Genetic identification of antagonistically active lactobacillus strains isolated from the oral cavity of healthy individuals

Examination of dental deposits from 45 healthy individuals detected 3 lactobacillus strains showing a high antagonism toward test cultures. The api 50 CH "bio Merieux" test systems were employed to identify strains as Lactobacillus fermentum 39, Lactobacillus rhamnosus 24 and Lactobacillus paracasei 50. The results of analyzing the sequences of the 16S rRNA genes of the test strains confirmed this identification, except for the latter strain. The taxonomic status of the third strain L. rhamnosus 50 was determined by the bioinformative analysis of the nucleotide sequence of the 16S rRNA genes.     

Association of interferon lambda-4 rs12979860 polymorphism with hepatocellular carcinoma in patients with chronic hepatitis C infection

BACKGROUND Hepatitis C virus(HCV) infection is a public health concern worldwide.Several factors,including genetic polymorphisms,may be evolved in the progression of HCV infection to liver diseases.Interferon lambdas(IFNLs) modulate the immune response during viral infections.IFNLs induce antiviral activity,interfering in the viral replication by promoting the expression of several genes that regulate immunological functions.The interferon lambda-4(IFNL4) rs12979860 polymorphism,which is characterized by a C to T transition in intron 1,is associated with spontaneous and treatment-induced clearance of HCV infection and may play a role in the development of HCV-associated liver diseases,including hepatocellular carcinoma(HCC).AIM To investigate the association of IFNL4 rs12979860 polymorphism with fibrosis,cirrhosis,and HCC in patients with chronic HCV infection.METHODS This study was comprised of 305 chronic HCV-infected patients(53 fibrosis,154 cirrhosis,and 98 HCC cases).The control group was comprised of 260 HCVnegative healthy individuals.The IFNL4 rs12979860 polymorphism was genotyped using the TaqMan assay.Fibrosis was diagnosed based on liver biopsy findings,while cirrhosis was diagnosed through clinical,laboratory,anatomopathological,and/or imaging data.HCC was diagnosed through imaging tests,tumor,and/or anatomopathological markers.RESULTS The T allele was observed in the three groups of patients(fibrosis,cirrhosis,and HCC) at a significantly higher frequency when compared with the control group(P=0.047,P 0.001,and P=0.01,respectively).Also,genotype frequencies presented significant differences between the control group and cirrhosis patients(P 0.001) as well as HCC patients(P=0.002).The risk analysis was performed using the codominant and dominant T allele models.In the codominant model,it was observed that the CT genotype showed an increased risk of developing cirrhosis in comparison with the CC genotype [odds ratio(OR)=2.53;95%confidence interval(CI):1.55-4.15;P 0.001] as well as with HCC(OR=2.54;95%CI:1.44-4.56;P=0.001).A similar result was observed in the comparison of the TT vs CC genotype between the control group and cirrhosis group(OR=2.88;95 % CI:1.44-5.77;P=0.001) but not for HCC patients.In the dominant T allele model,the CT+TT genotypes were associated with an increased risk for progression to cirrhosis(OR=2.60;95%CI:1.63-4.19;P 0.001) and HCC(OR=2.45;95%CI:1.42-4.31;P=0.001).CONCLUSION These findings suggest that the T allele of IFNL4 rs12979860 polymorphism is associated with the development of cirrhosis and HCC in chronic HCV-infected patients.     

Chronic treatment with anabolic steroids induces ventricular repolarization disturbances: Cellular, ionic and molecular mechanism

The illicit use of supraphysiological doses of androgenic steroids (AAS) has been suggested as a cause of arrhythmia in athletes. The objectives of the present study were to investigate the time-course and the cellular, ionic and molecular processes underlying ventricular repolarization in rats chronically treated with AAS. Male Wistar rats were treated weekly for 8 weeks with 10 mg/kg of nandrolone decanoate (DECA n = 21) or vehicle (control n = 20). ECG was recorded weekly. Action potential (AP) and transient outward potassium current (I_to) were recorded in rat hearts. Expression of KChIP2, Kv1.4, Kv4.2, and Kv4.3 was assessed by real-time PCR. Hematoxylin/eosin and Picrosirius red staining were used for histological analysis. QTc was greater in the DECA group. After DECA treatment the left, but not right, ventricle showed a longer AP duration than did the control. I_to current densities were 47.5% lower in the left but not in the right ventricle after DECA. In the right ventricle the I_to inactivation time-course was slower than in the control group. After DECA the left ventricle showed lower KChIP2 (∼ 26%), Kv1.4 (∼ 23%) and 4.3 (∼ 70%) expression while the Kv 4.2 increased in 4 (∼ 250%) and diminished in 3 (∼ 30%) animals of this group. In the right ventricle the expression of I_to subunits was similar between the treatment and control groups. DECA-treated hearts had 25% fewer nuclei and greater nuclei diameters in both ventricles. Our results strongly suggest that supraphysiological doses of AAS induce morphological remodeling in both ventricles. However, the electrical remodeling was mainly observed in the left ventricle.     

