Diagnosis of recent and relapsed cases of human brucellosis by PCR assay

BACKGROUND: Brucellosis affects human populations in many developing countries including the Middle East, and Latin America where it is still endemic. It has been prevalent in Jordan for years, where 7842 cases of human brucellosis were registered at the Ministry of Health during 10 year-period. This study was initiated by the recent increase in the number of human cases diagnosed in a rural area in the Northern Jordan to help assess the status of the disease in that area. For this purpose blood specimens from brucellosis suspected cases were tested by serology, culture and PCR. METHODS: Peripheral blood specimens from 50 healthy control subjects and 165 seropositive patients having compatible signs and symptoms that were clinically diagnosed to have brucellosis were tested by blood culture, and by PCR. The PCR assay used genus-specific primers from the conserved region of the 16S rRNA sequence, which showed high specificity for the Brucella spp. RESULTS: Diagnosis of Brucella was established by PCR in 120 cases (72.7%). All of them were seropositive and 20 were positive by culture. Forty-eight of 58 (82.8%) of the relapsed cases two months after completing the treatment with an increase in the previous serological titers were positive by PCR. The assay has 85.7% positive predicative value, 100% sensitivity and specificity since it correctly identified all cases that were positive by blood cultures, 95.8% by serology and none of the control group was positive. CONCLUSIONS: Results showed that PCR assay can be applied with serology for the diagnosis of brucellosis suspected cases and relapses regardless of the duration or type of the disease without relying on the blood cultures, especially in chronic cases

Network analysis of human glaucomatous optic nerve head astrocytes

<p>Abstract</p> <p>Background</p> <p>Astrocyte activation is a characteristic response to injury in the central nervous system, and can be either neurotoxic or neuroprotective, while the regulation of both roles remains elusive.</p> <p>Methods</p> <p>To decipher the regulatory elements controlling astrocyte-mediated neurotoxicity in glaucoma, we conducted a systems-level functional analysis of gene expression, proteomic and genetic data associated with reactive optic nerve head astrocytes (ONHAs).</p> <p>Results</p> <p>Our reconstruction of the molecular interactions affected by glaucoma revealed multi-domain biological networks controlling activation of ONHAs at the level of intercellular stimuli, intracellular signaling and core effectors. The analysis revealed that synergistic action of the transcription factors AP-1, vitamin D receptor and Nuclear Factor-kappaB in cross-activation of multiple pathways, including inflammatory cytokines, complement, clusterin, ephrins, and multiple metabolic pathways. We found that the products of over two thirds of genes linked to glaucoma by genetic analysis can be functionally interconnected into one epistatic network via experimentally-validated interactions. Finally, we built and analyzed an integrative disease pathology network from a combined set of genes revealed in genetic studies, genes differentially expressed in glaucoma and closely connected genes/proteins in the interactome.</p> <p>Conclusion</p> <p>Our results suggest several key biological network modules that are involved in regulating neurotoxicity of reactive astrocytes in glaucoma, and comprise potential targets for cell-based therapy.</p

Role of toll-like receptors and their ligands in adipocyte secretion

Background: Adipose tissue is one of the main sites of energy homeostasis that regulates whole body metabolism with the help of adipokines. Disruption in its proper functioning results in adipose tissue remodeling (primarily hypertrophy and hyperplasia) which directly influences the secretion of said adipokines. Obesity characterized as chronic low-grade inflammation of the adipose tissue is one such condition that has far reaching effects on whole body metabolism. Inflammation in turn results in immune cells infiltrating into the tissue and further promoting adipocyte dysfunction. Purpose: In our study we explored this adipose tissue-innate immunity axis by differentiating adipose tissue derived stem cells (ADSCs) into white and beige adipocytes. We further stimulated our cultures with lipopolysaccharide (LPS), flagellin, or meteorin-like, glial cell differentiation regulator (METRNL) to trigger an inflammatory response. We then evaluated Toll-like receptor (TLR) mRNA expression and secretion of interleukin (IL-6), interleukin-8 (IL-8), brain-derived neurotrophic factor (BDNF), and nerve growth factor (NGF) in these cultures. Results: We found that TLR2 is the highest expressed receptor in adipocytes. Further, LPS and METRNL are strong activators of TLR2 in white and beigeBMP7(-) adipocytes. TLR4 was not significantly expressed in any of our cultures despite LPS stimulation. TLR9 expression is upregulated in ADSCs upon LPS and METRNL stimulation. IL-6 and IL-8 secretion is increased upon LPS stimulation in white adipocytes. METRNL activates both IL-6 and IL-8 expression in adipocyte cultures. Lastly, BDNF and NGF is secreted by all adipocyte cultures with beigeBMP7(-) and beigeBMP7(+) secreting slightly higher amounts in comparison to white adipocytes. Conclusion: ADSCs and adipocytes alike are capable of expressing TLRs, but white adipocytes remain the highest expressing in both control and stimulated cultures. TLR2 is highly expressed in white and beige adipocytes whereas TLR4 showed no significant expression. LPS and METRNL trigger IL-6 and IL-8 secretion in adipocytes. Products of white adipocyte &ldquo;browning&rdquo; are capable of secreting higher amounts of BDNF and NGF in comparison to white adipocytes

Synthesis and characterization of nanomaterials using microfluidic technology

Nanomaterials have attracted tremendous interest during the past two decades. Microfluidic technology offers an alternative strategy for the synthesis and characterization of nanomaterials with controlled properties. The convergence of nanomaterials and microfluidic technology affords an enormous opportunity for the further development of novel nanomaterials for various applications. This chapter covers recent achievements and the latest trends in the synthesis and characterization of nanomaterials using microfluidic technology