Phagocytosis of alveolar macrophages after conagenin injection to rats

Phagocytic functions of rat alveolar macrophages (AM) following intraperitoneal injection of conagenin (CNG) and of AM sub-populations fractionated by Percoll discontinuous gradient centrifugation were investigated. Phagocytosis of opsonized-sheep red blood cells (SRBC) following in vitro incubation with CNG showed a significant increase in a higher density of AM (fraction IV). In addition, phagocytosis was also increased in lower density ones (fractions I and II) by macrophage-activating factor (MAF) co-cultivation. CNG-injected rats for 5 consecutive days showed a dose-dependent increase in phagocytosis of AM compared to the control rats. Although the distribution of AM sub-population in rats injected CNG was not significantly different compared to the control rats, phagocytosis was significantly increased in AM of a lower density fraction (fraction II). These results suggest that CNG directly increases phagocytosis of AM in a higher density fraction, and indirectly enhances phagocytosis in AM of a lower density fraction via increasing MAF-like material production.

Construction of FLAG and histidine tagging vectors for Schizosaccharomyces pombe

Schizosaccharomyces pombe is becoming an increasingly popular model system for investigating important cellular processes. To facilitate detection, purification and functional studies of Sz. pombe gene products, we constructed two tagging expression vectors for use in Sz. pombe. These vectors allow proteins to be expressed ectopically as fusion proteins with a FLAG epitope and six histidine residue tags attached to their N-terminus or C-terminus. The function and applicability of these vectors were examined and the results are shown using the N-terminal tagging vector encoding Sfc6p, a subunit of the Sz. pombe RNA polymerase III general transcription factor, TFIIIC.

Production of serine protease of Aeromonas sobria is controlled by the protein encoded by the gene lying adjacent to the 3' end of the protease gene

We cloned a protease gene of Aeromonas sobria and determined its nucleotide sequence. The protease is composed of 624 amino acid residues and its calculated molecular weight is 66,737.7. The amino acid sequence showed the characteristic features of a bacterial serine protease. We expressed the protease gene in Vibrio parahaemolyticus from which the synthesized protease is secreted into the culture medium as the mature form, and purified the mature protease by successive column chromatographies. The size of the mature protease is 65,000 daltons and the amino acid sequence analysis revealed that a 24-amino acid peptide at the amino terminal of the precursor is removed from the mature protease. This peptide might function as a signal peptide in translocation across the inner membrane. Subsequently, we found that the protein, designated ORF2 protein, encoded by the gene lying adjacent to the 3' end of the protease gene plays an important role in production of the protease. Mutation of the ORF2 gene did not affect transcription of the protease gene, but resulted in degradation of the protease in the cell. This shows that ORF2 protein is required for the successful production of the serine protease by cell.

Hypoglycemic syncope induced by a combination of cibenzoline and angiotensin converting enzyme inhibitor

A 65-year-old Japanese woman with dilated cardiomyopathy, hypothyroidism and refractory sustained ventricular tachycardia experienced a near-death hypoglycemic syncope. The attack seemed to be induced by a high level of serum insulin, probably due to cibenzoline and by concomitant use of an angiotensin converting enzyme inhibitor (ACEI). Additionally, decreased food intake because of a severe toothache may have contributed to the deterioration of her condition. This case warns cardiologists that a combined cibenzoline and ACEI therapy can provoke serious adverse effects such as hypoglycemic syncope in the elderly. Therefore, the possibility of a hypoglycemic attack associated with these drugs should be explained to patients who are in poor condition.

Effect of beta-blockers on circulating levels of inflammatory and anti-inflammatory cytokines in patients with dilated cardiomyopathy

OBJECTIVES

This study was designed to evaluate the beneficial effect of beta-blockers on circulating cytokine levels in patients with dilated cardiomyopathy (DCM).

BACKGROUND

Elevated circulating levels of inflammatory cytokines have been reported in patients with DCM. However, alterations of the levels of inflammatory and anti-inflammatory cytokines in association with beta-blocker therapy are unknown.

