262 resultados para major gifts
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BACKGROUND: Limited data have been published on the normal size of the ascending aorta (AA) measured using transthoracic echocardiography (TTE). METHODS: AA diameters were measured in 1799 patients with normal cardiac findings on TTE and compared with the diameters of the sinus of Valsalva (SoV). RESULTS: Mean diameters in men and women, respectively, were 3.4 and 3.1 cm for the SoV and 3.2 and 3.0 cm for the AA. The sizes of the SoV and the AA showed strong correlations with age, age squared, and body surface area. The 5th and 95th percentile curves for the SoV and AA showed faster growth of diameters in early adulthood compared with old age. The dimensions of the SoV were larger than those of the AA (mean differences, 0.19 cm in men and 0.08 cm in women), and the difference between the SoV and AA was negatively correlated with age. CONCLUSION: The findings of this study stress the importance of indexing dimensions of the SoV and the AA to age and body surface area separately for men and women.
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The possible immunomodulatory role of polymorphonuclear leukocytes (PMN) in CD4+ T lymphocyte differentiation in mice was examined by studying the effect of transient depletion of PMN during the early phase after Leishmania major delivery. A single injection of the PMN-depleting NIMP-R14 mAb 6 h before infection with L. major prevented the early burst of IL-4 mRNA transcription otherwise occurring in the draining lymph node of susceptible BALB/c mice. Since this early burst of IL-4 mRNA transcripts had previously been shown to instruct Th2 differentiation in mice from this strain, we examined the effect of PMN depletion on Th subset differentiation at later time points after infection. The transient depletion of PMN in BALB/c mice was sufficient to inhibit Th2 cell development otherwise occurring after L. major infection. Decreased Th2 responses were paralleled with partial resolution of the footpad lesions induced by L. major. Furthermore, draining lymph node-derived CD4+ T cells from PMN-depleted mice remained responsive to IL-12 after L. major infection, unlike those of infected BALB/c mice receiving control Ab. PMN depletion had no effect when the NIMP-R14 mAb was injected 24 h postinfection. The protective effect of PMN depletion was shown to be IL-12 dependent, as concomitant neutralization of IL-12 reversed the protective effect of PMN depletion. These results suggest a role for an early wave of PMN in the development of the Th2 response characteristic of mice susceptible to infection with L. major.
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The bioavailability of nitric oxide (NO) within the vascular wall is limited by superoxide anions (O2.-). The relevance of extracellular superoxide dismutase (ecSOD) for the detoxification of vascular O2.- is unknown. We determined the involvement of ecSOD in the control of blood pressure and endothelium-dependent responses in angiotensin II-induced hypertension and renovascular hypertension induced by the two-kidney, one-clip model in wild-type mice and mice lacking the ecSOD gene. Blood pressure was identical in sham-operated ecSOD+/+ and ecSOD-/- mice. After 6 days of angiotensin II-treatment and 2 and 4 weeks after renal artery clipping, blood pressure was significantly higher in ecSOD-/- than ecSOD+/+ mice. Recombinant ecSOD selectively decreased blood pressure in hypertensive ecSOD-/- mice, whereas ecSOD had no effect in normotensive and hypertensive ecSOD+/+ mice. Compared with sham-operated ecSOD+/+ mice, sham-operated ecSOD-/- mice exhibited attenuated acetylcholine-induced relaxations. These responses were further depressed in vessels from clipped animals. Vascular O2.-, as measured by lucigenin chemiluminescence, was higher in ecSOD-/- compared with ecSOD+/+ mice and was increased by clipping. The antioxidant tiron normalized relaxations in vessels from sham-operated and clipped ecSOD-/-, as well as from clipped ecSOD+/+ mice. In contrast, in vivo application of ecSOD selectively enhanced endothelium-dependent relaxation in vessels from ecSOD-/- mice. These data reveal that endogenous ecSOD is a major antagonistic principle to vascular O2.-, controlling blood pressure and vascular function in angiotensin II-dependent models of hypertension. ecSOD is expressed in such an abundance that even in situations of high oxidative stress no relative lack of enzyme activity occurs.
