P53 and Cancer-Associated Sialylated Glycans Are Surrogate Markers of Cancerization of the Bladder Associated with Schistosoma haematobium Infection

Background

Bladder cancer is a significant health problem in rural areas of Africa and the Middle East where Schistosoma haematobium is prevalent, supporting an association between malignant transformation and infection by this blood fluke. Nevertheless, the molecular mechanisms linking these events are poorly understood. Bladder cancers in infected populations are generally diagnosed at a late stage since there is a lack of non-invasive diagnostic tools, hence enforcing the need for early carcinogenesis markers.

Methodology/Principal Findings

Forty-three formalin-fixed paraffin-embedded bladder biopsies of S. haematobium-infected patients, consisting of bladder tumours, tumour adjacent mucosa and pre-malignant/malignant urothelial lesions, were screened for bladder cancer biomarkers. These included the oncoprotein p53, the tumour proliferation rate (Ki-67>17%), cell-surface cancer-associated glycan sialyl-Tn (sTn) and sialyl-Lewis^a/x (sLe^a/sLe^x), involved in immune escape and metastasis. Bladder tumours of non-S. haematobium etiology and normal urothelium were used as controls. S. haematobium-associated benign/pre-malignant lesions present alterations in p53 and sLe^x that were also found in bladder tumors. Similar results were observed in non-S. haematobium associated tumours, irrespectively of their histological nature, denoting some common molecular pathways. In addition, most benign/pre-malignant lesions also expressed sLe^a. However, proliferative phenotypes were more prevalent in lesions adjacent to bladder tumors while sLe^a was characteristic of sole benign/pre-malignant lesions, suggesting it may be a biomarker of early carcionogenesis associated with the parasite. A correlation was observed between the frequency of the biomarkers in the tumor and adjacent mucosa, with the exception of Ki-67. Most S. haematobium eggs embedded in the urothelium were also positive for sLe^a and sLe^x. Reinforcing the pathologic nature of the studied biomarkers, none was observed in the healthy urothelium.

Conclusion/Significance

This preliminary study suggests that p53 and sialylated glycans are surrogate biomarkers of bladder cancerization associated with S. haematobium, highlighting a missing link between infection and cancer development. Eggs of S. haematobium express sLe^a and sLe^x antigens in mimicry of human leukocytes glycosylation, which may play a role in the colonization and disease dissemination. These observations may help the early identification of infected patients at a higher risk of developing bladder cancer and guide the future development of non-invasive diagnostic tests.     

A proteomics study of the induction of somatic embryogenesis in Medicago truncatula using 2DE and MALDI-TOF/TOF

Medicago truncatula is a model legume, whose genome is currently being sequenced. Somatic embryogenesis (SE) is a genotype-dependent character and not yet fully understood. In this study, a proteomic approach was used to compare the induction and expression phases of SE of both the highly embryogenic line M9-10a of M. truncatula cv. Jemalong and its non-embryogenic predecessor line, M9. The statistical analysis between the lines revealed 136 proteins with significant differential expression (P < 0.05). Of these, 5 had a presence/absence pattern in M9 vs M9-10a and 22 showed an at least twofold difference in terms of spot volume, were considered of particular relevance to the SE process and therefore chosen for identification. Spots were excised in gel digested with trypsin and proteins were identified using matrix-assisted laser desorption ionization-time of flight/time of flight. Identified proteins indicated a higher adaptability of the embryogenic line toward the stress imposed by the inducing culture conditions. Also, some proteins were shown to have a dual pattern of expression: peroxidase, pyrophosphatase and aspartate aminotransferase. These proteins showed higher expression during the induction phases of the M9 line, whereas in the embryogenic line had higher expression at stages coinciding with embryo formation.     

Dermatophyte–host relationship of a murine model of experimental invasive dermatophytosis

Recognizing the invasive potential of the dermatophytes and understanding the mechanisms involved in this process will help with disease diagnosis and with developing an appropriate treatment plan. In this report, we present the histopathological, microbiological and immunological features of a model of invasive dermatophytosis that is induced by subcutaneous infection of Trichophyton mentagrophytes in healthy adult Swiss mice. Using this model, we observed that the fungus rapidly spreads to the popliteal lymph nodes, spleen, liver and kidneys. Similar to the human disease, the lymph nodes were the most severely affected sites. The fungal infection evoked acute inflammation followed by a granulomatous reaction in the mice, which is similar to what is observed in patients. The mice were able to mount a Th1-polarized immune response and displayed IL-10-mediated immune regulation. We believe that the model described here will provide valuable information regarding the dermatophyte–host relationship and will yield new perspective for a better understanding of the immunological and pathological aspects of invasive dermatophytosis.     

An agar-overlay method for detection of toxins produced by Escherichia coli

Abstract An agar overlay method, with Vero and Hela cells, was used for detection of heat-labile enterotoxin and verotoxin from Escherichia coli . The method is more sensitive than the conventional cell culture assay, is rapid, easy to perform, and is suitable for epidemiological studies.     

Impact of a structured multicomponent educational intervention program on metabolic control of patients with type 2 diabetes

Background

Diabetes is one of the most common metabolic disorders, with a high prevalence of patients with poor metabolic control. Worldwide, evidence highlights the importance of developing and implementing educational interventions that can reduce this burden. The main objective of this study was to analyse the impact of a lifestyle centred intervention on glycaemic control of poorly controlled type 2 diabetic patients, followed in a Community Care Centre.

