Modulation of Intracellular Calcium Levels by Calcium Lactate Affects Colon Cancer Cell Motility through Calcium-Dependent Calpain

Cancer cell motility is a key phenomenon regulating invasion and metastasis. Focal adhesion kinase (FAK) plays a major role in cellular adhesion and metastasis of various cancers. The relationship between dietary supplementation of calcium and colon cancer has been extensively investigated. However, the effect of calcium (Ca²⁺) supplementation on calpain-FAK-motility is not clearly understood. We sought to identify the mechanism of FAK cleavage through Ca²⁺ bound lactate (CaLa), its downstream signaling and role in the motility of human colon cancer cells. We found that treating HCT116 and HT-29 cells with CaLa immediately increased the intracellular Ca²⁺ (iCa²⁺) levels for a prolonged period of time. Ca²⁺ influx induced cleavage of FAK into an N-terminal FAK (FERM domain) in a dose-dependent manner. Phosphorylated FAK (p-FAK) was also cleaved in to its p-N-terminal FAK. CaLa increased colon cancer cells motility. Calpeptin, a calpain inhibitor, reversed the effects of CaLa on FAK and pFAK cleavage in both cancer cell lines. The cleaved FAK translocates into the nucleus and modulates p53 stability through MDM2-associated ubiquitination. CaLa-induced Ca²⁺ influx increased the motility of colon cancer cells was mediated by calpain activity through FAK and pFAK protein destabilization. In conclusion, these results suggest that careful consideration may be given in deciding dietary Ca²⁺ supplementation to patient undergoing treatment for metastatic cancer.     

Microstructures in the Organ of Corti Help Outer Hair Cells Form Traveling Waves along the Cochlear Coil

According to the generally accepted theory of mammalian cochlear mechanics, the fluid in the cochlear scalae interacts with the elastic cochlear partition to generate transversely oscillating displacement waves that propagate along the cochlear coil. Using a computational model of cochlear segments, a different type of propagating wave is reported, an elastic propagating wave that is independent of the fluid-structure interaction. The characteristics of the propagating wave observed in the model, such as the wavelength, speed, and phase lag, are similar to those observed in the living cochlea. Three conditions are required for the existence of the elastic propagating wave in the cochlear partition without fluid-interaction: 1), the stiffness gradient of the cochlear partition; 2), the elastic longitudinal coupling; and 3), the Y-shaped structure in the organ of Corti formed by the outer hair cell, the Deiters cell, and the Deiters cell phalangeal process. The elastic propagating waves in the cochlear partition disappeared without the push-pull action provided by the outer hair cell and Deiters cell phalangeal process. The results suggest that the mechanical feedback of outer hair cells, facilitated by the organ of Corti microstructure, can control the tuning and amplification by modulating the cochlear traveling wave.     

Prevalence of Post-Stroke Cognitive Impairment in China: A Community-Based,Cross-Sectional Study

International hospital-based studies have indicated a high risk of cognitive impairment after stroke, evidence from community-based studies in China is scarce. To determine the prevalence of post-stroke cognitive impairment (PSCI) and its subtypes in stroke survivors residing in selected rural and urban Chinese communities, we conducted a community-based, cross-sectional study in 599 patients accounting for 48% of all stroke survivors registered in the 4 communities, who had suffered confirmed strokes and had undergone cognitive assessments via the Montreal Cognitive Assessment (MoCA), Mini-Mental State Examination (MMSE), and Hachinski Ischemia Scale (HIS). Detection of PSCI was based on scores in these neuropsychological scales. Factors potentially impacting on occurrence of PSCI were explored by comparing demographic characteristics, stroke features, and cardiovascular risk factors between patients with and without PSCI. The overall prevalence of PSCI was 80.97% (95%CI: 77.82%-84.11%), while that of non-dementia PSCI (PSCI-ND) and post-stroke vascular dementia (PSD) was 48.91% (95%CI: 44.91%-52.92%) and 32.05% (95%CI: 28.32%-35.79%), respectively. Prior stroke and complications during the acute phase were independent risk factors for PSCI. The risk of recurrent stroke survivors having PSCI was 2.7 times higher than for first-episode survivors, and it was 3 times higher for those with complications during the acute phase than for those without. The higher prevalence of PSCI in this study compared with previous Chinese studies was possibly due to the combined effects of including rural stroke survivors, a longer period from stroke onset, and different assessment methods. There is an urgent need to recognize and prevent PSCI in stroke patients, especially those with recurrent stroke and complications during the acute phase.     

