Animal Models to Study Cancer and Its Microenvironment.

Cancers are complex tissues composed by genetically altered cancer cells and stromal elements such as inflammatory/immune cells, fibroblasts, endothelial cells and pericytes, neuronal cells, and a non-cellular component, the extracellular matrix. The complex network of interactions and crosstalk established between cancer cells and the supportig cellular and non-cellular components of the microenvironment are of extreme importance for tumor initiation and progression, strongly impacting the course and the outcome of the disease. Therefore, a better understanding of the tumorigenic processes implies the combined study of the cancer cell and the biologic, chemical and mechanic constituents of the tumor microenvironment, as their concerted action plays a major role in the carcinogenic pathway and is a key determinant of the efficacy of anti-cancer treatments. The use of animal models (e.g. Mouse, Zebrafish and Drosophila) to study cancer has greatly impacted our understanding of the processes governing initiation, progression and metastasis and allowed the discovery and pre-clinical validation of novel cancer treatments as it allows to recreate tumor development in a more pathophysiologic environment.

Variation in 'fast-track' referrals for suspected cancer by patient characteristic and cancer diagnosis: evidence from 670 000 patients with cancers of 35 different sites.

BACKGROUND: In England, 'fast-track' (also known as 'two-week wait') general practitioner referrals for suspected cancer in symptomatic patients are used to shorten diagnostic intervals and are supported by clinical guidelines. However, the use of the fast-track pathway may vary for different patient groups. METHODS: We examined data from 669 220 patients with 35 cancers diagnosed in 2006-2010 following either fast-track or 'routine' primary-to-secondary care referrals using 'Routes to Diagnosis' data. We estimated the proportion of fast-track referrals by sociodemographic characteristic and cancer site and used logistic regression to estimate respective crude and adjusted odds ratios. We additionally explored whether sociodemographic associations varied by cancer. RESULTS: There were large variations in the odds of fast-track referral by cancer (P<0.001). Patients with testicular and breast cancer were most likely to have been diagnosed after a fast-track referral (adjusted odds ratios 2.73 and 2.35, respectively, using rectal cancer as reference); whereas patients with brain cancer and leukaemias least likely (adjusted odds ratios 0.05 and 0.09, respectively, for brain cancer and acute myeloid leukaemia). There were sex, age and deprivation differences in the odds of fast-track referral (P<0.013) that varied in their size and direction for patients with different cancers (P<0.001). For example, fast-track referrals were least likely in younger women with endometrial cancer and in older men with testicular cancer. CONCLUSIONS: Fast-track referrals are less likely for cancers characterised by nonspecific presenting symptoms and patients belonging to low cancer incidence demographic groups. Interventions beyond clinical guidelines for 'alarm' symptoms are needed to improve diagnostic timeliness.

Impact of systemic lupus erythematosus on oral health-related quality of life.

Oral symptoms in systemic lupus erythematosus (SLE) patients are often unexplored and affect the health-related quality of life. The aims of this study were: (a) to evaluate the oral health condition of SLE patients compared to control subjects without rheumatic diseases; (b) to determine the consequences of oral health condition in the quality of life of these two groups. Individuals with SLE ( n = 75) and without SLE ( n = 78) (control group), paired for gender and age, underwent complete oral examination. Sociodemographic and clinical information was obtained, and interviews were conducted using the Brazilian version of the oral health impact profile. The activity and damage of SLE disease were assessed, respectively, by the systemic lupus erythematosus disease activity index 2000 and the Systemic Lupus International Collaborating Clinics/American College of Rheumatology damage index for systemic lupus erythematosus. When we analysed the oral health condition and hygiene habits of the participants, SLE patients exhibited an increased number of missing teeth despite their higher frequency of tooth brushing. No significant differences were verified in other habits and clinical parameters evaluated such as smoking, flossing, salivary flux, periodontitis, decayed and filled teeth. Patients with SLE presented with worse oral health-related quality of life than controls ( P = 0.011). The significant difference was on individuals' physical disability ( P = 0.002). The determinant of the negative impact on the oral health-related quality of life was prosthesis wearing ( P < 0.05). Overall, the oral health impact profile score was higher in individuals with moderate SLE damage compared to SLE individuals with no damage ( P = 0.043). Patients with SLE had a negative impact of oral condition on their quality of life. The evaluation of the oral health-related quality of life might be useful to monitor the effects of SLE on oral condition.

