105 research outputs found
Factors influencing preoperative stress response in coronary artery bypass graft patients
BACKGROUND: In many studies investigating measures to attenuate the hemodynamic and humoral stress response during induction of anaesthesia, primary attention was paid to the period of endotracheal intubation since it has been shown that even short-lasting sympathetic cardiovascular stimulation may have detrimental effects on patients with coronary artery disease. The aim of this analysis was, however, to identify the influencing factors on high catecholamine levels before induction of anaesthesia. METHODS: Various potential risk factors that could impact the humoral stress response before induction of anaesthesia were recorded in 84 males undergoing coronary aortic bypass surgery, and were entered into a stepwise linear regression analysis. The plasma level of norepinephrine measured immediately after radial artery canulation was chosen as a surrogate marker for the humoral stress response, and it was used as the dependent variable in the regression model. Accordingly, the mean arterial blood pressure, heart rate and the calculated pressure-rate product were taken as parameters of the hemodynamic situation. RESULTS: Stepwise regression analysis revealed that the oral administration of low-dose clonidine (mean dose 1.75 μg·kg(-1)) on the morning of surgery was the only significant predictor (p = 0.004) of the high variation in preoperative norepinephrine plasma levels. This intervention decreased norepinephrine levels by more than 40% compared to no clonidine administration, from 1.26 to 0.75 nmol·l(-1). There was no evidence for dose-responsiveness of clonidine. All other potential predictors were removed from the model as insignificant (p > 0.05). The use of beta-blocker, ace-inhibitors, ejection fraction, and body mass index were significant determinants for the hemodynamic situation (heart rate, mean arterial pressure, pressure rate product) of the patient during the pre-induction period. CONCLUSION: The oral administration of clonidine is the only significant predictor for the observed variation of norepinephrine levels during the preoperative period. Lack of significant dose responsiveness suggests that even a low dose of the drug can attenuate the preoperative stress response and thus is recommended in cardiovascular high risk patients
Leishmania donovani: Immunostimulatory Cellular Responses of Membrane and Soluble Protein Fractions of Splenic Amastigotes in Cured Patient and Hamsters
Visceral leishmaniasis (VL), caused by the intracellular parasite Leishmania donovani, L. chagasi and L. infantum is characterized by defective cell-mediated immunity (CMI) and is usually fatal if not treated properly. An estimated 350 million people worldwide are at risk of acquiring infection with Leishmania parasites with approximately 500,000 cases of VL being reported each year. In the absence of an efficient and cost-effective antileishmanial drug, development of an appropriate long-lasting vaccine against VL is the need of the day. In VL, the development of a CMI, capable of mounting Th1-type of immune responses, play an important role as it correlate with recovery from and resistance to disease. Resolution of infection results in lifelong immunity against the disease which indicates towards the feasibility of a vaccine against the disease. Most of the vaccination studies in Leishmaniasis have been focused on promastigote- an infective stage of parasite with less exploration of pathogenic amastigote form, due to the cumbersome process of its purified isolation. In the present study, we have isolated and purified splenic amastigotes of L. donovani, following the traditional protocol with slight modification. These were fractionated into five membranous and soluble subfractions each i.e MAF1-5 and SAF1-5 and were subjected for evaluation of their ability to induce cellular responses. Out of five sub-fractions from each of membrane and soluble, only four viz. MAF2, MAF3, SAF2 and SAF3 were observed to stimulate remarkable lymphoproliferative, IFN-γ, IL-12 responses and Nitric Oxide production, in Leishmania-infected cured/exposed patients and hamsters. Results suggest the presence of Th-1 type immunostimulatory molecules in these sub-fractions which may further be exploited for developing a successful subunit vaccine from the less explored pathogenic stage against VL
Brucellosis Vaccines: Assessment of Brucella melitensis Lipopolysaccharide Rough Mutants Defective in Core and O-Polysaccharide Synthesis and Export
Background: The brucellae are facultative intracellular bacteria that cause brucellosis, one of the major neglected zoonoses. In endemic areas, vaccination is the only effective way to control this disease. Brucella melitensis Rev 1 is a vaccine effective against the brucellosis of sheep and goat caused by B. melitensis, the commonest source of human infection. However, Rev 1 carries a smooth lipopolysaccharide with an O-polysaccharide that elicits antibodies interfering in serodiagnosis, a major problem in eradication campaigns. Because of this, rough Brucella mutants lacking the O-polysaccharide have been proposed as vaccines. Methodology/Principal Findings: To examine the possibilities of rough vaccines, we screened B. melitensis for lipopolysaccharide genes and obtained mutants representing all main rough phenotypes with regard to core oligosaccharide and O-polysaccharide synthesis and export. Using the mouse model, mutants were classified into four attenuation patterns according to their multiplication and persistence in spleens at different doses. In macrophages, mutants belonging to three of these attenuation patterns reached the Brucella characteristic intracellular niche and multiplied intracellularly, suggesting that they could be suitable vaccine candidates. Virulence patterns, intracellular behavior and lipopolysaccharide defects roughly correlated with the degree of protection afforded by the mutants upon intraperitoneal vaccination of mice. However, when vaccination was applied by the subcutaneous route, only two mutants matched the protection obtained with Rev 1 albeit at doses one thousand fold higher than this reference vaccine. These mutants, which were blocked in O-polysaccharide export and accumulated internal O-polysaccharides, stimulated weak anti-smooth lipopolysaccharide antibodies. Conclusions/Significance: The results demonstrate that no rough mutant is equal to Rev 1 in laboratory models and question the notion that rough vaccines are suitable for the control of brucellosis in endemic areas.This work was funded by the European Commission (Research Contract QLK2-CT-2002-00918) and the Ministerio de Ciencia y Tecnología of Spain
(Proyecto AGL2004-01162/GAN)
Demographic, clinical and antibody characteristics of patients with digital ulcers in systemic sclerosis: data from the DUO Registry
OBJECTIVES: The Digital Ulcers Outcome (DUO) Registry was designed to describe the clinical and antibody characteristics, disease course and outcomes of patients with digital ulcers associated with systemic sclerosis (SSc).
