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1.
Plant Biol (Stuttg) ; 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38924230

ABSTRACT

Plant tissue in vitro culture is increasingly used in agriculture to improve crop production, nutritional quality, and commercial value. In plant virology, the technique is used as sanitation protocol to produce virus-free plants. Sanitized (S) artichokes show increased vigour compared to their non-sanitized (NS) counterparts, because viral infections lead to a decline of growth and development. To investigate mechanisms that control the complex traits related to morphology, growth, and yield in S artichokes compared to NS plants, RNAseq analysis and phenotyping by imaging were used. The role of peroxidases (POD) was also investigated to understand their involvement in sanitized plant development. Results showed that virus infection affected regulation of cell cycle, gene expression and signal transduction modulating cellular response to stimulus/stress. Moreover, primary metabolism and photosynthesis were also influenced, contributing to explain the main morphological differences observed between S and NS artichokes. Sanitized artichokes are also characterized by higher POD activity, probably associated with increased plant growth, rather than strengthening of cell walls. Overall, results show that the differences in development of S artichokes may be derived from the in vitro culture stressor, as well as through pathogen elimination, which, in turn, improve qualitative and quantitative artichoke production.

2.
Front Bioeng Biotechnol ; 10: 867728, 2022.
Article in English | MEDLINE | ID: mdl-35662849

ABSTRACT

The impact of graphene oxide on hepatic functional cells represents a crucial evaluation step for its potential application in nanomedicine. Primary human hepatocytes are the gold standard for studying drug toxicity and metabolism; however, current technical limitations may slow down the large-scale diffusion of this cellular tool for in vitro investigations. To assess the potential hepatotoxicity of graphene oxide, we propose an alternative cell model, the second-generation upcyte® hepatocytes, which show metabolic and functional profiles akin to primary human hepatocytes. Cells were acutely exposed to sub-lethal concentrations of graphene oxide (≤80 µg/ml) for 24 h and stress-related cell responses (such as apoptosis, oxidative stress, and inflammatory response) were evaluated, along with a broad investigation of graphene oxide impact on specialized hepatic functions. Results show a mild activation of early apoptosis but not oxidative stress or inflammatory response in our cell model. Notably, while graphene oxide clearly impacted phase-I drug-metabolism enzymes (e.g., CYP3A4, CYP2C9) through the inhibition of gene expression and metabolic activity, conversely, no effect was observed for phase-II enzyme GST and phase-III efflux transporter ABCG2. The GO-induced impairment of CYP3A4 occurs concomitantly with the activation of an early acute-phase response, characterized by altered levels of gene expression and protein production of relevant acute-phase proteins (i.e., CRP, Albumin, TFR, TTR). These data suggest that graphene oxide induces an acute phase response, which is in line with recent in vivo findings. In conclusion, upcyte® hepatocytes appear a reliable in vitro model for assessing nanomaterial-induced hepatotoxicity, specifically showing that sub-lethal doses of graphene oxide have a negative impact on the specialized hepatic functions of these cells. The impairment of the cytochrome P450 system, along with the activation of an acute-phase response, may suggest potential detrimental consequences for human health, as altered detoxification from xenobiotics and drugs.

3.
Sci Rep ; 7(1): 5890, 2017 07 19.
Article in English | MEDLINE | ID: mdl-28724999

ABSTRACT

The degenerative effects of multiple sclerosis at the level of the vascular and neuronal networks in the central nervous system are currently the object of intensive investigation. Preclinical studies have demonstrated the efficacy of mesenchymal stem cell (MSC) therapy in experimental autoimmune encephalomyelitis (EAE), the animal model for multiple sclerosis, but the neuropathology of specific lesions in EAE and the effects of MSC treatment are under debate. Because conventional imaging techniques entail protocols that alter the tissues, limiting the reliability of the results, we have used non-invasive X-ray phase-contrast tomography to obtain an unprecedented direct 3D characterization of EAE lesions at micro-to-nano scales, with simultaneous imaging of the vascular and neuronal networks. We reveal EAE-mediated alterations down to the capillary network. Our findings shed light on how the disease and MSC treatment affect the tissues, and promote X-ray phase-contrast tomography as a powerful tool for studying neurovascular diseases and monitoring advanced therapies.


