Random migration of polymorphonuclear leukocytes induced by GM-CSF involving a signal transduction pathway different from that of fMLP

Granulocyte-macrophage colony-stimulating factor (GM-CSF) induced random migration of human polymorphonuclear leukocytes (PMNs) but not chemotaxis. Chemoattractants such as N-formyl-methionyl-leucyl-phenylalanine (fMLP), leukotriene B4 (LTB4), and interleukin-8 (IL-8) induced both random migration and chemotaxis. Other inflammatory cytokines, including granulocyte colony-stimulating factor (G-CSF), interleukin 1alpha (IL-1alpha), and tumor necrosis factor alpha (TNF-alpha), did not induce either movement. One-minute exposure of PMNs to GM-CSF was sufficient for the induction of random migration, whereas fMLP-induced random migration required continued presence of fMLP. Inhibitors of phosphatidylinositol 3-kinase (PI3-K), protein kinase C (PKC), and protein tyrosine kinase (PTK) had no effect on random migration induced by GM-CSF, whereas fMLP-induced movements were partially inhibited by PTK inhibitors but not by inhibitors of PI3-K inhibitors nor PKC inhibitors. Myosin light chain kinase inhibitors inhibited movements of PMNs induced by both GM-CSF and fMLP. These findings also imply that some aspects of the signal transduction pathway of GM-CSF leading to random migration is different from that of fMLP. Our findings suggest that cell movements are controlled through diverse signal transduction systems.

Ventilation abnormalities in obstructive airways disorder: detection with pulmonary dynamic densitometry by means of spiral CT versus dynamic Xe-133 SPECT

PURPOSE

To evaluate pulmonary dynamic densitometry (PDD) by means of spiral computed tomography (CT) for detection of ventilation abnormalities in obstructive airways disorders compared with dynamic xenon-133 single photon emission CT.

MATERIALS AND METHODS

Eight-second spiral CT was performed during two to three respiratory cycles in six healthy volunteers, 19 patients with airways disorder, and six patients with restrictive lung disease. The data sets were reconstructed as 36 1-second temporally overlapping images at 0.2-second intervals, and regional PDD curves were displayed. Regional ventilation was assessed by means of Xe-133 clearance time.

RESULTS

Normal lungs showed smooth, sinusoidal PDD curves with maximal amplitude in lung attenuation change (MALAC) of 54.9 HU +/- 24.5, whereas lungs with obstructive airways disorders with prolonged Xe-133 clearance showed significantly diminished MALAC (31.6 HU +/- 20.1, P < .0001), accompanied by irregularity, asynchronous phase, and deterioration of normal ventral-to-dorsal gradients in MALAC and lung attenuation. Lungs with restrictive diseases without prolonged Xe-133 clearance did not show statistically significant reduction in MALAC. In a total of 251 lung regions, regional MALAC correlated inversely with Xe-133 clearance time (r = -.842).

CONCLUSION

PDD by means of spiral CT is acceptable for the detection of ventilation abnormalities in obstructive airways disorder.

[Immunomodulatory effect of daily low-dose cisplatin treatment]

Immunomodulatory effects of daily low-dose cisplatin treatment were investigated on compromised patients with advanced or recurrent gastrointestinal cancer. One case of esophageal cancer, 7 of gastric cancer, 2 of colorectal cancer, 1 of carcinomatous peritonitis from unknown origin, and 1 of hepatocellular carcinoma, were treated by daily low-dose cisplatin combined with 5-FU or tegafur, and their ECOG Performance Status Score (PS), number of lymphocytes, and CD3 zeta chain expression of peripheral blood lymphocytes were studied to compare with the effects of treatment. Seven patients with esophageal cancer and gastric cancer showed a partial response and their PS was improved, and the number of lymphocytes and CD3 zeta chain expression of lymphocytes was increased. However, in two patients with progressive disease, a decreased number of lymphocytes and less expression of CD3 zeta chain were seen.

