Primary non Hodgkin's lymphoma of the lacrimal sac

<p>Abstract</p> <p>Background</p> <p>Primary Non Hodgkin's Lymphoma (NHL) of the lacrimal sac is rare.</p> <p>Methods</p> <p>The clinical features of a 78 year old female who presented with epiphora and swelling of the left lacrimal sac are described.</p> <p>Results</p> <p>Computerised tomography showed a mass involving the left lacrimal sac. Histopathological examination revealed a diffuse large B cell NHL. Immunohistological examination demonstrated B cell origin. Chemotherapy could not be administered due to co morbid conditions. The patient was treated with radiotherapy to a dose of 45 Gy in 25 fractions. Patient is disease free and on follow up after 36 months.</p> <p>Conclusion</p> <p>Primary radiotherapy is a treatment option with curative potential for localized NHL of the lacrimal sac and may be considered in patients who cannot tolerate appropriate chemotherapy.</p

The integrated analysis of metabolic and protein interaction networks reveals novel molecular organizing principles

Background: The study of biological interaction networks is a central theme of systems biology. Here, we investigate the relationships between two distinct types of interaction networks: the metabolic pathway map and the protein-protein interaction network (PIN). It has long been established that successive enzymatic steps are often catalyzed by physically interacting proteins forming permanent or transient multi-enzymes complexes. Inspecting high-throughput PIN data, it was shown recently that, indeed, enzymes involved in successive reactions are generally more likely to interact than other protein pairs. In our study, we expanded this line of research to include comparisons of the underlying respective network topologies as well as to investigate whether the spatial organization of enzyme interactions correlates with metabolic efficiency. Results: Analyzing yeast data, we detected long-range correlations between shortest paths between proteins in both network types suggesting a mutual correspondence of both network architectures. We discovered that the organizing principles of physical interactions between metabolic enzymes differ from the general PIN of all proteins. While physical interactions between proteins are generally dissortative, enzyme interactions were observed to be assortative. Thus, enzymes frequently interact with other enzymes of similar rather than different degree. Enzymes carrying high flux loads are more likely to physically interact than enzymes with lower metabolic throughput. In particular, enzymes associated with catabolic pathways as well as enzymes involved in the biosynthesis of complex molecules were found to exhibit high degrees of physical clustering. Single proteins were identified that connect major components of the cellular metabolism and may thus be essential for the structural integrity of several biosynthetic systems. Conclusion: Our results reveal topological equivalences between the protein interaction network and the metabolic pathway network. Evolved protein interactions may contribute significantly towards increasing the efficiency of metabolic processes by permitting higher metabolic fluxes. Thus, our results shed further light on the unifying principles shaping the evolution of both the functional (metabolic) as well as the physical interaction network

Cyanobacterial lipopolysaccharides and human health – a review

Cyanobacterial lipopolysaccharide/s (LPS) are frequently cited in the cyanobacteria literature as toxins responsible for a variety of heath effects in humans, from skin rashes to gastrointestinal, respiratory and allergic reactions. The attribution of toxic properties to cyanobacterial LPS dates from the 1970s, when it was thought that lipid A, the toxic moiety of LPS, was structurally and functionally conserved across all Gram-negative bacteria. However, more recent research has shown that this is not the case, and lipid A structures are now known to be very different, expressing properties ranging from LPS agonists, through weak endotoxicity to LPS antagonists. Although cyanobacterial LPS is widely cited as a putative toxin, most of the small number of formal research reports describe cyanobacterial LPS as weakly toxic compared to LPS from the Enterobacteriaceae. We systematically reviewed the literature on cyanobacterial LPS, and also examined the much lager body of literature relating to heterotrophic bacterial LPS and the atypical lipid A structures of some photosynthetic bacteria. While the literature on the biological activity of heterotrophic bacterial LPS is overwhelmingly large and therefore difficult to review for the purposes of exclusion, we were unable to find a convincing body of evidence to suggest that heterotrophic bacterial LPS, in the absence of other virulence factors, is responsible for acute gastrointestinal, dermatological or allergic reactions via natural exposure routes in humans. There is a danger that initial speculation about cyanobacterial LPS may evolve into orthodoxy without basis in research findings. No cyanobacterial lipid A structures have been described and published to date, so a recommendation is made that cyanobacteriologists should not continue to attribute such a diverse range of clinical symptoms to cyanobacterial LPS without research confirmation

Antiviral Activity of an Ether-Extracted Nonviable Preparation of <i>Brucella abortus</i>

Extraction of living Brucella abortus (strain 456) with aqueous ether yielded a nonviable, insoluble residue (Bru-Pel). When injected into mice, Bru-Pel was an effective, nontoxic interferon stimulus. Mice pretreated with Bru-Pel were protected against challenge with otherwise lethal doses of Semliki Forest virus. Significant protection was afforded when Bru-Pel was given as many as 7 days before virus challenge. Evidence is presented dealing with the complex nature of Bru-Pel and with the possibility that the antiviral activity of Bru-Pel may be associated not only with the production of interferon, but with a general increase in the level of nonspecific resistance in animals. </jats:p

Antiviral activity of Brucella abortus preparations; separation of active components

Injection into mice of heat-killed Brucella abortus or aqueous ether-extracted B. abortus (Bru-pel) induced a "virus-type" interferon response, with peak titers at 6.5 h. The animals also were protected against challenge with otherwise lethal doses of Semliki forest virus. Extraction of either heated B. abortus or BRU-PEL with a mixture of chloroform-methanol (2:1, vol/vol) (C-M( yielded an insoluble residue (extracted cells) and a C-M extract. Neither extracted cells nor C-M extract alone induced interferon or afforded protection against Semliki forest virus infection in mice. Full interferon-inducing and protective activity was restored when extracted cells were recombined with C-M extract. C-M extract from heat-killed Escherichia coli also was effective in restoring activity to extracted Brucella cells. Neither heat-killed E. coli nor its C-M extract was active, nor was C-M estracted E. coli recombined with the C-M extract from B. abortus. These results suggest that the interferon-inducing and antiviral protective properties of B. abortus are constituted of a C-M-extractable component that is common to B. abortus and E. coli and an unextractable component that is unique to B. abortus.</jats:p