Artepillin C and phenolic compounds responsible for antimicrobial and antioxidant activity of green propolis and Baccharis dracunculifolia DC.

AIMS: This study investigates the antimicrobial activity in Staphylococcus aureus isolates (methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA)) and antioxidant activity of green propolis, Baccharis dracunculifolia DC extracts and Artepillin C™. METHODS AND RESULTS: The amount of Artepillin C in different extracts was determined by high performance liquid chromatography analysis. Minimum inhibitory concentration 90 (MIC90) was determined using 40 isolates of S. aureus inoculated in Müeller-Hinton agar culture medium containing the green propolis and B. dracunculifolia DC extracts. PVEE (green propolis ethanolic extract) and BDEH (B. dracunculifolia hexanic extract) showed the greatest antimicrobial activity with MIC90 values of 246·3 and 295·5 µg ml-1 respectively. Green propolis ethanolic and hexanic extracts (PVEE and PVEH respectively) showed the greatest antioxidant activity assessed by DPPH (1,1-diphenyl-2-picryl hydrazyl radical) with IC50 values of 13·09 and 95·86 µg ml-1 respectively. CONCLUSIONS: Green propolis ethanolic displays better antimicrobial and antioxidant activities compared to other extracts. These activities may be related to the presence of Artepillin C in synergism with the other constituents of the extracts. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, the antimicrobial activity of the extracts of green propolis and B. dracunculifolia DC demonstrated in MRSA and MSSA clinical isolates indicated that they can be important tools to treat infections caused by these bacteria.

Pre-referral general practitioner consultations and subsequent experience of cancer care: evidence from the English Cancer Patient Experience Survey.

Prolonged diagnostic intervals may negatively affect the patient experience of subsequent cancer care, but evidence about this assertion is sparse. We analysed data from 73 462 respondents to two English Cancer Patient Experience Surveys to examine whether patients with three or more (3+) pre-referral consultations were more likely to report negative experiences of subsequent care compared with patients with one or two consultations in respect of 12 a priori selected survey questions. For each of 12 experience items, logistic regression models were used, adjusting for prior consultation category, cancer site, socio-demographic case-mix and response tendency (to capture potential variation in critical response tendencies between individuals). There was strong evidence (P < 0.01 for all) that patients with 3+ pre-referral consultations reported worse care experience for 10/12 questions, with adjusted odds ratios compared with patients with 1-2 consultations ranging from 1.10 (95% confidence intervals 1.03-1.17) to 1.68 (1.60-1.77), or between +1.8% and +10.6% greater percentage reporting a negative experience. Associations were stronger for processes involving primary as opposed to hospital care; and for evaluation than report items. Considering 1, 2, 3-4 and '5+' pre-referral consultations separately a 'dose-response' relationship was apparent. We conclude that there is a negative association between multiple pre-diagnostic consultations with a general practitioner and the experience of subsequent cancer care.

Multifunctional CD4⁺ T cells in patients with American cutaneous leishmaniasis.

Leishmaniasis is a group of important parasitic diseases affecting millions worldwide. To understand more clearly the quality of T helper type 1 (Th1) response stimulated after Leishmania infection, we applied a multiparametric flow cytometry protocol to evaluate multifunctional T cells induced by crude antigen extracts obtained from promastigotes of Leishmania braziliensis (LbAg) and Leishmania amazonensis (LaAg) in peripheral blood mononuclear cells from healed cutaneous leishmaniasis patients. Although no significant difference was detected in the percentage of total interferon (IFN)-γ-producing CD4(+) T cells induced by both antigens, multiparametric flow cytometry analysis revealed clear differences in the quality of Th1 responses. LbAg induced an important proportion of multifunctional CD4(+) T cells (28% of the total Th1 response evaluated), whereas LaAg induced predominantly single-positive cells (68%), and 57% of those were IFN-γ single-positives. Multifunctional CD4(+) T cells showed the highest mean fluorescence intensity (MFI) for the three Th1 cytokines assessed and MFIs for IFN-γ and interleukin-2 from those cells stimulated with LbAg were significantly higher than those obtained after LaAg stimulation. These major differences observed in the generation of multifunctional CD4(+) T cells suggest that the quality of the Th1 response induced by L. amazonensis antigens can be involved in the mechanisms responsible for the high susceptibility observed in L. amazonensis-infected individuals. Ultimately, our results call attention to the importance of studying a Th1 response regarding its quality, not just its magnitude, and indicate that this kind of evaluation might help understanding of the complex and diverse immunopathogenesis of American tegumentary leishmaniasis.