Immunomorphological characteristics of mucosal and endocrine cells of the colon in patients with chronic ulcerative colitis

Morphological methods were used for the study of epithelial-stromal relations, free cells, lymphocyte population and endocrine cells of the colon during the stage of remission andexacerbation in patients with nonspecific ulcerative colitis (NUC). An increase of the total population of endocrine cells (with domination of serotonin-containing cells) in all altered parts of the colon was in chronic NUC. Disturbance of cooperation between the free stromal cells and epithelial components, correlation between population of T and B lymphocytes, increased number of CD8+ cells were seen in NUC exacerbation this being the basis of chronization and progression of this disease.     

Bone marrow mesenchymal stromal cells rescue cardiac function in streptozotocin-induced diabetic rats

Objectives

In the present study, we investigated whether MSC-transplantation can revert cardiac dysfunction in streptozotocin-induced diabetic rats and the immunoregulatory effects of MSC were examined.

Background

Cardiac complications are one of the main causes of death in diabetes. Several studies have shown anti-diabetic effects of bone marrow mesenchymal stromal cells (MSC).

Methods/results

The rats were divided in three groups: Non-diabetic, Diabetic and Diabetic-Treated with 5 × 10⁶ MSC 4 weeks after establishment of diabetes. Four weeks after MSC-therapy, systemic metabolic parameters, immunological profile and cardiac function were assessed. MSC-transplantation was able to revert the hyperglycemia and body weight loss of the animals. In addition, after MSC-transplantation a decrease in corticosterone and IFN-γ sera levels without restoration of insulin and leptin plasma levels was observed. Also, MSC-therapy improved electrical remodeling, shortening QT and QTc in the ECG and action potential duration of left ventricular myocytes. No arrhythmic events were observed after MSC-transplantation. MSC-therapy rescued the cardiac beta-adrenergic sensitivity by increasing beta-1 adrenergic receptor expression. Both alpha and beta cardiac AMPK and p-AMPK returned to baseline values after MSC-therapy. However, total ERK1 and p-ERK1/2 were not different among groups.

Conclusion

The results indicate that MSC-therapy was able to rescue cardiac impairment induced by diabetes, normalize cardiac AMPK subunit expression and activity, decrease corticosterone and glycemia and exert systemic immunoregulation.     

Blind source separation of ex-vivo aorta tissue multispectral images

Blind Source Separation methods (BSS) aim for the decomposition of a given signal in its main components or source signals. Those techniques have been widely used in the literature for the analysis of biomedical images, in order to extract the main components of an organ or tissue under study. The analysis of skin images for the extraction of melanin and hemoglobin is an example of the use of BSS. This paper presents a proof of concept of the use of source separation of ex-vivo aorta tissue multispectral Images. The images are acquired with an interference filter-based imaging system. The images are processed by means of two algorithms: Independent Components analysis and Non-negative Matrix Factorization. In both cases, it is possible to obtain maps that quantify the concentration of the main chromophores present in aortic tissue. Also, the algorithms allow for spectral absorbance of the main tissue components. Those spectral signatures were compared against the theoretical ones by using correlation coefficients. Those coefficients report values close to 0.9, which is a good estimator of the method’s performance. Also, correlation coefficients lead to the identification of the concentration maps according to the evaluated chromophore. The results suggest that Multi/hyper-spectral systems together with image processing techniques is a potential tool for the analysis of cardiovascular tissue.OCIS codes: (000.1430) Biology and medicine, (000.2170) Equipment and techniques, (110.4234) Multispectral and hyperspectral imaging, (170.3880) Medical and biological imaging, (170.4580) Optical diagnostics for medicine, (170.6935) Tissue characterization     

Characterization of LGALS3 (galectin-3) as a player in DNA damage response

DNA damage repair (DDR) is an orchestrated process encompassing the injury detection to its complete resolution. DNA double-strand break lesions are repaired mainly by two distinct mechanisms: the error-free homologous recombination (HR) and the error-prone non-homologous end-joining. Galectin-3 (GAL3) is the unique member of the chimeric galectins subfamily and is reported to be involved in several cancer development and progression related events. Recently our group described a putative protein interaction between GAL3 and BARD1, the main partner of breast and ovarian cancer susceptibility gene product BRCA1, both involved in HR pathway. In this report we characterized GAL3/BARD1 protein interaction and evaluated the role of GAL3 in DDR pathways using GAL3 silenced human cells exposed to different DNA damage agents. In the absence of GAL3 we observed a delayed DDR response activation, as well as a decrease in the G₂/M cell cycle checkpoint arrest associated with HR pathway. Moreover, using a TAP-MS approach we also determined the protein interaction network of GAL3.