911 resultados para ALLOGRAFT RECIPIENTS
Resumo:
Background The stimulation of acupoints along the meridians, but not the non-acupoints outside of the meridians, produces analgesia. Although the acupoint is defined at the body surface, the exact location of the acupoints is not known. This study aims to examine whether the intensity and duration of the analgesic effect of electroacupuncture (EA) at the Zusanli (ST36) and Sanynjiao acupoints (SP6) change according to the depth of the stimulation. Methods Ninety-six male Wistar rats classified as responders were arbitrarily allocated into 16 groups of six rats each. Six groups received EA with uninsulated acupuncture needles (type I) or needles that were immersed in varnish and had the varnish circularly peeled 0.2 mm from the tip (type II), 0.2 mm at 3 mm (type III) or 5 mm (type IV) from the tip, or 0.2 mm at 5 and 1 mm from the tip (type V), or EA sham for 20 min. Five groups received injection of formalin into the acupoint bilaterally at 5 mm or 1 mm deep into ST36, 5 mm below ST36 but inserting the needle at 45° to the skin surface, or 5 mm deep into non-acupoints. The remaining groups received intraplantar injection of saline, 1% or 2.5% formalin. The analgesic effects were measured by the rat tail-flick test. Results The bilateral stimulation of ST36 and SP6 by uninsulated or insulated needles produced analgesia in the rat tail-flick test. The stronger and longer lasting effects occurred after EA with the types I and V needles, or injection of formalin 5 mm deep into ST36. The remaining needles produced weaker and shorter lasting effects. Slow analgesic effect also occurred after formalin injection at 1 mm or 5 mm below ST36 by inserting the needle at 45° to the skin surface. Conclusion The experimental results suggest that the efficacy of the EA stimulation depends on the spatial distribution of the current density under the needling surface rather than only the acupoint or the depth of needling.
Resumo:
Abstract Background Saliva is a key element of interaction between hematophagous mosquitoes and their vertebrate hosts. In addition to allowing a successful blood meal by neutralizing or delaying hemostatic responses, the salivary cocktail is also able to modulate the effector mechanisms of host immune responses facilitating, in turn, the transmission of several types of microorganisms. Understanding how the mosquito uses its salivary components to circumvent host immunity might help to clarify the mechanisms of transmission of such pathogens and disease establishment. Methods Flow cytometry was used to evaluate if increasing concentrations of A. aegypti salivary gland extract (SGE) affects bone marrow-derived DC differentiation and maturation. Lymphocyte proliferation in the presence of SGE was estimated by a colorimetric assay. Western blot and Annexin V staining assays were used to assess apoptosis in these cells. Naïve and memory cells from mosquito-bite exposed mice or OVA-immunized mice and their respective controls were analyzed by flow cytometry. Results Concentration-response curves were employed to evaluate A. aegypti SGE effects on DC and lymphocyte biology. DCs differentiation from bone marrow precursors, their maturation and function were not directly affected by A. aegypti SGE (concentrations ranging from 2.5 to 40 μg/mL). On the other hand, lymphocytes were very sensitive to the salivary components and died in the presence of A. aegypti SGE, even at concentrations as low as 0.1 μg/mL. In addition, A. aegypti SGE was shown to induce apoptosis in all lymphocyte populations evaluated (CD4+ and CD8+ T cells, and B cells) through a mechanism involving caspase-3 and caspase-8, but not Bim. By using different approaches to generate memory cells, we were able to verify that these cells are resistant to SGE effects. Conclusion Our results show that lymphocytes, and not DCs, are the primary target of A. aegypti salivary components. In the presence of A. aegypti SGE, naïve lymphocyte populations die by apoptosis in a caspase-3- and caspase-8-dependent pathway, while memory cells are selectively more resistant to its effects. The present work contributes to elucidate the activities of A. aegypti salivary molecules on the antigen presenting cell-lymphocyte axis and in the biology of these cells.
