Lymphotoxins and cytomegalovirus cooperatively induce interferon-beta, establishing host-virus détente

Tumor necrosis factor (TNF)-related cytokines regulate cell death and survival and provide strong selective pressures for viruses, such as cytomegalovirus (CMV), to evolve counterstrategies in order to persist in immune-competent hosts. Signaling by the lymphotoxin (LT)-beta receptor or TNF receptor-1, but not Fas or TRAIL receptors, inhibits the cytopathicity and replication of human CMV by a nonapoptotic, reversible process that requires nuclear factor kappa B (NF-kappa B)-dependent induction of interferon-beta (IFN-beta). Efficient induction of IFN-beta requires virus infection and LT signaling, demonstrating the need for both host and viral factors in the curtailment of viral replication without cellular elimination. LT alpha-deficient mice and LT beta R-Fc transgenic mice were profoundly susceptible to murine CMV infection. Together, these results reveal an essential and conserved role for LTs in establishing host defense to CMV.

Novel sigmaF-dependent genes of Escherichia coli found using a specified promoter consensus

Availability of whole genome information opens new bioinformatics approaches to study global regulation. We developed a program, named ScanProm, that allows to search a genome database for promoter consensus elements. The program uses a multiple alignment of previously identified components of a regulon as an input and generates a consensus profile. The profile is then optimized by adjusting the cutoff value for position-specific similarity assessment and used for a genome scan to search for unknown members of the regulon. The candidates obtained are scored by their similarity to the consensus profile. The ScanProm program was applied to search for novel members of the class III flagellar regulon of Escherichia coli. The search template included the previously defined 4 bp (-35) and 8 bp (-10) promoter elements, presumably recognized by the flagellar-specific sigmaF, with additional 4 bp at the 3' of the -35 consensus. The majority of highly scoring candidates obtained from the whole genome sequence scan were known class III genes, although several new genes were also identified. We tested 10 novel highly scoring candidate class III genes by cloning their promoter fragments into a fusion vector designed to monitor the transcriptional activity with lacZ. Two of these genes, b2737(ygbK) and ppdAB, were found to be dependent on FlhDC, the master regulator of the flagellar genes. The regulation of these genes by sigmaF was further confirmed by comparing their expression in the wild-type and fliA backgrounds. An overproduction or inactivation of these genes did not exhibit any notable phenotypes in motility or chemotaxis.

Bob1, a Gim5/MM-1/Pfd5 homolog, interacts with the MAP kinase kinase Byr1 to regulate sexual differentiation in the fission yeast, Schizosaccharomyces pombe

The MAPKK Byr1 is an essential component of a Ras-dependent MAPK module required for sexual differentiation in the fission yeast, Schizosaccharomyces pombe. Here we describe the genetic and molecular characterization of a highly conserved protein, Bob1, which was identified from a two-hybrid screen for Byr1-interacting proteins. Byrl and Bobl proteins coprecipitate from S. pombe cell lysates, and both proteins localize to the tips and septa of S. pombe cells. S. pombe bob1 null (bob1delta) mutants lack obvious growth defects but exhibit a significant mating deficiency, which can be suppressed by overexpression of Byrl. Overexpression of Bob1 also leads to inhibition of mating in S. pombe, and this defect is likewise suppressed by Byrl overexpression. Bob1 is highly homologous in structure to the mammalian MM-1/Pfd5 and budding yeast Gim5/Pfd5-Sc proteins, which have been implicated as regulators of actin and tubulins. Similar to budding yeast gim5/pfd5-Sc mutants, S. pombe bob1delta cells have cytoskeletal defects, as judged by hypersensitivity to cytoskeletal disrupting drugs. byr1delta mutants do not share this characteristic with bob1delta mutants, and byr1delta bob1delta mutants are not significantly more sensitive to cytoskeletal disrupting drugs than cells carrying only the bob1delta mutation. Taken together, our results suggest that Bob1 has Byr1-related function(s) required for proper mating response of S. pombe cells and Byrl-independent function(s) required for normal cytoskeletal control. We show that the human MM-1/Pfd5 protein can substitute for its counterpart in fission yeast, providing evidence that the functions of Bob1-related proteins have been highly conserved through evolution. Our results lead us to propose that Bob1-related proteins may play diverse roles in eukaryotic organisms.

