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1.
Front Immunol ; 15: 1293723, 2024.
Article in English | MEDLINE | ID: mdl-38690263

ABSTRACT

T cells must adapt to variations in tissue microenvironments; these adaptations include the degree of oxygen availability. The hypoxia-inducible factor (HIF) transcription factors control much of this adaptation, and thus regulate many aspects of T cell activation and function. The HIFs are in turn regulated by oxygen-dependent hydroxylases: both the prolyl hydroxylases (PHDs) which interact with the VHL tumour suppressor and control HIF turnover, and the asparaginyl hydroxylase known as the Factor inhibiting HIF (FIH), which modulates HIF transcriptional activity. To determine the role of this latter factor in T cell function, we generated T cell-specific FIH knockout mice. We found that FIH regulates T cell fate and function in a HIF-dependent manner and show that the effects of FIH activity occur predominantly at physiological oxygen concentrations. T cell-specific loss of FIH boosts T cell cytotoxicity, augments T cell expansion in vivo, and improves anti-tumour immunotherapy in mice. Specifically inhibiting FIH in T cells may therefore represent a promising strategy for cancer immunotherapy.


Subject(s)
Cell Differentiation , Mice, Knockout , Animals , Mice , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Repressor Proteins/genetics , Repressor Proteins/metabolism , Lymphocyte Activation/immunology , Mixed Function Oxygenases/genetics , Mixed Function Oxygenases/metabolism , Neoplasms/immunology , Neoplasms/metabolism , Mice, Inbred C57BL
2.
Life (Basel) ; 13(12)2023 Nov 23.
Article in English | MEDLINE | ID: mdl-38137850

ABSTRACT

Feline core vaccines strongly recommended for all cats are against Feline panleukopenia virus (FPV), Felid herpesvirus type 1 (FeHV-1), and Feline calicivirus (FCV), but cats can be classified as low- and high-risk based on their lifestyle. The aim of this study was to determine the actual seroprotection against FPV, FeHV-1, and FCV in a large cohort of Italian cats by using the VacciCheck test. A total of 740 cats (567 owned and 173 stray cats; 435 vaccinated and 305 unvaccinated) were analyzed for Protective Antibody Titers (PATs). Differences related to origin, sex, age, breed, FIV/FeLV status, health status, and time elapsed since last vaccination were evaluated. Less than half of the entire cohort (36.4%) had PATs for all three diseases simultaneously, increasing to 48.6% if weak positive values were also considered and 50.3% when considering only the 435 vaccinated cats. Particularly, antibodies were detected against FCV, FPV, and FeHV-1 at protective titers (PATs) in 78.6%, 68.1, and 49.1% of the cats, respectively. In general, owned, neutered, and adult FIV- and/or FeLV-negative cats were the most protected categories, even if not always for the three viruses. Most cats maintained high PATs for 3 years or longer after vaccination against FPV and FCV but not FeHV-1. Long-lasting protective immunity persisted for many years after the last vaccination (more than 18 years in the oldest cats). Nevertheless, since not all cats were protected after so many years and for all pathogens, checking protection via antibody titration could be the best choice to prevent immunity breakdowns. The discussion also focuses on the reliability of antibody titration for the two URTD (upper respiratory tract disease) viruses which, unlike for FPV, is not widely accepted as a valid index of protection.

3.
Cell Rep ; 42(9): 113013, 2023 09 26.
Article in English | MEDLINE | ID: mdl-37632752

ABSTRACT

2-Hydroxyglutarate (2HG) is a byproduct of the tricarboxylic acid (TCA) cycle and is readily detected in the tissues of healthy individuals. 2HG is found in two enantiomeric forms: S-2HG and R-2HG. Here, we investigate the differential roles of these two enantiomers in cluster of differentiation (CD)8+ T cell biology, where we find they have highly divergent effects on proliferation, differentiation, and T cell function. We show here an analysis of structural determinants that likely underlie these differential effects on specific α-ketoglutarate (αKG)-dependent enzymes. Treatment of CD8+ T cells with exogenous S-2HG, but not R-2HG, increased CD8+ T cell fitness in vivo and enhanced anti-tumor activity. These data show that S-2HG and R-2HG should be considered as two distinct and important actors in the regulation of T cell function.