METHODS

We studied 32 patients with idiopathic DCM who had been treated with digitalis, diuretics and angiotensin-converting enzyme inhibitors. In addition to this combination therapy, beta-blockers were started in all patients. Serum levels of interleukin (IL)-10, tumor necrosis factor-alpha (TNF-alpha) and soluble TNF receptors (sTNF-R1 and R2) were measured at baseline and 12 weeks after the initiation of beta-blocker therapy. We also measured plasma levels of neurohumoral factors, as well as left ventricular (LV) size and function. Ten age-matched subjects with no cardiac disease served as the control group.

RESULTS

Baseline levels of IL-10, TNF-alpha and sTNF-R2 were significantly higher in patients with DCM than in control subjects (p < 0.05). There was a significant positive correlation between IL-10 and TNF-alpha levels (r = 0.545, p = 0.029). The TNF-alpha/IL-10 ratio correlated well with plasma epinephrine levels (r = 0.677, p = 0.025), and the level of sTNF-R2 was closely related to LV size. Serum levels of IL-10, TNF-alpha and sTNF-R2 were significantly decreased during beta-blocker therapy (p < 0.005).

CONCLUSIONS

Our findings indicate that beta-blockers have an important immunoregulatory role in modifying the dysregulated cytokine network in DCM. This effect of beta-blockers may be partly responsible for the efficacy of therapeutic drugs for heart failure.

Lack of effect of the abnormal fatty acid metabolism in NC/Nga mice on their atopic dermatitis

Although clinical evidence has suggested that dysregulated fatty acid metabolism is associated with atopic disorders, the molecular basis for such a correlation remains to be demonstrated. In the present study, we analyzed the fatty acid composition in peripheral blood cells of NC/Nga mice, a model for atopic dermatitis (AD). We found that arachidonic acid significantly accumulated in mice with the AD manifestation. In addition, the leucotriene B4-releasing ability upon calcium ionophore A23187 stimulation was potentiated in blood cells. An arachidonic acid accumulation was not apparent in the non-atopic BALB/c strain, but was still observed in healthy NC/Nga mice fed under specific pathogen-free conditions. These results indicate that a disturbed fatty acid metabolism in NC/Nga mice was not a trigger factor for their dermatitis development.

Immunoblotting detection of gamma-catenin (plakoglobin) antibody in the serum of a patient with paraneoplastic pemphigus

We report a patient with paraneoplastic pemphigus associated with a thymic tumour. Immunoblot study using affinity-purified gamma-catenin protein revealed that his serum recognized gamma-catenin (plakoglobin) in epidermal, thymic tumour and mouse bladder extracts.

Molecular recognition by chiral cationic micellar and micelle-like aggregates in electrokinetic capillary chromatography

We examined the enantiomer separation with micelles and a micelle-like polymer made with trimethylammonium-terminated surfactants all of whose hydrocarbon chains contain hydrogen bonding valinediamide moieties in electrokinetic chromatography (EKC). The surfactants used were 3-(N-dodecanoyl-L-valylamino)-propyltrimethylammonium bromide (surfactant 1) and 6-(N-nonanoyl-L-valylamino)hexyl-trimethylammonium bromide (surfactant 2); the micelle-like polymer was derived from 3-(N-10-undecenoyl-L-valyl)aminopropyltrimethylammonium bromide (surfactant 3). N-Acylamino acids and their isopropyl esters were separated with enantiomers with the same configuration as the chiral surfactant and which were retained to a greater extent than the counterparts in micelles. The micellar hydrophobic environment, in which amides function as hydrogen bonding sites with solutes, and ceased micellar kinetic association-dissociation with polymerization are discussed.

Coronary spastic angina induced by anticholinesterase medication for myasthenia gravis--a case report

Myasthenia gravis (MG) is characterized by weakness of skeletal muscles because of a decrease in the number of available acetylcholine receptors at neuromuscular junctions. Anticholinesterase medication is widely used to treat MG, but muscarinic side effects sometimes appear and limit the drug usage. To their knowledge, the authors present the first case of coronary spastic angina quite possibly induced by anticholinesterase medication to treat MG. The appearance of coronary spastic angina in the present case is likely mediated through the increase of acethylcholine by anticholinesterase medication.

