Electrical responses of the superior olivary complex in Vespertilionidae and Rhinolophidae to ultrasonic stimuli with different fill frequency

Global and single unit responses of the superior olivary complex were investigated during ultrasonic stimulation at different frequencies in two species of bats from the Vespertilionidae, which emit frequency-modulated signals and the Rhinolophidae, which utilize almost monochromatic (80 ± 1 kHz) echolocation cries. Maximal sensitivity to ultrasound in the Vespertilionidae was found at frequencies of 10–40 kHz, and in the Rhinolophidae also within the range 10–40 kHz but with a second increase in sensitivity in the region 82–86 kHz. Sharply tuned neurons were more numerous in the Rhinolophidae than in the Vespertilionidae. Neurons whose response in the echolocation frequency band changed in character depending on the fill frequency of the stimulus were found in Rhinolophidae: a phasic discharge occurs over a wide range of frequencies and a tonic discharge at the characteristic frequency; the latter was also observed over a limited range of intensities.A. A. Zhdanov Leningrad State University. Translated from Neirofiziologiya, Vol. 5, No. 1, pp. 33–39, January–February, 1973.     

Identification of endogenous control genes for normalisation of real-time quantitative PCR data in colorectal cancer

Background  

Gene expression analysis has many applications in cancer diagnosis, prognosis and therapeutic care. Relative quantification is the most widely adopted approach whereby quantification of gene expression is normalised relative to an endogenously expressed control (EC) gene. Central to the reliable determination of gene expression is the choice of control gene. The purpose of this study was to evaluate a panel of candidate EC genes from which to identify the most stably expressed gene(s) to normalise RQ-PCR data derived from primary colorectal cancer tissue.     

The effect of low-intensity red and infrared laser radiation on the rat arterial and deoxygenated blood

In vitro experiments the effect of low-intensity red or near-infrared laser irradiation on the blood samples (1.5 ml from abdominal aorta of Wistar rats) were studied. The diode laser light (lambda = 650 nm or 808 nm, power density 15.6 mW/cm2, duration 15 min) were used. In some experiments the deoxygenated blood as object for comparison with arterial blood was chosen. Under red laser irradiation we observed a significant increase of average volume of erythrocytes as well as mean amount of free (disaggregated) leukocytes especially in case of the deoxygenated blood. At the same time the concentration of Ca2+ and Na+ were decreased. The effects of infrared laser irradiation on indices mentioned above were not significant. We believe that red low-intensity laser irradiation on the blood is an important factor for theological properties in the field of microcirculation.     

Chitin hydrolysate stimulates VEGF-C synthesis by MDA-MB-231 breast cancer cells

Up-regulation of VEGF-C (vascular endothelial growth factor C), a most potent lymphangiogenic factor, is associated with inflammation and cancer metastasis. Identification of stimuli contributing to these processes is a challenging task. I demonstrate in this paper that chitin hydrolysate served as a strong inducer of VEGF-C synthesis by human breast cancer MDA-MB-231 cells, increasing the secretion of VEGF-C to the cell culture medium as much as by 10-fold in comparison with the basal production. A moderate increase of VEGF-C secretion was also observed in the presence of hypertonic doses of NaCl, which mimicked the matrix of chitin hydrolysate stock solution, and in the presence of chitin-binding lectin, WGA (wheat germ agglutinin). WGA, but not chitin hydrolysate, significantly affected the morphology of cells, which become smaller and rounded as assessed by viewing the actin cytoskeleton. Moreover, chitin hydrolysate inhibited the lectin effect on the cytoskeleton and sustained the overproduction of VEGF-C indicating that WGA-independent receptors were responsible for chitin-mediated stimulation of VEGF-C synthesis. These results suggest a novel function of chitin-derived oligosaccharides as VEGF-C stimuli.     

Novel technique for biliary reconstruction using an isolated gastric tube with a vascularized pedicle: a live animal experimental study and the first clinical case

Background

Biliary tract reconstruction continues to be a challenging surgical problem. Multiple experimental attempts have been reported to reconstruct biliary defects with different materials and variable outcome. Our aim was to evaluate a new method for biliary reconstruction using an isolated pedicled gastric tube in a live animal trial and also to present the first clinical case.

