An acoustic method for the analysis of bacterial cells

The application of a biological electroacoustic sensor based on a lateral electric-field-excited piezoelectric resonator for the study of bacterial cells that interact with specific bacteriophages, mini-antibodies, and polyclonal antibodies was successfully demonstrated. The determined lower limit of microbialcell detection was approximately of 10³ to 10⁴ cells/mL for the duration of the assay of 10 min. The possibility of bacterial-cell detection via interaction with specific agents in the presence of extraneous microbiota was shown. The method allowed us to determine the spectrum of lytic activity of bacteriophages and the sensitivity of microbial cells to bacteriophages. The results of the study showed that application of a sensor piezoelectric lateral-field resonator is a promising technique for the detection and identification of microbial cells and determination of their phage resistance in microbiology, medicine, and veterinary medicine. Furthermore, the results of the experiments made it possible to understand the mechanisms of the processes that occur in a suspension of bacterial cells in the presence of various biological agents. The method also may provide useful information regarding biophysical mechanisms of interactions that occur in microbial populations.     

A Longitudinal Study of Disability,Cognition and Gray Matter Atrophy in Early Multiple Sclerosis Patients According to Evidence of Disease Activity

New treatment options may make “no evidence of disease activity” (NEDA: no relapses or disability progression and no new/enlarging MRI lesions, as opposed to “evidence of disease activity” (EDA) with at least one of the former), an achievable goal in relapsing-remitting multiple sclerosis (RRMS). The objective of the present study was to determine whether early RRMS patients with EDA at one-year follow-up had different disability, cognition, treatment and gray matter (GM) atrophy rates from NEDA patients and healthy controls (HC). RRMS patients (mean age 34 years, mean disease duration 2.2 years) were examined at baseline and one-year follow-up with neurological (n = 72), neuropsychological (n = 56) and structural MRI (n = 57) examinations. Matched HC (n = 61) were retested after three years. EDA was found in 46% of RRMS patients at follow-up. EDA patients used more first line and less second line disease modifying treatment than NEDA (p = 0.004). While the patients groups had similar disability levels at baseline, they differed in disability at follow-up (p = 0.010); EDA patients progressed (EDSS: 1.8–2.2, p = 0.010), while NEDA patients improved (EDSS: 2.0–1.7, p<0.001). Cognitive function was stable in both patient groups. Subcortical GM atrophy rates were higher in EDA patients than HC (p<0.001). These results support the relevance of NEDA as outcome in RRMS and indicate that pathological neurodegeneration in RRMS mainly occur in patients with evidence of disease activity.     

The botany,uses and production ofWasabia japonica (Miq.) (Cruciferae) Matsum

Wasabi (Wasabia japonica) is a unique native plant and a traditional condiment crop of Japan. It is used in traditional Japanese raw fish and noodle dishes and in several modern foods for its hot taste and tangy flavor. Japanese farmers grow the crop in wet upland orchard soils for leaves, petioles and small enlarged stems, and in flooded gravel and sand fields along streams or near springs to produce whole plants and large succulent green enlarged stems. Recent studies in Japan have demonstrated numerous enzymatic and biocidal properties of the plant. This review of Japanese and other literature details the history, uses, botany, cultivars, ecological requirements, production techniques, insect pests and diseases of wasabi.     

High intensity physical exercise induced effects on plasma levels of copper and zinc

Physical exercise leads to many metabolic, cardiovascular, and muscular changes in the body. The trace elements (TE) zinc and copper are directly involved, as enzymatic cofactors, in many of these processes, especially those related to nutrients metabolism, oxygen transport, and formation of usable energy. The effects of high-intensity physical exercise on plasma levels of CU²⁺ and Zn²⁺ in 19 subjects are investigated (9 males and 10 females). Plasma copper concentration decreases, and plasma zinc concentration increases, after exercise, in both sexes. After 30 min recovery, both TE concentration values shifts-toward rest values in both sexes. These results only partially agree with literature data, probably because we used the treadmill exercise, which makes many muscles work, whereas other authors made their subjects perform a cycloergometer exercise. Physical exercise causes a marked redistribution of TE (copper and zinc) between body stores, bloodstream, and tissues. The condition of high metabolism may lead to a deficiency of TE, requiring supplementation in order to maintain high level performance.     

Interleukin-6 and alpha-2-macroglobulin indicate an acute-phase state in Alzheimer's disease cortices.

Recent studies indicated that the formation of a major constituent of Alzheimer's disease (AD) senile plaques, called beta A4-peptide, does not result from normal processing of its precursor, amyloid precursor protein (APP). Since proteolytic cleavage of APP inside its beta A4 sequence was found to be part of APP processing the formation of the beta A4-peptide seems to be prevented under normal conditions. We considered whether in AD one of the endogenous proteinase inhibitors might interfere with APP processing. After we had recently found that cultured human neuronal cells synthesize the most potent of the known human proteinase inhibitors, alpha-2-macroglobulin (alpha 2M), upon stimulation with the inflammatory mediator interleukin-6 (IL-6) we now investigated whether alpha 2M and IL-6 could be detected in AD brains. Here we report that AD cortical senile plaques display strong alpha 2M and IL-6 immunoreactivity while no such immunoreactivity was found in age-matched control brains. Strong perinuclear alpha 2M immunoreactivity in hippocampal CA1 neurons of Alzheimer's disease brains indicates that neuronal cells are the site of alpha 2M synthesis in AD brains. We did not detect elevated IL-6 or alpha 2M levels in the cerebrospinal fluid of AD patients. Our data indicate that a sequence of immunological events which seem to be restricted to the local cortical environment is part of AD pathology.     