Subject(s)
Neoplasms , T-Lymphocytes, Cytotoxic , Humans , T-Lymphocytes, Cytotoxic/metabolism , CD8-Positive T-Lymphocytes/metabolism , Glutarates/metabolism , Neoplasms/metabolism , Isocitrate Dehydrogenase
4.
Nat Metab ; 5(10): 1747-1764, 2023 10.
Article in English | MEDLINE | ID: mdl-37605057

ABSTRACT

T cell function and fate can be influenced by several metabolites: in some cases, acting through enzymatic inhibition of α-ketoglutarate-dependent dioxygenases, in others, through post-translational modification of lysines in important targets. We show here that glutarate, a product of amino acid catabolism, has the capacity to do both, and has potent effects on T cell function and differentiation. We found that glutarate exerts those effects both through α-ketoglutarate-dependent dioxygenase inhibition, and through direct regulation of T cell metabolism via glutarylation of the pyruvate dehydrogenase E2 subunit. Administration of diethyl glutarate, a cell-permeable form of glutarate, alters CD8+ T cell differentiation and increases cytotoxicity against target cells. In vivo administration of the compound is correlated with increased levels of both peripheral and intratumoural cytotoxic CD8+ T cells. These results demonstrate that glutarate is an important regulator of T cell metabolism and differentiation with a potential role in the improvement of T cell immunotherapy.


Subject(s)
Biochemical Phenomena , CD8-Positive T-Lymphocytes , CD8-Positive T-Lymphocytes/metabolism , Glutarates/metabolism
5.
Elife ; 122023 05 11.
Article in English | MEDLINE | ID: mdl-37166103

ABSTRACT

Oxygenation levels are a determinative factor in T cell function. Here, we describe how oxygen tensions sensed by mouse and human T cells at the moment of activation act to persistently modulate both differentiation and function. We found that in a protocol of CAR-T cell generation, 24 hr of low oxygen levels during initial CD8+ T cell priming is sufficient to enhance antitumour cytotoxicity in a preclinical model. This is the case even when CAR-T cells are subsequently cultured under high oxygen tensions prior to adoptive transfer. Increased hypoxia-inducible transcription factor (HIF) expression was able to alter T cell fate in a similar manner to exposure to low oxygen tensions; however, only a controlled or temporary increase in HIF signalling was able to consistently improve cytotoxic function of T cells. These data show that oxygenation levels during and immediately after T cell activation play an essential role in regulating T cell function.


Subject(s)
CD8-Positive T-Lymphocytes , Oxygen , Mice , Humans , Animals , Oxygen/metabolism , Signal Transduction , Lymphocyte Activation , Adoptive Transfer
6.
Trials ; 24(1): 354, 2023 May 25.
Article in English | MEDLINE | ID: mdl-37231429

ABSTRACT

BACKGROUND: In the Lake Victoria Basin of western Kenya, malaria remains highly endemic despite high coverage of interventions such as insecticide-impregnated long-lasting insecticidal nets (LLIN). The malaria-protective effect of LLINs is hampered by insecticide resistance in Anopheles vectors and its repurposing by the community. Ceiling nets and LLIN with synergist piperonyl butoxide (PBO-LLIN) are novel tools that can overcome the problems of behavioral variation of net use and metabolic resistance to insecticide, respectively. The two have been shown to reduce malaria prevalence when used independently. Integration of these two tools (i.e., ceiling nets made with PBO-LLIN or Olyset®Plus ceiling nets) appears promising in further reducing the malaria burden. METHODS: A cluster-randomized controlled trial is designed to assess the effect of Olyset®Plus ceiling nets on reducing malaria prevalence in children on Mfangano Island in Homa Bay County, where malaria transmission is moderate. Olyset®Plus ceiling nets will be installed in 1315 residential structures. Malaria parasitological, entomological, and serological indicators will be measured for 12 months to compare the effectiveness of this new intervention against conventional LLIN in the control arm. DISCUSSION: Wider adoption of Olyset®Plus ceiling nets to complement existing interventions may benefit other malaria-endemic counties and be incorporated as part of Kenya's national malaria elimination strategy. TRIAL REGISTRATION: UMIN Clinical Trials Registry UMIN000045079. Registered on 4 August 2021.