Ontogeny of head and caudal fin shape of an apex marine predator: The tiger shark (Galeocerdo cuvier)

How morphology changes with size can have profound effects on the life history and ecology of an animal. For apex predators that can impact higher level ecosystem processes, such changes may have consequences for other species. Tiger sharks (Galeocerdo cuvier) are an apex predator in tropical seas, and, as adults, are highly migratory. However, little is known about ontogenetic changes in their body form, especially in relation to two aspects of shape that influence locomotion (caudal fin) and feeding (head shape). We captured digital images of the heads and caudal fins of live tiger sharks from Southern Florida and the Bahamas ranging in body size (hence age), and quantified shape of each using elliptical Fourier analysis. This revealed changes in the shape of the head and caudal fin of tiger sharks across ontogeny. Smaller juvenile tiger sharks show an asymmetrical tail with the dorsal (upper) lobe being substantially larger than the ventral (lower) lobe, and transition to more symmetrical tail in larger adults, although the upper lobe remains relatively larger in adults. The heads of juvenile tiger sharks are more conical, which transition to relatively broader heads over ontogeny. We interpret these changes as a result of two ecological transitions. First, adult tiger sharks can undertake extensive migrations and a more symmetrical tail could be more efficient for swimming longer distances, although we did not test this possibility. Second, adult tiger sharks expand their diet to consume larger and more diverse prey with age (turtles, mammals, and elasmobranchs), which requires substantially greater bite area and force to process. In contrast, juvenile tiger sharks consume smaller prey, such as fishes, crustaceans, and invertebrates. Our data reveal significant morphological shifts in an apex predator, which could have effects for other species that tiger sharks consume and interact with. J. Morphol. 277:556–564, 2016. © 2016 Wiley Periodicals, Inc.     

Rapid fractionation of bovine transferrin using immobilized gangliosides.

Bovine transferrin (BTF) was fractionated from bovine whey using ganglioside affinity chromatography. After loading the immobilized matrix with a 2% whey solution, the matrix was washed with sodium acetate buffer at pH 4 containing 1 M NaCl before elution of BTF with sodium phosphate buffers at pH 7. Concanavalin-A affinity and ion exchange chromatography were used for further purification. The ganglioside column showed a 74.2% BTF recovery from whey and BTF was enriched to 61% purity with ion exchange chromatography. Bovine transferrin was identified by SDS-PAGE and western analysis. The Concanavalin-A affinity and ion exchange chromatography steps enriched BTF in the samples and removed other whey proteins from ganglioside purified fractions. These results indicate that immobilized ganglioside can be used to fractionate BTF from bovine whey. Our novel ganglioside affinity chromatography is rapid and efficient for the fractionation of BTF from whey.     

Continuous culture of a recombinantEscherichia coli and plasmid maintenance for tryptophan production

Summary Production of tryptophan by a temperature sensitive recombinant microorganism (Escherichia coli W3110 trpLDtrpR ^ts tna ^– (pCRT185)) was investigated. In a single-stage continous culture, at an elevated temperature, 42°C (derepressed condition), tryptophan concentration increased in an early phase of the fermentation, and then gradually decreased with time. The reduction in the production rate was mostly due to the segregation of the plasmid and subsequent increase of plasmid-free cells. However, the plasmid could be maintained stable at 37°C, with repressed condition oftrp-operon, over 200 generations. A two-stage continuous culture system, i.e. cell growth was maintained in the first stage at 37°C and gene expression was induced in the second stage at 42°C, was therefore tested to improve the performance of the fermentation system. Operation of the two-stage system showed that the plasmid stability was significantly improved, and the specific rate of tryptophan production was maintained almost constant for more than 500 hours in the second stage.     