Resumo:
Background: The repair of large bone defects is a major orthopedic challenge because autologous bone grafts are not available in large amounts and because harvesting is often associated with donor-site morbidity. Considering that bone marrow stromal cells (BMSC) are responsible for the maintenance of bone turnover throughout life, we investigated bone repair at a site of a critically sized segmental defect in sheep tibia treated with BMSCs loaded onto allografts. The defect was created in the mid-portion of the tibial diaphysis of eight adult sheep, and the sheep were treated with ex-vivo expanded autologous BMSCs isolated from marrow aspirates and loaded onto cortical allografts (n = 4). The treated sheep were compared with control sheep that had been treated with cell-free allografts (n = 4) obtained from donors of the same breed as the receptor sheep. Results: The healing response was monitored by radiographs monthly and by computed tomography and histology at six, ten, fourteen, and eighteen weeks after surgery. For the cell-loaded allografts, union was established more rapidly at the interface between the host bone and the allograft, and the healing process was more conspicuous. Remodeling of the allograft was complete at 18 weeks in the cell-treated animals. Histologically, the marrow cavity was reestablished, with intertrabecular spaces being filled with adipose marrow and with evidence of focal hematopoiesis. Conclusions: Allografts cellularized with AOCs (allografts of osteoprogenitor cells) can generate great clinical outcomes to noncellularized allografts to consolidate, reshape, structurally and morphologically reconstruct bone and bone marrow in a relatively short period of time. These features make this strategy very attractive for clinical use in orthopedic bioengineering
Resumo:
Background Immunosuppressed individuals present serious morbidity and mortality from influenza, therefore it is important to understand the safety and immunogenicity of influenza vaccination among them. Methods This multicenter cohort study evaluated the immunogenicity and reactogenicity of an inactivated, monovalent, non-adjuvanted pandemic (H1N1) 2009 vaccine among the elderly, HIV-infected, rheumatoid arthritis (RA), cancer, kidney transplant, and juvenile idiopathic arthritis (JIA) patients. Participants were included during routine clinical visits, and vaccinated according to conventional influenza vaccination schedules. Antibody response was measured by the hemagglutination-inhibition assay, before and 21 days after vaccination. Results 319 patients with cancer, 260 with RA, 256 HIV-infected, 149 elderly individuals, 85 kidney transplant recipients, and 83 with JIA were included. The proportions of seroprotection, seroconversion, and the geometric mean titer ratios postvaccination were, respectively: 37.6%, 31.8%, and 3.2 among kidney transplant recipients, 61.5%, 53.1%, and 7.5 among RA patients, 63.1%, 55.7%, and 5.7 among the elderly, 59.0%, 54.7%, and 5.9 among HIV-infected patients, 52.4%, 49.2%, and 5.3 among cancer patients, 85.5%, 78.3%, and 16.5 among JIA patients. The vaccine was well tolerated, with no reported severe adverse events. Conclusions The vaccine was safe among all groups, with an acceptable immunogenicity among the elderly and JIA patients, however new vaccination strategies should be explored to improve the immune response of immunocompromised adult patients. (ClinicalTrials.gov, NCT01218685)
Resumo:
The general aim of this dissertation is to describe and analyse how public old-age care in Sweden has developed and changed during the last century. The study applies a provider perspective on how care has been planned and professionally carried out. A broader social policy perspective, studying old-age care at central/national as well as local/municipal level, is also developed. A special focus is directed at the large local variation in care and services for the elderly. The empirical base is comprised of official documents and other public sources, survey data from interviews with elderly recipients of public old-age care, and official statistics on publicly financed and controlled old-age care and services. Study I addresses the development of old-age care in Sweden during the twentieth century by studying an important occupation in this field – the supervisors and their professional roles, tasks and working conditions. Throughout, the roles of supervisors have followed the prevailing official policy on the proper way to provide care for elderly people in Sweden; from poor relief at the beginning of the 1900s, via a generous level of services in the 1960s and 1970s, to today’s restricted and economy-controlled mode of operation. Study II describes and compares two main forms of public old-age care in Sweden today, home help services and institutional care. The care-load found in home-based care was comparable to and sometimes even larger than in service-homes and other institutions, indicating that large care needs among elderly people in Sweden today can be met in their homes as well as in institutional settings. Studies III and IV analyse the local variation in public old-age care in Sweden. During the last decades there has been an overall decline in home help services. The coverage of home help for elderly people shows large differences between municipalities throughout this period, and the relative variation has increased. The local disparity seems to depend more on historical factors, e.g., previous coverage rates, than on the present municipal situation in levels of need or local economy and politics. In an introductory part the four papers are linked together by an outline of the demographic situation and the social policy model for old-age care in Sweden. Trends that have been apparent over time, e.g. professionalisation and market orientation, are traced and discussed. Conflicts between prevailing ideologies are analysed, in regards to for instance home-based and institution-based care, social and medical culture, and local and central levels of decision-making. ’Welfare municipality’, ‘path dependency’, and ‘decentralisation’ are suggested as a conceptual framework for describing the large and increasing local variations in old-age care. Finally, implications of the four studies with regard to old-age care policy and further research are discussed.