4D XCAT phantom for multimodality imaging research.

PURPOSE: The authors develop the 4D extended cardiac-torso (XCAT) phantom for multimodality imaging research. METHODS: Highly detailed whole-body anatomies for the adult male and female were defined in the XCAT using nonuniform rational B-spline (NURBS) and subdivision surfaces based on segmentation of the Visible Male and Female anatomical datasets from the National Library of Medicine as well as patient datasets. Using the flexibility of these surfaces, the Visible Human anatomies were transformed to match body measurements and organ volumes for a 50th percentile (height and weight) male and female. The desired body measurements for the models were obtained using the PEOPLESIZE program that contains anthropometric dimensions categorized from 1st to the 99th percentile for US adults. The desired organ volumes were determined from ICRP Publication 89 [ICRP, "Basic anatomical and physiological data for use in radiological protection: reference values," ICRP Publication 89 (International Commission on Radiological Protection, New York, NY, 2002)]. The male and female anatomies serve as standard templates upon which anatomical variations may be modeled in the XCAT through user-defined parameters. Parametrized models for the cardiac and respiratory motions were also incorporated into the XCAT based on high-resolution cardiac- and respiratory-gated multislice CT data. To demonstrate the usefulness of the phantom, the authors show example simulation studies in PET, SPECT, and CT using publicly available simulation packages. RESULTS: As demonstrated in the pilot studies, the 4D XCAT (which includes thousands of anatomical structures) can produce realistic imaging data when combined with accurate models of the imaging process. With the flexibility of the NURBS surface primitives, any number of different anatomies, cardiac or respiratory motions or patterns, and spatial resolutions can be simulated to perform imaging research. CONCLUSIONS: With the ability to produce realistic, predictive 3D and 4D imaging data from populations of normal and abnormal patients under various imaging parameters, the authors conclude that the XCAT provides an important tool in imaging research to evaluate and improve imaging devices and techniques. In the field of x-ray CT, the phantom may also provide the necessary foundation with which to optimize clinical CT applications in terms of image quality versus radiation dose, an area of research that is becoming more significant with the growing use of CT.

Contrasting human cytokine responses to promastigote whole-cell extract and the Leishmania analogue receptor for activated C kinase antigen of L. amazonensis in natural infection versus immunization.

It is known that the same antigen can induce different immune responses, depending upon the way that it is presented to the immune system. The objective of this study was to compare cytokine responses of peripheral blood mononuclear cells (PBMC) from cutaneous leishmaniasis patients and subjects immunized with a first-generation candidate vaccine composed of killed Leishmania amazonensis promastigotes to a whole-cell promastigote antigen extract (La) and to the recombinant protein LACK (Leishmania analogue receptor for activated C kinase), both from L. amazonensis. Thirty-two patients, 35 vaccinees and 13 healthy subjects without exposure to Leishmania, were studied. Cytokine production was assessed by enzyme-linked immunosorbent assay and enzyme-linked immunospot assay. The interferon (IFN)-gamma levels stimulated by La were significantly higher and the levels of interleukin (IL)-10 significantly lower than those stimulated by LACK in the patient group, while LACK induced a significantly higher IFN-gamma production and a significantly lower IL-10 production compared with those induced by La in the vaccinated group. LACK also induced a significantly higher frequency of IFN-gamma-producing cells than did La in the vaccinated group. The contrast in the cytokine responses stimulated by LACK and La in PBMC cultures from vaccinated subjects versus patients indicates that the human immune response to crude and defined Leishmania antigens as a consequence of immunization differs from that induced by natural infection.

Detection of Th1/Th2 cytokine signatures in yellow fever 17DD first-time vaccinees through ELISpot assay.