Methods

Seven mongrel dogs underwent biliary reconstruction using gastric tube harvested, completely separated from the greater curvature, and based on a vascularized pedicle with the right gastroepiploic vessels. The tube was interposed between the common bile duct (CBD) and the duodenum. Postoperative mortality, morbidity, liver functions, gross and microscopic histological picture were assessed. The first clinical case was also presented where, in a patient with post-cholecystectomy biliary injury, an isolated pedicled gastric tube was interposed between the proximal and distal ends of the CBD.

Results

One dog did not recover from anesthesia and another one died postoperatively from septic peritonitis. Five dogs survived the procedure and showed uneventful course and no cholestasis. The mean anastomotic circumference was 4.8 mm (range 4-6) for CBD anastomosis and 6.2 mm (range 5-7) for duodenal anastomosis. Histologically, anastomotic sites showed good evidence of healing. In the first clinical case, the patient showed clinical and biochemical improvement. Endoscopic retrograde cholangiography was feasible and assured patent biliary anastomoses.

Conclusion

In mongrel dogs, biliary reconstruction using pedicled gastric tube interposition between CBD and duodenum is feasible with satisfactory clinical results, anastomotic circumference and histological evidence of healing. The technique is also feasible in human and seems to be promising.     

Studies of the transmissibility of the agent of bovine spongiform encephalopathy to the domestic chicken

Background

Escherichia coli O157:H7 is the most common serovar of enterohemorrhagic E. coli associated with serious human disease outbreaks. Cattle are the main reservoir with E. coli O157:H7 inducing hemorrhagic enteritis in persistent shedding beef cattle, however little is known about how this pathogen affects cattle health. Jejunal Hemorrhage Syndrome (JHS) has unclear etiology but the pathology is similar to that described for E. coli O157:H7 challenged beef cattle suggestive that E. coli O157:H7 could be involved. There are no effective treatments for JHS however new approaches to managing pathogen issues in livestock using prebiotics and probiotics are gaining support. The first objective of the current study was to characterize pathogen colonization in hemorrhaged jejunum of dairy cattle during natural JHS outbreaks. The second objective was to confirm the association of mycotoxigenic fungi in feeds with the development of JHS and also to identify the presence of potential mycotoxins. The third objective was to determine the impact of a prebiotic, Celmanax?, or probiotic, Dairyman's Choice? paste, on the cytotoxicity associated with feed extracts in vitro. The fourth objective was to determine the impact of a prebiotic or a probiotic on E. coli O157:H7 colonization of mucosal explants and a bovine colonic cell line in vitro. The final objective was to determine if prebiotic and probiotic feed additives could modify the symptoms that preceded JHS losses and the development of new JHS cases.

Findings

Dairy cattle developed JHS after consuming feed containing several types of mycotoxigenic fungi including Fusarium culmorum, F. poae, F. verticillioides, F. sporotrichioides, Aspergillus flavus, Penicillium roqueforti, P. crustosum, P. paneum and P. citrinum. Mixtures of Shiga toxin - producing Escherichia coli (STEC) colonized the mucosa in the hemorrhaged tissues of the cattle and no other pathogen was identified. The STECs expressed Stx1 and Stx2, but more significantly, Stxs were also present in the blood clot blocking the jejunum. Mycotoxin analysis of the corn crop confirmed the presence of fumonisin, NIV, ZEAR, DON, 15-ADON, 3-ADON, NEO, DAS, HT-2 and T-2. Feed extracts were toxic to enterocytes and 0.1% Celmanax? removed the cytotoxicity in vitro. There was no effect of Dairyman's Choice? paste on feed-extract activity in vitro. Fumonisin, T-2, ZEAR and DON were toxic to bovine cells and 0.1% Celmanax? removed the cytotoxicity in vitro. Celmanax? also directly decreased E. coli O157:H7 colonization of mucosal explants and a colonic cell line in a dose-dependent manner. There was no effect of Dairyman's Choice? paste on E. coli O157:H7 colonization in vitro. The inclusion of the prebiotic and probiotic in the feed was associated with a decline in disease.