Contribution of the hydrophobic effect to the stability of human lysozyme: calorimetric studies and X-ray structural analyses of the nine valine to alanine mutants

To clarify the contribution of the hydrophobic effect to the conformational stability of human lysozyme, a series of Val to Ala mutants were constructed. The thermodynamic parameters for the denaturation of these nine mutant proteins were determined using differential scanning calorimetry (DSC), and the crystal structures were solved at high resolution. The denaturation Gibbs energy (delta delta G) and enthalpy (delta delta H) values of the mutant proteins ranged from +2.2 to- 6.3 kJ/mol and from +7 to -17 kJ/mol, respectively. The structural analyses showed that the mutation site and/or the residues around it in some proteins shifted toward the created cavity, and the substitutions affected not only the mutations site but also other parts far from the site, although the structural changes were not as great. Correlation between the changes in the thermodynamic parameters and the structural features of mutant proteins was examined, including the five Ile to Val mutant human lysozymes [Takano et al. (1995) J. Mol. Biol. 254, 62-76]. There was no simple general correlation between delta delta G and the changes in hydrophobic surface area exposed upon denaturation (delta delta ASAHP). We found only a new correlation between the delta delta G and delta delta ASAHP of all of the hydrophobic residues if the effect of the secondary structure propensity was taken into account.

Superselective bronchial artery embolization for hemoptysis with a coaxial microcatheter system

PURPOSE

To compare the effectiveness and safety of superselective bronchial artery embolization with that of nonsuperselective embolization in the control of hemoptysis.

MATERIALS AND METHODS

Retrospective case analysis was done for 47 patients with hemoptysis originating from a variety of causes. In 22 patients, embolization was performed superselectively using a microcatheter inserted into the bronchial artery beyond the spinal or mediastinal branches (superselective group). In the remaining 25 patients, embolization was performed at the opening of the bronchial artery with a 5-F catheter (nonsuperselective group).

RESULTS

Initial hemoptysis control rates were 96% (21 of 22) in the superselective group and 88% (22 of 25) in the nonsuperselective group. Cumulative hemoptysis control rates of the superselective and nonsuperselective groups were 80% and 67% at 6 months, 79% and 56% at 1 and 2 years, and 79% and 48% at 3 years, respectively (not significant; generalized Wilcoxon test). One major complication (spinal infarction) occurred in the nonsuperselective group.

CONCLUSIONS

Superselective embolization is safer and more effective way to control hemoptysis than the ordinary (nonsuperselective) method.

Clinical utility of a newly developed pressure swing adsorption-type oxygen concentrator with a membrane humidifier

The clinical utility of the newly developed pressure swing adsorption (PSA)-type oxygen concentrator with a membrane humidifier that does not require added water for humidification was evaluated in 13 patients with chronic pulmonary disease who were receiving long-term oxygen therapy. PaO2 and the relative humidity were measured when the patient breathed air and oxygen from the new device via a nasal cannula. After using the new concentrator for 5 h, the patients were asked whether they experienced dry nasal passages or a dry throat. A significant difference between the PaO2 measured while the patients breathed room air and while they breathed oxygen from the new device was observed. A significant difference was observed between the relative humidity of room air (44.7 +/- 18.6%) and that of the oxygen flow (72.7 +/- 14.8%) from the new device. None of the patients experienced dry nasal passages, dry throat, or any other adverse effects. Since this new PSA-type oxygen concentrator with a membrane humidifier supplies well-humidified nasal oxygen without water, laborious cleaning of the container and changing of the water are not necessary, and may help to improve the patient's quality of life.

Estrogen and parathyroid hormone regulate insulin-like growth factor binding protein-4 in SaOS-2 cells

The effect of 17beta-estradiol and parathyroid hormone (PTH) on the expression of insulin-like growth factor-binding protein-4 (IGFBP-4) messenger RNA (mRNA) was studied in the cultured human osteoblast-like SaOS-2 cells. Treatment of SaOS-2 cells with PTH for 3 h caused 3.3-fold increase in IGFBP-4 mRNA levels which was determined by reverse transcription-polymerase chain reaction. 17beta-Estradiol had no effect on either the stimulation of mRNA level by PTH or the basal level. Together with our previous report that 17beta-estradiol inhibits the PTH-induced reduction of IGFBP-4 proteolysis in these cells, the results obtained may help to explain the mechanisms of determining IGFBP-4 availability by systemic hormones in osteoblast cells.