Resumo:
This dissertation takes a step towards providing a better understanding of post-socialist welfare state development from a theoretical as well as an empirical perspective. The overall analytical goal of this thesis has been to critically assess the development of social policies in Estonia, Latvia and Lithuania using them as illustrative examples of post-socialist welfare state development in the light of the theories, approaches and typologies that have been developed to study affluent capitalist democracies. The four studies included in this dissertation aspire to a common aim in a number of specific ways. The first study tries to place the ideal-typical welfare state models of the Baltic States within the well-known welfare state typologies. At the same time, it provides a rich overview of the main social security institutions in the three countries by comparing them with each other and with the previous structures of the Soviet period. It examines the social insurance institutions of the Baltic States (old-age pensions, unemployment insurance, short-term benefits, sickness, maternity and parental insurance and family benefits) with respect to conditions of eligibility, replacement rates, financing and contributions. The findings of this study indicate that the Latvian social security system can generally be labelled as a mix of the basic security and corporatist models. The Estonian social security system can generally also be characterised as a mix of the basic security and corporatist models, even if there are some weak elements of the targeted model in it. It appears that the institutional changes developing in the social security system of Lithuania have led to a combination of the basic security and targeted models of the welfare state. Nevertheless, as the example of the three Baltic States shows, there is diversity in how these countries solve problems within the field of social policy. In studying the social security schemes in detail, some common features were found that could be attributed to all three countries. Therefore, the critical analysis of the main social security institutions of the Baltic States in this study gave strong supporting evidence in favour of identifying the post-socialist regime type that is already gaining acceptance within comparative welfare state research. Study Two compares the system of social maintenance and insurance in the Soviet Union, which was in force in the three Baltic countries before their independence, with the currently existing social security systems. The aim of the essay is to highlight the forces that have influenced the transformation of the social policy from its former highly universal, albeit authoritarian, form, to the less universal, social insurance-based systems of present-day Estonia, Latvia and Lithuania. This study demonstrates that the welfare–economy nexus is not the only important factor in the development of social programs. The results of this analysis revealed that people's attitudes towards distributive justice and the developmental level of civil society also play an important part in shaping social policies. The shift to individualism in people’s mentality and the decline of the labour movement, or, to be more precise, the decline in trade union membership and influence, does nothing to promote the development of social rights in the Baltic countries and hinders the expansion of social policies. The legacy of the past has been another important factor in shaping social programs. It can be concluded that social policy should be studied as if embedded not only in the welfare-economy nexus, but also in the societal, historical and cultural nexus of a given society. Study Three discusses the views of the state elites on family policy within a wider theoretical setting covering family policy and social policy in a broader sense and attempts to expand this analytical framework to include other post-socialist countries. The aim of this essay is to explore the various views of the state elites in the Baltics concerning family policy and, in particular, family benefits as one of the possible explanations for the observed policy differences. The qualitative analyses indicate that the Baltic States differ significantly with regard to the motives behind their family policies. Lithuanian decision-makers seek to reduce poverty among families with children and enhance the parents’ responsibility for bringing up their children. Latvian policy-makers act so as to increase the birth rate and create equal opportunities for children from all families. Estonian policy-makers seek to create equal opportunities for all children and the desire to enhance gender equality is more visible in the case of Estonia in comparison with the other two countries. It is strongly arguable that there is a link between the underlying motives and the kinds of family benefits in a given country. This study, thus, indicates how intimately the attitudes of the state bureaucrats, policy-makers, political elite and researchers shape social policy. It confirms that family policy is a product of the prevailing ideology within a country, while the potential influence of globalisation