Immunity to yellow fever (YF) is conferred by the interplay of humoral and cellular immune response. Despite the extensive literature on the humoral immune response to the YF vaccine virus, little is known about its cellular immune response to vaccination. The analysis of cytokine production by ex-vivo antigen-stimulated T cells has been considered as a valuable tool for understanding cellular immune response. Thus, we have analyzed two T(H)1/T(H)2 signature cytokines (IFN-gamma and IL-4) from 12 healthy first-time adults vaccinated with YF17DD virus. The cells, harvested on day 0 (before vaccination) and 7, 15 and 30 days after immunization were antigen-stimulated and analyzed by ELISpot. A significant increase in the number of spot-forming cells during the response to YF 17DD live virus stimulation by ELISpot assay was observed. IFN-gamma-and IL-4-producing cells were significantly increased on the 15th day after vaccination in all volunteers. These results presented herein are important for understanding the role of cytokines in the immune response to YF 17DD virus.

A dinosaur community composition dataset for the Late Cretaceous Nemegt Basin of Mongolia.

Dinosaur community composition data for eleven fossil localities in the Late Cretaceous Nemegt Basin of Mongolia are compiled from field observations and records in the literature. Counts were generated from skeletons and represent numbers of individuals preserved in each locality. These data were used in the analyses of Funston et al. [1] "Oviraptorosaur anatomy, diversity, and ecology in the Nemegt Basin" in the Nemegt Ecosystems Special Issue of Palaeogeography, Palaeoclimatology, Palaeoecology, where the results are discussed.

First report of diffuse cutaneous leishmaniasis and Leishmania amazonensis infection in Rio de Janeiro State, Brazil.

Diffuse cutaneous leishmaniasis (DCL) is characterised by multiple and progressive cutaneous lesions, resistance to chemotherapy and Leishmania-specific T-cell anergy. We report the first autochthonous DCL case and the first human infection with Leishmania amazonensis in Rio de Janeiro State, Brazil, where only L. braziliensis is considered to be the causative agent of cutaneous leishmaniasis. Leishmania amazonensis was identified by multilocus enzyme electrophoresis and PCR-RFLP. Our case was diagnosed as DCL according to clinical, parasitological, histopathological and immunological criteria. These observations indicate that L. amazonensis is increasing its geographical distribution in Brazil, accounting for unusual clinical presentations in new transmission areas.

Warfarin related acute kidney injury: A case report.

Warfarin is an oral anticoagulant used extensively in clinical practice; However, its side-effect of causing renal damage has been recently detected. The mechanism leading to renal damage is glomerular hemorrhage and red blood cell tubular casts prothrombin time. Recently, it was found that warfarin causes renal damage in patients with chronic kidney disease and is also associated with progression of renal disease. Warfarin causing acute kidney injury in patients with normal renal function is a rare manifestation. It is important to be aware of this condition as its innocuous presence can lead to chronic kidney disease if not corrected in time. Further studies have also found that novel oral anticoagulants such as dabigatran also cause a similar syndrome and hence a new term called anticoagulant-related nephropathy is now in vogue.

New once-daily, highly effective rescue triple therapy after multiple Helicobacter pylori treatment failures: a pilot study.

BACKGROUND: Helicobacter pylori treatment failure is a growing problem in daily practice. AIM: To determine the efficacy of the combination of rabeprazole, levofloxacin and furazolidone as a rescue therapy. METHODS: Duodenal ulcer patients previously submitted, without success, to at least two H. pylori treatment regimens were included. Gastroscopy (urease test, histological examination and culture) and (13)C-urea breath test were performed. All patients received a combination of rabeprazole 20 mg, levofloxacin 500 mg and furazolidone 200 mg (two tablets) administered in a single dose in the morning for 10 days. Clinical examination and a new (13)C-urea breath test were performed 90 days after therapy. RESULTS: Twelve patients (eight females and four males), mean age 43 (30-58) years were included. Two patients failed to complete the treatment because of nausea and vomiting. Ten patients completed the study and took all the medications as advised. Culture was obtained in six patients: 100 and 83% of the samples were sensitive to furazolidone and levofloxacin, respectively. Per-protocol and intention-to-treat eradication rates were 100 and 83% (P = 0.019). CONCLUSIONS: the combination of rabeprazole, levofloxacin and furazolidone in a single daily dose for 10 days constitutes a highly-effective and low-cost alternative as a third-line therapy in patients infected with H. pylori.