Analysis of the pivotal residues of the immunodominant and highly uveitogenic determinant of interphotoreceptor retinoid-binding protein.

Interphotoreceptor retinoid-binding protein (IRBP), a retinal-specific Ag, induces experimental autoimmune uveitis in a variety of animals. We have previously shown that sequence 1169-1191 of bovine IRBP is the immunodominant epitope of this protein in Lewis rats and is highly immunogenic and uveitogenic in these rats. The active site of peptide 1169-1191 was determined by testing its truncated forms. The shortest peptide to be immunologically active was found to be 1182-1190 (WEGVGVVPD). To determine the role of individual residues of this sequence, we have tested the immunologic activities of nine analogs of peptide 1181-1191, in which each of residues 1182-1190 was substituted with alanine (A). The tested activities included the capacity to induce experimental autoimmune uveitis and cellular responses in immunized rats, as well as the capability to stimulate lymphocytes sensitized against IRBP or the parent peptide 1181-1191. Analogs that did not stimulate these lymphocytes were also tested for their capacity to competitively inhibit the proliferative response to 1181-1191. Analogs A(1184), A(1186), and A(1187) resembled 1181-1191 in their activities, whereas the other analogs exhibited remarkably reduced activities, with several patterns being noticed. Analog A(1182) was inactive in all tests. Analog A(1190) was very weakly uveitogenic and non-immunogenic, but it stimulated lymphocytes sensitized against IRBP or 1181-1191 when added at exceedingly high concentrations. Analogs A(1183) and A(1185) resembled A(1190) in being weakly uveitogenic and A(1185) was also found to be poorly immunogenic. In addition, relatively high concentrations of A(1183) and A(1185) were needed to stimulate lymphocytes sensitized against IRBP or 1181-1191. However, a different pattern of activities was exhibited by analogs A(1188) and A(1189). These peptides were uveitogenic and immunogenic, but failed to stimulate lymphocytes sensitized to IRBP or 1181-1191. Furthermore, A(1188) and A(1189), but not A(1182), also inhibited the response to 1181-1191 of a cell line specific toward this parent peptide. The data are interpreted to show that residues 1188 and 1189 are involved in the interaction of the peptide with the TCR, whereas residues 1182 and 1190 and, perhaps, 1183 and 1185, are pivotal for the binding of peptide 1181-1190 to the MHC molecules on APC.     

Improvement of a Vero cell assay to determine diphtheria antitoxin content in sera

Diphtheria antitoxin content in sera were determined automatically in Vero cell assay by spectrophotometric determination of the equivalence point between toxin and antitoxin followed by computer analysis of absorption values. The method was more accurate than visual reading and made handling of many samples easy.     

Platelet-activating factor induces tyrosine phosphorylation in human neutrophils

The addition of platelet-activating factor (PAF) to human neutrophils increases the levels of the tyrosine phosphorylation in several proteins. These proteins have molecular weights of 41 (pp41), 54 (pp54), 66 (pp66), 104 (pp104), and 116 (pp116) kDa. The effect of PAF was dose-dependent and could be seen at concentrations as low as 1 nM. The nonmetabolizable bioactive PAF analog, C-PAF, caused an increase in the level of phosphorylation of the same proteins in a time- and dose-dependent manner. On the contrary, lyso-PAF, enantio-PAF, and L-beta,gamma-dihexadecyl-alpha-lecithin failed to stimulate the phosphorylation of any of the aforementioned proteins. The response to PAF was prevented by the PAF antagonist BN-52021. The PAF-induced increases in tyrosine phosphorylation in pp66, pp116, and pp104 were selectively inhibited by pertussis toxin. In contrast, the level of pp41 phosphorylation remained unchanged after the pertussis toxin treatment. The calcium chelator EGTA significantly inhibited the PAF-produced phosphorylation of the pp41 protein. The intracellular calcium chelator 1,2-bis-(O-aminophenoxil)ethane-N,N,N',N'-tetraacetic acid (BAPTA) potentiated the PAF-enhanced levels of tyrosine phosphorylation on the pp41 protein. On the other hand, the PAF-induced phosphorylations of pp66, pp104, and pp116 were inhibited in BAPTA-treated cells. The calcium ionophore A23187 selectively potentiated the phosphorylation of the pp41 protein and reduced the phosphorylation in the pp54 protein. This phosphorylation was dependent on the extracellular calcium and was inhibited in toxin-treated cells. The results suggest that PAF is able to affect either directly or indirectly tyrosine kinase and/or phosphotyrosine phosphatase activities. The phosphorylation of the high and low molecular weight proteins are mediated by two different sets of kinases and/or phosphatases.