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Artificial radionuclides ((137)Cs, (90)Sr, Pu, and (241)Am) are present in soils because of Nuclear Weapon Tests and accidents in nuclear facilities. Their distribution in soil depth varies according to soil characteristics, their own chemical properties, and their deposition history. For this project, we studied the atmospheric deposition of (137)Cs, (90)Sr, Pu, (241)Am, (210)Pb, and stable Pb. We compared the distribution of these elements in soil profiles from different soil types from an alpine Valley (Val Piora, Switzerland) with the distribution of selected major and trace elements in the same soils. Our goals were to explain the distribution of the radioisotopes as a function of soil parameters and to identify stable elements with analogous behaviors. We found that Pu and (241)Am are relatively immobile and accumulate in the topsoil. In all soils, (90)Sr is more mobile and shows some accumulations at depth into Fe-Al rich horizons. This behavior is also observed for Cu and Zn, indicating that these elements may be used as chemical analogues for the migration of (90)Sr into the soil.
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BACKGROUND: To determine the extent to which major histoincompatibilities are recognized after bone marrow transplantation, we characterized the specificity of the cytotoxic T lymphocytes isolated during graft-versus-host disease. We studied three patients transplanted with marrow from donors who were histoincompatible for different types of HLA antigens. METHODS: Patient 1 was mismatched for one "ABDR-antigen" (HLA-A2 versus A3). Two patients were mismatched for antigens that would usually not be taken into account by standard selection procedures: patient 2 was mismatched for an "HLA-A subtype" (A*0213 versus A*0201), whereas patient 3 was mismatched for HLA-C (HLA-C*0501 versus HLA-C*0701). All three HLA class I mismatches were detected by a pretransplant cytotoxic precursor test. RESULTS: Analysis of the specificity of the cytotoxic T lymphocyte clones isolated after transplantation showed that the incompatibilities detected by the pretransplant cytotoxic precursor assay were the targets recognized during graft-versus-host disease. CONCLUSIONS: Independent of whether the incompatibility consisted of a "full" mismatch, a "subtype" mismatch, or an HLA-C mismatch, all clones recognized the incompatible HLA molecule. In addition, some of these clones had undergone antigen selection and were clearly of higher specificity than the ones established before transplantation, indicating that they had been participating directly in the antihost immune response.
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Rapport de synthèse La prévalence de l'hypertension artérielle, d'une dyslipidémie, d'une obésité et d'un tabagisme est élevée chez les patients qui souffrent d' une maladie coronarienne familiale précoce (MC-FP). L? e but de cette étude fut d'investiguer la prévalence de ces facteurs de risque cardiovasculaires au sein des membres d'une famille dont un patient est affecté d'une MC-FP. Nous avons étudié 108 familles différentes dont au minimum 2 frères/soeurs ont survécu à une maladie coronarienne précoce. Cette dernière fut définie par la survenue d'un événement coronarien avant l'âge de 51 ans pour les hommes et 56 ans pour les femmes. Au total, nous avons identifié 222 patients atteints de MC-FP chez qui 158 frères/soeurs, 197 enfants et 94 époux/épouses ne souffraient pas de maladie coronarienne. Ces parents proches furent comparés à un collectif d'individus "contrôles" issus de la population générale. Les frères/soeurs non affectés avaient une prévalence plus élevée d'hypertension artérielle (49% versus 24%, p<0.001), d'hypercholestérolémie (47% versus 34%, p=0.002), d'obésité abdominale (35% versus 24%, p=0.006) et de tabagisme (39% versus 24%, p=0.001) par rapport aux individus issus de la population générale. Parmi les enfants, une prévalence plus élevée d'hypertension artérielle fut identifiée chez les femmes, et une prévalence plus élevée d'hypercholestérolémie et d'obésité abdominale dans les deux sexes par rapport aux contrôles de la population générale. Aucune différence parmi les facteurs de risque cardiovasculaire n'a été observée entre les époux/ épouses et les contrôles. Les frères/soeurs affectés et non affectés par la MC-FP ont également été comparés entre eux. La prévalence des facteurs de risque était similaire dans les 2 groupes, sauf pour le tabagisme, qui avait une prévalence plus élevée chez les frères/sueurs affectés (76% versus 39%, p=0.008). La prévalence de l'hypertension artérielle, de l'obésité, et de la dyslipidémie est également élevée chez les parents de premier degré de patients atteints de MC-FP, mais pas chez leurs époux/épouses. Ces personnes-là requièrent donc une attention médicale particulière en raison d'une vulnérabilité familiale et/ou génétique augmentée aux anomalies métaboliques athérogènes. Dans ces familles, le tabagisme pourrait être le facteur déclenchant de la MC-FP.
