestar en refugiados y solicitantes de asilo, e identificar factores asociados a estas trayectorias.Métodos: Se incluyeron 912 solicitantes de asilos y refugiados del brazo control de tres ensayos clínicos en Europa (n = 229), Turquía (n = 320) y Uganda (n = 363). Describimos las trayectorias psicológicas de los síntomas y el bienestar, y utilizamos la exposición traumática, la edad, el estado marital, la educación y el juicio individual como predictores. Después, evaluamos las interacciones bidireccionales entre el bienestar y los síntomas psicológicos, y el efecto de cada uno de los predictores en cada resultado controlando por los valores iniciales.Resultados: Se identificó una mejoría en los síntomas en todos los ensayos, y del bienestar en el 64.7% de los participantes en Europa y Turquía, versus el 31.5% en Uganda. En Europa y en Turquía, la violencia doméstica predijo el incremento de síntomas de después de la intervención (ß = 1.36, 95% CI 0.17 a 2.56), mientras que el homicidio de algún miembro familiar a los 6 meses de seguimiento (ß = 1.23, 95% CI 0.27 a 2.19). Un menor bienestar fue predicho por el homicidio de algún miembro de la familia (ß = −1.69, 95% CI −3.06 a −0.32), haber sido secuestrado (ß = −1.67, 95% CI −3.19 a −0.15), haber estado próximo a la muerte (ß = −1.38, 95% CI −2.70 a −0.06), y estar en el país de acogida ≥2 años (ß = −1.60, 95% CI −3.05 a −0.14). En Uganda, después de la intervención, haber sido secuestrado predijo un aumento de los síntomas (ß =2.11, 95% CI 0.58 a 3.65), y la falta de refugio (ß = −2.51, 95% CI −4.44 a −0.58) y la violencia doméstica predijo un menor bienestar (ß = −1.36, 95% CI −2.67 a −0.05).Conclusión: Muchos participantes se adaptan a la adversidad, pero los factores contextuales juegan un papel crítico en determinar las trayectorias de la salud mental.

Reliability of lower extremity alignment measurement using radiographs and PACS.

PURPOSE: Lower extremity alignment is an important consideration prior to cartilage surgery and/or osteotomy about the knee. This is measured on full length standing hip to ankle radiographs, which has traditionally been done using hard copy radiographs. However, the advent of PACS (Picture Archiving and Communication Systems) has allowed these measurements to be done on computer based digital radiographs. The objectives of this study were to evaluate the intra- and inter-observer reliability of lower limb alignment measures manually obtained from hard copy radiographs versus using the Philips Easy Vision system, and to assess the subjective ease of use for the two methods. METHODS: Forty-two patients who underwent surgery and who had a standing hip to ankle radiograph on file were identified. Four raters, including two radiologists and two orthopaedic surgeons, measured each hard copy radiograph and computer image on two separate occasions. Three measurements were recorded for each hard copy radiograph and computer image-width of tibial plateau, the distance from the medial aspect of the tibial plateau to the weight-bearing line, and the mechanical axis. RESULTS: All correlations for this study were high. For tibial plateau data, the hard copy radiographs compared to PACS demonstrated intra-class correlation coefficients (ICC) ranging from 0.93 to 0.99 for inter-rater reliability for the four raters. The ICC for intra-rater reliability for hard copies ranged from 0.90 to 0.99 and for PACS from 0.94 to 0.99. The inter-rater data comparing raters ranged from 0.87 to 0.98 for hard copy radiographs and from 0.98 to 0.99 for PACS. For mechanical axis data, the ICC for hard copy radiograph compared to PACS ranged from 0.93 to 0.97 for the intra-rater reliability for the four raters. The intra-rater reliability for mechanical axis data on hard copy radiograph ranged from an ICC of 0.86 to 0.96, and for PACS the ICC ranged from 0.93 to 0.99. The inter-observer data for hard copy radiographs using the mechanical axis ranged from 0.88 to 0.94 and for PACS ranged from 0.93 to 0.97. The physicians rated PACS as statistically significantly easier to use when compared to hard copy (P = 0.03). CONCLUSION: Evaluation of lower extremity alignment using two techniques prior to knee surgery was found to have higher inter- and intra-observer reliability using PACS software. PACS is now used prior to cartilage surgery and/or osteotomy to measure both alignment and the location of the weight bearing line on the tibial plateau both before and after surgery. LEVEL OF EVIDENCE: Diagnostic study, Level I.