Location and behavior of dorsal determinants during first cell cycle in Xenopus eggs

In Xenopus eggs, removal of small volumes of cytoplasm along with the surface (2-10% of the entire egg volume) causes very severe dorsal reduction (average DAI=1.4) when made at a site ventrally 30 degrees off the vegetal pole at 20% time of first cell cycle (0.2 NT). The greatest dorsal reduction (average DAI=1.1) occurs when removal is done at the vegetal pole at 0.3 NT, and intermediate reductions (average DAI=2.2-2.6) when done at sites dorsally, dorsolaterally or laterally 30 degrees off the vegetal pole at 0.4 NT. Removal at sites dorsally, dorsolaterally or laterally 60 degrees off the vegetal pole provokes slight dorsal reduction (average DAI=3.5-3.9) when made at 0.4-0.5 NT. Removal at all sites after 0.4 NT causes a steady decrease in the extent of dorsal reduction. By contrast, removal of larger volumes of dorsal cytoplasm (16-50% of the entire egg volume) causes a steady increase in the extent of dorsal reduction during first cell cycle with its maximum effect at 1.0 NT (average DAI=3.1). The surgery for the cytoplasmic removal does not affect cortical rotation. We conclude from these results that dorsal determinants are concentrated first in a small region ventrally 30 degrees off the vegetal pole by 0.2 NT, then move toward the vegetal pole during the period 0.2-0.3 NT and disperse to a broad region spanning over both the presumptive dorsal and ventral, but mainly the dorsal, hemispheres during the period 0.3-0.8 NT.

Effect of basic fibroblast growth factor on experimental focal ischemia studied by diffusion-weighted and perfusion imaging

BACKGROUND AND PURPOSE

Basic fibroblast growth factor (bFGF) has documented neuroprotective properties. This study was performed to evaluate the effects of bFGF on infarct size when administered 30 minutes after induction of focal cerebral ischemia in rats. Diffusion-weighted and perfusion MRI were used during the drug infusion.

METHODS

We blindly randomized 20 Sprague-Dawley rats to receive either drug (n = 10) or vehicle (n = 10). The animals underwent middle cerebral artery (MCA) occlusion using the suture model. Diffusion-weighted MRI was initiated 30 minutes after induction of ischemia and repeated frequently for 3.5 hours. Drug (45 micrograms/kg per hour) or vehicle (saline) infusion began 30 minutes after MCA occlusion and continued for 3 hours. Perfusion images were made at 25, 90, and 150 minutes after MCA occlusion. The animals were killed after 24 hours of permanent MCA occlusion, and brains were stained with 2,3,5-triphenyltetrazolium chloride (TTC).

RESULTS

The TTC-derived, corrected infarct volume postmortem in the bFGF-treated group was significantly smaller than that in controls (126.6 +/- 51.9 versus 180.2 +/- 54.9 mm3, mean +/- SD, P = .038). Diffusion imaging showed essentially equal lesion volumes 3 hours after MCA occlusion (195.4 +/- 61 mm3 in the drug-treated group and 194.4 +/- 65 mm3 in controls). At 4 hours, ischemic lesion size was 182.1 +/- 56.9 mm3 in treated animals and 222.9 +/- 88.7 mm3 in the controls (P = .24, NS). Perfusion imaging did not show a change of cerebral perfusion within ischemic brain regions in the bFGF group during the infusion. No behavioral or physiological side effects were observed.

CONCLUSIONS

bFGF is a safe and effective treatment for focal cerebral ischemia in rats. We observed a modest delayed difference of ischemic lesion size in vivo with diffusion MRI. The diffusion-weighted MRI findings suggest a potential delayed therapeutic effect of bFGF, and the perfusion imaging findings imply that the effect is not due to increased blood flow to the ischemic region.

The structure, stability, and folding process of amyloidogenic mutant human lysozyme

The physicochemical properties of an amyloidogenic mutant human lysozyme (Ile56Thr) were examined in order to elucidate the mechanism of amyloid formation. The crystal structure of the mutant protein was the same as the wild-type structure, except that the hydroxyl group of the introduced Thr56 formed a hydrogen bond with a water molecule in the interior of the protein. The other physicochemical properties of the mutant protein in the native state were not different from those of the wild-type protein. However, the equilibrium and kinetic stabilities of the mutant protein were remarkably decreased due to the introduction of a polar residue (Thr) in the interior of the molecule. It can be concluded that the amyloid formation of the mutant human lysozyme is due to a tendency to favor (partly or/and completely) denatured structures.

