A renally active substance from heart muscle and from blood

1. A steroid-like compound has been isolated from cat heart muscle by thin-layer chromatography.2. This compound has been characterized by measurement of its R(F) values in two solvent systems.3. No similar substance could be detected in the 1 hr venous outputs of cat adrenals.4. It could not be detected in heart-lung circuit blood when the heart had been perfusing for 1(1/4)-1(1/2) hr at constant venous input and peripheral resistance. The compound was however extractable from the circuit blood 10-15 min after reduction in venous input.5. The actions of this compound on the isolated kidney resemble those of aldosterone but are of much shorter latency.6. The heart substance differs from aldosterone in R(F) values and has more than 10 times the renal activity of aldosterone when the two substances are equated (visually) for ability to reduce blue tetrazolium.     

Oxatomide inhibits the release of chemical mediators from human lung tissues and from granulocytes

The effects of oxatomide on the release of histamine and leukotriene C4 (LTC4) from human lung fragments and granulocytes were examined and the findings compared with the effects of the antiallergic drugs ketotifen, azelastine and tranilast. Oxatomide inhibited the release of both histamine and LTC4 from human lung fragments in cases of passive sensitization with human IgE myeloma serum upon anti-epsilon stimulation. IC50 values for the release of LTC4 from human lung fragments were as follows: oxatomide, 2.35 x 10(-5) M; azelastine, 27.2 x 10(-5) M; ketotifen, 52.1 x 10(-5) M; tranilast, 62.9 x 10(-5) M. Oxatomide also inhibited the release of both histamine and LTC4 from human mixed leukocytes stimulated by the calcium ionophore A23187. IC50 values for the release of LTC4 from human mixed leukocytes were as follows: oxatomide, 1.67 x 10(-5) M; azelastine, 3.65 x 10(-5) M; ketotifen, 12.2 x 10(-5) M; tranilast, 15.1 x 10(-5) M. The effects of oxatomide on the release of LTC4 from purified human neutrophils and eosinophils were also given attention. Oxatomide inhibited the release of LTC4 from eosinophils more effectively than from neutrophils and mixed leukocytes. As there is evidence that eosinophils play an important role in the development of late asthmatic responses and/or in the aggravation of asthma, oxatomide is expected to be an effective treatment for such conditions.     

Interaction of streptolysin O from Streptococcus pyogenes and theta-toxin from Clostridium perfringens with human fibroblasts

The membrane-damaging properties on human diploid embryonic lung fibroblasts of streptolysin O (from Streptococcus pyogenes) and theta-toxin (from Clostridium perfringens) were compared. The results are consistent with the suggested mechanism for hemolysis by streptolysin O involving one fixation site and one lytic site of this cytolysin. However, the membrane-damaging activity of the two toxins differed with respect to (i) relative cytolytic activity on human diploid lung fibroblasts compared with that on sheep erythrocytes, (ii) binding to the fibroblast membrane, (iii) activity at 0 degrees C, (iv) membrane repair after more than 30 min, and (v) effect on influx of amino acids. It is concluded that the mechanism of membrane damage caused by theta-toxin differs from that of cytoplasmic membrane. These results question the current concept that all thiol-activated, cholesterol-inactivated bacterial toxins are similar both structurally and functionally.     

Chloro-ionenes from dichlorides and tertiary diamines

Five new ionenes were synthesized from tertiary diamines and dihalides. For comparison, four bromo-ionenes were also prepared. Due to a lower C-Br bond energy the bromo-ionenes can be prepared from alkylene dibromides and tertiary diamines, whereas in case of chloroionenes the presence of electronegative atoms or groups of atoms in the dichlorides proved to be the condition to ensure reaction under moderate conditions. The highest initial reaction rates and lowest energies of activation (27,2–35,5 kJ/mol) were observed in runs with 1,3-dichloro-2-propanon ( 1 ). Similarly, bis(2-chloroethyl) ether ( 2a ) proved to be a convenient dihalide for the formation of chloro-ionenes, displaying reactivities comparable with those of 1,6-dibromohexane. All reaction orders referring to the preparation of bromo-ionenes investigated, were found to be about 2, whereas the formation of chloro-ionenes is first order. In case of bromoionenes the energies of activation were higher (66,7–79,8 kJ/mol) than in the case of chloroiones (27,2–51,8 kJ/mol). The structure of tertiary diamines plays an important role as far as their basicity is concerned, influenced by resonance conjugation, which is the case with Michler's ketone ( 5 ) as well as with tetramethylurea ( 6 ). The ionenes resulting from the dihalides and tertiary amines proved to be oligomers.     

