Isolation of a human serum protein that inhibits the growth of Cryptococcus neoformans

Human serum at 5 to 10% (v/v) in tissue culture medium RPMI-1640, inhibits the growth of Cryptococcus neoformans by 80 to 93%. Serum fractionated on molecular sieve columns (Sephadex G-200) yielded an active protein fraction. This fraction at 100 μg protein/ml inhibited the growth of C. neoformans by 54%. When an active G-200 fraction was applied to a dye affinity column (Affi-Gel Blue) the fraction with inhibitory activity was bound by the column and was eluted with 1.4 M NaCl in 0.1 M phosphate buffer (pH 7.4). The bound fraction at 62.5 μg protein/ml inhibited C. neoformans growth by 82%. On native polyacrylamide gel electrophoresis (Nu-PAGE) the bound fraction migrated as a major and a minor band. Under the reducing conditions of sodium dodecyl sulfate (SDS)-PAGE the bound fraction yielded 4 prominent bands with MW ranging from 175 kDa to 45 kDa. Purification of the active Sephadex G-200 peak was achieved using an anion exchange column (DEAE-Sephacel). Protein eluted with 0.1 M NaCl had strong anticryptococcal activity (12.5 μg/ml, 79% inhibition), which in SDS-PAGE migrated as a single band with an approximate MW of 85 kDA. This protein appears important in natural host resistance to C. neoformans and polymorphisms or deficiencies may have epidemiologic and diagnostic relevance. This revised version was published online in August 2006 with corrections to the Cover Date.     

Human palatine tonsil: a new potential tissue source of multipotent mesenchymal progenitor cells

Introduction  

Mesenchymal progenitor cells (MPCs) are multipotent progenitor cells in adult tissues, for example, bone marrow (BM). Current challenges of clinical application of BM-derived MPCs include donor site morbidity and pain as well as low cell yields associated with an age-related decrease in cell number and differentiation potential, underscoring the need to identify alternative sources of MPCs. Recently, MPC sources have diversified; examples include adipose, placenta, umbilicus, trabecular bone, cartilage, and synovial tissue. In the present work, we report the presence of MPCs in human tonsillar tissue.     

Monitoring the organization and dynamics of bovine hippocampal membranes utilizing differentially localized fluorescent membrane probes

Previous work from our laboratory has established bovine hippocampal membranes as a convenient natural source for studying neuronal receptors such as the G-protein coupled serotonin1A receptor. In this paper, we have explored the organization and dynamics of bovine hippocampal membranes using environment-sensitive and differentially localized fluorescent probes NBD-PE and NBD-cholesterol, utilizing wavelength-selective and time-resolved fluorescence measurements. The NBD group in NBD-PE is localized at the membrane interface while in NBD-cholesterol it is localized deeper in the membrane. Our results show that native hippocampal membranes offer considerable motional restriction as evidenced from red edge excitation shift of NBD probes. However, this effect progressively decreases with increasing cholesterol depletion in the case of NBD-cholesterol, possibly indicating a reduction in membrane heterogeneity. In contrast, REES of NBD-PE in hippocampal membranes does not show any significant change upon cholesterol depletion indicating relative lack of sensitivity of the membrane interface to cholesterol depletion. These observations are supported by changes in fluorescence polarization with cholesterol depletion. Taken together, these results imply that the deeper hydrocarbon region of the hippocampal membrane is more sensitive to changes in membrane organization and dynamics due to cholesterol depletion than the interfacial region. The motional restriction in native membranes is maintained even in the absence of proteins. The fluorescence lifetimes of both the NBD probes show slight reduction upon cholesterol depletion indicating a change in micro-environmental polarity possibly due to water penetration. These results are relevant in understanding the complex organization of hippocampal membranes and could have possible functional implications.     

A novel class of anti-IL-12p40 antibodies: Potent neutralization via inhibition of IL-12-IL-12Rβ2 and IL-23-IL-23R

While current therapeutic antibodies bind to IL-12 and IL-23 and inhibit their binding to IL-12Rβ1, we describe a novel antibody, termed 6F6, that binds to IL-12 and IL-23 and inhibits the interaction of IL-12 and IL-23 with their cognate signaling receptors IL-12Rβ2 and IL23R. This antibody does not affect the natural inhibition of the IL-12/23 pathway by the antagonists monomeric IL-12p40 and IL-12p80 respectively, which suggests that a dual antagonist system is possible. We have mapped the epitope of 6F6 to domain 3 of the p40 chain common to IL-12 and IL-23 and demonstrate that an antibody bound to this epitope is sufficient to inhibit engagement of the signaling receptors. Antibodies with this unique mechanism of inhibition are potent inhibitors of IL-12 induced IFNγ production and IL-23 induced IL-17 production in vitro, and in an in vivo model of psoriasis, treatment with a humanized variant of this antibody, h6F6, reduced the inflammatory response, resulting in decreased epidermal hyperplasia. We believe that this new class of IL-12/23 neutralising antibodies has the potential to provide improved potency and efficacy as anti-inflammatory agents, particularly in diseases characterized by an overproduction of IL-12.Key words: IL-12, IL-23, IL-12p40, IL-12 receptor, IL-12Rβ1, IL-12Rβ2, IL-23R, antibody, TH17, TH1     