and Europeanisation is detectable too. The final essay takes into account the opinions of welfare users and examines the performances of the institutionalised family benefits by relying on the recipients’ opinions regarding these benefits. The opinions of the populations as a whole regarding government efforts to help families are compared with those of the welfare users. Various family benefits are evaluated according to the recipients' satisfaction with those benefits as well as the contemporaneous levels of subjective satisfaction with the welfare programs related to the absolute level of expenditure on each program. The findings of this paper indicate that, in Latvia, people experience a lower level of success regarding state-run family insurance institutions, as compared to those in Lithuania and Estonia. This is deemed to be because the cash benefits for families and children in Latvia are, on average, seen as marginally influencing the overall financial situation of the families concerned. In Lithuania and Estonia, the overwhelming majority think that the family benefit systems improve the financial situation of families. It appears that recipients evaluated universal family benefits as less positive than targeted benefits. Some universal benefits negatively influenced the level of general satisfaction with the family benefits system provided in the countries being researched. This study puts forward a discussion about whether universalism is always more legitimate than targeting. In transitional economies, in which resources are highly constrained, some forms of universal benefits could turn out to be very expensive in relative terms, without being seen as useful or legitimate forms of help to families. In sum, by closely examining the different aspects of social policy, this dissertation goes beyond the over-generalisation of Eastern European welfare state development and, instead, takes a more detailed look at what is really going on in these countries through the examples of Lithuania, Latvia and Estonia. In addition, another important contribution made by this study is that it revives ‘western’ theoretical knowledge through ‘eastern’ empirical evidence and provides the opportunity to expand the theoretical framework for post-socialist societies.
Resumo:
Industrial and domestic sewage effluents have been found to cause reproductive disorders in wild fish, often as a result of the interference of compounds in the effluents with the endocrine system. This thesis describes laboratory-based exposure experiments and a field survey that were conducted with juveniles of the three-spined stickleback, Gasterosteus aculeatus. This small teleost is a common fish in Swedish coastal waters and was chosen as an alternative to non-native test species commonly used in endocrine disruption studies, which allows the comparison of field data with results from laboratory experiments. The aim of this thesis was to elucidate 1) if genetic sex determination and differentiation can be disturbed by natural and synthetic steroid hormones and 2) whether this provides an endpoint for the detection of endocrine disruption, 3) to evaluate the applicability of specific estrogen- and androgen-inducible marker proteins in juvenile three-spined sticklebacks, 4) to investigate whether estrogenic and/or androgenic endocrine disrupting activity can be detected in effluents from Swedish pulp mills and domestic sewage treatment plants and 5) whether such activity can be detected in coastal waters receiving these effluents. Laboratory exposure experiments found juvenile three-spined sticklebacks to be sensitive to water-borne estrogenic and androgenic steroid substances. Intersex – the co-occurrence of ovarian and testicular tissue in gonads – was induced by 17β-estradiol (E2), 17α-ethinylestradiol (EE2), 17α-methyltestosterone (MT) and 5α-dihydrotestosterone (DHT). The first two weeks after hatching was the phase of highest sensitivity. MT was ambivalent by simultaneously eliciting masculinizing and feminizing effects. When applying a DNA-based method for genetic sex identification, it was found that application of MT only during the first two weeks after hatching caused total and apparently irreversible development of testis in genetic females. E2 caused gonad type reversal from male to female. E2 and EE2 induced vitellogenin - the estrogen-responsive yolk precursor protein, while DHT and MT induced spiggin – the androgen-responsive glue protein of the stickleback. None of the effluents from two pulp mills and two domestic sewage treatment plants had any estrogenic or androgenic activity. Juvenile three-spined sticklebacks were collected during four subsequent summers at the Swedish Baltic Sea coast in recipients of effluents from pulp mills and a domestic sewage treatment plant as well as remote reference sites. No sings of endocrine disruption were observed at any site, when studying gonad development or marker proteins, except for a deviation of sex ratios at a reference site. The three-spined stickleback – with focus on the juvenile stage – was found to be a sensitive species suitable for the study of estrogenic and androgenic endocrine disruption.