Dust from carpeted and smooth floors

Dust samples were collected twice from smooth and carpeted floors in 10 Norwegian schools. The content of antigens and allergens of alder (Alnus incana), birch (Betula verrucosa), timothy (Phleum pratense), cat and dog dander, house dust mite (Dermatophagoides farinae), mould (Cladosporium herbarum), hen egg white and codfish (DIII) were investigated by crossed immunoelectrophoresis (CIE), crossed radio immunoelectrophoresis (CRIE), radio allergosorbent test (RAST) inhibition and quantitative precipitation inhibition analysis by laser nephelometry. Antigens and allergens of cat and dog dander and hen egg white were most prevalent in the dust samples investigated. With the exception of hen egg white and codfish allergens, no statistically significant differences in mean allergen content were shown in identical quantities of freeze-dried dust extracts from carpeted and smooth floors. RAST-inhibition analyses of identical amounts of dust from either floors showed higher content of allergens of cat, dog, hen egg white, codfish, mould and timothy pollen in classrooms with carpets.     

Immunorelatedness of Oligopeptidases from Lactobacillus and Lactococcus and Proline Iminopeptidase from Propionibacterium using Double Immunodiffusion Assay

Double immunodiffusion assay showed that species of lactobacilli produce immunologically unrelated oligopeptidases. Polyclonal antibodies (PAbs) specific for intracellular 70 kDa oligopeptidase type PepO from Lactobacillus curvatus reacted with intracellular protein(s) of cell-free extract (CFE) from Lb. paracasei and Lb. casei but not with intracellular proteins of Lb. plantarum , Lb. pseudoplantarum or Lb. helveticus . PAbs specific for 70 kDa oligopeptidase from Lactococcus lactis did not react with proteins in CFE from lactobacilli but at similar PepO activity reacted, with different affinity, with proteins in CFE of various lactococcal cultures. Antibodies specific for intracellular proline iminopeptidase from Propionibacterium freudenreichii reacted with proteins in the CFE from cultures of other dairy propionibacteria only.     

Mesodermal and Hematopoietic Differentiation from ES and iPS Cells

Embryonic stem (ES) and induced pluripotent stem (iPS) cells can differentiate into any type of tissue when grown in a suitable culture environment and are considered valuable tools for regenerative medicine. In the field of hematology, generation of hematopoietic stem cells (HSCs) and mature hematopoietic cells (HCs) from ES and iPS cells through mesodermal cells, the ancestors of HCs, can facilitate transplantation and transfusion therapy. Several studies report generation of functional HCs from both mouse and human ES and iPS cells. This approach will likely be applied to individual patient-derived iPS cells for regenerative medicine approaches and drug screening in the future. Here, we summarize current studies of HC-generation from ES and iPS cells.     

Qualitative and quantitative molecular detection of enteroviruses in water from bathing areas and from a sewage treatment plant

Pathogenic enteric viruses can be introduced into the environment as a result of human activities. Enteroviruses are regularly detected in environmental waters or shellfish and can provoke potentially serious diseases. Some authors believe that enteroviruses could represent an interesting indicator of viral contamination in the environment. Since molecular approaches seem to be promising for the detection of these viruses, we developed a simple qualitative RT-PCR procedure for enteroviruses, together with a quantitative RT-PCR assay using RNA internal standard. After one-tube-RT-PCR, this standard and wild enterovirus RNA were detected by differential hybridization with specific probes and a fluorimetric reaction. The quantification of enteroviruses, conducted in a sewage treatment plant, showed a decreasing number of genomic copies from the entrance to the exit (from 3.8 x 10(5) to 5.4 x 10(4) RNA copies/mL) but indicated the presence of enterovirus RNA in the neighboring river (2.2 x 10(3) RNA copies/mL). In bathing areas, enterovirus RNA was detected in 16 out of 226 samples, with copies numbers ranging from 3.7 x 10(2) RNA copies/mL to 7 x 10(4) RNA copies/mL.     

Characterization of Aeromonas spp. isolated from humans with diarrhea, from healthy controls, and from surface water in Bangladesh.