Time-course changes in left ventricular geometry and function during the development of hypertension in Dahl salt-sensitive rats

Serial changes of left ventricular (LV) geometry and function during the development of hypertension were studied in 50 Dahl salt-resistant (DR) and 88 Dahl salt-sensitive (DS) rats fed an 8% NaCl diet beginning at the age of 6 weeks. Echocardiography at 6, 8, 11, 13, 14, 15, and 18 weeks and in vivo invasive hemodynamic determination at 6, 8, 11, 14, and 18 weeks were performed. After 11 weeks, 33 DS rats were observed for survival analysis. The survival analyses showed that the incidence of death was 57.6% due to heart failure, 27.3% due to stroke, and 15.2% due to sudden death. However, death in the early stages of hypertension was due almost entirely to sudden death or stroke. A high value of relative wall thickness (RWT) and a small end-diastolic dimension were predictive of sudden death and stroke, but LV mass (LVM) was not. Concerning the change in LV geometric patterns, LVM continued to increase to 18 weeks. The RWT increased or remained at a plateau up to 13 weeks, and then progressively decreased after 13 weeks. In contrast, LV function was hyperdynamic between 8 and 11 weeks when compared to DR rats. However, after 13 weeks, all hemodynamic variables of DS rats deteriorated progressively, and all DS rats died of heart failure. Thus, our study indicates that the cardiovascular events associated with the progression of hypertension vary widely according to the stage of hypertension and that RWT is more sensitive in predicting LV conditions than LVM in hypertension.

Aortic distensibility is closely related to the progression of left ventricular hypertrophy in patients receiving hemodialysis

Aortic stiffening and left ventricular hypertrophy are believed to be major determinants for the prognosis of patients with end-stage renal disease. However, the relationship between left ventricular hypertrophy and aortic stiffness remains to be determined. Echocardiographically determined parameters and aortic distensibility determined with cine magnetic resonance were evaluated in 21 patients undergoing chronic hemodialysis. Hemodynamic variables measured at the beginning of the study were compared with those measured after 28 months. Aortic distensibility determined at the descending aorta was markedly lower in patients undergoing hemodialysis than in healthy control subjects. During the follow-up period, blood pressure and hemodynamic variables, including left ventricular mass index, remained unchanged. However, multiple regression analysis indicated that aortic distensibility independently contributed to the left ventricular mass index and to the change in left ventricular mass index between baseline and after 28 months. Baseline left ventricular mass index negatively correlated to aortic distensibility (r = -0.74, p < 0.0001), and the changes in left ventricular mass index positively correlated to aortic distensibility (r = 0.52, p < 0.05). Our study demonstrates that aortic distensibility at the descending aorta is a predictable marker for the development or regression of left ventricular hypertrophy. Therefore, patients with end-stage renal disease must be treated with appropriate drugs to improve aortic distensibility.

Pruritus and hydration state of stratum corneum in hemodialysis patients

BACKGROUND

Xerosis is the most frequent cutaneous manifestation in hemodialysis (HD) patients, but the association between dry skin and pruritus remains to be clarified. Since the skin surface hygrometer can detect the changes of water content in the stratum corneum more sensitively, we re-examined the relationship between the severity of pruritus and water content in dialysis patients.

METHODS

Fifty patients who had been undergoing regular HD were examined for the degree of pruritus by clinical grading. Water contents in the stratum corneum at volar forearm and lower leg were assessed by measurement of high-frequency conductance using a skin surface hygrometer both at pre- and postdialysis.

RESULTS

Thirty-seven (74%) of dialysis patients complained of pruritus. High-frequency conductance values were significantly lower in HD patients compared to those of age-matched control subjects (n = 13) both at forearm (35.1+/-3.0 vs. 73.3+/-10.4 microS, p<0.01) and lower leg (14.2+/-1.1 vs. 52.4+/-7.5 microS, p<0.01). There was no relationship between the severity of pruritus and age, gender, HD duration, underlying renal disease, or removing fluid volume. A significant reduction of itching score was found in patients using polysulfone membrane. A single HD session using cellulose triacetate or polysulfone membrane significantly increased water content both at forearm and lower leg (p<0.05). However, the degree of pruritus did not correlate with the skin water content both at the beginning and the end of HD session, respectively.

CONCLUSION

It follows from these findings that water content in the stratum corneum was reduced in HD patients, but did not correlate with the severity of pruritus.