Guided self-help to reduce psychological distress in South Sudanese female refugees in Uganda: a cluster randomised trial.

BACKGROUND: Innovative solutions are required to provide mental health support at scale in low-resource humanitarian contexts. We aimed to assess the effectiveness of a facilitator-guided, group-based, self-help intervention (Self-Help Plus) to reduce psychological distress in female refugees. METHODS: We did a cluster randomised trial in rural refugee settlements in northern Uganda. Participants were female South Sudanese refugees with at least moderate levels of psychological distress (cutoff ≥5 on the Kessler 6). The intervention comprised access to usual care and five 2-h audio-recorded stress-management workshops (20-30 refugees) led by briefly trained lay facilitators, accompanied by an illustrated self-help book. Villages were randomly assigned to either intervention (Self-Help Plus or enhanced usual care) on a 1:1 basis. Within 14 villages, randomly selected households were approached. Screening of women in households continued until 20-30 eligible participants were identified per site. The primary outcome was individual psychological distress, assessed using the Kessler 6 symptom checklist 1 week before, 1 week after, and 3 months after intervention, in the intention-to-treat population. All outcomes were measured at the individual (rather than cluster) level. Secondary outcomes included personally identified problems, post-traumatic stress, depression symptoms, feelings of anger, social interactions with other ethnic groups, functional impairment, and subjective wellbeing. Assessors were masked to allocation. This trial was prospectively registered at ISRCTN, number 50148022. FINDINGS: Of 694 eligible participants (331 Self-Help Plus, 363 enhanced usual care), 613 (88%) completed all assessments. Compared with controls, we found stronger improvements for Self-Help Plus on psychological distress 3 months post intervention (ß -1·20, 95% CI -2·33 to -0·08; p=0·04; d -0·26). We also found larger improvements for Self-Help Plus 3 months post-intervention for five of eight secondary outcomes (effect size range -0·30 to -0·36). Refugees with different trauma exposure, length of time in settlements, and initial psychological distress benefited similarly. With regard to safety considerations, the independent data safety management board responded to six adverse events, and none were evaluated to be concerns in response to the intervention. INTERPRETATION: Self-Help Plus is an innovative, facilitator-guided, group-based self-help intervention that can be rapidly deployed to large numbers of participants, and resulted in meaningful reductions in psychological distress at 3 months among South Sudanese female refugees. FUNDING: Research for Health in Humanitarian Crises (R2HC) Programme.

Improving mental health and psychosocial wellbeing in humanitarian settings: reflections on research funded through R2HC.

Major knowledge gaps remain concerning the most effective ways to address mental health and psychosocial needs of populations affected by humanitarian crises. The Research for Health in Humanitarian Crisis (R2HC) program aims to strengthen humanitarian health practice and policy through research. As a significant portion of R2HC's research has focused on mental health and psychosocial support interventions, the program has been interested in strengthening a community of practice in this field. Following a meeting between grantees, we set out to provide an overview of the R2HC portfolio, and draw lessons learned. In this paper, we discuss the mental health and psychosocial support-focused research projects funded by R2HC; review the implications of initial findings from this research portfolio; and highlight four remaining knowledge gaps in this field. Between 2014 and 2019, R2HC funded 18 academic-practitioner partnerships focused on mental health and psychosocial support, comprising 38% of the overall portfolio (18 of 48 projects) at a value of approximately 7.2 million GBP. All projects have focused on evaluating the impact of interventions. In line with consensus-based recommendations to consider a wide range of mental health and psychosocial needs in humanitarian settings, research projects have evaluated diverse interventions. Findings so far have both challenged and confirmed widely-held assumptions about the effectiveness of mental health and psychosocial interventions in humanitarian settings. They point to the importance of building effective, sustained, and diverse partnerships between scholars, humanitarian practitioners, and funders, to ensure long-term program improvements and appropriate evidence-informed decision making. Further research needs to fill knowledge gaps regarding how to: scale-up interventions that have been found to be effective (e.g., questions related to integration across sectors, adaptation of interventions across different contexts, and optimal care systems); address neglected mental health conditions and populations (e.g., elderly, people with disabilities, sexual minorities, people with severe, pre-existing mental disorders); build on available local resources and supports (e.g., how to build on traditional, religious healing and community-wide social support practices); and ensure equity, quality, fidelity, and sustainability for interventions in real-world contexts (e.g., answering questions about how interventions from controlled studies can be transferred to more representative humanitarian contexts).