Plasma hydroxy-metronidazole/metronidazole ratio in hepatitis C virus-induced liver disease.

It has been suggested that the measurement of metronidazole clearance is a sensitive method for evaluating liver function. The aim of this study was to evaluate the usefulness of plasma hydroxy-metronidazole/metronidazole ratios as indicators of dynamic liver function to detect changes resulting from the various forms of chronic hepatitis C virus (HCV) infection. A total of 139 individuals were studied: 14 healthy volunteers, 22 healthy, asymptomatic, consecutive anti-HCV-positive HCV-RNA negative subjects, 81 patients with chronic hepatitis C (49 with moderate/severe chronic hepatitis and 34 with mild hepatitis), and 20 patients with cirrhosis of the liver. HCV status was determined by the polymerase chain reaction. Plasma concentrations of metronidazole and its hydroxy-metabolite were measured by reverse-phase high-performance liquid chromatography with ultraviolet detection in a blood sample collected 10 min after the end of a metronidazole infusion. Anti-HCV-positive HCV-RNA-negative individuals demonstrated a significantly reduced capacity to metabolize intravenously infused metronidazole compared to healthy individuals (0.0478 +/- 0.0044 vs 0.0742 +/- 0.0232). Liver cirrhosis patients also had a reduced plasma hydroxy-metronidazole/metronidazole ratio when compared to the other groups of anti-HCV-positive individuals (0.0300 +/- 0.0032 vs 0.0438 +/- 0.0027 (moderate/severe chronic hepatitis) vs 0.0455 +/- 0.0026 (mild chronic hepatitis) and vs 0.0478 +/- 0.0044 (anti-HCV-positive, HCV-RNA-negative individuals)). These results suggest an impairment of the metronidazole metabolizing system induced by HCV infection that lasts after viral clearance. In those patients with chronic hepatitis C, this impairment is paralleled by progression of the disease to liver cirrhosis.

The finding of Echinostoma (Trematoda: Digenea) and hookworm eggs in coprolites collected from a Brazilian mummified body dated 600-1,200 years before present.

The identification of parasites from ancient cultures expands our list of parasites infective to extant humans. A partially mummified human body from the archeological site of Lapa do Boquete, Minas Gerais State, Brazil, was recently discovered. It was interred between 600 and 1,200 yr ago. Dietary analysis showed that the mummified body was from a society that had a mixed subsistence of agriculture and gathering of wild foods. Coprolites from the body contained numerous helminth eggs. The eggs were identified as those of Echinostoma sp. and hookworm. Hookworm infection in pre-Columbian populations is already established, but this is the first evidence of Echinostoma sp. eggs found in human coprolites. The diagnosis of a true infection, as opposed to false parasitism, is discussed. The possibility of Echinostoma ilocanum infection is discussed, as this is a common species found in humans in the Asiatic region, which could have been introduced in South America in the pre-Columbian period. Alternative possibilities are also considered, including indigenous Brazilian Echinostoma species.

Adequacy of twice weekly hemodialysis in end stage renal disease patients at a tertiary care dialysis centre.

Hemodialysis has improved the morbidity and mortality associated with end stage renal disease. In India, hemodialysis prescription is empiric, which leads to complications related to under-dialysis. Hence, adequacy of hemodialysis in Indian setting was analyzed in this study. A total of 50 patients on twice per week hemodialysis were assessed for 1 month. The number of sessions meeting standards laid out by Kidney Diseases Outcome Quality Initiatives (KDOQI) guidelines were calculated. They were divided into two groups: one in whom dialysis was monitored and session length enhanced to meet the minimum standard Kt/V of 2 and second control group; where Kt/V was not monitored. Hemoglobin (Hb) levels, albumin levels, mean arterial pressure and World Health Organization (WHO) quality of life (QoL) score were compared in the two groups after 6 months. Only 28% of hemodialysis sessions were adequate as per KDOQI guidelines. There was significant improvement in Hb levels (1.47 vs. 0.15 g/dl), mean arterial pressure levels (15.2 vs. 3.16 mm Hg), serum albumin levels (0.82 vs. 0.11 g/dl) and WHO QoL score (17.2 vs. 2.24) in study group as compared to control group. Standard Kt/V can be used as an important tool to modify twice weekly dialysis sessions to provide better QoL to the patients. However, studies with larger sample size are required to conclusively prove our results.