Gastrointestinal stromal tumors of the small intestine that expressed c-kit protein

We report two patients with gastrointestinal stromal tumors (GISTs) of the small intestine that expressed c-kit protein (CD117). One was a 68-year-old woman with epigastralgia and vomiting. A submucosal tumor of the upper jejunum was detected, and partial resection was carried out. The histology revealed a GIST negative for CD34 but positive for CD117. The other was a 42-year-old woman with progressive anemia, melena and lower abdominal pain. Intussusception was detected, and a partial resection was carried out. A submucosal tumor of the lower jejunum was noted. The histology revealed a GIST positive for both CD34 and CD117.

E-73, an acetoxyl analogue of cycloheximide, blocks the tumor necrosis factor-induced NF-kappaB signaling pathway

Proinflammatory cytokines such as tumor necrosis factor (TNF) and interleukin (IL)-1 activate the NF-kappaB signaling pathway which induces the expression of a variety of genes such as the encoding intercellular adhesion molecule (ICAM)-1. We have found that E-73, an acetoxyl analogue of cycloheximide, specifically blocks TNF-induced ICAM-1 expression even at concentrations unable to affect protein synthesis. By contrast, cycloheximide inhibited both TNF- and IL-1-induced ICAM-1 expression primarily due to the blockage of protein synthesis. The nuclear translocation of NF-kappaB as well as the IkappaB degradation induced by TNF, but not by IL-1, was significantly prevented by E-73. These observations suggest that E-73 blocks the TNF-induced NF-kappaB signaling pathway upstream of IkappaB degradation.

Isolation and cloning of four subunits of a fission yeast TFIIIC complex that includes an ortholog of the human regulatory protein TFIIICbeta

Eukaryotic tRNA genes are controlled by proximal and downstream elements that direct transcription by RNA polymerase (pol) III. Transcription factors (TFs) that reside near the initiation site are related in Saccharomyces cerevisiae and humans, while those that reside at or downstream of the B box share no recognizable sequence relatedness. Human TFIIICbeta is a transcriptional regulator that exhibits no homology to S. cerevisiae sequences on its own. We cloned an essential Schizosaccharomyces pombe gene that encodes a protein, Sfc6p, with homology to the S. cerevisiae TFIIIC subunit, TFC6p, that extends to human TFIIICbeta. We also isolated and cloned S. pombe homologs of three other TFIIIC subunits, Sfc3p, Sfc4p, and Sfc1p, the latter two of which are conserved from S. cerevisiae to humans, while the former shares homology with the S. cerevisiae B box-binding homolog only. Sfc6p is a component of a sequence-specific DNA-binding complex that also contains the B box-binding homolog, Sfc3p. Immunoprecipitation of Sfc3p further revealed that Sfc1p, Sfc3p, Sfc4p, and Sfc6p are associated in vivo and that the isolated Sfc3p complex is active for pol III-mediated transcription of a S. pombe tRNA gene in vitro. These results establish a link between the downstream pol III TFs in yeast and humans.

Tubelactomicin A, a novel 16-membered lactone antibiotic, from Nocardia sp. I. Taxonomy, production, isolation and biological properties

A novel 16-membered lactone antibiotic named tubelactomicin A was isolated from the culture broth of an actinomycete strain. The producing organism, designated MK703-102F1, was identified as a member of Nocardia. Tubelactomicin A was isolated from the culture broth by Diaion HP20 absorption, ethyl acetate extraction, silica gel and Sephadex LH-20 column chromatographies and centrifugal liquid-liquid partition chromatography (CPC). Tubelactomicin A showed strong activity against acid-fast bacteria including the drug-resistant strains.

Migrastatin, a new inhibitor of tumor cell migration from Streptomyces sp. MK929-43F1. Taxonomy, fermentation, isolation and biological activities

A new compound, migrastatin, was isolated from a cultured broth of Streptomyces sp. MK929-43F1, as an inhibitor of tumor cell migration. It was purified by column chromatographies on silica gel and Sephadex LH-20 and HPLC. Migrastatin has the molecular formula of C27H39NO7 consisting of 14-membered macrolide and glutarimide moiety. It inhibited spontaneous migration of human esophageal cancer EC17 cells. Migration inhibitory activity of migrastatin was not dependent on cytotoxicity or inhibition of protein synthesis.