Local cytokine profiles in knee osteoarthritis: elevated synovial fluid interleukin-15 differentiates early from end-stage disease.

OBJECTIVE: Much of what is known about the inflammatory response in the synovial membrane (SM) of patients with osteoarthritis (OA) comes from studies of synovial tissues from end-stage disease. In this study, we sought to better characterize the inflammatory infiltrate in symptomatic patients with early signs of knee OA, and to determine how inflammatory cell populations relate to the pattern of cytokine and degradative enzyme production. METHODS: Study populations comprised patients with degenerative meniscal tears and early cartilage thinning undergoing arthroscopic procedures (early OA) and patients undergoing total knee replacement for end-stage OA. Quantitative real-time polymerase chain reaction (PCR) was used to measure expression of SM cytokines and enzymes implicated in the pathogenesis of inflammatory arthritis and OA, as well as cell lineage-specific markers. We quantified synovial fluid (SF) cytokines and enzymes by enzyme-linked immunosorbent assay (ELISA) and SM cell populations by immunohistochemistry. RESULTS: We found increased levels of SF interleukin-15 (IL-15) protein in the early knee OA patients when compared to end-stage OA. Both SF IL-15 protein and numbers of CD8 cells within SM correlated with matrix metalloproteinase-1 (MMP-1) and three levels. TNF-alpha, IL-6 and IL-21 were also detectable in the SF of the majority of patients, and IL-15 levels were associated with IL-6 levels. CONCLUSION: IL-15 is elevated in early knee OA, suggesting activation of an innate immune response in the SM. The association of IL-15 expression with CD8 transcripts and MMPs implicates this cytokine in OA pathogenesis and as a candidate therapeutic target.

Effect of bavistin on in vitro plant conversion from encapsulated uninodal microcuttings of micropropagated Bacopa monnieri (L.)--an Ayurvedic herb.

A reliable and reproducible protocol for contamination free plant recovery system from alginated encapsulated uninodal microcuttings of micropropagated Bacopa monnieri L. have been developed after storage at 18 degrees C for 45 days. Node segments excised from freshly micropropagated plants were encapsulated as single explant beads with 3.0% sodium alginate and 80 mM CaCl2 2 H2O. To find out the optimal concentration of fungicide bavistin for efficient plant recovery different concentrations of bavistin (1.0 - 15 mg l(-1)) were incorporated in to the encapsulation medium. 3.0mg l(-1) bavistin showed no reduction in plant conversion and generated maximum number of shoots (45.6 +/- 1.69) at high frequency with out any contamination after storage up to 45 days at 18 degrees C. At high concentrations (13 and 15 mg l(-1)), rupturing of calcium alginate coats after 8 - 9 days and gradual decline in the number of shoots indicates the toxic effect of bavistin on plant conversion. Encapsulated node cuttings stored up to 45 days regenerated shoots (5.2) and multiple shoots (45.6) in MS basal and hormone medium respectively. Maximum shoot length (8.2 +/- 0.37 cm) was observed from encapsulsted node cuttings incorporated with 3.0 mg l(-1) bavistin on MS basal medium. 90% of the recovered plantlets were hardened off and successfully established in soil.

Regulation of 1,25-dihydroxyvitamin D3 receptor gene expression by 1,25-dihydroxyvitamin D3 in the parathyroid in vivo.

