Variability of cortical evoked potentials to tooth pulp stimulation in unrestrained rats

In unrestrained adult rats evoked potentials were recorded by implanted electrodes in the somatosensory cortex in response to electrical stimulation of the pulp of an upper incisor. The spontaneous EEG, motor activity of the animal, and its respiratory movements were recorded simultaneously. Significant differences were observed in the configuration of the potentials and mean amplitude of the primary complex (P₁+N₁) during states of slow sleep, drowsiness, relaxed wakefulness, grooming, and investigative behavior; the amplitude of the primary complex during marked motor activity was reduced by more than an order of magnitude compared with that observed in a state of motor rest.In a state of relaxed wakefulness negative correlation was recorded between the amplitude of evoked potentials and momentary values of the respiration rate, weaker during periods of intensive motor activity. Meanwhile no direct parallel was observed between changes in potentials and respiration rate over the whole range of behavioral states studied: Depression of potentials was maximal during grooming whereas the respiration rate was maximal during investigative behavior.Paul Flechsig Institute for Brain Research, Karl Marx University, Leipzig, East Germany. Translated from Neirofiziologiya, Vol. 17, No. 1, pp. 27–35, January–February, 1985.     

Gastric inflammatory markers and interleukins in patients with functional dyspepsia, with and without Helicobacter pylori infection

Helicobacter pylori is the most important cause of gastritis, peptic ulcers and the development of gastric cancer. The chronic active inflammation is dominated by neutrophils, macrophages, lymphocytes and plasma cells. Several interleukins (IL-8, IL-10 and IFN-gamma) are involved in the inflammatory process in the gastric mucosa. The aim of this study was to investigate the gastric inflammation in patients with functional dyspepsia. Fifty-three consecutive patients were included and antral biopsies were obtained for histology, culture and immunohistochemistry. The sections were examined for the interleukins IL-4, IL-6, IL-8, IL-10 and IFN-gamma as well as for the cell markers CD4, CD8, CD14, Cd19, CD25 and CD30. Only CD4 and CD19 were significantly increased in patients with increased gastric inflammation and increased density of H. pylori. However, several of the examined markers (IFN-gamma, IL-8, IL-10 and CD14) showed a non-significant trend to be increased in patients with extensive gastric inflammation and high density of H. pylori. Therefore, an arbitrary index (IM11) for all the 11 immunological markers was made as an average value for each of the four morphological groups. For the four morphologically different groups of patients the values were 0.49, 0.77, 0.86 and 1.25, respectively. Significant increases in the index from none to moderate antral inflammation as well as the density of H. pylori were found (p<0.001). By using an index of inflammatory markers trends can be summarized and thereby significant which may be of importance when gastric inflammation is investigated in children and patients with functional dyspepsia.     

Characterization of the PCR inhibitory effect of bile to optimize real-time PCR detection of Helicobacter species

The inhibitory effect of human and porcine bile samples to detect Helicobacter DNA was studied by adding different concentrations of bile samples to PCR mixtures of six thermostable DNA polymerases containing cagA specific primers and Helicobacter pylori DNA. PCR products were amplified by using the Rotorgene system and SYBR Green I. Among the six DNA polymerases tested, rTth had the lowest sensitivity to bile inhibitors, whereas Taq and Tfl had the highest sensitivity. Bile proteins did not inhibit AmpliTaq DNA polymerase, whereas the fraction containing mainly bile acids and their salts inhibited the amplification capacity of AmpliTaq. Heating human bile at 98 degrees C and adding casein and formamide to the reaction mixture reduced the PCR inhibitory effect of bile. Therefore, a pre-PCR treatment based on dilution and heating of bile, adding casein and formamide to the reaction mixture of rTth DNA polymerase was found efficient to amplify DNA directly in bile.     

Factors related to health-related quality of life in ankylosing spondylitis,overall and stratified by sex

Background

Ankylosing spondylitis (AS) begins early in life and often leads to reduced physical function, but less is known about the impacts it has on health-related quality of life (HRQoL). The aims of this study were to assess HRQoL using the Short Form-36 (SF-36) in a cohort of patients with AS compared with controls and to examine associations between SF-36 scores and spinal radiographic changes, physical function, disease activity and demographic data overall and stratified by sex.