Resumo:
Introduction. Cardiovascular disease (CVD) represents the main cause of morbidity and mortality in kidney recipients. This study was undertaken to assess the impact of functional polymorphisms located in cytokine and apoptosis genes on CVD after kidney transplantation. Cytokine polymorphisms, generally located in gene regulatory regions, are associated with high and low cytokine production and are likely to modulate the magnitude of inflammatory responses following transplantation, depending on the balance between the levels of pro-inflammatory and antiinflammatory cytokines. The role of apoptosis in atherosclerosis has not been completely elucidated, and here we explored the hypothesis that the heterogeneity in cardiovascular risk in kidney recipients may also be linked to functional polymorphisms involved in apoptosis induction. Purpose. In the search for relevant genetic markers of predisposition to CVD after renal transplant, the present investigation was undertaken to identify the clinical impact of polymorphisms of cytokines TNF-α, TGF-β, IL-10, IL-6, IFN-γ and IL-8 and of apoptosis genes Fas and Caspase 9 in a population of kidney transplant recipients. Materials and methods. The study involved 167 patients who received cadaveric kidney transplantation at our centre between 1997 and 2005 (minimum follow-up of 12 months); 35 of them had experienced cardiovascular events (CVD group) and 132 had no cardiovascular complications (non-CVD group). Genotyping was performed using RFLP (Restriction Fragment Length Polymorphism) for RFLP per IL-8/T-251A, Fas/G-670A e Casp9/R221Q polymorphism and SSP (Sequence Specific Primer) for TNF-α/G-308A, TGF-β/L10P, TGF-β/R25P, IL-10/G-1082A, IL- 10/C-819T, IL-10/C-592A, IL-6/G-174C, IFN-γ/T+874A polymorphisms.Results. We found a significant difference in TNF-α and IL-10 genotype frequencies between the patients who had suffered cardiovascular events and those with no CVD history. The high producer genotype for proflogistic cytokine TNF-α appeared to have a significantly superior prevalence in the CVD group compared to the non-CVD group (40.0% vs 21.2%) and it resulted in a 2.4-fold increased cardiovascular risk (OR=2.361; p=0.0289). On the other hand, the high producer genotype for the antiinflammatory cytokine IL-10 was found in 2.8% of the CVD group and in 16.7% of non-CVD group; logistic regression showed a 0.3-fold reduced risk of CVD associated with genetically determined high IL-10 production (OR=0.278; p<0.0001). The other polymorphisms did not prove to have any impact on CVD. Conclusions. TNF-α and IL-10 gene polymorphisms might represent cardiovascular risk markers in renal transplant recipients.
Resumo:
Hepatitis B virus (HBV) recurrence after orthotopic liver transplantation (OLT) is associated with poor graft and patient survival. Treatment with HBV-specific immunoglobulins (HBIG) in combination with nucleos(t)ide analogs is effective in preventing HBV reinfection of the graft and improving OLT outcome. However, the combined immunoprophylaxis has several limitations, mainly the high cost and the lack of standard schedules about duration. So far, the identification of markers able to predict the reinfection risk is needed. Although the HBV-specific immune response is believed to play an essential role in disease outcome, HBV-specific cellular immunity in viral containment in OLT recipients is unclear. To test whether or not OLT recipients maintain robust HBV-specific cellular immunity, the cellular immune response against viral nucleocapsid and envelope-protein of HBV was assessed in 15 OLT recipients and 27 individuals with chronic and 24 subjects with self-limited HBV infection, respectively. The data demonstrate that OLT recipients mounted fewer but stronger clusters of differentiation (CD)8 T cell responses than subjects with self-limited HBV infection and showed a preferential targeting of the nucleocapsid antigen. This focused response pattern was similar to responses seen in chronically infected subjects with undetectable viremia, but significantly different from patients who presented with elevated HBV viremia and who mounted mainly immune responses against the envelope protein. In conclusion, virus-specific CD4 T cell–mediated responses were only detected in subjects with self-limited HBV infection. Thus, the profile of the cellular immunity against HBV was in immune suppressed patients similar to subjects with chronic HBV infection with suppressed HBV-DNA.