Role of anoctamins in cancer and apoptosis

Anoctamin 1 (TMEM16A, Ano1) is a recently identified Ca²⁺-activated chloride channel and a member of a large protein family comprising 10 paralogues. Before Ano1 was identified as a chloride channel protein, it was known as the cancer marker DOG1. DOG1/Ano1 is expressed in gastrointestinal stromal tumours (GIST) and particularly in head and neck squamous cell carcinoma, at very high levels never detected in other tissues. It is now emerging that Ano1 is part of the 11q13 locus, amplified in several types of tumour, where it is thought to augment cell proliferation, cell migration and metastasis. Notably, Ano1 is upregulated through histone deacetylase (HDAC), corresponding to the known role of HDAC in HNSCC. As Ano1 does not enhance proliferation in every cell type, its function is perhaps modulated by cell-specific factors, or by the abundance of other anoctamins. Thus Ano6, by regulating Ca²⁺-induced membrane phospholipid scrambling and annexin V binding, supports cellular apoptosis rather than proliferation. Current findings implicate other cellular functions of anoctamins, apart from their role as Ca²⁺-activated Cl⁻ channels.     

Quantifying fall migration of Ross’s gulls (Rhodostethia rosea) past Point Barrow,Alaska

The Ross’s gull (Rhodostethia rosea) is a poorly known seabird of the circumpolar Arctic. The only place in the world where Ross’s gulls are known to congregate is in the near-shore waters around Point Barrow, Alaska, where they undertake an annual passage in late fall. Ross’s gulls seen at Point Barrow are presumed to originate from nesting colonies in Siberia, but neither their origin nor their destination has been confirmed. Current estimates of the global population of Ross’s gulls are based largely on expert opinion, and the only reliable population estimate is derived from extrapolations from previous counts conducted at Point Barrow, but these data are now over 25 years old. In order to update and clarify the status of this species in Alaska, our study quantified the timing, number, and flight direction of Ross’s gulls passing Point Barrow in 2011. We recorded up to two-thirds of the estimated global population of Ross’s gulls (≥27,000 individuals) over 39 days with numbers peaking on 16 October when we observed over 7,000 birds during a 3-h period.     

Ca2+-binding Motif of βγ-Crystallins

βγ-Crystallin-type double clamp (N/D)(N/D)XX(S/T)S motif is an established but sparsely investigated motif for Ca²⁺ binding. A βγ-crystallin domain is formed of two Greek key motifs, accommodating two Ca²⁺-binding sites. βγ-Crystallins make a separate class of Ca²⁺-binding proteins (CaBP), apparently a major group of CaBP in bacteria. Paralleling the diversity in βγ-crystallin domains, these motifs also show great diversity, both in structure and in function. Although the expression of some of them has been associated with stress, virulence, and adhesion, the functional implications of Ca²⁺ binding to βγ-crystallins in mediating biological processes are yet to be elucidated.     

Decreasing mortality and hospitalizations with rising costs related to gastric cancer in the USA: an epidemiological perspective

Background

There is no convincing data on the trends of hospitalizations, mortality, cost, and demographic variations associated with inpatient admissions for gastric cancer in the USA. The aim of this study was to use a national database of US hospitals to evaluate the trends associated with gastric cancer.

Methods

We analyzed the National Inpatient Sample (NIS) database for all patients in whom gastric cancer (ICD-9 code: 151.0, 151.1, 151.2, 151.3, 151.4, 151.5, 151.6, 151.8, 151.9) was the principal discharge diagnosis during the period, 2003–2014. The NIS is the largest publicly available all-payer inpatient care database in the US. It contains data from approximately eight million hospital stays each year. The statistical significance of the difference in the number of hospital discharges, length of stay, and hospital costs over the study period was determined by regression analysis.

Results

In 2003, there were 23,921 admissions with a principal discharge diagnosis of gastric cancer as compared to 21,540 in 2014 (P?<?0.01). The mean length of stay for gastric cancer decreased by 17% between 2003 and 2014 from 10.9?days to 8.95?days (P?<?0.01). However, during this period, the mean hospital charges increased significantly by 21% from $ 75,341 per patient in 2003 to $ 91,385 per patient in 2014 (P?<?0.001). There was a more significant reduction in mortality over a period of 11?years from 2428 (10.15%) in 2003 to 1345 (6.24%) in 2014 (P?<?0.01). The aggregate charges (i.e., “national bill”) for gastric cancer increased significantly from 1.79 bn $ to 1. 96 bn $ (P?<?0.001), despite decrease in hospitalization (inflation adjusted).

Conclusion

Although the number of inpatient admissions for gastric cancer have decreased over the past decade, the healthcare burden and cost related to it has increased significantly. Inpatient mortality is decreasing which is consistent with overall decrease in gastric cancer-related deaths. Cost increase associated with gastric cancer contributed significantly to the national healthcare bill.