Aeromonas isolates from patients with diarrhea in Bangladesh (n = 69), from healthy controls (n = 11), and from surface water (n = 40) were analyzed with respect to their hybridization groups (HGs) by the aid of fatty acid methyl ester (FAME) characterization and DNA fingerprinting by AFLP, biochemical phenotypes (Phe-nePlate [PhP] types), and the production of hemolysin and cytotoxin. The aim of the investigation was to find out whether certain strains carrying virulence factors predominated among patient isolates. According to FAME and/or AFLP analysis, most human isolates were allocated to DNA HGs 4 (Aeromonas caviae) and 1 (A. hydrophila). Most environmental strains were allocated to HG8 (A. veronii biogroup sobria) and HG4 (A. caviae), and only one was of HG1. According to PhP typing, the diversity among patient isolates was lower than that among other strains, and two dominating PhP types (types BD-1 and BD-2) were identified in 29 and 30% of the patient isolates, respectively. PhP type BD-1 was also common among the environmental isolates, whereas PhP type BD-2 was only identified in two of the other isolates. Twenty-five of 26 isolates belonging to HG1 were of the same PhP type (BD-2), whereas isolates of other common HGs were more diverse according to their PhP types. Hemolytic and cytotoxin-producing strains occurred more frequently among the environmental isolates than among patient isolates. However, the hemolytic and cytotoxic activities among human isolates was strongly correlated to the HG1/BD-2 type, which, in addition, showed high cytotoxin titers (median values, 1/512 compared to 1/128 for cytotoxin-positive isolates belonging to other types). Thus, the HG1/BD-2 type may represent a pathogenic A. hydrophila type that is able to produce diarrhea in humans.     

Exosomes derived from monocytes and from endothelial cells mediate monocyte and endothelial cell activation under high d-glucose conditions

Diabetes mellitus type 2 (DMT2) is characterized by hyperglycemia and associated with low grade inflammation affecting both endothelial cells and monocytes. Exosomes are nanovesicles, allow communication between endothelial cells and monocytes and have been associated with diabetic complications. In this study we evaluated whether high glucose can activate monocytes and endothelial cells and whether exosomes play a role in this activation. Moreover, we studied whether endothelial cells and monocytes communicate with each other via exosomes under high and basal glncubation. In the first experiment, monomac 6 cells (MM6) were exposed to high glucose (HG; 25?mmol/L) or to exosomes from MM6 exposed to HG (exoMM6-HG) or basal glucose (5.5?mmol/L) (exoMM6-BG). In the second experiment, MM6 were exposed to exosomes from human umbilical vein endothelial cells (HUVECs) and HUVECs to exosomes from MM6. In the third experiment, MM6 and HUVECs were exposed to a mixture of exosomes from MM6 and HUVECs (exoMix). Cell activation was evaluated by measuring the protein surface expression of intracellular adhesion molecule-1 (ICAM-1) by flow cytometry. HG increased ICAM-1 expression in MM6 and monocytic exosomes from HG or BG shown similar effect in HG and BG MM6 cells. Exosomes from HUVECs increased ICAM-1 expression in MM6 cells, incubated under HG or BG, while also exosomes from MM6 increased ICAM-1 expression in HUVECs incubated under HG or BG. The combination of exosomes from both cell types (exoMixHG or exoMixBG) also increased ICAM-1 expression in both type cells in most conditions. However, the exoMixBG reversed the effect of HG in both MM6 and HUVECs. Our results show that HG activated monocytes and endothelial cells and that exosomes play a role in this HG-induced cell ICAM-1 expression. We hypothesize that during DMT2, exosomes may act as a communication mechanism between monocytes and endothelial cells, inducing and maintaining activating of both cell types in the presence of high glucose.     

The separation of epinephrine from norepinephrine and dopamine from DOPA on Sephadex G-10

Epinephrine and norepinephrine were separated by acid elution through a Sephadex G-10 column with high recovery (better than 90%), excellent reproducibility, and little overlap (less than 10%). Once packed, the columns could be re-used indefinitely. Total elution time was about six hours and the columns could be left untended since the gravity flow stops automatically once the level of the eluant reaches the gel bed. The resulting dilution was five-fold. 3,4-Dihydroxyphenylalanine (DOPA) was completely separated from 3,4-dihydroxyphenylethylamine (dopamine) by the same procedure.     

Auditory hallucinations: Insights and questions from neuroimaging

Introduction. The human brain has the capacity to hallucinate but rarely, except in severe neuropsychiatric conditions such as schizophrenia, do they naturally predominate. The neural basis of auditory verbal hallucinations (AVHs) has been investigated using structural and functional neuroimaging techniques. So far, no studies have defined a model that explains why auditory hallucinations are perceived in the absence of an external stimulus. Methods. A selective literature review was undertaken specifically to focus on: (1) clinical phenomenology; (2) putative brain systems involved in the pathogenesis of auditory hallucinations as suggested by neuroimaging studies; (3) contributions and weaknesses of the neuroimaging findings in potentially bridging the gap between the neuroscience and phenomenology. Throughout, an attempt was made to ask questions as much as to answer them. Results. Functional domains implicated in the genesis of auditory verbal hallucinations include: (1) hearing and language; (2) “sense of reality”, including externality of voices; (3) attention and salience; (4) emotional response; (5) memory; (6) volition and self-monitoring; (7) impulse control. Each of these domains can be mapped onto neural “systems” that comprise components that overlap with brain regions known to activate during the experience of auditory hallucinations Conclusions. In the next phase of neuroimaging research into the pathogenesis of auditory hallucinations we need to examine component processes that lead to the patient's perception of them as real.     