Resumo:
Lung transplantation is a widely accepted therapeutic option for end stage lung disease. Clinical outcome is yet challenged by primary graft failure responsible for the majority of the early mortality, by chronic allograft dysfunction and chronic rejection accounting for more than 30% of deaths after the third postoperative year. Pulmonary surfactant proteins (SP) A, B, C and D are one of the first host defense mechanisms the lung can mount. SP-A in particular, produced by the type II pneumocytes, is active in the innate and adaptive immune system being an opsonin, but also regulating the macrophage and lymphocyte response. The main hypothesis for this project is that pulmonary surfactant protein A polymorphism may determine the early and long term lung allograft survival. Of note SP-A biologic activity seems to be genetically determined and SP-A polymorphisms have been associated to various lung disease. The two SP-A genes SP-A1 and SP-A2 have several polymorphisms within the coding region, SP-A1 (6A, 6A2-20), and SP-A2(1A, 1A0-13). The SP-A gene expression is regulated by cAMP, TTF-1 and glucocorticoids. In vitro studies have indicated that SP-A1 and SP-A2 gene variants may have a variable response to glucocorticoids. We proposed to determine if SP-A gene polymorphism predicts primary graft dysfunction and/or chronic lung allograft dysfunction and if SP-A may serve as a biomarker of lung allograft dysfunction. We also proposed to study the interaction between immunosuppressive drugs and SP-A expression and determine whether this is dependent on SP-A polymorphisms. This study will generate novel information improving our understanding of lung allograft dysfunction. It is conceivable that the information will stimulate the interest for a multi centre study to investigate if SP-A polymorphism may be integrated in the donor lung selection criteria and/or to implement post transplant tailored immunosuppression.
Resumo:
Tumors involving bone and soft tissues are extremely challenging situations. With the recent advances of multi-modal treatment, not only the type of surgery has moved from amputation to limb-sparing procedures, but also the survivorship has improved considerably and reconstructive techniques have the goal to allow a considerably higher quality of life. In bone reconstruction, tissue engineering strategies are the main area of research. Re-vascularization and re-vitalisation of a massive allograft would considerably improve the outcome of biological reconstructions. Using a rabbit animal model, in this study we showed that, by implanting a vascular pedicle inside a weight bearing massive cortical allograft, the bone regeneration inside the allograft was higher compared to the non-vascularized implants, given the patency of the vascular pedicle. Improvement in the animal model and the addition of Stem Cells and Growth factors will allow a further improvement in the results. In soft tissue tumors, free and pedicled flaps have been proven to be of great help as reconstruction strategies. In this study we analyzed the functional and overall outcome of 14 patients who received a re-innervated vascularized flap. We have demonstrated that the use of the innovative technique of motor re-innervated muscular flaps is effective when the resection involves important functional compartments of the upper or lower limb, with no increase of post-operative complications. Although there was no direct comparison between this type of reconstruction and the standard non-innervated reconstruction, we underlined the remarkable high overall functional scores and patient satisfaction following this procedure.
Resumo:
Il CMV è l’agente patogeno più frequente dopo trapianto (Tx) di cuore determinando sia sindromi cliniche organo specifiche sia un danno immunomediato che può determinare rigetto acuto o malattia coronarica cronica (CAV). I farmaci antivirali in profilassi appaiono superiori all’approccio pre-sintomatico nel ridurre gli eventi da CMV, ma l’effetto anti-CMV dell’everolimus (EVE) in aggiunta alla profilassi antivirale non è stato ancora analizzato. SCOPO DELLO STUDIO: analizzare l’interazione tra le strategie di profilassi antivirale e l’uso di EVE o MMF nell’incidenza di eventi CMV correlati (infezione, necessità di trattamento, malattia/sindrome) nel Tx cardiaco. MATERIALI E METODI: sono stati inclusi pazienti sottoposti a Tx cardiaco e trattati con EVE o MMF e trattamento antivirale di profilassi o pre-sintomatico. L’infezione da CMV è stata monitorata con antigenemia pp65 e PCR DNA. La malattia/sindrome da CMV è stato considerato l’endpoint principale. RISULTATI: 193 pazienti (di cui 10% D+/R-) sono stati inclusi nello studio (42 in EVE e 149 in MMF). Nel complesso, l’infezione da CMV (45% vs. 79%), la necessità di trattamento antivirale (20% vs. 53%), e la malattia/sindrome da CMV (2% vs. 15%) sono risultati significativamente più bassi nel gruppo EVE che nel gruppo MMF (tutte le P<0.01). La profilassi è più efficace nel prevenire tutti gli outcomes rispetto alla strategia pre-sintomatica nei pazienti in MMF (P 0.03), ma non nei pazienti in EVE. In particolare, i pazienti in EVE e strategia pre-sintomatica hanno meno infezioni da CMV (48 vs 70%; P=0.05), e meno malattia/sindrome da CMV (0 vs. 8%; P=0.05) rispetto ai pazienti in MMF e profilassi. CONCLUSIONI: EVE riduce significamene gli eventi correlati al CMV rispetto al MMF. Il beneficio della profilassi risulta conservato solo nei pazienti trattati con MMF mentre l’EVE sembra fornire un ulteriore protezione nel ridurre gli eventi da CMV senza necessità di un estensivo trattamento antivirale.
