Soil fungal and bacterial communities reflect differently tundra vegetation state transitions and soil physico-chemical properties.

Strong disturbances may induce ecosystem transitions into new alternative states that sustain through plant-soil interactions, such as the transition of dwarf shrub-dominated into graminoid-dominated vegetation by herbivory in tundra. Little evidence exists on soil microbial communities in alternative states, and along the slow process of ecosystem return into the predisturbance state. We analysed vegetation, soil microbial communities and activities as well as soil physico-chemical properties in historical reindeer enclosures in northernmost Finland in the following plot types: control heaths in the surrounding tundra; graminoid-dominated; 'shifting'; and recovered dwarf shrub-dominated vegetation inside enclosures. Soil fungal communities followed changes in vegetation, whereas bacterial communities were more affected by soil physico-chemical properties. Graminoid plots were characterized by moulds, pathotrophs and dark septate endophytes. Ericoid mycorrhizal and saprotrophic fungi were typical for control and recovered plots. Soil microbial communities inside the enclosures showed historical contingency, as their spatial variation was high in recovered plots despite the vegetation being more homogeneous. Self-maintaining feedback loops between plant functional types, soil microbial communities, and carbon and nutrient mineralization act effectively to stabilize alternative vegetation states, but once predisturbance vegetation reestablishes itself, soil microbial communities and physico-chemical properties return back towards their predisturbance state.

N-fertilization and disturbance exert long-lasting complex legacies on subarctic ecosystems.

Subarctic ecosystems are subjected to increasing nitrogen (N) enrichment and disturbances that induce particularly strong effects on plant communities when occurring in combination. There is little experimental evidence on the longevity of these effects. We applied N-fertilization (40 kg urea-N ha-1 year-1 for 4 years) and disturbance (removal of vegetation and organic soil layer on one occasion) in two plant communities in a subarctic forest-tundra ecotone in northern Finland. Within the first four years, N-fertilization and disturbance increased the share of deciduous dwarf shrubs and graminoids at the expense of evergreen dwarf shrubs. Individual treatments intensified the other's effect resulting in the strongest increase in graminoids under combined N-fertilization and disturbance. The re-analysis of the plant communities 15 years after cessation of N-fertilization showed an even higher share of graminoids. 18 years after disturbance, the total vascular plant abundance was still substantially lower and the share of graminoids higher. At the same point, the plant community composition was the same under disturbance as under combined N-fertilization and disturbance, indicating that multiple perturbations no longer reinforced the other's effect. Yet, complex interactions between N-fertilization and disturbance were still detected in the soil. We found higher organic N under disturbance and lower microbial N under combined N-fertilization and disturbance, which suggests a lower bioavailability of N sources for soil microorganisms. Our findings support that the effects of enhanced nutrients and disturbance on subarctic vegetation persist over decadal timescales. However, they also highlight the complexity of plant-soil interactions that drive subarctic ecosystem responses to multiple perturbations across varying timescales.

Experiences of people with memory disorders and their spouse carers on influencing formal care: "They ask my wife questions that they should ask me".

BACKGROUND: People with memory disorders often need care and help from family carers and health and social care providers. Due to the deterioration of cognitive capacity and language skills, they may be unable to convey their thoughts and care preferences to other people. As a result, their agency may become restricted. We investigated the descriptions provided by people with memory disorders and spousal carers of their influence on care in encounters with formal care providers. METHODS: Qualitative thematic analysis was used to identify, analyze, and report themes that describe encounters with professionals in different social or healthcare environments. In-depth interview data were gathered from 19 spouse carers and 15 persons with memory disorders. FINDINGS: Three themes out of four describe how people with memory disorders and their spouse carers influence formal care: Acquiescence, negotiating care decisions, and taking control. The fourth theme describes lack of influence. People with memory disorders and their spouse carers have ways to influence care, but spouse carers identified more ways of doing so. Both either accepted and followed the care guidelines by the formal carers or took control of the situation and made their own decisions. Spouse carers also sought to influence care decisions through negotiations with formal carers. When formal carers' decisions were experienced as inconsistent or the rationale of their actions difficult to follow, the possibilities to influence care were limited. CONCLUSIONS: People with memory disorders and their family carers are often in a disadvantaged position as they lack power over the health and social care decision-making during the illness, which is often guided by structural factors. To support the agency of people with memory disorders and to promote shared decision-making, clarification of the service structure and clearer communication between the different parties involved in care are required.

Serum Thymidine Kinase 1, Canine-C-Reactive Protein, Haptoglobin, and Vitamin D Concentrations in Dogs with Immune-Mediated Hemolytic Anemia, Thrombocytopenia, and Polyarthropathy.