1,25-Dihydroxyvitamin D3 (1,25(OH)2D3 dramatically decreases parathyroid hormone (PTH) gene transcription. We have now studied the effect of 1,25(OH)2D3 on the 1,25(OH)2D receptor (VDR) in the parathyroid in vivo. Rats were injected with 1,25(OH)2D3 and the parathyroid-thyroid tissue analyzed for PTHmRNA and VDRmRNA. 1,25(OH)2D3 (50 and 100 pmol ip) decreased PTHmRNA at 6 h with a maximum at 48 h (less than 4% of basal), whereas VDRmRNA was increased only after 6 h with a 1.7-fold increase at 24 h. VDRmRNA levels peaked at 25 pmol 1,25(OH)2D3 with a twofold increase. Serum calcium did not affect VDRmRNA. Parathyroid VDRmRNA ran at 2.2 and 4.4 kb, whereas duodenum VDRmRNA had a single band, all of which increased after 1,25(OH)2D3. Weanling rats on a vitamin D-deficient diet for 3 wk had a more intense 2.2-kb transcript, whereas vitamin D-replete rats had a more intense 4.4-kb band. Dispersed parathyroid-thyroid cells were separated by a flow cytometry (FACS) into a parathyroid cell peak containing PTHmRNA and a second peak with cells positive for thyro-globulin mRNA and calcitonin mRNA. VDRmRNA was concentrated in the parathyroid cell peak. In situ hybridization of parathyroid-thyroid and duodenum for VDRmRNA showed its localization to the parathyroid cells and the duodenal mucosa. Therefore, the VDRmRNA in the parathyroid-thyroid tissue represents predominantly parathyroid cell and not C-cell VDRmRNA which is also a 1,25(OH)2D3 target organ. The increased VDR gene expression in the parathyroid cell would amplify the effect of 1,25(OH)2D3 to decrease PTH gene transcription.

Co-Localization of Macrophage Inhibitory Factor and Nix in Skeletal Muscle of the Aged Male Interleukin 10 Null Mouse.

Chronic inflammation is associated with muscle weakness and frailty in older adults. The antagonistic cross-talk between macrophage migration inhibitory factor (Mif), an anti-apoptotic cytokine and NIP3-like protein X (Nix), a pro-apoptotic mitochondrial protein, may play a role in mitochondrial free radical homeostasis and inflammatory myopathies. We examined Nix-Mif interaction in inflammation and aging using young and old, IL-10tm/tm (a rodent model of chronic inflammation) and C57BL/6 mice. In this study, we observed that Nix and Mif were co-localized in skeletal muscles of aged and inflamed mice. We show an inflammation- and age-related association between Nix and Mif gene expression, with the strongest positive correlation observed in old IL-10tm/tm skeletal muscles. The IL-10tm/tm skeletal muscles also had the highest levels of oxidative stress damage. These observations suggest that Nix-Mif cross-talk may play a role in the interface between chronic inflammation and oxidative stress in aging skeletal muscles.

[Rehabilitation standards for follow-up treatment and rehabilitation of patients with ventricular assist device (VAD)]. / Rehabilitationsstandards für die Anschlussheilbehandlung und allgemeine Rehabilitation von Patienten mit einem Herzunterstützungssystem (VAD - ventricular assist device).

The increasing use of ventricular assist devices (VADs) in terminal heart failure patients provides new challenges to cardiac rehabilitation physicians. Structured cardiac rehabilitation strategies are still poorly implemented for this special patient group. Clear guidance and more evidence for optimal modalities are needed. Thereby, attention has to be paid to specific aspects, such as psychological and social support and education (e.g., device management, INR self-management, drive-line care, and medication).In Germany, the post-implant treatment and rehabilitation of VAD Patients working group was founded in 2012. This working group has developed clear recommendations for the rehabilitation of VAD patients according to the available literature. All facets of VAD patients' rehabilitation are covered. The present paper is unique in Europe and represents a milestone to overcome the heterogeneity of VAD patient rehabilitation.

Differences in the ways sympathetic neurons and endocrine cells process, store, and secrete exogenous neuropeptides and peptide-processing enzymes.