Subject(s)
Insecticide-Treated Bednets , Insecticides , Malaria , Animals , Child , Humans , Insecticides/pharmacology , Kenya/epidemiology , Lakes , Prevalence , Mosquito Vectors , Insecticide Resistance , Malaria/epidemiology , Malaria/prevention & control , Mosquito Control/methods , Randomized Controlled Trials as Topic
7.
Front Immunol ; 14: 1101433, 2023.
Article in English | MEDLINE | ID: mdl-36923405

ABSTRACT

Introduction: CD8+ T cells infiltrate virtually every tissue to find and destroy infected or mutated cells. They often traverse varying oxygen levels and nutrient-deprived microenvironments. High glycolytic activity in local tissues can result in significant exposure of cytotoxic T cells to the lactate metabolite. Lactate has been known to act as an immunosuppressor, at least in part due to its association with tissue acidosis. Methods: To dissect the role of the lactate anion, independently of pH, we performed phenotypical and metabolic assays, high-throughput RNA sequencing, and mass spectrometry, on primary cultures of murine or human CD8+ T cells exposed to high doses of pH-neutral sodium lactate. Results: The lactate anion is well tolerated by CD8+ T cells in pH neutral conditions. We describe how lactate is taken up by activated CD8+ T cells and can displace glucose as a carbon source. Activation in the presence of sodium lactate significantly alters the CD8+ T cell transcriptome, including the expression key effector differentiation markers such as granzyme B and interferon-gamma. Discussion: Our studies reveal novel metabolic features of lactate utilization by activated CD8+ T cells, and highlight the importance of lactate in shaping the differentiation and activity of cytotoxic T cells.


Subject(s)
Lactic Acid , Transcriptome , Mice , Humans , Animals , Lactic Acid/metabolism , Sodium Lactate/metabolism , CD8-Positive T-Lymphocytes/metabolism , T-Lymphocytes, Cytotoxic/metabolism
8.
Life (Basel) ; 13(2)2023 Feb 20.
Article in English | MEDLINE | ID: mdl-36836944

ABSTRACT

Canine vaccination is the main tool for preventing dangerous and widespread diseases. The strongly recommended (core) dog vaccines are against Canine Parvovirus type 2 (CPV-2), Canine Distemper Virus (CDV), and Canine Adenovirus (CAdV-1), but vaccination protocols should be tailored to dog lifestyles. Vaccination guidelines suggest vaccinating adult dogs no more frequently than every 3 years using modified live (attenuated) vaccines (MLV), thus obtaining a long-lasting (sometimes throughout life) specific protection in many but not all animals. The aim of this study was to determine the actual levels of seroprotection against CPV-2, CDV and CAdV-1 in a cohort of Italian dogs by using the in-practice test VacciCheck. A total of 1,027 dogs (951 vaccinated and 76 unvaccinated) were analyzed for Protective Antibody Titers (PATs) against CPV-2, CDV, and CAdV-1. Differences related to sex, age, breed size, health status, and time elapsed since last vaccination were evaluated. Half of the entire canine cohort (50.6%) had PATs for all three viruses (68.5% considering only vaccinated dogs). In particular, 90.8% of dogs were protected against CPV-2, 68.6% against CDV, and 79.8% against CAdV-1. Most dogs remained protected for 3 years after vaccination or longer. Revaccination on a 3-year basis can then be recommended for core MLV vaccines without altering individual's seroprotection or even herd immunity.