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The motivation for this research initiated from the abrupt rise and fall of minicomputers which were initially used both for industrial automation and business applications due to their significantly lower cost than their predecessors, the mainframes. Later industrial automation developed its own vertically integrated hardware and software to address the application needs of uninterrupted operations, real-time control and resilience to harsh environmental conditions. This has led to the creation of an independent industry, namely industrial automation used in PLC, DCS, SCADA and robot control systems. This industry employs today over 200'000 people in a profitable slow clockspeed context in contrast to the two mainstream computing industries of information technology (IT) focused on business applications and telecommunications focused on communications networks and hand-held devices. Already in 1990s it was foreseen that IT and communication would merge into one Information and communication industry (ICT). The fundamental question of the thesis is: Could industrial automation leverage a common technology platform with the newly formed ICT industry? Computer systems dominated by complex instruction set computers (CISC) were challenged during 1990s with higher performance reduced instruction set computers (RISC). RISC started to evolve parallel to the constant advancement of Moore's law. These developments created the high performance and low energy consumption System-on-Chip architecture (SoC). Unlike to the CISC processors RISC processor architecture is a separate industry from the RISC chip manufacturing industry. It also has several hardware independent software platforms consisting of integrated operating system, development environment, user interface and application market which enables customers to have more choices due to hardware independent real time capable software applications. An architecture disruption merged and the smartphone and tablet market were formed with new rules and new key players in the ICT industry. Today there are more RISC computer systems running Linux (or other Unix variants) than any other computer system. The astonishing rise of SoC based technologies and related software platforms in smartphones created in unit terms the largest installed base ever seen in the history of computers and is now being further extended by tablets. An underlying additional element of this transition is the increasing role of open source technologies both in software and hardware. This has driven the microprocessor based personal computer industry with few dominating closed operating system platforms into a steep decline. A significant factor in this process has been the separation of processor architecture and processor chip production and operating systems and application development platforms merger into integrated software platforms with proprietary application markets. Furthermore the pay-by-click marketing has changed the way applications development is compensated: Three essays on major trends in a slow clockspeed industry: The case of industrial automation 2014 freeware, ad based or licensed - all at a lower price and used by a wider customer base than ever before. Moreover, the concept of software maintenance contract is very remote in the app world. However, as a slow clockspeed industry, industrial automation has remained intact during the disruptions based on SoC and related software platforms in the ICT industries. Industrial automation incumbents continue to supply systems based on vertically integrated systems consisting of proprietary software and proprietary mainly microprocessor based hardware. They enjoy admirable profitability levels on a very narrow customer base due to strong technology-enabled customer lock-in and customers' high risk leverage as their production is dependent on fault-free operation of the industrial automation systems. When will this balance of power be disrupted? The thesis suggests how industrial automation could join the mainstream ICT industry and create an information, communication and automation (ICAT) industry. Lately the Internet of Things (loT) and weightless networks, a new standard leveraging frequency channels earlier occupied by TV broadcasting, have gradually started to change the rigid world of Machine to Machine (M2M) interaction. It is foreseeable that enough momentum will be created that the industrial automation market will in due course face an architecture disruption empowered by these new trends. This thesis examines the current state of industrial automation subject to the competition between the incumbents firstly through a research on cost competitiveness efforts in captive outsourcing of engineering, research and development and secondly researching process re- engineering in the case of complex system global software support. Thirdly we investigate the industry actors', namely customers, incumbents and newcomers, views on the future direction of industrial automation and conclude with our assessments of the possible routes industrial automation could advance taking into account the looming rise of the Internet of Things (loT) and weightless networks. Industrial automation is an industry dominated by a handful of global players each of them focusing on maintaining their own proprietary solutions. The rise of de facto standards like IBM PC, Unix and Linux and SoC leveraged by IBM, Compaq, Dell, HP, ARM, Apple, Google, Samsung and others have created new markets of personal computers, smartphone and tablets and will eventually also impact industrial automation through game changing commoditization and related control point and business model changes. This trend will inevitably continue, but the transition to a commoditized industrial automation will not happen in the near future.