Resumo:
Critical lower limb ischemia is a severe disease. A common approach is infrainguinal bypass. Synthetic vascular prosthesis, are good conduits in high-flow low-resistance conditions but have difficulty in their performance as small diameter vessel grafts. A new approach is the use of native decellularized vascular tissues. Cell-free vessels are expected to have improved biocompatibility when compared to synthetic and are optimal natural 3D matrix templates for driving stem cell growth and tissue assembly in vivo. Decellularization of tissues represent a promising field for regenerative medicine, with the aim to develop a methodology to obtain small-diameter allografts to be used as a natural scaffold suited for in vivo cell growth and pseudo-tissue assembly, eliminating failure caused from immune response activation. Material and methods. Umbilical cord-derived mesenchymal cells isolated from human umbilical cord tissue were expanded in advanced DMEM. Immunofluorescence and molecular characterization revealed a stem cell profile. A non-enzymatic protocol, that associate hypotonic shock and low-concentration ionic detergent, was used to decellularize vessel segments. Cells were seeded cell-free scaffolds using a compound of fibrin and thrombin and incubated in DMEM, after 4 days of static culture they were placed for 2 weeks in a flow-bioreactor, mimicking the cardiovascular pulsatile flow. After dynamic culture, samples were processed for histological, biochemical and ultrastructural analysis. Discussion. Histology showed that the dynamic culture cells initiate to penetrate the extracellular matrix scaffold and to produce components of the ECM, as collagen fibres. Sirius Red staining showed layers of immature collagen type III and ultrastructural analysis revealed 30 nm thick collagen fibres, presumably corresponding to the immature collagen. These data confirm the ability of cord-derived cells to adhere and penetrate a natural decellularized tissue and to start to assembly into new tissue. This achievement makes natural 3D matrix templates prospectively valuable candidates for clinical bypass procedures
Resumo:
INTRODUCTION. Late chronic allograft disfunction (CAD) is one of the more concerning issues in the management of patients (pts) with renal transplant (tx). Humoral immune response seems to play an important role in CAD pathogenesis. AIM OF THE STUDY. To identify the causes of late chronic allograft disfunction. METHODS. This study (march 2004-august 2011) enrolled pts who underwent renal biopsy (BR) because of CAD (increase of creatininemia (s-Cr) >30% and/or proteinuria >1g/day at least one year after tx). BR were classified according to 1997/2005 Banff classification. Histological evaluation of C4d (positive if >25%), glomerulitis, tubulitis, intimal arteritis, atrophy/fibrosis and arteriolar-hyalinosis were performed. Ab anti-HLA research at BR was an inclusion criteria. Pts were divided into two groups: with or without transplant glomerulopathy (CTG). RESULTS. Evaluated BR: 93/109. BR indication: impaired s-Cr (52/93), proteinuria (23/93), both (18/93). Time Tx-BR: 7.4±6.3 yrs; s-Cr at BR: 2.7±1.4 mg/dl. CTG group(n=49) not-CTG group(n=44) p Time tx-BR (yrs) 9.3±6.7 5.3±5.2 0.002 Follow-up post-BR (yrs) 2.7±1.8 4.1±1.4 0.0001 s-Cr at BR (mg/dl) 2.9±1.3 2.4±1.5 NS Rate (%) of pts: Proteinuria at BR 61% 25% 0.0004 C4d+ 84% 25% <0.0001 Ab anti-HLA+ 71% 30% 0.0001 C4d+ and/or Ab antiHLA 92% 43% 0.0001 Glomerulitis 76% 16% <0.0001 Tubulitis 6% 32% 0.0014 Intimal arteritis 18% 0% 0.002 Arteriolar hyalinosis 65% 50% NS Atrophy/fibrosis 80% 77% NS Graft survival 45% 86% 0.00005 Histological Diagnosis: CTG group (n=49:Chronic rejection 94%;IgA recurrence + humoral activity 4%;IIA acute rejection + humoral activity 2%. Not-CTG group (n=44: GN recurrence 27%;IF/TA 23%; acute rejection 23%;BKV nephritis 9%; mild not specific alterations 18%. CONCLUSIONS: CTG is the morphological lesion mainly related to CAD. In the 92% of the cases it is associated with markers of immunological activity. It causes graft failure within five years after diagnosis in 55% of pts.
