The potential role of lung epithelial cells and beta-defensins in experimental latent tuberculosis.

Mycobacterium tuberculosis is a facultative intracellular pathogen capable of producing both progressive disease and latent infection. Latent infection is clinically asymptomatic and is manifested only by a positive tuberculin test or a chest radiograph that shows scars or calcified nodules indicative of resolved primary tuberculosis infection. In this study, we used a well-characterized model of latent tuberculosis infection in B6D2F1 mice to compare the production of beta-defensin-3 by infected bronchial epithelial cells and macrophages. We demonstrated by immunolectronmicroscopy that M. tuberculosis can actually infect epithelial cells and induce significant higher production of beta-defensin-3 associated to mycobacteria than infected macrophages. These results demonstrate that lung epithelium harbour mycobacteria during experimental chronic infection; being a possible reservoir of latent mycobacteria in vivo, beta-defensins might participate in bacilli killing or dormancy induction.

Effects of histidine residues on adsorption equilibrium of peptide antibodies.

Histidine and arginine residues in a peptide, which represent residues 112-121 of myoglobin, were replaced by alanine, and antibodies for these peptides were raised in rabbits. Adsorption equilibria between these peptides and antibodies were measured to identify the essential amino acid residues for specific binding and their effects on adsorption behavior. Protonation of one histidine residue affected strongly the dependence of adsorption equilibrium on pH, and the adsorption capacities of the antibodies against the peptides containing this essential histidine residue rapidly decreased at around pH 5-6, which corresponds to the pKa value of histidine. Immunization with peptide sequences containing such histidine residues is one method to obtain suitable antibodies for immunoaffinity chromatography, which have a weak affinity for the elution step under mild conditions.

Pulmonary perfusion during lung transplant rejection and experimental pneumonia.

Six left lung allotransplants were performed in healthy mongrel dogs. Immunosuppression was established with cyclosporine (15 mg/kg/day p.o.) from the day of transplantation for 30 days. Another group of animals (n = 3) was used to produce acute experimental pneumonia by instilling 4-6 ml of a 10(8) CFU suspension of Pseudomonas aeruginosa into the right lower lobe. Dynamic perfusory lung scintigraphy (DPLS) was performed before transplant/pneumonia (control), during acute rejection/pneumonia as detected radiologically, and after treatment with methylprednisolone (1 g/day for 3 days i.v.) (transplant group) or antibiotics (pneumonia group). Seroalbumin macroaggregates (5-8 McI) marked with 99-mTc were injected into the cephalic vein and the percentage of perfusion to each lung was determined. Eight acute rejection episodes were detected. DPLS showed similar perfusion to each lung, whereas during acute rejection perfusion was significantly reduced by almost 30%. Perfusion was reestablished to control levels after treatment with methylprednisolone. Reduction in perfusion correlated with radiological rejection grading. No reduction in left lung perfusion was detected in pneumonia animals. In conclusion, acute rejection reduces perfusion to the transplanted lung as measured by DPLS. Treatment restores normal perfusion.

Characterization of Leptospira strains HY-1, HY-2, and HY-10 isolated in Korea by means of monoclonal antibodies and restriction endonuclease DNA analysis.

To analyze the characteristics of Leptospira strains HY-1, HY-2, and HY-10, which were isolated from patients with leptospirosis in Korea in 1985, 12 monoclonal antibodies (MAbs) against strain HY-1 and six MAbs against serovar lai strain 017 were produced, and their properties were determined by the microscopic agglutination test. Genetic relationships among the leptospires were determined by restriction endonuclease DNA analysis. Three MAbs reacted with all strains of serogroup Icterohaemorrhagiae, but did not react with any strains of the other 10 serogroups. All MAbs reacted with strains 017, HY-1, HY-2, and HY-10 at nearly identical titers. Two MAbs reacted only with these four strains. These four strains also had the same restriction endonuclease cleavage patterns. Based on these results, strains HY-1, HY-2, and HY-10 were identified as serovar lai, which is one of the common serovars in China. It is suggested that serovar lai is one of the prevalent serovars in Korea, and that the Mabs produced in this study are useful for the accurate and rapid identification of this serovar.

A new cutaneous nerve fiber connection with the frontal nerve in the frog Rana esculenta: a morphological study.