Two novel flagellar components and H-NS are involved in the motor function of Escherichia coli

A mutation in H-NS results in non-flagellation of Escherichia coli due to a reduced expression of the flhDC master operon. We found that the hns-negative strain restored its flagellation in the presence of flhDC, although the resulting strain was still non-motile. Since the intracelluar levels of motor components MotA, MotB, and FliG in the Deltahns strain were unaltered, the non-motility indicates that H-NS affects flagellar function as well as biogenesis. We obtained an insertion in ycgR, a putative gene encoding a protein of 244 amino acid residues, which suppresses the motility defect of hns-deficient cells. The abnormally low swimming speed of hns mutant cells was fully restored by an insertion in ycgR, as assessed with computer-assisted motion analysis. A similar suppressor phenotype was observed with a multicopy expression of yhjH, a putative gene encoding a polypeptide of 256 amino acid residues. Since the flagella of most hns-deficient cells were not rotating, except a few with reduced speed, the suppression appears to increase the number of rotating flagella as observed with tethered bacteria. The ycgR and yhjH genes contain the consensus sequence found among the class III promoters of the flagellar regulon, and their expression monitored with a lacZ fusion requires FlhDC. These findings suggest that ycgR and yhjH, together with H-NS, are involved in the motor function and constitute new members of the flagellar regulon.

H-NS-Dependent regulation of flagellar synthesis is mediated by a LysR family protein

H-NS regulates the flagellar master operon (flhDC) and thus is necessary for flagellation of Escherichia coli. However, the molecular mechanism of its regulation has remained unknown. Genetic screening of a transposon insertion abolishing the H-NS effect revealed a previously unidentified gene, named hdfR, encoding a LysR family protein. Binding of purified HdfR to the flhDC promoter was demonstrated by a DNA mobility shift assay, indicating that HdfR is a transcriptional regulator for the flagellar master operon. Furthermore, the expression of the hdfR gene was shown to be negatively regulated by H-NS.

Optimal route of administration of mixed endothelin receptor antagonist (TAK-044) in liver transplantation

It is well known that endothelin-1(ET-1) is a factor involved in the pathogenesis of ischemia-reperfusion injury. This study was undertaken to investigate the optimal route (intravenous vs intraportal) for administering mixed endothelin receptor antagonist (TAK-044) in a liver transplantation. First, in a rat isolated liver cold-perfusion model, the pharmacodynamics of TAK-044 and endothelin-1 (ET) in the liver tissue and the systemic circulation after cold perfusion were compared in the different administration routes. Next, in a rat orthotopic transplantation model, we compared the hepatoprotective effect of TAK-044 among different administration routes. In each model, there were three groups: IV group, intravenous injection of TAK-044 (10mg/kg) immediately before cold perfusion or anhepatic phase; IP group, intraportal administration with cold perfusion solution or with reflush solution for the graft; control group, no treatment. In the cold perfusion model, liver tissue ET level increased to a similar extent after reperfusion in the three groups, and the plasma and liver tissue TAK-044 concentrations after reperfusion were highest in the IV group. However, the increase in plasma ET was also greatest, and therefore, the ratio of liver tissue to plasma TAK-044 was lower in the IV group compared with the IP group. In the transplantation model, elevation of plasma ET was significantly higher in the IV group. Leakage of serum alanine aminotransferase (ALT), sinusoidal narrowing, and cell swelling after grafting were significantly suppressed in the IP group. We conclude that intraportal administration before reperfusion offers more efficient accumulation of TAK-044 in the liver tissue, without harmful systemic elevation of ET, and achieves a hepatoprotective effect on the graft compared with intravenous administration.