Most neurons store peptides in large dense core vesicles (LDCVs) and release the neuropeptides in a regulated manner. Although LDCVs have been studied in endocrine cells, less is known about these storage organelles in neurons. In this study we use the endogenous peptide NPY (neuropeptide Y) and the endogenous peptide-processing enzyme PAM (peptidylglycine alpha-amidating monooxygenase) as tools to study the peptidergic system in cultured neurons from the superior cervical ganglion (SCG). Once mature, SCG neurons devote as much of their biosynthetic capabilities to neurotransmitter production as endocrine cells devote to hormone production. Unlike pituitary and atrium, SCG neurons cleave almost all of the bifunctional PAM protein they produce into soluble monofunctional enzymes. Very little PAM or NPY is secreted under basal conditions, and the addition of secretagogue dramatically stimulates the secretion of PAM and NPY to a similar extent. Although endocrine cells typically package "foreign" secretory products together with endogenous products, pro-opiomelanocortin- and PAM-derived products encoded by adenovirus in large part were excluded from the LDCVs of SCG neurons. When expressed in corticotrope tumor cells and primary anterior pituitary cultures, the same virally encoded products were metabolized normally. The differences that were observed could reflect differences in the properties of neuronal and endocrine peptidergic systems or differences in the ability of neurons and endocrine cells to express viral transcripts.

Complete sequence of 3'-untranslated region of Tau from rat central nervous system. Implications for mRNA heterogeneity.

Tau is a family of microtubule associated proteins, heterogeneous in molecular weights, which are expressed specifically in neurons. Tau is encoded by a single gene, while its transcript undergoes a complex and regulated alternative splicing, giving rise to several mRNA species that migrate on Northern blots at approximately 6 and 2 kb. In this report we characterize a full size transcript of tau mRNA from rat brain and demonstrate that it contains 5203 nucleotides (not including exon 2 and 3), which correlates well with the exact size of the transcript as analyzed by Northern blot using RNA standard size markers. The full length of the 3'-untranslated region contains 3848 bp and includes two polyadenylation signals which may yield the two size transcripts in the central nervous system. The first polyadenylation signal is located in the retained intron 13/14 and the second polyadenylation signal is 19 nucleotides before the poly(A) tail. Unspliced intron 13/14 was detected in all RNA preparations tested, including RNA from different ages and different regions of rat brain, RNA from dorsal root ganglia and from undifferentiated and differentiated PC12 cells. In none of the above tissues and cells was a spliced transcript lacking intron 13/14 detected.

Effect of ion exchange of glazed dental glass ceramics on strength parameters.

Ion exchange treatments can significantly increase the strength of dental glass ceramic core materials by induced compressive residual stresses. However, the core materials of dental restorations need to be veneered or at least to be stained and glazed for esthetic and functional reasons. The objective of this study was to determine the effect of different ion exchange treatments on the strength parameters of stained and glazed glass ceramics. Batches of specimens made of a leucite reinforced dental glass with and without staining and glazing layer, untreated, single ion exchanged (KNO3), and dual ion exchanged (1. KNO3/27, 2. 30 mol% NaNO3/70 mol% KNO3) were tested. The strength of the core material was increased from 117 to 213 MPa by single ion exchange. Staining and glazing increased the strength up to 165 MPa. Single ion exchange of the stained and glazed core caused only a slight additional strength increase up to 173 MPa. The dual ion exchanged stained and glazed core exhibit a strength of 195 MPa and decreased the large strength scatter because of a well-designed residual stress profile. We conclude that dual ion exchange treatments could significantly increase the mechanical reliability of stained and glazed glass ceramic restorations.

Influence of annealing temperature on the strength of dental glass ceramic materials.

OBJECTIVES: Dental glass ceramic components are always loaded by residual stresses because of the manufacturing process. For a reliable mechanical characterization, residual stress-free specimens are needed. Residual stresses can be removed by an annealing process. The hypothesis of this work was, that the annealing temperature must be individually chosen to reliably remove possible residual stresses without changing the characteristics of the glass ceramic material. METHODS: Knoop-indented specimens made of the glass ceramic materials Duceram Opaker (Degudent, Hanau, Germany, formerly Ducera, Rosbach, FRG), Empress 1 (Ivoclar Vivadent, Schaan, Liechtenstein), In-Ceram Alumina (Vita Zahnfabrik, Bad Säckingen, Germany), Optec OPC (Jeneric Pentron, Wellingford, USA), and Vita Omega Opaker (Vita Zahnfabrik, Bad Säckingen, Germany) were annealed at various temperatures below and above the respective glass transition temperature. The Weibull strength parameters and the lengths of the indentations before and after annealing were determined. RESULTS: A strength increase caused by relaxation of residual stresses was found after annealing at elevated temperatures. A local maximum of increased strength was determined after annealing at a temperature of 100K below the glass transition temperature. After annealing at temperatures above the glass transition temperature, microplasticity was observed. SIGNIFICANCE: It is recommended to anneal glass ceramic components that are intended to be mechanically characterized at a temperature 100K below the respective glass transition temperature before testing to determine 'true' mechanical values that are not influenced by possible residual stresses.