Methods

A cohort of patients with AS from Western Sweden were assessed using the Modified Stoke Ankylosing Spondylitis Spine Score (mSASSS) with spinal radiographs, clinical examination and questionnaires, including the Bath Ankylosing Spondylitis Metrology Index, Bath Ankylosing Spondylitis Functional Index (BASFI), Ankylosing Spondylitis Disease Activity Score-C-reactive protein (ASDAS-CRP), Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Patient Global (BASG) and SF-36. Each patient’s SF-36 results were compared with those of five age-matched and sex-matched persons (n?=?1055) from the SF-36 Swedish normative population database. Associations between SF-36 physical component summary (PCS) and mental component summary (MCS) scores and disease-related and demographic factors were investigated using univariate and multivariable ogistic regression analyses with PCS and MCS below/above their respective median values as dependent variables.

Results

A total of 210 patients, age (median, IQR) 49.0 (21.2) years, symptom duration 24.0 (21.0) years, men 57.6% and HLAB27 87.1% were included. Patients with AS scored significantly lower (p?<?0.001) compared to controls in all SF-36 domains and component summaries; PCS 42.4 (14.5) in AS versus 52.4 (11.8) in controls and MCS 47.9 (20.0) in AS versus 54.1 (10.1) in controls. Both men and women scored significantly lower in PCS compared with MCS. Multivariable logistic regression analyses revealed that living without a partner (OR 2.38, 95% CI 1.00–5.67), long symptom duration (year in decade OR 1.66, 95% CI 1.16–2.37), higher BASFI (OR 1.98, 95% CI 1.46–2.70) and ASDAS ≥?2.1 (OR 3.32, 95% CI 1.45–7.62) were associated with worse PCS, while living without a partner (OR 3.04, 95% CI 1.34–6.91), fatigue (visual analogue scale for global fatigue greater than the median (OR 6.36, 95% CI 3.06–13.19) and ASDAS ≥?2.1 (OR 2.97, 95% CI 1.41–6.25) with worse MCS. Some differences between sexes were observed in the results.

Conclusions

The patients with AS had significantly lower HRQoL compared with controls. PCS was more affected compared to MCS in both sexes. Both disease-related and demographic factors were associated with HRQoL, partly overlapping for PCS and MCS. Factors associated with HRQoL showed some differences between sexes. By modifying factors, such as ASDAS-CRP and fatigue, HRQoL may potentially be improved.

Trial registration

ClinicalTrials.gov, NCT00858819. Registered on 9 March 2009. Last updated on 28 May 2015.

     

Formation of Bacteriolytic Enzymes in Batch and Continuous Culture of Staphylococcus aureus

The formation of bacteriolytic enzymes of Staphylococcus aureus, with special reference to strain M18, was investigated under a variety of conditions. The bacteriolytic activity was tested by using whole cells of Micrococcus lysodeikticus as a substrate. Complex media were required for production, and a Casein Hydrolysate-Yeast Extract medium (CCY(I)) was superior to Brain Heart Infusion and Trypticase Soy Broth. The optimal pH level for production was 7.0. Effective oxygenation and exchange of the beta-glycerophosphate of the CCY(I) medium for glucose increased the rates of growth and autolysis and the rate of appearance of extracellular bacteriolytic enzymes. However, the extracellular lytic activity decreased more rapidly at the end of the growth period than under the standard culture conditions. The appearance of inhibitor(s), probably derived from autolysis, might be responsible for this rapid decrease. The highest yields were obtained in a continuous process in which the activity was almost twice that of batch cultures grown under the same conditions. The bacteriolytic activity produced in continuous culture had a considerably increased stability in the purification process. The advantage of producing unstable bacterial proteins in continuous culture under controlled growth conditions is discussed.     

High-affinity binding of laminin by Helicobacter pylori: Evidence for a lectin-like interaction

Abstract Laminin, the major glycoprotein of basement membranes, was shown to be bound by the human gastric pathogen Helicobacter pylori . Binding of ¹²⁵I-laminin by strain 17874 was time-dependent, specific and saturable. Scatchard analysis of specific binding indicated about 2000 binding sites per cell with a dissociation constant of 8.5 pM. Treatment of the cells by heat (80°) and with proteolytic enzymes drastically reduced laminin binding, suggesting that the laminin receptors are surface proteins. Some highly glycosylated glycoproteins inhibited laminin binding by 50%. Furthermore, N -acetylneuraminyllactose decreased laminin binding by 70% and neuraminidase treatment of laminin by 50%, while a recombinant B1 chain of laminin, containing high-mannose type oligosaccharides, inhibited binding by only 25%. This suggests that terminal sialic acids on laminin compete for a specific sugar binding protein(s) on H. pylori cells.