9.
Cancer Immunol Res ; 11(3): 351-363, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36574610

ABSTRACT

Nitric oxide (NO) is a signaling molecule produced by NO synthases (NOS1-3) to control processes such as neurotransmission, vascular permeability, and immune function. Although myeloid cell-derived NO has been shown to suppress T-cell responses, the role of NO synthesis in T cells themselves is not well understood. Here, we showed that significant amounts of NO were synthesized in human and murine CD8+ T cells following activation. Tumor growth was significantly accelerated in a T cell-specific, Nos2-null mouse model. Genetic deletion of Nos2 expression in murine T cells altered effector differentiation, reduced tumor infiltration, and inhibited recall responses and adoptive cell transfer function. These data show that endogenous NO production plays a critical role in T cell-mediated tumor immunity.


Subject(s)
Neoplasms , Nitric Oxide , Animals , Mice , Humans , Nitric Oxide Synthase Type II/genetics , Mice, Knockout , Neoplasms/genetics , CD8-Positive T-Lymphocytes
10.
Front Immunol ; 13: 837669, 2022.
Article in English | MEDLINE | ID: mdl-35251031

ABSTRACT

Targeting T cell metabolism is an established method of immunomodulation. Following activation, T cells engage distinct metabolic programs leading to the uptake and processing of nutrients that determine cell proliferation and differentiation. Redirection of T cell fate by modulation of these metabolic programs has been shown to boost or suppress immune responses in vitro and in vivo. Using publicly available T cell transcriptomic and proteomic datasets we identified vitamin B6-dependent transaminases as key metabolic enzymes driving T cell activation and differentiation. Inhibition of vitamin B6 metabolism using the pyridoxal 5'-phosphate (PLP) inhibitor, aminoxyacetic acid (AOA), suppresses CD8+ T cell proliferation and effector differentiation in a dose-dependent manner. We show that pyridoxal phosphate phosphatase (PDXP), a negative regulator of intracellular vitamin B6 levels, is under the control of the hypoxia-inducible transcription factor (HIF1), a central driver of T cell metabolism. Furthermore, by adoptive transfer of CD8 T cells into a C57BL/6 mouse melanoma model, we demonstrate the requirement for vitamin B6-dependent enzyme activity in mediating effective anti-tumor responses. Our findings show that vitamin B6 metabolism is required for CD8+ T cell proliferation and effector differentiation in vitro and in vivo. Targeting vitamin B6 metabolism may therefore serve as an immunodulatory strategy to improve anti-tumor immunotherapy.


Subject(s)
CD8-Positive T-Lymphocytes , Neoplasms , Vitamin B 6 , Aminooxyacetic Acid/pharmacology , Animals , CD8-Positive T-Lymphocytes/immunology , Hypoxia-Inducible Factor 1, alpha Subunit , Melanoma/immunology , Mice , Mice, Inbred C57BL , Neoplasms/immunology , Phosphoprotein Phosphatases , Proteomics , Pyridoxal Phosphate/antagonists & inhibitors , Vitamin B 6/metabolism
11.
Front Immunol ; 12: 633586, 2021.
Article in English | MEDLINE | ID: mdl-34054802

ABSTRACT

Myeloid cell interactions with cells of the adaptive immune system are an essential aspect of immunity. A key aspect of that interrelationship is its modulation by the microenvironment. Oxygen is known to influence myelosuppression of T cell activation in part via the Hypoxia inducible (HIF) transcription factors. A number of drugs that act on the HIF pathway are currently in clinical use and it is important to evaluate how they act on immune cell function as part of a better understanding of how they will influence patient outcomes. We show here that increased activation of the HIF pathway, either through deletion of the negative regulator of HIF, the von Hippel-Lindau (VHL) gene, in myeloid cells, or through pharmacological inhibitors of VHL-mediated degradation of HIF, potently suppresses T cell proliferation in myeloid cell/T cell culture. These data demonstrate that both pharmacological and genetic activation of HIF in myeloid cells can suppress adaptive cell immune response.