[Bone cement adhesion on ceramic surfaces - surface activation of retention surfaces of knee prostheses by atmospheric plasma versus thermal surface treatment]. / Zementhaftung auf keramischen Oberflächen - Oberflächenaktivierung der Retentionsflächen von Knieendoprothesen durch atmosphärisches Plasma vs. thermischer Oberflächenbehandlung.

AIM: CoCrMo alloys are contraindicated for allergy sufferers. For these patients, uncemented and cemented prostheses made of titanium alloy are indicated. Knee prostheses machined from that alloy, however, may have poor tribological behaviour, especially in relation to UHMWPE inlays. Therefore, for knee replacement cemented high-strength oxide ceramic prostheses are suitable for allergy sufferers and in cases of particle-induced aseptic loosening. For adhesion of bone cement, the ceramic surface, however, only exposes inefficient mechanical retention spots as compared with a textured metal surface. Undercuts generated by corundum blasting which in the short-term are highly efficient on a CoCrMo surface are not possible on a ceramic surface due to the brittleness of ceramics. Textures due to blasting may initiate cracks which will weaken the strength of a ceramic prosthesis. Due to the lack of textures mechanical retention is poor or even not existent. Micromotions are promoted and early aseptic loosening is predictable. Instead silicoating of the ceramic surface will allow specific adhesion and result in better hydrolytic stability of bonding thereby preventing early aseptic loosening. Silicoating, however, presupposes a clean and chemically active surface which can be achieved by atmospheric plasma or thermal surface treatment. METHOD: In order to evaluate the effectiveness of silicoating the bond strengths of atmospheric plasma versus thermal surface treated and silicate layered ZPTA surfaces were compared with "as-fired" surfaces by utilising TiAlV probes (diameter 6 mm) for traction-adhesive strength tests. After preparing samples for traction-adhesive strength tests (sequence: ceramic substrate, silicate and silane, protective lacquer [PolyMA], bone cement, TiAlV probe) they were aged for up to 150 days at 37 °C in Ringer's solution. RESULTS: The bond strengths observed for all ageing intervals were well above 20 MPa and much higher and more hydrolytically stable for silicate layered compared with "as-fired" ZPTA samples. CONCLUSION: Silicoating may be effective for achieving high initial bond strength of bone cement on surfaces of oxide ceramics and also suitable to stabilise bond strength under hydrolytic conditions as present in the human body in the long-term. Activation by atmospheric plasma or thermal surface treatment seems to be effective for activation prior to silicoating. Due the proposed silicate layer migration, micromotions and debonding should be widely reduced or even eliminated.

Adenovirally encoded prohormone convertase-1 functions in atrial myocyte large dense core vesicles.

Bioactive peptides are usually synthesized as inactive precursor proteins that yield bioactive products only after specific biosynthetic processing events. Large dense core vesicles (LDCV) are usually the site of storage of mature peptides. Atrial myocyte LDCV are rather unique in their storage of intact prohormone, proatrial natriuretic factor (pro-ANF), with no storage of cleaved products. To investigate whether the lack of intracellular cleavage of pro-ANF is due to the absence of prohormone convertases (PCs) from the atrial granules or to other factors, we expressed PC1 in atrial myocyte cultures using a recombinant adenovirus vector. Pro-PC1 protein was processed to mature PC1 and to the COOH-terminally shortened neuroendocrine-specific form of PC1 and rapidly secreted. Integral membrane forms of peptidylglycine alpha-amidating monooxygenase (PAM) were processed by PC1, and two primary products were secreted: a monofunctional monooxygenase and a larger bifunctional form. The cleaved PAM products were stored in LDCV, as secretion of PAM-derived products was stimulatable. In addition, pro-ANF was processed to ANF within PC1-expressing cells. In primary atrial myocytes, virally encoded PC1 is active on three substrates; lack of cleavage of pro-ANF and PAM in atrial myocytes is not due to a fundamental inability of atrial LDCV to support endoproteolytic processing.