Resumo:
Donor-derived CD8+ cytotoxic T lymphocytes (CTLs) eliminating host leukemic cells mediate curative graft-versus-leukemia (GVL) reactions after allogeneic hematopoietic stem cell transplantation (HSCT). The leukemia-reactive CTLs recognize hematopoiesis-restricted or broadly expressed minor histocompatibility and leukemia-associated peptide antigens that are presented by human leukocyte antigen (HLA) class I molecules on recipient cells. The development of allogeneic CTL therapy in acute myeloid leukemia (AML) is hampered by the poor efficiency of current techniques for generating leukemia-reactive CTLs from unprimed healthy donors in vitro. In this work, a novel allogeneic mini-mixed lymphocyte/leukemia culture (mini-MLLC) approach was established by stimulating CD8+ T cells isolated from peripheral blood of healthy donors at comparably low numbers (i.e. 10e4/well) with HLA class I-matched primary AML blasts in 96-well microtiter plates. Before culture, CD8+ T cells were immunomagnetically separated into CD62L(high)+ and CD62L(low)+/neg subsets enriched for naive/central memory and effector memory cells, respectively. The application of 96-well microtiter plates aimed at creating multiple different responder-stimulator cell compositions in order to provide for the growth of leukemia-reactive CTLs optimized culture conditions by chance. The culture medium was supplemented with interleukin (IL)-7, IL-12, and IL-15. On day 14, IL-12 was replaced by IL-2. In eight different related and unrelated donor/AML pairs with complete HLA class I match, numerous CTL populations were isolated that specifically lysed myeloid leukemias in association with various HLA-A, -B, or -C alleles. These CTLs recognized neither lymphoblastoid B cell lines of donor and patient origin nor primary B cell leukemias expressing the corresponding HLA restriction element. CTLs expressed T cell receptors of single V-beta chain families, indicating their clonality. The vast majority of CTL clones were obtained from mini-MLLCs initiated with CD8+ CD62L(high)+ cells. Using antigen-specific stimulation, multiple CTL populations were amplified to 10e8-10e10 cells within six to eight weeks. The capability of mini-MLLC derived AML-reactive CTL clones to inhibit the engraftment of human primary AML blasts was investigated in the immunodeficient nonobese diabetic/severe combined immune deficient IL-2 receptor common γ-chain deficient (NOD/SCID IL2Rγnull) mouse model. The leukemic engraftment in NOD/SCID IL2Rγnull was specifically prevented if inoculated AML blasts had been pre-incubated in vitro with AML-reactive CTLs, but not with anti-melanoma control CTLs. These results demonstrate that myeloid leukemia-specific CTL clones capable of preventing AML engraftment in mice can be rapidly isolated from CD8+ CD62L(high)+ T cells of healthy donors in vitro. The efficient generation and expansion of these CTLs by the newly established mini-MLLC approach opens the door for several potential applications. First, CTLs can be used within T cell-driven antigen identification strategies to extend the panel of molecularly defined AML antigens that are recognizable by T cells of healthy donors. Second, because these CTLs can be isolated from the stem cell donor by mini-MLLC prior to transplantation, they could be infused into AML patients as a part of the stem cell allograft, or early after transplantation when the leukemia burden is low. The capability of these T cells to expand and function in vivo might require the simultaneous administration of AML-reactive CD4+ T cells generated by a similar in vitro strategy or, less complex, the co-transfer of CD8-depleted donor lymphocytes. To prepare clinical testing, the mini-MLLC approach should now be translated into a protocol that is compatible with good manufacturing practice guidelines.