Subject(s)
CD8-Positive T-Lymphocytes/drug effects , Cell Proliferation/drug effects , Glycine/analogs & derivatives , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Isoquinolines/pharmacology , Macrophages/drug effects , Oxygen/metabolism , Adaptive Immunity , Animals , CD8-Positive T-Lymphocytes/physiology , Cell Hypoxia/drug effects , Cell Line, Tumor , Coculture Techniques , Glycine/pharmacology , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/antagonists & inhibitors , Mice , Mice, Transgenic , Oxygen/pharmacology , Von Hippel-Lindau Tumor Suppressor Protein/genetics
12.
Elife ; 92020 10 23.
Article in English | MEDLINE | ID: mdl-33095157

ABSTRACT

Exercise has a wide range of systemic effects. In animal models, repeated exertion reduces malignant tumor progression, and clinically, exercise can improve outcome for cancer patients. The etiology of the effects of exercise on tumor progression are unclear, as are the cellular actors involved. We show here that in mice, exercise-induced reduction in tumor growth is dependent on CD8+ T cells, and that metabolites produced in skeletal muscle and excreted into plasma at high levels during exertion in both mice and humans enhance the effector profile of CD8+ T-cells. We found that activated murine CD8+ T cells alter their central carbon metabolism in response to exertion in vivo, and that immune cells from trained mice are more potent antitumor effector cells when transferred into tumor-bearing untrained animals. These data demonstrate that CD8+ T cells are metabolically altered by exercise in a manner that acts to improve their antitumoral efficacy.


Exercise affects almost all tissues in the body, and scientists have found that being physically active can reduce the risk of several types of cancer as well as improving outcomes for cancer patients. However, it is still unknown how exercise exerts its protective effects. One of the hallmarks of cancer is the ability of cancer cells to evade detection by the immune system, which can in some cases stop the body from eliminating tumor cells. Rundqvist et al. used mice to investigate how exercise helps the immune system act against tumor progression. They found that when mice exercised, tumor growth was reduced, and this decrease in growth depended on the levels of a specific type of immune cell, the CD8+ T cell, circulating in the blood. Additionally, Rundqvist et al. found that CD8+ T cells were made more effective by molecules that muscles released into the blood during exercise. Isolating immune cells after intense exercise showed that these super-effective CD8+ T cells alter how they use molecules for energy production after exertion. Next, immune cells from mice that had exercised frequently were transferred into mice that had not exercised, where they were more effective against tumor cells than the immune cells from untrained mice. These results demonstrate that CD8+ T cells are altered by exercise to improve their effectiveness against tumors. The ability of T cells to identify and eliminate cancer cells is essential to avoid tumor growth, and is one of the foundations of current immune therapy treatments. Exercise could improve the outcome of these treatments by increasing the activation of the immune system, making tumor-fighting cells more effective.


Subject(s)
Carcinogenesis , Physical Conditioning, Animal , T-Lymphocytes, Cytotoxic/physiology , Animals , Cell Line, Tumor , Female , Mice
13.
Blood Adv ; 4(18): 4483-4493, 2020 09 22.
Article in English | MEDLINE | ID: mdl-32941648

ABSTRACT

Cancer immunotherapy is advancing rapidly and gene-modified T cells expressing chimeric antigen receptors (CARs) show particular promise. A challenge of CAR-T cell therapy is that the ex vivo-generated CAR-T cells become exhausted during expansion in culture, and do not persist when transferred back to patients. It has become clear that naive and memory CD8 T cells perform better than the total CD8 T-cell populations in CAR-T immunotherapy because of better expansion, antitumor activity, and persistence, which are necessary features for therapeutic success and prevention of disease relapse. However, memory CAR-T cells are rarely used in the clinic due to generation challenges. We previously reported that mouse CD8 T cells cultured with the S enantiomer of the immunometabolite 2-hydroxyglutarate (S-2HG) exhibit enhanced antitumor activity. Here, we show that clinical-grade human donor CAR-T cells can be generated from naive precursors after culture with S-2HG. S-2HG-treated CAR-T cells establish long-term memory cells in vivo and show superior antitumor responses when compared with CAR-T cells generated with standard clinical protocols. This study provides the basis for a phase 1 clinical trial evaluating the activity of S-2HG-treated CD19-CAR-T cells in patients with B-cell malignancies.