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There has been increasing attention to the subgroups of mood disorders and their boundaries with other mental disorders, particularly psychoses. The goals of the present paper were (1) to assess the familial aggregation and co-aggregation patterns of the full spectrum of mood disorders (that is, bipolar, schizoaffective (SAF), major depression) based on contemporary diagnostic criteria; and (2) to evaluate the familial specificity of the major subgroups of mood disorders, including psychotic, manic and major depressive episodes (MDEs). The sample included 293 patients with a lifetime diagnosis of SAF disorder, bipolar disorder and major depressive disorder (MDD), 110 orthopedic controls, and 1734 adult first-degree relatives. The diagnostic assignment was based on all available information, including direct diagnostic interviews, family history reports and medical records. Our findings revealed specificity of the familial aggregation of psychosis (odds ratio (OR)=2.9, confidence interval (CI): 1.1-7.7), mania (OR=6.4, CI: 2.2-18.7) and MDEs (OR=2.0, CI: 1.5-2.7) but not hypomania (OR=1.3, CI: 0.5-3.6). There was no evidence for cross-transmission of mania and MDEs (OR=.7, CI:.5-1.1), psychosis and mania (OR=1.0, CI:.4-2.7) or psychosis and MDEs (OR=1.0, CI:.7-1.4). The strong familial specificity of psychotic, manic and MDEs in this largest controlled contemporary family study challenges the growing assertion that the major types of mood disorders are manifestations of a common underlying diathesis.
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Bovine secretory IgA (SIgA), recently identified in colostrum, was shown to be homologous to human SIgA by immunologic cross-reaction. A quantitative study indicated that bovine SIgA, a minor component of colostrum, is a major immunoglobulin in most other external secretions including saliva, spermatic fluid, lacrimal, nasal and gastrointestinal secretions. SIgA was isolated from saliva. The free form of secretory component was found to be abundant in milk. A normal lactating cow produces about 1.2 g of this protein per day. Two forms of IgA were identified in serum: a normal serum IgA with no secretory antigenic determinant, and a small amount of SIgA. In vitro synthesis of SIgA by the salivary gland was studied by tissue cultures with incorporation of labeled amino acids.
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Les neutrophiles constituent la première ligne de défense contre un grand nombre de pathogènes. Après infection avec Leishmania major, les neutrophiles migrent rapidement et massivement au site d'infection par le parasite. Les neutrophiles sont d'importants acteurs dans l'orchestration de la réponse anti-Leishmania, via la sécrétion de nombreuses cytokines, chimiokines et composés stockés dans leurs granules. De plus, les neutrophiles interagissent avec les cellules présentatrices d'antigènes, telles que les cellules dendritiques et en conséquences contribuent au développement de la réponse adaptative. A ce jour, l'impact des neutrophiles sur 1'activation des cellules dendritiques et les possibles conséquences de l'interaction neutrophiles avec ces dernières sur l'évolution de la maladie suite à l'infection avec L. major reste peu connu. Ainsi, nous avons dans un premier temps investigué l'influence des neutrophiles sur 1'activation des cellules dendritiques in vitro. Suite à cela, nous avons analysé le rôle des neutrophiles sur 1'activation des cellules dendritiques présentes au site d'infection et dans les ganglions drainants in vivo, après inoculation intra-dermale de L. major dans le pavillon auriculaire de souris de souche C57BL/6 et BALB/c, ainsi que les conséquences de la déplétion des neutrophiles sur l'évolution de la maladie. Nous avons pu démontrer que les neutrophiles ont un impact négatif sur l'activation des cellules dendritiques exposées à L. major in vitro, via des mécanismes impliquant la sécrétion de Prostaglandines par les neutrophiles et la séquestration des parasites. La déplétion des neutrophiles dans les souris BALB/c durant les premiers jours après infection avec L. major dans le derme de l'oreille résulte en une augmentation de l'expression de marqueurs d'activation des cellules dendritiques présentes dans les ganglions drainants, mais pas au site d'infection. De plus, les souris BALB/c transitoirement déplétées en neutrophiles développent des lésions significativement plus petites, une réponse de type Th2 diminuée et une charge parasitaire plus faible au site d'infection que les souris non déplétées. La déplétion des neutrophiles dans les souris C57BL/6 n'a pas d'influence détectable sur l'activation des cellules dendritiques que ce soit au niveau des ganglions drainants ou au site d'infection. La progression de la lésion et la