Design of Localized Surface Plasmon Resonance (LSPR) Biosensor for Immunodiagnostic of E. coli O157:H7 Using Gold Nanoparticles Conjugated to the Chicken Antibody

E. coli O157:H7 is one of the most important pathogens in food-borne diseases and is the main cause of the pseudo pandemic development of hemorrhagic colitis and hemolytic uremic syndrome. Also E. coli O157:H7 is the most common serotype of Shiga-toxin-producing E. coli. Traditional methods for detecting E. coli O157:H7 are expensive, time-consuming, and less sensitive. A method with high sensitivity and high-resolution optical detection is utilizes the LSPR property of spherical gold nanoparticles (GNP). In this work, we constructed a novel nano-bio probe to detect E. coli O157:H7 by synthesizing citrate gold nanoparticle conjugated (non-covalent bond) with specific chicken anti-E. coli O157:H7 antibody (IgY) by changing the pH of the nanoparticles’ environment. UV-visible and DLS methods were used to confirm the bonding between the antibody and nanoparticles and the LSPR sensitivity of the nano-bio probe was evaluated by ELISA method. We could optically detect this bacterium in less than 2 h by measuring the LSPR band λ max shifts of GNPs. The sensitivity of this novel biosensor was determined by about 10 CFU/ml, using the LSPR property of spherical gold nanoparticles. So that, the LSPR λ max red shifted from 530 to 543 nm in presence of 10 CFU bacterium. In conclusion, this nano biosensor can be used to detect this important pathogen among the clinical specimens.

     

Gender Differences: Examination of the 12-Item Bem Sex Role Inventory (BSRI-12) in an Older Brazilian Population

Objectives

Although gender is often acknowledged as a determinant of health, measuring its components, other than biological sex, is uncommon. The Bem Sex Role Inventory (BSRI) quantifies self-attribution of traits, indicative of gender roles. The BSRI has been used with participants across cultures and countries, but rarely in an older population in Brazil, as we have done in this study. Our primary objective was to determine whether the BSRI-12 can be used to explore gender in an older Brazilian population.

Methods

The BSRI was completed by volunteer participants, all community dwelling adults aged 65+ living in Natal, Brazil. Exploratory factor analysis was performed, followed by a varimax rotation (orthogonal solution) for iteration to examine the underlying gender roles of feminine, masculine, androgynous and undifferentiated, and to validate the BSRI in older adults in Brazil.

Results

The 278 participants, (80 men, 198 women) were 65–99 years old (average 73.6 for men, 74.7 for women). Age difference between sexes was not significant (p = 0.22). A 12 item version of the BSRI (BSRI-12) previously validated among Spanish seniors was used and showed validity with 5 BSRI-12 items (Cronbach=0.66) loading as feminine, 6 items (Cronbach=0.51) loading onto masculine roles and neither overlapping with the category of biological sex of respondent.

Conclusions

Although the BSRI-12 appears to be a valid indicator of gender among elderly Brazilians, the gender role status identified with the BSRI-12 was not correlated with being male or female.     

Cav2.3 channels are critical for oscillatory burst discharges in the reticular thalamus and absence epilepsy

Neurons of the reticular thalamus (RT) display oscillatory burst discharges that are believed to be critical for thalamocortical network oscillations related to absence epilepsy. Ca2+-dependent mechanisms underlie such oscillatory discharges. However, involvement of high-voltage activated (HVA) Ca2+ channels in this process has been discounted. We examined this issue closely using mice deficient for the HVA Ca(v)2.3 channels. In brain slices of Ca(v)2.3?/?, a hyperpolarizing current injection initiated a low-threshold burst of spikes in RT neurons; however, subsequent oscillatory burst discharges were severely suppressed, with a significantly reduced slow afterhyperpolarization (AHP). Consequently, the lack of Ca(v)2.3 resulted in a marked decrease in the sensitivity of the animal to γ-butyrolactone-induced absence epilepsy. Local blockade of Ca(v)2.3 channels in the RT mimicked the results of Ca(v)2.3?/? mice. These results provide strong evidence that Ca(v)2.3 channels are critical for oscillatory burst discharges in RT neurons and for the expression of absence epilepsy.     

Adenosine deamination sustains dendritic cell activation in inflammation

Adenosine is a suppressive agent that protects the host from excessive tissue injury associated with strong inflammation. In tissue stress, higher levels of adenosine signal through adenosine receptors to exert strong anti-inflammatory effects, and thus protect host cells. Existing evidence also suggests that elevated adenosine potently down-regulates the activation of lymphocytes during inflammation. This notion, however, is in contrast with another basic observation that the immune system is highly activated precisely under the same circumstances against pathogens. In this study, we show that inflammatory responses of dendritic cells (DCs) are highly sensitive to adenosine suppression. However, they intrinsically carry high adenosine deaminase activity, which in turn degrades and removes adenosine from the surroundings, cutting off DCs from the suppression. This regulatory mechanism is important in DC responses to pathogen-associated molecular patterns and their activation of T cells. Our findings suggest a mechanism that DCs maintain their hyperreactive state in inflammation despite the general state of suppression, and reveal a regulatory role of adenosine deaminase in DC innate immune responses.     

microRNAs: New prognostic,diagnostic, and therapeutic biomarkers in cervical cancer

Cervical cancer is as a kind of cancer beginning from the cervix. Given that cervical cancer could be observed in women who infected with papillomavirus, regular oral contraceptives, and multiple pregnancies. Early detection of cervical cancer is one of the most important aspects of the therapy of this malignancy. Despite several efforts, finding and developing new biomarkers for cervical cancer diagnosis are required. Among various prognostic, diagnostic, and therapeutic biomarkers, miRNA have been emerged as powerful biomarkers for detection, treatment, and monitoring of response to therapy in cervical cancer. Here, we summarized various miRNAs as an employable platform for prognostic, diagnostic, and therapeutic biomarkers in the treatment of cervical cancer.