METHODS: The DUO Registry is a European, prospective, multicentre, observational, registry of SSc patients with ongoing digital ulcer disease, irrespective of treatment regimen. Data collected included demographics, SSc duration, SSc subset, internal organ manifestations, autoantibodies, previous and ongoing interventions and complications related to digital ulcers.
RESULTS: Up to 19 November 2010 a total of 2439 patients had enrolled into the registry. Most were classified as either limited cutaneous SSc (lcSSc; 52.2%) or diffuse cutaneous SSc (dcSSc; 36.9%). Digital ulcers developed earlier in patients with dcSSc compared with lcSSc. Almost all patients (95.7%) tested positive for antinuclear antibodies, 45.2% for anti-scleroderma-70 and 43.6% for anticentromere antibodies (ACA). The first digital ulcer in the anti-scleroderma-70-positive patient cohort occurred approximately 5 years earlier than the ACA-positive patient group.
CONCLUSIONS: This study provides data from a large cohort of SSc patients with a history of digital ulcers. The early occurrence and high frequency of digital ulcer complications are especially seen in patients with dcSSc and/or anti-scleroderma-70 antibodies
Epigenetic modulators as therapeutic targets in prostate cancer
Prostate cancer is one of the most common non-cutaneous malignancies among men worldwide. Epigenetic aberrations, including changes in DNA methylation patterns and/or histone modifications, are key drivers of prostate carcinogenesis. These epigenetic defects might be due to deregulated function and/or expression of the epigenetic machinery, affecting the expression of several important genes. Remarkably, epigenetic modifications are reversible and numerous compounds that target the epigenetic enzymes and regulatory proteins were reported to be effective in cancer growth control. In fact, some of these drugs are already being tested in clinical trials. This review discusses the most important epigenetic alterations in prostate cancer, highlighting the role of epigenetic modulating compounds in pre-clinical and clinical trials as potential therapeutic agents for prostate cancer management.info:eu-repo/semantics/publishedVersio
Measurement of sigma(p(p)over-bar -> Z)center dot Br(Z ->tau tau) at root s=1.96 TeV (vol 71, art no. 072004, 2005)
A change in estimated integrated luminosity (from 226 pb^{-1}{\sigma (p \bar p \to Z) \cdot}{(Z \to \tau \tau)}209\pm13(stat.)\pm16(syst.)\pm13(lum) pb
Search for doubly charged Higgs boson pair production in the decay to mu(+)mu(+)mu(-)mu(-) in p(p)over-bar collisions at root s=1.96 TeV
A search for pair production of doubly charged Higgs bosons in the process p (p) over bar -->H++H---->mu(+)mu(+)mu(-)mu(-) is performed with the D0 run II detector at the Fermilab Tevatron. The analysis is based on a sample of inclusive dimuon data collected at an energy of roots=1.96 TeV, corresponding to an integrated luminosity of 113 pb(-1). In the absence of a signal, 95% confidence level mass limits of M(H-L(+/-+/-))>118.4 GeV/c(2) and M(H-R(+/-+/-))>98.2 GeV/c(2) are set for left-handed and right-handed doubly charged Higgs bosons, respectively, assuming 100% branching into muon pairs
Chimerism and outcomes after allogeneic hematopoietic cell transplantation following nonmyeloablative conditioning
Allogeneic hematopoietic cell transplantation ( HCT) following nonmyeloablative conditioning has been extensively evaluated in patients with hematologic malignancies who are ineligible for conventional HCT because of age or medical comorbidities. Nonmyeloablative regimens have led to an initial state of mixed hematopoietic chimerism defined as coexistence of donor- and host-derived hematopoiesis. While nonmyeloablative regimens have been associated with reduced regimen-related toxicities in comparison with conventional myeloablative conditioning, graft rejection, graft-versus-host disease ( GVHD), and disease progression have remained significant challenges. In this article, after briefly introducing current techniques for chimerism assessment, we describe factors affecting donor chimerism levels after nonmyeloablative conditioning, and then review data suggesting that chimerism assessment early after HCT might help identify patients at risk for graft rejection, GVHD and relapse/progression. Finally, we discuss how these observations have opened the way to further research protocols evaluating manipulation of postgrafting immunosuppression, and/or infusion of donor immune cells
- …