charge parasitaire ne sont pas affectées par la déplétion des neutrophiles, malgré le développement d'une réponse Th2 diminuée par rapport aux souris non déplétées. En résumé, dans les premières heures après infection, les neutrophiles ont un effet négatif sur l'activation des cellules dendritiques et sur la réponse anti-Leishmania dans les souris BALB/c tandis que leur rôle paraît moins important dans les souris C57BL/6. Ces résultats peuvent avoir d'importantes implications en terme de développement de nouveaux vaccins contre Leishmania. - Neutrophils constitute the first line of defense against a variety of pathogens. Following Leihmania major infection neutrophils migrate rapidly and massively to the site of parasite inoculation. They are important players in the orchestration of the anti-leishmania response through the release of a plethora of cytokines, chemokines and granular components. In addition, neutrophils interact with antigen-presenting cells such as dendritic cells (DCs) and thereby contribute to the development of the adaptive immune response. However, the impact of neutrophils on the activation of DCs and possible consequences on disease progression following L. major infection are poorly understood. Therefore, we first investigated the influence of neutrophils on DC activation in vitro. Next we analyzed the role of neutrophils on the activation of DCs present at the site of infection and in the draining lymph node (dLN) following inoculation of L. major in the ear pinna of C57BL/6 and BALB/c mice and analyzed the consequences of early neutrophil depletion on disease progression. We could demonstrate that neutrophils had a negative impact on the activation of DCs exposed to L. major in vitro through mechanisms involving neutrophil-derived prostaglandins and sequestration of parasites. In BALB/c mice, depletion of neutrophils during the first days of infection with L. major in the ear dermis increased the expression of activation markers on dLN DCs but not on DCs present at the site of infection. In addition, BALB/c mice transiently depleted of neutrophils developed significantly smaller lesions, a decreased Th2 immune response and harbored fewer parasites at the site of infection compared to non-depleted littermates. In C57BL/6, mice early depletion of neutrophils had no detectable impact on the activation of DCs both at the site of infection and in the dLN following L. major inoculation. Furthermore, depletion of neutrophils had no major effect on lesion evolution and parasite loads despite the development of a decreased Th2 immune response compared to non- depleted littermates. In summary, at the onset of infection, neutrophils are detrimental for DC activation and the anti-leishmania response in BALB/c mice while their role appears to be less important in C57BL/6 mice. These findings could have important implications for the design of new vaccination strategies.
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Enhanced brain apoptosis (neurons and glia) may be involved in major depression (MD) and schizophrenia (SZ), mainly through the activation of the intrinsic (mitochondrial) apoptotic pathway. In the extrinsic death pathway, pro-apoptotic Fas-associated death domain (FADD) adaptor and its non-apoptotic p-Ser194 FADD form have critical roles interacting with other death regulators such as phosphoprotein enriched in astrocytes of 15kDa (PEA-15) and extracellular signal-regulated kinase (ERK). The basal status of FADD (protein and messenger RNA (mRNA)) and the effects of psychotropic drugs (detected in blood/urine samples) were first assessed in postmortem prefrontal cortex of MD and SZ subjects (including a non-MD/SZ suicide group). In MD, p-FADD, but not total FADD (and mRNA), was increased (26%, n=24; all MD subjects) as well as p-FADD/FADD ratio (a pro-survival marker) in antidepressant-free MD subjects (50%, n=10). In contrast, cortical FADD (and mRNA), p-FADD, and p-FADD/FADD were not altered in SZ brains (n=21) regardless of antipsychotic medications (except enhanced mRNA in treated subjects). Similar negative results were quantified in the non-MD/SZ suicide group. In MD, the regulation of multifunctional PEA-15 (i.e., p-Ser116 PEA-15 blocks pro-apoptotic FADD and PEA-15 prevents pro-survival ERK action) and the modulation of p-ERK1/2 were also investigated. Cortical p-PEA-15 was not changed whereas PEA-15 was increased mainly in antidepressant-treated subjects (16-20%). Interestingly, cortical p-ERK1/2/ERK1/2 ratio was reduced (33%) in antidepressant-free when compared to antidepressant-treated MD subjects. The neurochemical adaptations of brain FADD (increased p-FADD and pro-survival p-FADD/FADD ratio), as well as its interaction with PEA-15, could play a major role to counteract the known activation of the mitochondrial apoptotic pathway in MD.
