Divergence of canonical danger signals: The genome-level expression patterns of human mononuclear cells subjected to heat shock or lipopolysaccharide

Background

Peripheral blood mononuclear cells (PBMC) serve a sentinel role allowing the host to efficiently sense and adapt to the presence of danger signals. Herein we have directly compared the genome-level expression patterns (microarray) of a human PBMC model (THP-1 cells) subjected to one of two canonical danger signals, heat shock or lipopolysaccharide (LPS).

Results and Discussion

Based on sequential expression and statistical filters, and in comparison to control cells, we found that 3,988 genes were differentially regulated in THP-1 cells subjected to LPS stress, and 2,921 genes were differentially regulated in THP-1 cells subjected to heat shock stress. Venn analyses demonstrated that the majority of differentially regulated genes (≥ 70%) were uniquely expressed in response to one of the two danger signals. Functional analyses demonstrated that the two danger signals induced expression or repression of genes corresponding to unique pathways, molecular functions, biological processes, and gene networks. In contrast, there were 184 genes that were commonly upregulated by both stress signals, and 430 genes that were commonly downregulated by both stress signals. Interestingly, the 184 commonly upregulated genes corresponded to a gene network broadly related to inflammation, and more specifically to chemokine signaling.

Conclusion

These data demonstrate that the mononuclear cell responses to the canonical stress signals, heat shock and LPS, are highly divergent. However, there is a heretofore unrecognized common pattern of gene network expression corresponding to chemokine-related biology. The data also serve as a reference database for investigators in the field of stress signaling.     

Vector Databank in the Indian Armed Forces

Background

Medical intelligence of disease vectors deals with understanding vector distribution and control.

Methods

An entomological baseline survey using standard vector sampling techniques was done as a pilot study to map the vectors of defence importance in two cantonments of Pune with a view to establish a vector databank and impart training to armed forces personnel in vector surveillance.

Result

The project trained 142 armed forces personnel in surveillance techniques in three years. Seventeen species of mosquitoes comprising of eight vector species were collected. Three other vectors viz. Rhipicephalus sanguineus, Xenopsylla cheopis and Leptotrombidium deliense are reported.

Conclusion

The study emphasizes the need for vector mapping /surveillance in each area for preventing morbidity and mortality amongst troops. It also focuses on indigenous fabrication of vector sampling tools and training of personnel for capacity building which in turn will enable such surveys to be undertaken in other units and deployment areas.Key Words: Leptotrombidium, Mosquitoes, Rhipicephalus, Surveillance, Xenopsylla     

Needle biopsy of renal allografts: comparison of two techniques

Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications.     

Mutations in the Ca(2+)-sensing receptor gene cause autosomal dominant and sporadic hypoparathyroidism

Parathyroid hormone secretion is negatively regulated by a 7- transmembrane domain, G-protein coupled Ca(2+)-sensing receptor. We hypothesized that activating mutations in this receptor might cause autosomal dominant hypoparathyroidism (ADHP). Consistent with this hypothesis, we identified, in two families with ADHP, heterozygous missense mutations in the Ca(2+)-sensing receptor gene that cosegregated with the disorder. None of 50 normal controls had either mutation. We also identified a de novo, missense Ca(2+)-sensing receptor mutation in a child with severe sporadic hypoparathyroidism. The amino acid substitution in one ADHP family affected the N-terminal, extracellular domain of the receptor. The other mutations involved the transmembrane region. Unlike patients with acquired hypoparathyroidism, patients with these mutations had hypercalciuria even at low serum calcium concentrations. Their greater hypercalciuria presumably reflected activation of Ca(2+)-sensing receptors in kidney cells, where the receptor negatively regulates calcium reabsorption. This augmented hypercalciuria increases the risk of renal complications and thus has implications for the choice of therapy.      

Accelerated apoptosis and low Bcl-2 expression associated with neuroendocrine differentiation predict shortened survival in operated large cell carcinoma of the lung

In order to test the hypothesis that increased apoptotic activity is connected with neuroendocrine differentiation and low differentiation degree in large cell carcinoma (LCLC) and is regulated by bcl-2 family proteins, we analysed the extent of apoptosis and tumor necrosis and their relation to the expression of bcl-2, bax, bak and mcl-1 in 35 LCLCs, of which 20 were classified as large cell neuroendocrine lung carcinomas (LCNEC) and 15 as large cell non-neuroendocrine lung carcinomas (LCNNEC). The extent of apoptosis was determined by detecting and counting the relative and absolute numbers of apoptotic cells and bodies using in situ 3′-end labelling of the apoptotic DNA. The extent and intensity of expression of the bcl-2, bax, bak and mcl-1 proteins were studied by immunohistochemistry. Also the relative volume density of necrosis was evaluated and correlated with the other parameters. Finally, all the parameters were evaluated as prognostic markers and correlated with data on the survival of the patients. Relatively high apoptotic indices were seen in both tumor types (average for both 2.53%, range 0.09–27.01%). Significantly higher bcl-2 and bak indices were detected more often in LCNECs than in LCNNECs. Immunohistochemically detected bax, bcl-2 and bak expression was independent of apoptotic index in both tumor types, while there was a statistically significant positive association between mcl-1 expression and apoptotic index in LCNNEC but not in LCNEC. There was a statistically significant association between high apoptotic index and shortened survival in LCLC. However, no association was found between tumor stage and apoptosis. The patients with LCNEC and low bcl-2 protein expression had a significantly shorter survival time than those with high bcl-2 indices. There was also a clear association between shortened survival and necrotic LCNNEC. LCLCs show relatively high apoptotic activity, which is associated with shortened survival. The expression of bcl-2, bak and mcl-1 is associated with neuroendocrine differentiation in LCLC. Finally, our results support some previous reports suggesting that bcl-2 expression in combination with some other markers involved in apoptosis and/or proliferation may be of prognostic value in cases of lung carcinoma with neuroendocrine differentiation. 179-186, 1999)