Effects of depletion of neutrophils or macrophages on development of cigarette smoke-induced emphysema

The aim of this study was to ascertain the putative roles of neutrophils or macrophages in the pathogenesis of cigarette smoking-induced emphysema on the basis of effects of anti-neutrophil (anti-PMN) antibody or anti-monocyte/macrophage (anti-MoMac) antibody on the development of emphysema in cigarette smoke-exposed rats. Rats were treated with rabbit anti-PMN or anti-MoMac antibody and exposed 7 days/wk for 2 mo to cigarette smoke inhalation; rats treated with nonimmunized rabbit IgG (control antibody) and exposed to cigarette smoke or normal room air served as controls. Antibody treatments began 24 h before the start of smoke or air exposure and was continued with 1 treatment/wk. Total and differential cell counts in bronchoalveolar lavage fluid and collagenase-dissociated lung and determinations of the elastinolytic activity of lung neutrophils or macrophages in [(3)H]elastin-coated wells indicated specific suppression of neutrophil accumulation and neutrophil-related elastinolytic burden in the lungs of the anti-PMN antibody-treated smoke-exposed rats, in contrast to specific suppression of macrophage accumulation and macrophage-related elastinolytic burden in the lungs of the anti-MoMac antibody-treated smoke-exposed rats. Cigarette smoke exposure-induced lung elastin breakdown (quantitated by immunologic assay of levels of elastin-derived peptides and desmosine in lavage fluid) and emphysema in the lungs (based on morphometric analysis of alveolar mean linear intercepts and alveolar tissue density in fixed lungs) were not prevented in the lungs of anti-PMN antibody-treated smoke-exposed rats but was clearly prevented in lungs of the anti-MoMac antibody-treated smoke-exposed rats. These findings implicate macrophages rather than neutrophils as the critical pathogenic factor in cigarette smoke-induced emphysema.

Time course of neutrophil and macrophage elastinolytic activities in cigarette smoke-induced emphysema

The aim of this study was to compare the time course of neutrophil and macrophage elastinolytic potentials in the lungs of rats exposed daily to cigarette smoke inhalation for 1-6 mo in relation to the onset and progression of cigarette smoke-induced emphysema. Normal room air-exposed rats served as controls. Morphometric data of lung histological sections showed evidence of emphysema lesions in the lungs of smoke-exposed rats at month 2 and continuing to month 6. Data of total and differential cell counts in bronchoalveolar lavage fluid and collagenase-dissociated lung showed an increased number of lung neutrophils at month 1 of smoke exposure, but this was reduced to control levels at months 2-6. In contrast, an increased number of lung macrophages was evident in the smoke-exposed rats at month 2 of exposure and continued to month 6. Data of the elastinolytic activities of the neutrophils and macrophages, determined in [3H]elastin-coated culture wells, showed that the elastinolytic activity of lung neutrophils in the smoke-exposed rats was similar to that of the control air-exposed rats at months 1-6 of exposure. In contrast, the elastinolytic activity of lung macrophages in the smoke-exposed rats was increased at month 2 of exposure and remained increased at month 6. Excessive in vivo lung elastin breakdown (judged by increased levels of elastin-derived peptides and desmosine in lavage fluid, determined immunologically) was observed in the smoke-exposed rats at months 2-6 of exposure. These data indicate that the time course of increased macrophage-directed elastinolytic activity in the lung, not that of neutrophils, is more closely associated with the evolution of cigarette smoke-induced emphysema.