Cleavage of territrems by alkaline hydrogen peroxide: Isolation and characterization of the aromatic moiety of territrems

The chemical reaction of cleavaging territrem B to give 3,4,5-trimethoxy benzoic acid by alkaline hydrogen peroxide was investigated. The method was applied for confirmation of the chemical structure of the aromatic moiety of territrem A, A’, B, and B’. The physicochemical properties of the aromatic cleavage product of territrem Aindicated the structure as 3,4-methylendioxy, 5-methoxy benzoic acid (or 4-methoxy, 6-carboxy, 1, 3-benzodioxole). The experiment also gave the evidences that territrem A and A’, on the other hand territrem B and B’ have the identical aromatic moieties on their structures.     

On two tests of fit for HLA data with no double blanks.

Stevens suggests a test of fit, based on Bernstein's estimators, of the Hardy-Weinberg law for the ABO system. Nam and Gart extend this test to the generalized ABO-like system and apply it to HLA data. When the recessive gene is rare, Huether and Murphy recall Haldane's point that its Bernstein's estimator is negatively biased and go on to suggest novel corrected versions of it. With the identification of more HLA antigens, it is not uncommon to find, in certain populations, that the sample data contain no double blanks; that is, every individual reacts to at least one antigen for a given locus. Gart and Nam give a simple score test of a zero true recessive-gene frequency for such situations. Here we examine the extended test of Stevens as a test of this hypothesis. We find that it is fully efficient for two codominant alleles but that when the number exceeds two its efficiency may be 50% or lower or as high as 100%, depending on the number of alleles and the pattern of gene frequencies. The tests are applied to a set of HLA data.     

Urinary gonadotropin fragment (UGF) measurements in the diagnosis and management of ovarian cancer

UGF is a small peptide present in the urines and tissues of patients with gynecologic cancers. Published research (which, at present, mainly comes from our laboratory) on the general application of UGF as a tumor marker, and on its use in the diagnosis of ovarian cancer, is reviewed, and new studies on its use, alone and with CA125, in the management of patients with ovarian cancer, are presented. In 234 healthy women, 89 with benign disease, and 79 with ovarian cancer, UGF levels were above 3 fmol/ml (low cut-off) in 12 percent, 7 percent, and 82 percent, respectively, and above 8 fmol/ml (high cut-off) in 1.7 percent, less than 1.1 percent, and 59 percent, respectively. Similarly, 11 percent, 14 percent, and 70 percent, respectively, had CA125 levels above 35 U/ml (low cut-off), and less than 1.9 percent, 1.2 percent, and 49 percent had levels above a 200 U/ml (high cut-off). Ideally, the higher UGF and CA125 cut-offs should be used for diagnostic applications, like differentiation of a benign from a malignant pelvic mass (false-positive rate: UGF, less than 1.1 percent; CA125, 1.2 percent), but raising the cut-offs diminishes sensitivities for malignancy (UGF, 59 percent; CA125, 49 percent). The populations detected by the two markers only partially overlap, however, so that, together, UGF or CA125 can identify 75 percent of malignant pelvic masses. Levels of UGF (cut-off, greater than 3 fmol/ml) and CA125 (35 U/ml) were also monitored in 30 women undergoing therapy for ovarian cancer. Clinical observations were reflected at each clinic visit by UGF alone in 67 percent, by CA125 alone in 57 percent, and by UGF and CA125 together in 87 percent of cases. While separately UGF and CA125 levels predicted 71 percent and 57 percent, together they forecast 86 percent of recurrent cancers prior to clinical manifestations. UGF and CA125 should be used together in the detection and management of ovarian cancers.     

Citric acid production by Aspergillus niger immobilized on polyurethane foam

Summary Citric acid was produced using Aspergillus niger immobilized on polyurethane foam in a bubble column reactor. Most of the adsorbed cells remained on the support and, as a result, high oxygen tension was maintained during the reactor operation. However, uncontrolled growth of the pellets made continuous reactor operation difficult. The citric acid productivity obtained from 15 vol.% foam particles containing immobilized cells was 0.135 g/l per hour. This productivity of immobilized cells was almost the same as that of free cells. The oxygen level dropped to half saturation in 5 days in the immobilized cell culture in contrast to 2 days in the free cell culture.