BACKGROUND: Relapses of immune-mediated hemolytic anemia (IMHA), thrombocytopenia (ITP), or polyarthropathy (IMPA) occur despite normal hematologic and cytologic parameters. Thymidine kinase 1 (TK1), canine C-reactive protein (c-CRP), haptoglobin (HPT), and 25-Hydroxyvitamin-D (25(OH)D) might be adjunct to current monitoring strategies. HYPOTHESIS/OBJECTIVES: Compare serum concentrations of TK1, c-CRP, HPT, and 25(OH)D in dogs with well- and poorly controlled primary IMHA, ITP, or IMPA. ANIMALS: Thirty-eight client-owned dogs. METHODS: Prospective descriptive study. Dogs diagnosed with IMHA, ITP, or IMPA had serum biomarker concentrations measured commercially. Disease control was assessed by hematocrit/PCV and reticulocyte count, platelet count, and synovial fluid cytology for IMHA, ITP, and IMPA, respectively. Statistical analysis performed by Mann-Whitney rank-sum tests and receiver operating characteristic curves. RESULTS: TK1 and c-CRP, but not HPT significantly decreased with well- versus poorly controlled IMHA (P = 0.047, P = 0.028, P = 0.37). C-CRP, but not TK or HPT was significantly lower with well- versus poorly controlled IMPA (P = 0.05, P = 0.28, P = 0.84). Sensitivity and specificity of TK and c-CRP (simultaneously) for detecting dogs with poorly controlled IMHA were 88 and 100%, respectively. Sensitivity and specificity of c-CRP for detecting poorly controlled dogs with IMPA were 13 and 100%, respectively. 92% of dogs were vitamin D insufficient (<100 ng/mL) regardless of disease control. CONCLUSIONS AND CLINICAL IMPORTANCE: Combining TK1 and c-CRP might act markers of disease control in dogs with IMHA. Canine-CRP cannot be recommended as an independent marker of disease control in IMPA. 25(OH)D insufficiency in immune-mediated disorders might benefit from further study to determine if supplementation could improve therapeutic response or reduce disease risk.

Generation of Functional Neuromuscular Junctions from Human Pluripotent Stem Cell Lines.

Several neuromuscular diseases involve dysfunction of neuromuscular junctions (NMJs), yet there are no patient-specific human models for electrophysiological characterization of NMJ. We seeded cells of neurally-induced embryoid body-like spheres derived from induced pluripotent stem cell (iPSC) or embryonic stem cell (ESC) lines as monolayers without basic fibroblast factor (bFGF) and observed differentiation of neuronal as well as spontaneously contracting, multinucleated skeletal myotubes. The myotubes showed striation, immunoreactivity for myosin heavy chain, actin bundles typical for myo-oriented cells, and generated spontaneous and evoked action potentials (APs). The myogenic differentiation was associated with expression of MyoD1, myogenin and type I ryanodine receptor. Neurons formed end plate like structures with strong binding of α-bungarotoxin, a marker of nicotinic acetylcholine receptors highly expressed in the postsynaptic membrane of NMJs, and expressed SMI-32, a motoneuron marker, as well as SV2, a marker for synapses. Pharmacological stimulation of cholinergic receptors resulted in strong depolarization of myotube membrane and raised Ca(2+) concentration in sarcoplasm, while electrical stimulation evoked Ca(2+) transients in myotubes. Stimulation of motoneurons with N-Methyl-D-aspartate resulted in reproducible APs in myotubes and end plates displayed typical mEPPs and tonic activity depolarizing myotubes of about 10 mV. We conclude that simultaneous differentiation of neurons and myotubes from patient-specific iPSCs or ESCs results also in the development of functional NMJs. Our human model of NMJ may serve as an important tool to investigate normal development, mechanisms of diseases and novel drug targets involving NMJ dysfunction and degeneration.

Somatic progenitor cell vulnerability to mitochondrial DNA mutagenesis underlies progeroid phenotypes in Polg mutator mice.

Somatic stem cell (SSC) dysfunction is typical for different progeroid phenotypes in mice with genomic DNA repair defects. MtDNA mutagenesis in mice with defective Polg exonuclease activity also leads to progeroid symptoms, by an unknown mechanism. We found that Polg-Mutator mice had neural (NSC) and hematopoietic progenitor (HPC) dysfunction already from embryogenesis. NSC self-renewal was decreased in vitro, and quiescent NSC amounts were reduced in vivo. HPCs showed abnormal lineage differentiation leading to anemia and lymphopenia. N-acetyl-L-cysteine treatment rescued both NSC and HPC abnormalities, suggesting that subtle ROS/redox changes, induced by mtDNA mutagenesis, modulate SSC function. Our results show that mtDNA mutagenesis affected SSC function early but manifested as respiratory chain deficiency in nondividing tissues in old age. Deletor mice, having mtDNA deletions in postmitotic cells and no progeria, had normal SSCs. We propose that SSC compartment is sensitive to mtDNA mutagenesis, and that mitochondrial dysfunction in SSCs can underlie progeroid manifestations.