The frontal nerve arises from the frontal organ, which represents the extracranial component of the pineal complex in some lower vertebrates, and interconnects the frontal organ with the epiphysis and the brain. The existence of a previously unreported nerve branch of the frontal nerve is described here in the frog Rana esculenta and called the lateral nerve. The course of the lateral nerve and its junction with the frontal nerve have been consistently detected by means of different techniques: toluidine blue staining in semithin sections, the Landau-Ignesti method for myelinated nerve fibers, the methylene blue intravital staining for peripheral nerves, and in vitro tracing with the carbocyanine Dil. A method to preserve intact the delicate lateral nerve during dissection is also described. The lateral nerve was consistently found to be unilateral, and to join the frontal nerve at one end (either on the left or the right side), whereas the other extremity was found to be dispersed in the dermis. Thus, the lateral nerve could represent a new pathway interconnecting the skin and the brain and/or the frontal organ in the frog.

Effects of surface charges and cholesterol content on amino acid permeabilities of small unilamellar vesicles.

The permeabilities of amino acids through bilayer lipid membranes were determined using small unilamellar vesicles (SUV). Alanine, lysine, arginine, and glutamate show permeabilities on the order of 10(-10)-10(-11) cm/s in the case of SUV prepared from dimyristoylphosphatidylcholine and dicetylphosphate. An increase in the amount of negative charges introduced by dicetylphosphate enhanced the permeability of the positively charged amino acid (i.e., lysine). The permeabilities of net charged amino acids decreased with an increase in cholesterol content, and became less than 10(-12) cm/s with the membrane which consists of equimolar amounts of dimyristoylphosphatidylcholine and cholesterol.

Application of stable isotope ratio analysis to the characterization of the geographical origin of olive oils.

To gain information about the geographical origin of oil samples, measurements of delta(13)C and delta(18)O of the whole oil and some of its fractions have been performed on samples coming from fruits of Olea europaea L. produced in Greece, Morocco, Spain, Italy, Tunisia, and Turkey. The results obtained by applying statistical procedures have given pieces of evidence that oil samples have shown the trend to cluster according to the different climatic areas of growing environment of fruits. Some confusion has been observed for samples coming from neighboring countries having similar climates.

Enhanced wear resistance of ball-and-socket joints of dental implants by means of titanium gaseous nitriding.

The aim of this research is the surface hardening of the ball-and-socket joint of dental implants by means of heat treatments in order to obtain titanium nitrides. These nitrides minimize the wear of the titanium used in prosthesis. In this paper the optimum heat treatment, the hardness and the wear resistance are described in relation to the ball-and-socket joint without heat treatment.

Effects of arachidonic acid concentration on prostaglandin biosynthesis and feasibility of semibatch processes.

The reaction characteristics of prostaglandin E2 biosynthesis by PGH-synthase and PGE2 isomerase and the substrate dependency of this biosynthesis were studied. The activity of PG-synthases was blocked by the inhibitory action of one or more byproducts, probably resulting from the action of PGH-synthase. This inhibitory action then appeared to be partly reversible, indicating that the substrate and the inhibitor compete for the catalytic sites. According to these findings, the feasibility of a successful semibatch biosynthesis was investigated. A combination of the substrate concentration reducing procedure and the semibatch process resulted in an about 3.5-fold higher increase in the total amount of PGE2 formed in comparison with the batch results obtained at the substrate concentration of 1.0 mg/cm3. Since the cost of enzyme is a governing factor in this biosynthesis, development of semibatch biosynthesis of PGE2 becomes a matter of economic importance.

Recognition of liposome-bound antigens by antipeptide antibody.

In order to clarify the effects of the differences in physical states of antigens on recognition by antibodies in immunoassays, the binding characteristics of an antipeptide polyclonal antibody to the peptide and the corresponding protein were studied. The reactivity in the immunoliposome assay (ILA), as well as in the double-antibody sandwich ELISA, was identical to that in the solution. These results indicate that the conformation of liposome-bound antigen is changed little by coupling to liposomes and is almost the same as that of the native antigen in the liquid phase. It is desirable to assay by double-antibody sandwich ELISA or ILA to detect native proteins, and the latter is very easily performed.

[Pancreatic cystic fibrosis in Mexicans over 15 years of age]. / Fibrosis quística en páncreas en mayores de 15 años en población mexicana.