Adsorption of fibronectin derived from serum and from human endothelial cells onto tissue culture polystyrene

Human endothelial cells (HEC) suspended in a culture medium containing 20% human serum (CMS) adhere and spread on(to) moderately wettable polymers, such as tissue culture polystyrene (TCPS). We have previously shown that serum derived-fibronectin, which is a cell adhesion promoting protein, has a high affinity for TCPS, but that the amount of fibronectin which adsorbed from CMS was relatively small. In this study we investigated whether fibronectin derived from HEC contributes to the adhesion and spreading of the cells on(to) TCPS. Therefore, HEC were seeded in the presence of fibronectin-depleted CMS. The amount of fibronectin detected on TCPS increased with both cell seeding density and incubation time. Although initial HEC adhesion is delayed on TCPS which has been precoated with albumin (Alb), high density lipoprotein (HDL) or immunoglobulin G (IgG), maximal numbers of adhering and spreading HEC were found on these surfaces 6 h after seeding of HEC. Fibronectin was detected on these surfaces, but an exchange of preadsorbed Alb, HDL, or IgG for fibronectin could not be demonstrated. We conclude that HEC deposit fibronectin onto TCPS, irrespective of the presence of a preadsorbed layer of proteins which delay cell adhesion.     

Enterotoxin production by Staphylococcus aureus isolates from cases of septicaemia and from healthy carriers

In a prospective study, 52 Staphylococcus aureus isolates from individual patients with septicaemia and 27 nasal strains from separate, healthy carriers were compared for production of a range of extracellular proteins and toxins. Whereas there was no difference (p greater than 0.05) between septicaemic and nasal isolates with respect to incidence of alpha, beta, gamma and delta haemolysins, toxic shock syndrome toxin-1 or staphylokinase production, the incidence of enterotoxin A, B, and C production was higher among isolates from septicaemia (p less than 0.01). Of the isolates from septicaemia, 33 (63%) produced enterotoxins A, B, C or D alone or in combination. Only three (11%) of the nasal isolates produced a single enterotoxin, enterotoxin D. Of the isolates from septicaemia, 67% were hospital-acquired and greater than 25% of these were endemic, methicillin-resistant (MRSA) strains. All MRSA strains produced either enterotoxin A, or enterotoxin B, or both. These findings suggest a possible role for enterotoxins in the pathogenesis of S. aureus disease other than food poisoning.     

Evaluation of DNA damage in mice topically exposed to total particulate matter from mainstream and sidestream smoke from cigarettes and bidis

The genotoxic potential of total particulate matter (TPM) from mainstream smoke (MS) and sidestream smoke (SS) of Indian smoking products, namely cigarettes and bidis, as well as a brand of US cigarettes, was studied by determining the levels of bulky aromatic DNA adducts in mouse tissues. TPM from MS or SS of various smoking products [equal weights (2.5 mg) or the amount derived from equal (0.25) cigarette/bidi] was applied topically to mouse skin once a day for four consecutive days and adduct levels were determined in DNA from skin and lung by (32)P-post-labelling analysis. Relatively higher levels of bulky aromatic DNA adducts were noted in mouse skin treated with MS from a single Indian non-filter (INF) cigarette when compared with MS of a single bidi (with about half the product weight and one-quarter the tobacco compared with a cigarette), while comparable adduct levels were noted with SS from these two products. Considering the differences in the yields of constituents of tobacco smoke from the different products analyzed, the genotoxic potential of INF, Indian filter king (IFK) and American filter (AF) cigarettes as well as bidis was determined by topically applying an equal amount of TPM (rather than equal product-derived TPM). SS-derived TPM from all the products showed relatively higher levels of total polycyclic aromatic hydrocarbons and induced relatively higher levels of bulky aromatic DNA adducts than those derived from MS. The data indicate that TPM (MS + SS) from cigarettes appears to be more genotoxic than that from bidis and the contribution of tendu leaf (a non-tobacco bidi wrapper) to the generation of bulky aromatic DNA adducts appears to be significant, particularly in SS of bidis. Topical pretreatment with curcumin decreased the levels of TPM-derived adducts while pretreatment with dietary turmeric failed to show such protection.     