Evaluation of polymerization shrinkage and hydroscopic expansion of fiber-reinforced biocomposites using optical fiber Bragg grating sensors.

OBJECTIVES: Polymerization shrinkage of dental composite materials is recognized as one of the main reasons for the development of marginal leakage between a tooth and filling material. In addition, hydroscopic expansion due to water sorption is known to cause instability in dental materials. Several methods have been proposed to quantify the polymerization shrinkage and hydroscopic expansion. However, in the case of anisotropic materials, such as unidirectional fiber-reinforced composites (FRCs), the measurement method must allow for the discrimination of the shrinkage or expansion in the two orthogonal directions. In this work, optical fiber sensors were employed to study strains in dental materials induced by polymerization shrinkage and hydroscopic expansion. METHODS: Four dental materials were evaluated in this study: unfilled BisGMA/TEGDMA-based resin, Z250 dental restorative composite, unidirectional and bidirectional fiber reinforced composites. The changes in the linear strain due to the polymerization shrinkage and hydroscopic expansion were monitored in real-time using embedded optical fiber Bragg grating (FBG) sensors. The polymerization shrinkage was monitored during the light curing process. FBG sensors were also used to record the hydroscopic expansion of the samples which were immersed in water up to 132 days. RESULTS: Unfilled polymer resin had the highest polymerization shrinkage of 0.84%. Unidirectional FRC had a relatively high shrinkage in the transverse direction with respect to the reinforcing fibers (0.41%) whereas the shrinkage along the reinforcing fibers was small (0.02%). Bidirectional FRC showed a low shrinkage value (0.03%). For most tested materials the hydroscopic expansion seemed to compensate for the polymerization shrinkage. SIGNIFICANCE: Fiber Bragg grating sensors are suitable for accurate real-time monitoring of small internal strains of biomaterials, e.g., due to polymerization shrinkage and hydroscopic expansion. Detailed data on polymerization shrinkage and water sorption behavior of different dental materials can be used to optimize the mechanical properties of dental composite materials and to improve the longevity of a dental restoration.

An introduction to music and sound approaches for health professionals: overview of an undergraduate web-based nursing course.

Nursing educators have been constantly striving to develop a curriculum which enhances holistic patient care. In this article, a descriptive overview is given of a senior level, 3 credit, nursing course designed to provide nurses and other health professionals with a background in the uses of music and the importance of auditory environments for patient care and well-being. This course, which was developed by LeNavenec and Epstein, has been available via the internet since Spring 2003.

[New serum markers to monitor treatment of acute exacerbation of interstitial lung disease].

A 58-year-old woman was admitted to our hospital because of recurrent fever, severe cough and sputum. Chest radiological examinations showed diffuse reticulonodular opacities in both lung fields. Interstitial pneumonia with probable polymyositis was diagnosed. Serum surfactant protein (SP)-A, SP-D and KL-6, which are new interstitial lung disease markers, showed values significantly higher than cutoff levels. The markers increased more in parallel with the rapid development of respiratory insufficiency, CPK level, myalgia and proximal muscle weakness. Treatment with a high dose of corticosteroid and the following gradual decrease over 8 months led to clinical and radiological improvement, with normalization of values of the markers. These markers may therefore be reliable indicators of therapeutic success. However, these markers underwent different respective changes during the first 2 months. SP-A reached a maximum at the start of the treatment, while SP-D and KL-6 peaked at 5 and 10 days, respectively, after the treatment was initiated. This discrepancy demonstrates that the markers reach the bloodstream by diverse mechanisms and are useful for analyzing pathophysiological alterations in the lung in the early stages of treatment.

Atrial natriuretic polypeptide (ANP) as protective agent of renal ischemia.

The effect of atrial natriuretic polypeptide (ANP) on hemodynamics and renal function was evaluated after the reconstructive surgery of the left renal artery in a patient with renovascular hypertension secondary to Takayasu's arteritis. The reconstructive surgery was done using the femoral artery, since we were unable to obtain adequate vein segments to fit the renal artery. The femoral artery was reconstructed by her saphenous vein segments. After 30 min of the aortorenal bypass operation, alpha-human ANP (alpha-hANP) was infused intravenously for 10 min at a rate of 0.1 microgram/kg/min. Although total peripheral resistance was decreased by alpha-hANP infusion, blood pressure was not changed because of the increased cardiac output. Glomerular filtration rate was increased markedly with concomitant increase in urine volume and urinary excretions of sodium, potassium and phosphate. Fractional excretions of water and sodium were not changed, but fractional excretion of phosphate and potassium clearance were increased. Thus, the infusion of alpha-hANP markedly improved the renal function of the ischemic kidney by the reconstructive surgery of the renal artery, suggesting that alpha-hANP seems clinically applicable as a protective agent in renal ischemia at renovascular surgery as well as the renal transplantation.