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Histone H1 in the parasitic protozoan Leishmania is a developmentally regulated protein encoded by the sw3 gene. Here we report that histone H1 variants exist in different Leishmania species and strains of L. major and that they are encoded by polymorphic genes. Amplification of the sw3 gene from the genome of three strains of L. major gave rise to different products in each strain, suggesting the presence of a multicopy gene family. In L. major, these genes were all restricted to a 50-kb Bg/II fragment found on a chromosomal band of 1.3 Mb (chromosome 27). The detection of RFLPs in this locus demonstrated its heterogeneity within several species and strains of Leishmania. Two different copies of sw3 (sw3.0 and sw3.1) were identified after screening a cosmid library containing L. major strain Friedlin genomic DNA. They were identical in their 5' UTRs and open reading frames, but differed in their 3' UTRs. With respect to the originally cloned copy of sw3 from L. major strain LV39, their open reading frames lacked a repeat unit of 9 amino acids. Immunoblots of L. guyanensis parasites transfected with these cosmids revealed that both copies could give rise to the histone H1 protein. The characterization of this locus will now make possible a detailed analysis of the function of histone H1 in Leishmania, as well as permit the dissection of the molecular mechanisms governing the developmental regulation of the sw3 gene.
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Extended pharmacological venous thromboembolism (VTE) prophylaxis beyond discharge is recommended for patients undergoing high-risk surgery. We prospectively investigated prophylaxis in 1,046 consecutive patients undergoing major orthopaedic (70%) or major cancer surgery (30%) in 14 Swiss hospitals. Appropriate in-hospital prophylaxis was used in 1,003 (96%) patients. At discharge, 638 (61%) patients received prescription for extended pharmacological prophylaxis: 564 (77%) after orthopaedic surgery, and 74 (23%) after cancer surgery (p < 0.001). Patients with knee replacement (94%), hip replacement (81%), major trauma (80%), and curative arthroscopy (73%) had the highest prescription rates for extended VTE prophylaxis; the lowest rates were found in patients undergoing major surgery for thoracic (7%), gastrointestinal (19%), and hepatobiliary (33%) cancer. The median duration of prescribed extended prophylaxis was longer in patients with orthopaedic surgery (32 days, interquartile range 14-40 days) than in patients with cancer surgery (23 days, interquartile range 11-30 days; p<0.001). Among the 278 patients with an extended prophylaxis order after hip replacement, knee replacement, or hip fracture surgery, 120 (43%) received a prescription for at least 35 days, and among the 74 patients with an extended prophylaxis order after major cancer surgery, 20 (27%) received a prescription for at least 28 days. In conclusion, approximately one quarter of the patients with major orthopaedic surgery and more than three quarters of the patients with major cancer surgery did not receive prescription for extended VTE prophylaxis. Future effort should focus on the improvement of extended VTE prophylaxis, particularly in patients undergoing major cancer surgery.
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Leishmania spp. are intracellular protozoan parasites that are delivered within the dermis of their vertebrate hosts. Within this peripheral tissue and the draining lymph node, they find and/or rapidly create dynamic microenvironments that determine their ultimate fate, namely their more or less successful expansion, and favour their transmission to another vertebrate host though a blood-feeding vector. Depending on their genetic characteristics as well as the genetic make-up of their hosts, once within the dermis Leishmania spp. very rapidly drive and maintain sustained T cell-dependent immune responses that arbitrate their ultimate fate within their hosts. The analysis of the parasitism exerted by Leishmania major in mice of different genetic backgrounds has allowed us to recognize some of the early and late mechanisms driven by this parasite that lead to either uncontrolled or restricted parasitism. Uncontrolled parasitism by Leishmania major characterizing mice from a few inbred strains (e.g. BALB/c) is associated with the expansion of parasite reactive Th2 CD4 lymphocytes and results from their rapid and sustained activity. In contrast, restricted parasitism characteristic of mice from the majority of inbred strains results from the development of a polarized parasite-specific Th1 CD4 response. This murine model of infection has already been and will continue to be particularly instrumental in dissecting the rules controlling the pathway of differentiation of T cells in vivo. In the long run, the understanding of these rules should contribute to the rational development of novel immunotherapeutic interventions against severe infectious diseases.