Subject(s)
Receptors, Antigen, T-Cell , Receptors, Chimeric Antigen , Animals , CD8-Positive T-Lymphocytes , Glutarates , Humans , Immunotherapy, Adoptive , Mice , Receptors, Antigen, T-Cell/genetics , Receptors, Chimeric Antigen/genetics
14.
Cell Death Dis ; 10(11): 857, 2019 11 12.
Article in English | MEDLINE | ID: mdl-31719530

ABSTRACT

Parkinson's disease (PD), the second most common neurodegenerative disorder, is characterized by dopaminergic neuronal loss that initiates in the substantia nigra pars compacta and by the formation of intracellular inclusions mainly constituted by aberrant α-synuclein (α-syn) deposits known as Lewy bodies. Most cases of PD are sporadic, but about 10% are familial, among them those caused by mutations in SNCA gene have an autosomal dominant transmission. SNCA encodes α-syn, a small 140-amino acids protein that, under physiological conditions, is mainly localized at the presynaptic terminals. It is prevalently cytosolic, but its presence has been reported in the nucleus, in the mitochondria and, more recently, in the mitochondria-associated ER membranes (MAMs). Whether different cellular localizations may reflect specific α-syn activities is presently unclear and its action at mitochondrial level is still a matter of debate. Mounting evidence supports a role for α-syn in several mitochondria-derived activities, among which maintenance of mitochondrial morphology and modulation of complex I and ATP synthase activity. α-syn has been proposed to localize at the outer membrane (OMM), in the intermembrane space (IMS), at the inner membrane (IMM) and in the mitochondrial matrix, but a clear and comparative analysis of the sub-mitochondrial localization of WT and mutant α-syn is missing. Furthermore, the reasons for this spread sub-mitochondrial localization under physiological and pathological circumstances remain elusive. In this context, we decided to selectively monitor the sub-mitochondrial distribution of the WT and PD-related α-syn mutants A53T and A30P by taking advantage from a bimolecular fluorescence complementation (BiFC) approach. We also investigated whether cell stress could trigger α-syn translocation within the different mitochondrial sub-compartments and whether PD-related mutations could impinge on it. Interestingly, the artificial targeting of α-syn WT (but not of the mutants) to the mitochondrial matrix impacts on ATP production, suggesting a potential role within this compartment.


Subject(s)
Dopaminergic Neurons/metabolism , Mitochondria/genetics , Parkinson Disease/metabolism , alpha-Synuclein/genetics , Adenosine Triphosphate/biosynthesis , Adenosine Triphosphate/genetics , Cytosol/metabolism , Cytosol/pathology , Dopamine/genetics , Dopamine/metabolism , Dopaminergic Neurons/pathology , Gene Expression/genetics , Humans , Mitochondria/metabolism , Mitochondria/pathology , Mitochondrial Proton-Translocating ATPases/genetics , Mitochondrial Proton-Translocating ATPases/metabolism , Mutant Proteins/genetics , Parkinson Disease/pathology , Pars Compacta/metabolism , Pars Compacta/pathology , Presynaptic Terminals/metabolism
15.
Sci Transl Med ; 9(416)2017 Nov 15.
Article in English | MEDLINE | ID: mdl-29141887

ABSTRACT

The immunosuppressive activity of mesenchymal stromal cells (MSCs) is well documented. However, the therapeutic benefit is completely unpredictable, thus raising concerns about MSC efficacy. One of the affecting factors is the unresolved conundrum that, despite being immunosuppressive, MSCs are undetectable after administration. Therefore, understanding the fate of infused MSCs could help predict clinical responses. Using a murine model of graft-versus-host disease (GvHD), we demonstrate that MSCs are actively induced to undergo perforin-dependent apoptosis by recipient cytotoxic cells and that this process is essential to initiate MSC-induced immunosuppression. When examining patients with GvHD who received MSCs, we found a striking parallel, whereby only those with high cytotoxic activity against MSCs responded to MSC infusion, whereas those with low activity did not. The need for recipient cytotoxic cell activity could be replaced by the infusion of apoptotic MSCs generated ex vivo. After infusion, recipient phagocytes engulf apoptotic MSCs and produce indoleamine 2,3-dioxygenase, which is ultimately necessary for effecting immunosuppression. Therefore, we propose the innovative concept that patients should be stratified for MSC treatment according to their ability to kill MSCs or that all patients could be treated with ex vivo apoptotic MSCs.