Subject(s)
Capillaries/diagnostic imaging , Capillaries/pathology , Multiple Sclerosis/diagnostic imaging , Multiple Sclerosis/pathology , Neurons/pathology , Tomography, X-Ray , Animals , Capillaries/ultrastructure , Disease Models, Animal , Encephalomyelitis, Autoimmune, Experimental/diagnostic imaging , Encephalomyelitis, Autoimmune, Experimental/pathology , Female , Imaging, Three-Dimensional , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/cytology , Mice, Inbred C57BL , Nanoparticles/chemistry , Nanoparticles/ultrastructure
4.
Sci Rep ; 7: 41054, 2017 01 23.
Article in English | MEDLINE | ID: mdl-28112212

ABSTRACT

The investigation of the neuronal network in mouse spinal cord models represents the basis for the research on neurodegenerative diseases. In this framework, the quantitative analysis of the single elements in different districts is a crucial task. However, conventional 3D imaging techniques do not have enough spatial resolution and contrast to allow for a quantitative investigation of the neuronal network. Exploiting the high coherence and the high flux of synchrotron sources, X-ray Phase-Contrast multiscale-Tomography allows for the 3D investigation of the neuronal microanatomy without any aggressive sample preparation or sectioning. We investigated healthy-mouse neuronal architecture by imaging the 3D distribution of the neuronal-network with a spatial resolution of 640 nm. The high quality of the obtained images enables a quantitative study of the neuronal structure on a subject-by-subject basis. We developed and applied a spatial statistical analysis on the motor neurons to obtain quantitative information on their 3D arrangement in the healthy-mice spinal cord. Then, we compared the obtained results with a mouse model of multiple sclerosis. Our approach paves the way to the creation of a "database" for the characterization of the neuronal network main features for a comparative investigation of neurodegenerative diseases and therapies.


Subject(s)
Microvessels/diagnostic imaging , Nerve Net/diagnostic imaging , Neurons/physiology , Spinal Cord/diagnostic imaging , Animals , Imaging, Three-Dimensional , Mice , Microvessels/innervation , Microvessels/physiology , Nerve Net/physiology , Spinal Cord/physiology , Synchrotrons
5.
Biomed Mater ; 11(4): 041001, 2016 08 02.
Article in English | MEDLINE | ID: mdl-27481333

ABSTRACT

In the biomedical sector the availability of engineered scaffolds and dressings that control and reduce inflammatory states is highly desired, particularly for the management of burn wounds. In this work, we demonstrate for the first time, to the best of our knowledge, that electrospun fibrous dressings of poly(octyl cyanoacrylate) (POCA) combined with polypropylene fumarate (PPF) possess anti-inflammatory activity and promote the fast and effective healing of mild skin burns in an animal model. The fibers produced had an average diameter of (0.8 ± 0.1) µm and they were able to provide a conformal coverage of the injured tissue. The application of the fibrous mats on the burned tissue effectively reduced around 80% of the levels of pro-inflammatory cytokines in the first 48 h in comparison with un-treated animals, and enhanced skin epithelialization. From histological analysis, the skin thickness of the animals treated with POCA : PPF dressings appeared similar to that of one of the naïve animals: (13.7 ± 1.4) µm and (14.3 ± 2.5) µm for naïve and treated animals, respectively. The density of dermal cells was comparable as well: (1100 ± 112) cells mm(-2) and (1358 ± 255) cells mm(-2) for naïve and treated mice, respectively. The results demonstrate the suitability of the electrospun dressings in accelerating and effectively promoting the burn healing process.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Burns/therapy , Disease Models, Animal , Fumarates/pharmacology , Nanofibers/chemistry , Polypropylenes/pharmacology , Skin Diseases/therapy , Wound Healing/drug effects , Animals , Bandages , Burns/etiology , Burns/pathology , Cyanoacrylates/chemistry , Male , Mice , Mice, Inbred C57BL , Skin Diseases/etiology , Skin Diseases/pathology , Ultraviolet Rays/adverse effects
6.
Opt Express ; 21(9): 10792-800, 2013 May 06.
Article in English | MEDLINE | ID: mdl-23669936

ABSTRACT

We report an experimental study of the spontaneous spatial and temporal coherence of polariton condensates generated in the optical parametric oscillator configuration, below and at the parametric threshold, and as a function of condensate area. Above the threshold we obtain very long coherence times (up to 3 ns) and a spatial coherence extending over the entire condensate (40 µm). The very long coherence time and its dependence on condensate area and pump power reflect the suppression of polariton-polariton interactions by an effect equivalent to motional narrowing.


Subject(s)
Amplifiers, Electronic , Oscillometry/instrumentation , Surface Plasmon Resonance/instrumentation , Equipment Design , Equipment Failure Analysis , Light , Miniaturization , Scattering, Radiation
7.
Opt Express ; 17(5): 3941-50, 2009 Mar 02.
Article in English | MEDLINE | ID: mdl-19259235

ABSTRACT

We present a detailed investigation of the different processes responsible for the optical nonlinearities of silicon nanocrystals at 1550 nm. Through z-scan measurements, the bound-electronic and excited carrier contributions to the nonlinear refraction were measured in presence of two-photon absorption. A study of the nonlinear response at different excitation powers has permitted to determine the change in the refractive index per unit of photo-excited carrier density sigma(r) and the value of the real bound-electronic nonlinear refraction n(2be) as a function of the nanocrystals size. Moreover at high excitation power, a saturation of the nonlinear absorption was observed due to band-filling effects.