Altered basal and adenosine-mediated protein flux from coronary arterioles isolated from exercise-trained pigs

Solute flux per unit surface area and concentration gradient, (J_S/SΔC), was quantified in arterioles isolated from hearts of sedentary (SED) and exercise-trained (EX) female Yucatan Miniature Swine. Apparent permeability (P_S) was assessed from measures of J_S/SΔC for two proteins, α-lactalbumin (α-lact) and porcine serum albumin (PSA), under basal conditions and following 5 min suffusion with 10^?5M adenosine (ADO). Both proteins were labelled with the fluorescent dye tetramethyl rhodamine isothiocyanate. Basal P_s to α-lact differed with exercise training ((P^α-lact_s)_SED=5.2±1.8 (median±median absolute deviation (MAD), n=9 pigs) versus (P^α-lact_s)_EX=7.4±1.1×10^?7 cm s^?1, n=9, P<0.05). For the larger protein PSA, basal P_s did not change with training ((P^PSA_s)_SED=5.0±1.6, N=11 vs. (P^PSA_s)_EX=4.1±1.2×10^?7 cm s^?1, N=11). Suffusion of the arterioles (33±4 μm diameter, n=18 vessels) from SED hearts (n=14) with 10^?5M ADO decreased P^α-lact_s 15±8% relative to control and was without effect on P^PSA_s. By contrast, in arterioles (39±4 μm diameter, n=22 vessels) from EX hearts (n=14), ADO increased P^α-lact_s and P^PSA_s by 32 and 65% respectively, indicating that receptor-mediated changes in permeability were also sensitive to exercise training. These data demonstrate that, for coronary arterioles, permeability to macromolecules adapts to exercise training. The adaptive mechanisms may involve more than one structural component of the vessel wall as the changes in permeability were size-dependent.     

Similarities and differences between interference from stimulus position and from direction of an arrow: Behavioral and event-related potential measures

Studies with stimulus–response compatibility (SRC) tasks used the stimulus position (SRC-p) and/or the direction indicated by a central arrow (SRC-d) as irrelevant dimensions. Despite behavioral differences revealed by the distributional analysis (DA), both interferences were established at similar loci on the basis of modulations in the lateralized readiness potential (LRP) and P3b components. Consequently, similar underlying mechanisms were proposed for both interferences. However, comparison of motor processes associated with each task is problematical because each involves different components. In addition, previous studies have frequently used different proportions of trials between conditions, which complicate interpretation of the results because the stimulus probability may modulate P3b. Taking these problems into account, the present study investigated the effects of interference in SRC-p and SRC-d tasks, in which the participants responded to the color of a stimulus while ignoring the position and the direction indicated by a central arrow, respectively. The interference was greater in the SRC-p than in the SRC-d task. The DA showed that stimulus position affected the performance more quickly than the direction of the arrow. The P3b latency was longer and the P3b amplitude was smaller when stimulus position was incompatible. However, no differences in P3b were found in the SRC-d task. Moreover, both types of interference affected response-related processes (LRP-r) similarly. Therefore, the stimulus position and the direction indicated by the stimulus may share a common locus of interference (response execution), but only stimulus position affects P3b component, which constitutes a link between stimulus evaluation and the response selection.     

Enolases from fluoride-sensitive and fluoride-resistant streptococci.

The enolase from a highly fluoride-sensitive strain of Streptococcus salivarius and its fluoride-resistant mutant, as well as those from strains of Streptococcus sanguis and Streptococcus mutans with intermediate and low sensitivities to fluoride have been shown to be inhibited by fluoride. Comparisons of the purified, strain-specific enzymes showed a high degree of similarity for all preparations. The Michaelis constants for the substrate 2-phosphoglycerate were 1.3 x 10(-4) to 2.4 x 10(-4) M, pH optima were 7.3 to 7.7, and Mg2+ optima were 2 mEq/liter for all. Inhibition by fluoride required the presence of inorganic phosphate and was competitive in nature, and the calculated modified inhibition indices were found to be in the range from 3.3 x 10(-14) to 5.8 x 10(-14) M4. Percent inhibitions were determined under standardized conditions (0.16 mM NaF, 2 mM MgSO4, 0.5 mM Pi, and 0.5 mM 2-phosphoglycerate) and were found to range from 53.3 to 65.9% for all of the purified enzymes. The differences do not appear to be meaningful metabolically. Inhibition was reduced to about 14% at pH 6.0. From the similarities in the behavior of the strain-specific enzymes it is concluded that the differences in the glycolytic sensitivities of the different strains of streptococci to fluoride are not the consequence of any kinetic differences between the respective enolases.