Hepatoprotective effect of a nonselective endothelin receptor antagonist (TAK-044) in the transplanted liver

This study was designed to investigate whether or not a novel nonselective endothelin A/B (ETA/ETB) receptor antagonist (TAK-044) provides hepatoprotection during porcine liver transplantation. The grafts were stored in chilled Euro-Collins solution and recirculated following reflush with lactated Ringer's with (TAK group) or without (control group) TAK-044 (10 mg/kg). Intracellular (cytoplasma, mitochondria, and nucleus) calcium (Ca) concentrations were measured in the hepatic biopsy materials obtained serially at varying time point from donor laparotomy to recipient closure using an electron probe X-ray microanalyzer. Liver function tests also were determined. The cold and warm ischemia times of the grafts were comparable between the two groups. The peak endothelin-1 T-1) concentration after recirculation was significantly higher in the TAK group than in the control group (129 +/- 30 pg/ml vs 26 +/- 6.5 pg/ml). However, release of liver enzymes, increases in total bile acid, and deterioration of indocyanine green retention rate were significantly suppressed in the TAK group. In the control group, the intracellular Ca concentrations, especially in the mitochondrial fraction, were elevated markedly following recirculation of the hepatic arterial flow. In the TAK group, this effect was suppressed. Thus, the supplementary use of the nonselective ETA/ETB receptor antagonist TAK-044 via a rinse route may alleviate an early postreperfusion microcirculatory disturbance of the liver grafts without adverse effects by the increased ET-1 on the systemic circulation.

Simultaneous quantification of insecticides including carbaryl in drinking water by gas chromatography using dual electron-capture and nitrogen-phosphorus detection

A rapid and simple gas chromatographic method for the simultaneous determination of malathion, parathion, fenitrothion, diazinon and carbaryl in drinking water is presented. A fused-silica SE-54 column was used for the separation of the insecticides and was split into two specific detectors; electron-capture and nitrogen-phosphorus detectors by using column switching. A water sample was extracted with methylene chloride. The organic phase was evaporated and the residue was derivatized with pentafluoropropionic acid anhydride. The detection limit was below 0.1 ng/ml and the calibration curves showed good linearity with r = 0.998 approximately 1.000. The method was sensitive, reproducible and simple enough to permit the reliable routine analysis of the pesticides in drinking water.

Current sensing using bismuth rare-earth iron garnet films

Ferrimagnetic iron garnet films are investigated as current-sensing elements. The Faraday effect within the films permits measurement of the magnetic field or current by a simple polarimetric technique. Polarized diffraction patterns from the films have been observed that arise from the presence of magnetic domains in the films. A physical model for the diffraction is discussed, and results from a mathematical analysis are in good agreement with the experimental observations. A method of current sensing that uses this polarized diffraction is demonstrated.

Ciprofloxacin-induced granulomatous interstitial nephritis and localized elastolysis

Ciprofloxacin is known to cause acute interstitial nephritis. We report the first case of ciprofloxacin-induced granulomatous interstitial nephritis and localized elastolysis. The patient presented with acute renal failure and skin lesions following a 14-day course of ciprofloxacin administered for cellulitis. The patient had symmetric, palm-sized, tender violaceous plaques on both axillae. The renal biopsy revealed granulomatous interstitial disease. A skin biopsy revealed an elastolytic process with histocytic infiltration and calcification. After discontinuing ciprofloxacin and starting a short course of steroid therapy, the skin lesion and renal function improved promptly. The nephritis relapsed after prednisone was discontinued and responded to a second course of steroid therapy. Ciprofloxacin, like penicillin, can cause granulomatous interstitial nephritis and elastolysis. A prolonged course of steroid therapy may be indicated in patients with ciprofloxacin-induced granulomatous interstitial nephritis to avoid early relapse.

[Time-related changes in the cerebral blood flow in subarachnoid hemorrhage due to ruptured cerebral aneurysm]