Nonunited avulsion fractures of the intercondylar eminence of the tibia

We report 3 cases of nonunited avulsion fracture of the intercondylar eminence of the tibia. Characteristics of the clinical symptoms were limitation of knee extension, pain at knee extension, and a small amount of anterior instability. For the patient with a normal anterior cruciate ligament (ACL), the fragment was fixed by sutures with a button after curettage of the fibrous tissue. Two patients underwent endoscopic ACL reconstruction using quadrupled semitendinosus tendon because their ACLs had degenerated. Since the technique of ACL reconstruction under arthroscopic control has been well refined, endoscopic ACL reconstruction is considered to be 1 of the surgical options for nonunited avulsion fracture with symptomatic anterior instability if the ACL is degenerated.

Transcription termination by RNA polymerase III in fission yeast. A genetic and biochemically tractable model system

In order for RNA polymerase (pol) III to produce a sufficient quantity of RNAs of appropriate structure, initiation, termination, and reinitiation must be accurate and efficient. Termination-associated factors have been shown to facilitate reinitiation and regulate transcription in some species. Suppressor tRNA genes that differ in the dT(n) termination signal were examined for function in Schizosaccharomyces pombe. We also developed an S. pombe extract that is active for tRNA transcription that is described here for the first time. The ability of this tRNA gene to be transcribed in extracts from different species allowed us to compare termination in three model systems. Although human pol III terminates efficiently at 4 dTs and S. pombe at 5 dTs, Saccharomyces cerevisiae pol III requires 6 dTs to direct comparable but lower termination efficiency and also appears qualitatively distinct. Interestingly, this pattern of sensitivity to a minimal dT(n) termination signal was found to correlate with the sensitivity to alpha-amanitin, as S. pombe was intermediate between human and S. cerevisiae pols III. The results establish that the pols III of S. cerevisiae, S. pombe, and human exhibit distinctive properties and that termination occurs in S. pombe in a manner that is functionally more similar to human than is S. cerevisiae.

A 25-year-old patient with low cardiac risk factors having a combination of variant angina and severe coronary arterial lesions--a case report

A 25-year-old man with low cardiac risks underwent coronary arteriography because of chest pain at rest. His only risk factors for coronary artery disease was smoking. Both right and left coronary arteries were ectatic and the left anterior descending artery was obstructed. In the acetylcholine provocation test, the left circumflex coronary artery showed severe constriction. Thus, this patient was diagnosed as having a combination of variant angina and occlusive coronary artery disease.

New triene-ansamycins, thiazinotrienomycins F and G and a diene-ansamycin, benzoxazomycin

New triene-ansamycins designated thiazinotrienomycins F (TT-F) and G (TT-G) and a new diene-ansamycin, benzoxazomycin, were isolated from a culture broth of Streptomyces sp. MJ672-m3 and their structures were elucidated by spectroscopic analyses. The Mean Graphs of TT-G suggests that the tumor growth inhibitory activities are almost as strong as TT-B, in respect of GI50 and TGI against several human cancer cell lines.

The gravity sag view: a simple radiographic technique to show posterior laxity of the knee

We introduce a simple radiographic technique of taking a "gravity sag view" to show sagittal laxity secondary to posterior cruciate ligament injury. Side-to-side differences of the tibia-femur step-off measured with these radiographs have proved to be useful parameters for evaluating posterior laxity. This radiographic technique is recommended instead of routine lateral radiographs taken with the knee kept recumbent.

The steady-state kinetics of the enzyme reaction tested by site-directed mutagenesis of hydrophobic residues (Val, Leu, and Cys) in the C-terminal alpha-helix of human adenylate kinase