Methods

A type 2 experimental design was conducted over 6 months, including 122 adults with HbA1c?≥?7.5%, randomly allocated into Experimental group (EG) or Control Group (CG). EG patients attended a specific Educational Program while CG patients frequented usual care. Personal and health characterization variables, clinical metrics and self-care activities were measured before and after the implementation of the intervention. Analysis was done by comparing gains between groups (CG vs EG) through differential calculations (post minus pre-test results) and Longitudinal analysis.

Results

Statistical differences were obtained between groups for HbA1c and BMI: EG had a decrease in 11% more (effect-size r2?=?.11) than CG for HbA1c (p?<?.001) and 4% more (effect-size r2?=?.04) in BMI (p?<?.05). When controlling for socioeconomic characteristics and comorbidities that showed to be associated to each parameter in pre-test, from pre to post-test only EG participants significantly decreased HbA1c [Wilks’ ??=?.702; F(1,57)?=?24.16; p?<?.001; ηp2?=?.298; observed power?=?.998]; BMI values [Wilks’ ??=?.900; F(1,59)?=?6.57; p?=?.013; ηp2?=?.100; observed power?=?.713]; systolic Blood pressure [Wilks’ ??=?.735; F(1,61)?=?21.94; p?<?.001; ηp2?=?.265; observed power?=?.996] and diastolic Blood pressure [Wilks’ ??=?.795; F(1,59)?=?15.20; p?<?.001; ηp2?=?.205; observed power?=?.970].

Conclusions

The impact of a structured multicomponent educational intervention program by itself, beyond standard educational approach alone, supported in a Longitudinal analysis that controlled variables statistically associated with clinical metrics in pre-test measures, has demonstrated its effectiveness in improving HbA1c, BMI and Blood pressure values.

Trial registration

RBR-8ns8pb. (Retrospectively registered: October 30,2017).

     

Relationship of sertoli-sertoli tight junctions to ectoplasmic specialization in conventional and en face views

Ectoplasmic specializations are actin filament-endoplasmic reticulum complexes that occur in Sertoli cells at sites of intercellular attachment. At sites between inter-Sertoli cell attachments, near the base of the cells, the sites are also related to tight junctions. We studied the characteristics of ectoplasmic specializations from six species using conventional views in which thin sections were perpendicular to the plane of the membranes, we used rare views in which the sections were in the plane of the membrane (en face views), and we also used the freeze-fracture technique. Tissues postfixed by osmium ferrocyanide showed junctional strands (fusion points between membranes) and actin bundles, actin sheets, or both, which could be visualized simultaneously. En face views demonstrated that the majority of tight junctional strands ran parallel to actin filament bundles. Usually, two tight junctional strands were associated with each actin filament bundle. Parallel tight junctions were occasionally extremely close together ( approximately 12 nm apart). Tight junctional strands were sometimes present without an apparent association with organized actin bundles or they were tangential to actin bundles. En face views showed that gap junctions were commonly observed intercalated with tight junction strands. The results taken together suggest a relationship of organized actin with tight junction complexes. However, the occasional examples of tight junction complexes being not perfectly aligned with actin filament bundles suggest that a precise and rigidly organized actin-tight junction relationship described above is not absolutely mandatory for the presence or maintenance of tight junctions. Species variations in tight junction organization are also presented.     

A rapid and simple method for constructing stable mutants of <Emphasis Type="Italic">Acinetobacter baumannii</Emphasis>

Background  

Acinetobacter baumannii is a multidrug-resistant bacterium responsible for nosocomial infections in hospitals worldwide. Study of mutant phenotypes is fundamental for understanding gene function. The methodologies developed to inactivate A. baumannii genes are complicated and time-consuming; sometimes result in unstable mutants, and do not enable construction of double (or more) gene knockout mutant strains of A. baumannii.     

Influence of Parasite Load on Renal Function in Mice Acutely Infected with Trypanosoma cruzi

Background

Chagas disease is a neglected tropical disease caused by Trypanosoma cruzi. Despite the vast number of studies evaluating the pathophysiological mechanisms of the disease, the influence of parasite burden on kidney lesions remains unclear. Thus, the main goal of this work was to evaluate the effect of T. cruzi infection on renal function and determine whether there was a correlation between parasite load and renal injury using an acute experimental model of the disease.

Methodology/Principal Findings

Low, medium and high parasite loads were generated by infecting C57BL/6 mice with 300 (low), 3,000 (medium) or 30,000 (high) numbers of “Y” strain trypomastigotes. We found that mice infected with T. cruzi trypomastigotes show increased renal injury. The infection resulted in reduced urinary excretion and creatinine clearance. We also observed a marked elevation in the ratio of urine volume to kidney and body weight, blood urea nitrogen, chloride ion, nitric oxide, pro- and anti-inflammatory cytokines and the number of leukocytes in the blood and/or renal tissues of infected mice. Additionally, we observed the presence of the parasite in the cortical/medullary and peri-renal region, an increase of inflammatory infiltrate and of vascular permeability of the kidney. Overall, most renal changes occurred mainly in animals infected with high parasitic loads.

Conclusions/Significance

These data demonstrate that T. cruzi impairs kidney function, and this impairment is more evident in mice infected with high parasitic loads. Moreover, these data suggest that, in addition to the extensively studied cardiovascular effects, renal injury should be regarded as an important indicator for better understanding the pan-infectivity of the parasite and consequently for understanding the disease in experimental models.