Enhancement of Ca2+ currents by GHRH and its relation to PKA and [Ca2+]i in human GH-secreting adenoma cells

The effects of human growth hormone-releasing hormone (hGHRH) on Ca2+ channels were examined in human growth hormone-producing adenoma cells using the perforated whole cell clamp technique. These cells exhibited T- and L-type Ca2+ channel currents, and application of 10(-8) M hGHRH increased the amplitude of both currents. Application of 10(-5) M 8-bromoadenosine 3',5'-cyclic monophosphate also increased T- and L-type currents. Additional application of 10(-8) M hGHRH did not further increase the current amplitudes. Treatment with the Rp diastereomer of adenosine 3',5'-cyclic monophosphothioate (10(-5) M) or H-89 (10(-5) M) inhibited the enhancement of Ca2+ channel currents by hGHRH, as did intracellular injection of protein kinase A (PKA) inhibitor peptide [PKI-(5-24)], indicating that hGHRH increased the amplitude of Ca2+ channel currents through the activation of the adenosine 3',5'-cyclic monophosphate (cAMP)-PKA system. When intracellular Ca2+ concentration ([Ca2+]i) was chelated to < 30 nM with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid acetoxymethyl ester (BAPTAAM), hGHRH failed to increase the Ca2+ channel currents. In this condition, hGHRH activated nonselective cation channels, which revealed that the cAMP-PKA system operated after treatment with BAPTA-AM and that the site of low [Ca2+]i-induced inhibition of hGHRH effects on Ca2+ channels was at a step after PKA activation.

Corticotropin-releasing hormone excites adrenocorticotropin-secreting human pituitary adenoma cells by activating a nonselective cation current

The mechanisms of corticotropin-releasing hormone (CRH) induced excitation of ACTH-secreting adenoma cells were investigated using the perforated whole-cell clamp technique and intracellular Ca2+ concentration ([Ca2+]i) measurement. CRH depolarized ACTH-secreting adenoma cells by activating a nonselective cation current that showed slight inward rectification. This channel did not seem to be a member of the Ca(2+)-activated cation currents because it was activated even when the [Ca2+]i was chelated below 50 nM. The activation of the current was induced by protein kinase A-mediated pathways. By [Ca2+]i measurement, CRH increased [Ca2+]i of these cells dependently on voltage-gated Ca2+ current. This CRH-induced [Ca2+]i increase was abolished in Na(+)-free extracellular solution, but was not abolished by the addition of 5 microM tetrodotoxin to the extracellular solution. CRH-induced ACTH secretion from the cultured adenoma cells was also abolished in Na(+)-free extracellular solution, but not in tetrodotoxin-containing extracellular solution. These data indicate that a Na+ current (maybe the nonselective cation current) other than voltage-gated Na+ current plays an important role in CRH-induced [Ca2+]i increase and ACTH secretion. CRH also activated a nonselective cation current in nonadenoma human corticotrophs, suggesting that the activation of a nonselective cation current is a physiological mechanism of CRH-induced excitation in human corticotrophs.

Growth response to growth hormone therapy in patients with different degrees of growth hormone deficiency

Growth response to GH therapy in prepubertal patients with idiopathic GH deficiency (GHD) was analyzed in terms of the chronological age at the start of GH treatment and the GH secretory capacity, by using the large database provided by the International Cooperative Growth Study (ICGS) Japan. 1192 patients, aged from 3 to 10 years were divided into three groups with the following maximum GH values in GH stimulation tests: Group A: both < or = 5 ng/ml, group B: both 5-10 ng/ml, group C: one > 10 ng/ml. Analysis of age-related growth response using with delta height SDS (delta height SDS) as a response variable revealed that the group A patients responded better to GH, while there was no differences between the other groups. Simple and multiple regression analysis showed that IGF-I and chronological age (CA) negatively correlated with growth response, and target height SDS-height SDS positively correlated. These three most important predictors accounted for 49% of the variation in the growth response in group A, whereas six variables such as CA, frequency of GH injection, % overweight, GH dose, target height-height SDS, and pretreatment height velocity SDS accounted for only 28% of those in groups of B and C. These results lead us to conclude that growth response to GH is related to the degree of GH impairment with its cut-off level of 5 ng/ml. From these findings it might be suggested that treatment regimen should be tailored to individual requirements according to the degree of GHD.