To elucidate whether the C-terminal region in human adenylate kinase participates in the interaction with the substrate (MgATP(2-) and/or AMP(2-)), hydrophobic residues (Val182, Val186, Cys187, Leu190, and Leu193) were substituted by site-directed mutagenesis and the steady-state kinetics of fifteen mutants were analyzed. A change in the hydrophobic residues in the C-terminal domain affects the affinity for substrates (K(m)), that is, not only for MgATP(2-) but also for AMP(2-), and the catalytic efficiency (k(cat)). The results obtained have led to the following conclusions: (i) Val182 may interact with both MgATP(2-) and AMP(2-) substrates, but to a greater extent with MgATP(2-), and play a role in catalysis. (ii) Val186 appears to play a functional role in catalysis by interacting with both MgATP(2-) and AMP(2-) to nearly the same extent. (iii) Cys187 appears to play a functional role in catalysis. (iv) Leu190 appears to interact with both MgATP(2-) and AMP(2-) substrates but to a greater extent with AMP(2-). (v) Leu193 appears to interact with both MgATP(2-) and AMP(2-) but to a greater extent with AMP(2-). The activity of all mutants decreased due to the change in substrate-affinity. The closer the residue is located to the C-terminal end, the more its mutation affects not only MgATP(2-) but also AMP(2-) substrate binding. The hydrophobic alterations disrupt hydrophobic interactions with substrates and that might destabilize the conformation of the active site. The more C-terminal part of the alpha-helix appears to interact with AMP, as if it has swung out and rotated to cover the adenine moieties. The C-terminal alpha-helix of human adenylate kinase appears to be essential for the interaction with adenine substrates by swinging out during catalysis.

Selection of intracellularly active ribozymes in mammalian cells

Ribozymes are expected to be useful as antiviral agents and powerful tools of functional analysis of unknown gene products in vivo. For use of ribozymes in vivo, they must be fully functional in the intracellular environment. Not all ribozymes selected in vitro would be expected to work in vivo, whereas ribozymes selected in the intracellular environment should retain their function in vivo. With the eventual aim of using ribozymes as antiviral agents or biological tools in mammalian cells, we then devised a novel selection system in mammalian cells of active ribozymes by targeting at a gene for the cyclin dependent kinase inhibitor (CDKI), p16INK4a. In this system, we found that p16INK4a-knockdown cells became malignant and they formed foci. In the mammalian system, we confirmed that the selected cells harbored the active ribozyme, indicating that our positive selection systems in vivo were operational.

Leukocyte-depleted reperfusion after long cardioplegic arrest attenuates ischemia-reperfusion injury of the coronary endothelium and myocardium in rabbit hearts

OBJECTIVE

Cardiopulmonary bypass activates leukocytes, which should injure the coronary endothelium and myocardium during reperfusion especially after long cardioplegic arrest with long cardiopulmonary bypass time. The present study was designed to determine the protective efficacy of leukocyte-depleted reperfusion in blood-perfused parabiotic isolated rabbit hearts as a surgically relevant model with long cardioplegic arrest.

METHODS

Each isolated rabbit heart, with a latex balloon inserted in the left ventricle, was parabiotically blood-perfused using a modified Langendorff column. The left ventricular developed pressure (DP), rate of pressure development (dP/dT), and coronary flow with a left ventricular end-diastolic pressure of 10 mmHg were measured before ischemia and after 15, 30, 45, and 60 min reperfusion after 4 h cardioplegic arrest kept at 20 degrees C (control, n=10). Leukocyte-depleted reperfusion was done in the test group (n=10). The endothelium of the coronary artery was observed by scanning electron microscopy (SEM) with percent injured area of endothelial cells measured to evaluate the extent of endothelial ischemia-reperfusion injury.

RESULTS

The control hearts showed 53.3, 54.3, 48.4, and 39.0% recovery of DP compared to the pre-ischemia baseline data at 15, 30, 45, and 60 min after reperfusion began respectively. Leukocyte-depleted reperfusion enhanced the recovery of DP at 45 min (81.3%, P=0.0021) and 60 min (85.8%, P=0.0005) after reperfusion compared with that in the control group. The control hearts revealed 58.8%, 59.8%, 52.6%, and 43.4% recovery of dP/dT compared to the pre-ischemia baseline data at 15, 30, 45, and 60 min after reperfusion began, respectively. Leukocyte-depleted reperfusion also enhanced the recovery of dP/dT at 45 min (93.2%, P=0.0071) and 60 min (98.8%, P=0.0011) after reperfusion compared with that in the control group. There was also improvement of the recovery of coronary flow by leukocyte-depleted reperfusion (97.2%) compared with that in the control group (58.3%) after 60 min reperfusion (P=0.0121). Scanning electron microscopy showed that 69. 7% of coronary endothelial cells were morphologically injured in the control group. In contrast, leukocyte-depleted reperfusion prevented the extent of coronary endothelial damage with less injured area (0. 5%, P=0.0002).

CONCLUSIONS

Leukocyte-depleted reperfusion improved functional recovery with reduced coronary endothelial injury after long cardioplegic arrest.