Cerebral blood flow (CBF) was determined by the 123I-IMP SPECT reference sample method in 39 patients with subarachnoid hemorrhage (SAH) due to ruptured cerebral aneurysm. They were examined according to the time lapse after onset, severity, CT findings, and prognosis. These 39 patients were admitted to our medical center within 36 hours after the onset, and SAH and ruptured aneurysm were diagnosed by CT scan and angiography, respectively. Patients with intraventricular hemorrhage, intracerebral hematoma, and other severe complications were excluded. The stage of SAH was divided into three, by designating the day of onset as day 0: day 0-4 as the acute stage, day 5-20 as the subacute stage, and day 21 and after that as the chronic stage. Acute stage surgery was conducted within 48 hours after the onset on principle. Hyperdynamic therapy and cisternal drainage were conducted in severe case of SAH. The prognosis was evaluated with Glasgow outcome scale (GOS). The average CBF was 33.39, 29.44, and 33.15 in the acute, subacute, and chronic stages, respectively. These are values lower than the reference sample value, 43.39 (ml/100 g/min). Only a small number of cases, however, revealed vasospasm by angiography conducted in the acute stage. There was a correlation between the CT severity in the acute stage and the decrease in CBF. In the group with low density area (LDA) on CT due to delayed cerebral ischemia in the subacute stage, the average CBF was 28.28 and 23.95 in the acute and subacute stages, respectively. These values were significantly lower than 35.97 and 32.45, respectively, in the group without LDA.(ABSTRACT TRUNCATED AT 250 WORDS)

Footwear and posture. Compensatory strategies for heel height

The belief that wearing high-heeled shoes increases lumbar lordosis is firmly ingrained in clinical folklore. Proponents of negative heel footwear argue that because high positive heels increase the lumbar lordosis, negative heels will decrease the lumbar lordosis. Quantitative documentation of the assumption regarding high heels is not to be found in the literature, although sporadic attempts to prove this assumption have been made throughout the 20th Century. Although other effects, such as decreased gait speed and step length, and increased knee flexion at heel strike have been found in more than one study, no increase in lumbar lordosis has been found. Where an actual decrease in lordosis has been found, authors tend to explain it away as inconsistent with what every clinician feels that he or she has observed. We felt it appropriate, then, to conduct both a static and a dynamic study to assess the effects of heel height on lumbar spine and lower limb joint kinematics in the sagittal plane, as well as other strategies to compensate for heel height. The results indicate that the greatest compensation is at the ankle and knee. Where a significant effect occurred in the lumbar spine (males, dynamic study), high heels decreased the lumbar lordosis, i.e., resulted in less swayback rather than more.

Sarcoma viruses carrying ras oncogenes induce differentiation-associated properties in a neuronal cell line

The growth-promoting and/or differentiation-blocking activities of Kirsten (Ki-MSV) or Harvey murine sarcoma virus (Ha-MSV) on various types of cells in vitro are well documented. Here we report an unexpected effect of these viruses on a rat phaeochromocytoma cell line, PC12. PC12 cells, which multiply indefinitely in growth medium, are known to respond to nerve growth factor (NGF) by cessation of cell division and expression of several properties resembling those of differentiated sympathetic neurones. We have found that Ki- and Ha-MSV mimic some, if not all, of the activities of NGF in PC12 cells, and there is evidence that the viral oncogenes, v-Ki-ras and v-Ha-ras, are responsible for this phenomenon. This system may be of value for studying the mechanism of action of the v-ras genes as well as the regulatory mechanism of growth and differentiation in neuronal cells.

Reducing back displacement in the powered reclining wheelchair

The powered reclining wheelchair used by quadriplegic and other severely disabled people was studied to determine how the chair could be modified so that repeated recline would not produce shear forces that tend to cause the user to be relocated in the chair, limiting independent functioning. Three modifications of the chair were studied: a freely sliding back, a commercially available powered sliding seat, and 4-bar linkage to hinge the chair back. A counterbalanced, freely sliding back was constructed for testing and was instrumented to measure displacement of the person in the chair during recline. The curves of back displacement vs angle or recline were determined for a sample or 8 quadriplegic subjects. The sliding back mechanism was determined to be impractical for incorporation into current chair designs since it required a heavy, rigid back frame. The sliding seat was found to have limited value since it only slightly decreased the back motion during recline. However, the 4-bar linkage virtually eliminated relative motion between the person's back and the chair back, providing a mechanism for potentially resolving this problem both in new recliner design and for retrofit to existing reclining wheelchairs.