Conclusion

The current study confirmed an association between mycotoxigenic fungi in the feed and the development of JHS in cattle. This association was further expanded to include mycotoxins in the feed and mixtures of STECs colonizing the severely hemorrhaged tissues. Future studies should examine the extent of involvement of the different STEC in the infection process. The prebiotic, Celmanax?, acted as an anti-adhesive for STEC colonization and a mycotoxin binder in vitro. Future studies should determine the extent of involvement of the prebiotic in altering disease.     

Co-expression of α9β1 integrin and VEGF-D confers lymphatic metastatic ability to a human breast cancer cell line MDA-MB-468LN

Introduction and Objectives

Lymphatic metastasis is a common occurrence in human breast cancer, mechanisms remaining poorly understood. MDA-MB-468LN (468LN), a variant of the MDA-MB-468GFP (468GFP) human breast cancer cell line, produces extensive lymphatic metastasis in nude mice. 468LN cells differentially express α9β1 integrin, a receptor for lymphangiogenic factors VEGF-C/-D. We explored whether (1) differential production of VEGF-C/-D by 468LN cells provides an autocrine stimulus for cellular motility by interacting with α9β1 and a paracrine stimulus for lymphangiogenesis in vitro as measured with capillary-like tube formation by human lymphatic endothelial cells (HMVEC-dLy); (2) differential expression of α9 also promotes cellular motility/invasiveness by interacting with macrophage derived factors; (3) stable knock-down of VEGF-D or α9 in 468LN cells abrogates lymphangiogenesis and lymphatic metastasis in vivo in nude mice.

Results

A comparison of expression of cyclo-oxygenase (COX)-2 (a VEGF-C/-D inducer), VEGF-C/-D and their receptors revealed little COX-2 expression by either cells. However, 468LN cells showed differential VEGF-D and α9β1 expression, VEGF-D secretion, proliferative, migratory/invasive capacities, latter functions being stimulated further with VEGF-D. The requirement of α9β1 for native and VEGF-D-stimulated proliferation, migration and Erk activation was demonstrated by treating with α9β1 blocking antibody or knock-down of α9. An autocrine role of VEGF-D in migration was shown by its impairment by silencing VEGF-D and restoration with VEGF-D. 468LN cells and their soluble products stimulated tube formation, migration/invasiveness of HMVEC-dLy cell in a VEGF-D dependent manner as indicated by the loss of stimulation by silencing VEGF-D in 468LN cells. Furthermore, 468LN cells showed α9-dependent stimulation of migration/invasiveness by macrophage products. Finally, capacity for intra-tumoral lymphangiogenesis and lymphatic metastasis in nude mice was completely abrogated by stable knock-down of either VEGF-D or α9 in 468LN cells.

Conclusion

Differential capacity for VEGF-D production and α9β1 integrin expression by 468LN cells jointly contributed to their lymphatic metastatic phenotype.     

Photoluminescent biocompatible silicon nanoparticles for cancer theranostic applications

Silicon nanoparticles (SiNPs) obtained by mechanical grinding of porous silicon have been used for visualization of living cells in vitro. It was found that SiNPs could penetrate into the cells without any cytotoxic effect up to the concentration of 100 μg/ml. The cell cytoplasm was observed to be filled by SiNPs, which exhibited bright photoluminescence at 1.6 eV. SiNPs could also act as photosensitizers of the singlet oxygen generation, which could be used in the photodynamic therapy of cancer. These properties of SiNPs are discussed in view of possible applications in theranostics (both in therapy and in diagnostics). (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Various indicators of humoral immunity in patients with hematopoietic hypoplasia after bone marrow transplantation]

The authors examined 65 patients with hypoplasia of the hemopoiesis following bone marrow transplantation. To patients of the 1st group the bone marrow was chosen by erythrocytic antigens only, and to patients of the 2nd group both by erythrocytic and by leukocytic antigens. The data obtained pointed to the reduction of isoimmunization to the antigens of leukocytes and platelets in the patients with hypoplasia of the hemopoiesis following transplantation of the histocompatible bone marrow, in comparison with the patients in whom the bone marrow was chosen only by erythrocytic antigens alone.