Characterization of a Rab11 homologue in Trypanosoma cruzi.

Vesicle trafficking between organelles occurs through fusion of donor and specific acceptor membranes. This process is highly regulated and ensures proper direction in sorting and packaging of a number of molecules in eukaryotic cells. Monomeric GTPases of the Rab family play a pivotal role in the control of membrane fusion and vesicle traffic. In this paper, we characterize a Trypanosoma cruzi Rab 11 homologue (TcRab11) that shares at, the amino acid level, 40% similarity with human rab11, Arabdopsis thaliana rab11 and yeast rab11 homologue genes. Western blot analysis, using a polyclonal rabbit antiserum raised against a synthetic peptide derived from the COOH-terminus of predicted the TcRab11 protein, reacted to a 26kDa protein. In immunofluorescence assays, TcRab 11, was shown to be expressed in epimastigote and amastigote forms, but it was absent in trypomastigotes. Interestingly, the TcRab11 product seems to be located at the reservosome complex, a site of active endocytosis and vesicle fusion present only in the epimastigote stage. Therefore, TcRab11 may represent the first molecular marker of this peculiar organelle.

Characterization of human T lymphocyte-mediated immune responses induced by a vaccine against American tegumentary leishmaniasis.

Forty-three Brazilians were immunized against American tegumentary leishmaniasis using a vaccine made of whole antigens from killed promastigotes of five American dermotropic Leishmania strains. None of the immunized subjects had a positive reaction in the Montenegro skin test (leishmanin) before vaccination, and 74% developed positive reactions in the skin test after vaccination. The proliferative responses of peripheral blood mononuclear cells (PBMC) induced by antigens from dermotropic Leishmania species were significantly higher after vaccination than before vaccination. However, with antigens from L. chagasi (a causative agent of American visceral leishmaniasis), there was no significant difference between the proliferative responses obtained before and after vaccination. Interferon-gamma was detected in the supernatants of L. braziliensis antigen-stimulated PBMC cultures after vaccination (but not before vaccination). One year after vaccination, PBMC were obtained from eight of the immunized individuals and stimulated with L. braziliensis antigens in proliferative response assays. In all cases, the majority of the responding cells were CD8+ T cells, in contrast to the results of a group of patients with active lesions of tegumentary leishmaniasis, whose L. braziliensis-reactive cells were mainly of the CD4+ T cell phenotype.

Randomized, double-blind, placebo-controlled study on the immunogenicity of the leishmanin skin test.

A positive reaction to the leishmanin skin test (LST) indicates previous contact with Leishmania antigens and is a useful criterion for the diagnosis of cutaneous leishmaniasis. In leishmaniasis vaccine trials, selection of volunteers has always been based on skin testing. During 1999 we performed a randomized controlled study in order to evaluate the immunogenicity of the LST. Fifty-nine (29 male and 30 female) healthy volunteer undergraduate students from the Medical School of Volta Redonda, Rio de Janeiro State, Brazil, with no evidence of previous infection with Leishmania, were randomly assigned into 2 groups: 29 subjects received LST and 30 received a placebo (merthiolate-phosphate-buffered saline). All volunteers received LST 41 d after the first injection of LST or placebo. Blood samples were taken immediately before the applications of LST or placebo for the assessment of Leishmania antigen-induced proliferation and cytokine production in peripheral blood mononuclear cell cultures. A significant increase in proliferative responses to L. braziliensis (P < 0.005) and L. amazonensis (P = 0.01) antigens as well as in L. braziliensis antigen-induced interferon-gamma production (P < 0.01) followed the application of LST but not the administration of the placebo. A single LST application is therefore able to induce Leishmania-specific cell-mediated immune responses. This observation should be considered in human trials of candidate vaccines against leishmaniasis.