Subject(s)
Apoptosis/physiology , Mesenchymal Stem Cells/cytology , Animals , Graft vs Host Disease/metabolism , Graft vs Host Disease/physiopathology , Humans , Immunomodulation/genetics , Immunomodulation/physiology , Immunosuppression Therapy/methods , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/physiology
16.
Langmuir ; 23(4): 1723-34, 2007 Feb 13.
Article in English | MEDLINE | ID: mdl-17279650

ABSTRACT

Superhydrophobicity is obtained on photolithographically structured silicon surfaces consisting of flat-top pillars after a perfluorosilanization treatment. Systematic static contact angle measurements were carried out on these surfaces as a function of pillar parameters that geometrically determine the surface roughness, including pillar height, diameter, top perimeter, overall filling factor, and disposition. In line with thermodynamics models, two regimes of static contact angles are observed varying each parameter independently: the "Cassie" regime, in which the water drop sits suspended on top of the pillars (referred to as composite), corresponding to experimental contact angles greater than 140-150 degrees, and the "Wenzel" regime, in which water completely wets the asperities (referred to as wetted), corresponding to lower experimental contact angles. A transition between the Cassie and Wenzel regimes corresponds to a set of well-defined parameters. By smoothly depositing water drops on the surfaces, this transition is observed for surface parameter values far from the calculated ones for the thermodynamic transition, therefore offering evidence for the existence of metastable composite states. For all studied parameters, the position of the experimental transition correlates well with a rough estimation of the energy barrier to be overcome from a composite metastable state in order to reach the thermodynamically favored Wenzel state. This energy barrier is estimated as the surface energy variation between the Cassie state and the hypothetical composite state with complete filling of the surface asperities by water, keeping the contact angle constant.

17.
Psychiatr Serv ; 57(2): 172-4, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16452691

ABSTRACT

Studies have shown that teaching persons with mental illness to identify and cope with their real-life problems yields substantial clinical improvements. In Italy a structured problem-solving group was established in a day treatment center in 2003. This column describes the approach and focuses on the outcomes achieved by 15 patients with severe mental illness who were in this group. After completion of the problem-solving program, significant improvements were noted in symptom scores on the Positive and Negative Syndrome Scale and in problem-solving and neurocognitive test performance, with further improvements six months after completion of the group sessions. Problem-solving training may contribute to improved neurocognition and symptoms.


Subject(s)
Cognitive Behavioral Therapy/methods , Problem Solving , Psychotic Disorders/rehabilitation , Chronic Disease , Humans , Italy , Mental Health Services
18.
Med Secoli ; 17(2): 343-61, 2005.
Article in Italian | MEDLINE | ID: mdl-17152190

ABSTRACT

With about 65000 volumes, the Roudnice Lobkowicz Library, recently restituted to the owner and reconstructed at Nelahozeves Castle, is one of the greatest aristocratic libraries of Middle Europe. The library holds an extremely rich collection of medical books, starting from manuscripts and incunabula. Following up the development of studies started in the last years in the Library focused on provenances, collecting and with the reception of books throughout the centuries, the research is a survey of the medical literature present in the library. It is an attempt to individuate the kind of edition as well as to determinate the origin of the items, to explain their presence according to the different provenances and possibly their use through the different periods. As result, is possible to determinate models of reception of medical books in aristocratic libraries.


Subject(s)
Books/history , Libraries, Medical/history , Czech Republic , History, 15th Century , History, 16th Century
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