A better knowledge of cystic fibrosis of the pancreas has contributed to raise the detection of cystic fibrosis in adults. We describe nine Mexican patients older than 15 years with cystic fibrosis. Respiratory symptoms were predominant and they were secondary to bronchiectasis. All patients were infected by mucoid Pseudomona aeruginosa and in some cases, the finding of this microorganism in sputum suggested the diagnosis. In Mexican population the cystyc fibrosis of the pancreas can be found in adult patients, and it should be considered in the differential diagnosis of chronic respiratory diseases in adults.

Evaluation of enzyme linked immunosorbent-assay and western blot for diagnosis of histoplasmosis.

This study evaluates the use of a enzyme linked immunosorbent assay (ELISA) for the diagnosis of histoplasmosis and it compares it with a complement fixation test. The results showed a sensitivity of 86% in this diagnosis of acute pulmonary histoplasmosis and specificity of 91% using anti-human IgG. For antihuman IgM the sensitivity was 66% and the specificity 100%. There was a good correlation between the titer of complement fixation test and the optical density index by ELISA. Neither ELISA or complement fixation were useful for the diagnosis of disseminated histoplasmosis in immunocompromised patients. Using Western blot we identified antibodies against four different histoplasma antigens (91, 83, 70 and 38 kD) in sera from patients with histoplasmosis. These antigens were identified also in patients with disseminated histoplasmosis. We conclude that ELISA is a useful test for the diagnosis of histoplasmosis, and the Western blot could be useful for the diagnosis of disseminated histoplasmosis.

[Eosinophilic leukemia with cyclic eosinophilic leukocytosis].

A 36-year-old male was admitted to the Ehime University Hospital with anemia, eosinophilia and hepatosplenomegaly. Peripheral blood examination demonstrated severe anemia (Hb 7.1g/dl), thrombocytopenia (Plt 6.8 x 10(4)/microliters) and increase of peripheral leukocyte counts (53,000/microliters) with 32.0% of eosinophils which had lobulated nuclei, abnormal distribution of eosinophilic granules and a few vacuoles. The level of serum IgE was low (< 5IU/ml), while that of serum vitamin B12 was elevated. A diagnosis of eosinophilic leukemia was made. He was noted to have spontaneous fluctuations in his eosinophil and total leukocyte counts. To analyze the mechanism of cyclic eosinophilic leukocytosis, we examined eosinophil colony stimulating activity of the serum and plasma of the patient. These examination showed that eosinophil colony-stimulating activity was not found in his serum and plasma, and cyclic eosinophilic leukocytosis was due to the hemopoietic stem cell disorder.

Cardiac responses to ß-adrenoceptor stimulation is partly dependent on mitochondrial calcium uniporter activity.

BACKGROUND AND PURPOSE: Despite the importance of mitochondrial Ca(2+) to metabolic regulation and cell physiology, little is known about the mechanisms that regulate Ca(2+) entry into the mitochondria. Accordingly, we established a system to determine the role of the mitochondrial Ca(2+) uniporter in an isolated heart model, at baseline and during increased workload following ß-adrenoceptor stimulation. EXPERIMENTAL APPROACH: Cardiac contractility, oxygen consumption and intracellular Ca(2+) transients were measured in ex vivo perfused murine hearts. Ru360 and spermine were used to modify mitochondrial Ca(2+) uniporter activity. Changes in mitochondrial Ca(2+) content and energetic phosphate metabolite levels were determined. KEY RESULTS: The addition of Ru360 , a selective inhibitor of the mitochondrial Ca(2+) uniporter, induced progressively and sustained negative inotropic effects that were dose-dependent with an EC50 of 7 µM. Treatment with spermine, a uniporter agonist, showed a positive inotropic effect that was blocked by Ru360 . Inotropic stimulation with isoprenaline elevated oxygen consumption (2.7-fold), Ca(2+) -dependent activation of pyruvate dehydrogenase (5-fold) and mitochondrial Ca(2+) content (2.5-fold). However, in Ru360 -treated hearts, this parameter was attenuated. In addition, ß-adrenoceptor stimulation in the presence of Ru360 did not affect intracellular Ca(2+) handling, PKA or Ca(2+) /calmodulin-dependent PK signalling. CONCLUSIONS AND IMPLICATIONS: Inhibition of the mitochondrial Ca(2+) uniporter decreases ß-adrenoceptor response, uncoupling between workload and production of energetic metabolites. Our results support the hypothesis that the coupling of workload and energy supply is partly dependent on mitochondrial Ca(2+) uniporter activity.