8.
Soc Work ; 35(3): 228-34, 1990 May.
Article in English | MEDLINE | ID: mdl-2095751

ABSTRACT

In this article, the authors examine the evolution of America's varied and often conflicting responses to the needs of its children--more specifically, the historical responses to dependent, neglected, and emotionally disordered children. The authors discuss America's historical ambivalence about whether to institutionalize children or keep them with their families, the relationship between social work professionals and clients, and the lessons that can be learned and applied to current practice. The analysis suggests that social work challenge some of the assumptions upon which prior service and advocacy efforts have been based. The magnitude of the current service system problems warrants a family-centered advocacy stance aimed at improving community-based services. This approach could free social workers to operationalize key values of the profession.


Subject(s)
Affective Symptoms/history , Child Health Services/history , Social Work/history , Child , Child Advocacy/history , Child, Institutionalized/history , History, 19th Century , History, 20th Century , Humans , Social Work/methods , United States
9.
Soc Work Health Care ; 11(3): 25-39, 1986.
Article in English | MEDLINE | ID: mdl-3738688

ABSTRACT

This is the concluding article in a series describing the evolution of a comprehensive accountability structure in the Social Work Department at the University of Minnesota Hospitals. The accountability structure is composed of five features: management by objectives, a time-oriented management information system, a set of standardized client problem definitions, specific service standards for client problems, and a comprehensive staff performance appraisal system. Utilization of information from the system by hospital and department administration, hospital clinic directors, department staff and users outside the hospital is described, as are the various direct and indirect impacts of the system on department functioning.


Subject(s)
Hospital Departments/standards , Social Work Department, Hospital/standards , Efficiency , Goals , Hospitals, University
16.
Soc Work Health Care ; 3(2): 123-41, 1977.
Article in English | MEDLINE | ID: mdl-310581

ABSTRACT

This paper describes a social work accountability structure developed and implemented at the Social Service Department of University of Minnesota Hospitals. The structure is founded in a framework derived from Management by Objectives and is composed of the following elements: (a) a transaction-based Management Information System; (b) service definitions developed by the Southern Regional Educational Board; (c) problem identification and record keeping with Problem-Oriented Medical Records; and (d) outcome evaluation through Goal Attainment Scaling. The purpose of the structure is to monitor and document departmental activities, providing feedback reports to staff, management reports to the director, and summary reports to hospital administration. The structure is not a response to a particular set of organizational problems, but an attempt to develop a coherent operational model to guide department development, remaining responsive to future as well as current needs.


Subject(s)
Health Services Administration , Social Work/organization & administration , Costs and Cost Analysis , Goals , Health Services/economics , Hospital Departments/economics , Hospital Departments/organization & administration , Hospitals, University , Information Services , Medical Records, Problem-Oriented , Minnesota , Models, Theoretical , Social Work/economics
17.
Soc Work Health Care ; 1(3): 267-76, 1976.
Article in English | MEDLINE | ID: mdl-1019794

ABSTRACT

A Management By Objectives (MBO) system has been installed in the Social Service Department of the University of Minnesota Hospitals. MBO involves administering organizations through establishment and follow-up of goals. In order to accomodate a human service milieu two additions have been made to the usual MBO format: (a) a statement of program philosophy, and (b) a statement of essential program functions. Staff reaction to the system has been mixed, while hospital administration has been uniformly favorable. In the future the MBO system will be integrated with a management information system, and "significant others" will be surveyed to get more outside input inot the formulation of objectives. MBO meets organizational needs for effective planning, management of resources and control, while at the same time maximizing staff input into the overall operation.


Subject(s)
Hospital Administration , Hospital Departments , Social Work , Goals , Methods , Minnesota , Quality Control
18.
Soc Work Health Care ; 2(1): 33-42, 1976.
Article in English | MEDLINE | ID: mdl-1019808

ABSTRACT

The growing demand for public accountability and quality assurance mechanisms affords the social work profession an opportunity to take a more forceful hand in the shaping of the health care delivery system. This paper surveys the impact of public accountability developments on the practice of social work in the health care fields, analyzes what has been done in social work qualtiy assurance, and suggests some strategies for enlarging the scope of social work to include productive new endeavors. Emphasis is placed upon resolution of the conflict between medical and human service treatment models.


Subject(s)
Quality Control , Quality of Health Care , Social Work/standards , Delivery of Health Care , Hospitals , Humans , United States
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