Gq/11 and PLC-beta 1 mediate the substance P-induced inhibition of an inward rectifier K+ channel in brain neurons

1. Substance P (SP) induces a slow neuronal excitation in cholinergic neurons from the nucleus basalis by suppressing an inwardly rectifying K+ current (Kir). We have determined which G protein alpha-subunit mediates this SP effect. 2. After intracellularly injecting antibody against each alpha-subunit of G proteins (Gq alpha/11 alpha, G12 alpha, and G13 alpha) with an Eppendorf microinjector, we examined, by using the whole cell patch-clamp and the ON-cell mode of single-channel recording, the effect of SP on Kir in cultured neurons of the nucleus basalis. The effect of SP on Kir was substantially reduced in neurons injected with antibodies to Gq alpha/11 alpha but not with antibodies to G12 alpha or G13 alpha. 3. The effects of antibodies against three isozymes of phospholipase C (PLC-beta 1, PLC-beta 2, and PLC-beta 3) were tested. The SP-induced suppression of Kir was reduced by antibody against PLC-beta 1 but not by antibodies against PLC-beta 2 or PLC-beta 3. 4. We conclude that the SP-induced inhibition of Kir in nucleus basalis neurons is mediated by Gq/11 and PLC-beta 1.

Superimposition of In-111 platelet SPECT and CT/MR imaging in intracardiac thrombus

An initial attempt to superimpose in-111-labeled platelet SPECT over CT/MRI in two patients with intracardiac thrombus is presented. One patient was a 65-year-old woman with a history of mitral and tricuspid valve replacement. This patient had a large thrombus measuring 74 x 43 x 34 mm in the right atrium. Fusion imaging with CT showed increased in-111 activity on the surface of the thrombus, which was visualized as circular activity on a planar image. The other patient was a 72-year-old woman who had a thrombus measuring 17 x 14 x 12 mm at the cardiac apex. Planar imaging showed two discrete areas of abnormal in-111 activity. Superimposition of the SPECT image over MR revealed that one of these areas corresponded to the small thrombus, whereas the other related to a previous subendomyocardial biopsy. In both patients, the activity ratio of the abnormal in-111 accumulation versus the cardiac chamber on SPECT was greater than that on planar images. The correlation of in-111 platelet SPECT and CT/MRI was useful in accurately localizing the intracardiac thrombus.

Secretory granule formation and synthesis pathway of secretory proteins in parotid gland cells

The cytochemical technique for endogenous peroxidase and an immunocytochemical method with protein A-gold were used to investigate the formation of the secretory granule substructure in acinar cells of the gerbil parotid glands in normal conditions and after treatment with the ionophore monensin. In untreated animals and 90 min after treatment with monensin, peroxidase activity was seen in rER, in transport vesicles close to the condensing vacuoles, and in the dense core of condensing vacuoles and secretory granules, whereas the Golgi cisternae remain unreactive. At 45 or 60 min after stimulation with monensin, the condensing vacuoles and the immature granules in the trans Golgi area did not exhibit dense cores and their content appeared similar to the peripheral portion of the mature secretory granules. These observations suggest that, in Mongolian gerbil parotid acinar cells, some substances such as peroxidase may be transported from the rER directly to the condensing vacuoles.

Proadrenomedullin NH2-terminal 20 peptide inhibits the voltage-gated Ca2+ channel current through a pertussis toxin-sensitive G protein in rat pheochromocytoma-derived PC 12 cells

The effect of proadrenomedullin NH2-terminal 20 peptide (PAMP) on the voltage-gated Ca2+ channel current was investigated using the perforated whole-cell clamp technique on NGF-treated PC12 cells. PAMP inhibited the Ba2+ current through N-type Ca2+ channels in a concentration dependent manner. Injection of GDPbetaS into the cell abolished the inhibition while injection of GTPgammaS into the cell made the inhibition irreversible, indicating that the PAMP-induced inhibition of the voltage-gated Ca2+ channel was mediated by a G protein. The inhibition was abolished by pretreating the cells with pertussis toxin, indicating that a pertussis toxin-sensitive G protein was involved in the signal transduction mechanism of PAMP. The present study revealed that the inhibition of catecholamine secretion from sympathetic nerve endings by PAMP could be explained by the inhibition of N-type Ca2+ channels, which was mediated by pertussis toxin-sensitive G protein.