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Key Points: • A pronounced low velocity anomaly (>15%) beneath the Tatun volcano group is found at the depths of 5-25 km as the magma reservoir. • A high melt fraction of ~16% for the magma reservo...

To investigate the role of alveolar macrophages in airway remodeling in asthma.Sixteen Wistar rats were divided into two groups: control group and asthmatic group. The expressions of platelet-derived growth factor-b (PDGF-b) and transforming growth factor-beta. (TGF-beta 1) in the alveolar macrophages of allergic rats were detected by immunohistochemistry and in situ hybridization.The expression of TGF-beta 1 in alveolar macrophages in allergic group was increased in both protein level (P0.05) and TGF-beta 1 mRNA(P0.01); but the expression of PDGF-b had no difference between the two groups.The alveolar macrophages may involve in the airway remodeling of asthma.

Human lung squamous carcinoma cell line(TUL cell) was treated with 5 x 10(-6) mol.L-1 all-trans retinoic acid(ATRA). Cell numbers were estimated by 0.4% trypon blue stain. MTT test was used for determining the percentage of cell growth inhibition(GI). DNA syntheses of cells were evaluated by 3H-thymidine incorporation. Cell ultrastructure was examined by transmission electron microscope(TEM). TUL cells were treated with or without ATRA, and transplanted in cutaneous of Balb/c nude mice. The results showed that: 1. The speed of cell growth in study group was smaller than that in control group. 2. The GI of cell lines TUL was 42.3%. 3. The percentage of 3H-thymidine incorporation of TUL cells was declined significantly. 4. Ultrastructure under TME showed that TUL cells treated with ATRA was suppressed. These results suggest that ATRA has the effects on growth-inhibition and differentiation-induction of TUL cell.

To evaluate the relationship between FHIT gene and gastrointestinal cancers.Matched normal and cancerous tissues from 26 patients with primary gastric carcinoma and 30 patients with colorectal carcinoma were analysed by nested polymerase chain reaction(RT-PCR) and direct sequencing of the products.Seven of 26(26.9%) gastric cancer tissues and eight of 30(26.7%) colorectal cancer tissues expressed aberrant FHIT transcripts, but no aberrant FHIT transcript was observed in all the matched normal tissues. Sequence analysis of the aberrant transcripts of 2 gastric cancer tissues(G8T, G25T) and 2 colorectal cancer tissues(C5T, C26T) confirmed the absence of 1 to 3 exons of FHIT gene.The expression of aberrant FHIT transcripts is common and tumor-specific in gastrointestinal cancers and abnormalities of FHIT gene may be associated with gastrointestinal tumorigenesis.

To explore the expression of interleukin-5(IL-5) and interleukin-10(IL-10) and their relationship in asthma, we measured the cells in bronchial alveolar lavage fluid(BALF) of guinea pigs, and examined the expression of IL-5 mRNA and IL-10 mRNA of bronchial tissue by reverse transcription polymerase chain reaction(RT-PCR) in control group(Group C, n = 10), asthmatic group(Group A, n = 11) and dexamethasone treatment group(Group B, n = 10). The results showed that the eosinophil(EOS) percentage and the expression of IL-5 mRNA were significantly higher in Group A[(48.64 +/- 17.8)%, (106.91 +/- 20.09)% respectively] than that in Group C[(15.10 +/- 11.48)%, (62.60 +/- 13.84)%] and Group B[(28.4 +/- 10.32)%, (75.30 +/- 10.70)%]. In contrast, the IL-10 mRNA expression in Group A[(47.5 +/- 5.3)%] was obviously lower compared with that in Group C[(101.2 +/- 4.2)%] and Group B[(80.1 +/- 8.3)%]. The correlation between the expression level of IL-5 mRNA and percentage of EOS was positive(r = 0.924, P0.01), whereas the IL-5 mRNA was negatively correlated with IL-10 mRNA expression(r = -0.731, P0.01).IL-5 and EOS might play a role in the pathogenesis of asthma, the inhibition of IL-10 mRNA expression may cause the increase of IL-5 expression in asthma. The beneficial effects of corticosteroid treatment in asthma may partly result from increasing IL-10 mRNA expression and inhibiting IL-5 mRNA expression.

The etiologic agents in 200 patients with pneumonia were studied by the bacterial culture of sputums obtained from the protected single catheter brush or quantitative expectoration at one morning or three-morning expectoration. Two hundred patients were divided into 3 groups. Group 1 was Nosocomial pneumonia (NP patients). Group 2-1 and Group 2-2 were community acquired pneumonia (CAP patients). All cases in Group 1 and Group 2-2 suffered from significant underlying diseases while Group 2-1 did not. Gram-negative bacilli(GNB) were isolated from the specimens in Group 1 (87%) and Group 2-2 (75%), respectively. Pseudomonas (30.8%) and klebsiella (20.5%) were the predominant bacteria (in Group 1 and pseudomonas bacteria) in Group 1 and pseudomonas (27.3%), acinetobacter (23%) and kledsiella (18%) were the major etiologic agents in Group 2-2. The commonest pathogens in Group 2-1 were gram-positive cocci (75%), in which streptococcus (38%) and staphylococcus aureus (25%) were the dominant agents. Compared with Group 2, Group 1 suffered from more mixed bacteria and the agents presented severer drug-resistant. The prognosis was worse in Group 2-2 than in Group 2-1. The results showed that the GNB pneumonia was more common in the cases who had underlying disease, no matter whether the pneumonia was NP or CAP. These patients had more trouble on their antibiotic therapy. Thus it is important that doctors should use vigorous antibiotics timely while treating these patients' underying diseases.

Measurements of lateral molecular diffusion on blebs formed on the surfaces of isolated muscle cells and myoblasts are reported. These blebbed membranes retain integral proteins but apparently separate from the detectable cytoskeleton. On blebs, acetylcholine receptors, concanavalin A receptors, and stearoyldextran extrinsic model receptor molecules are free to diffuse with a diffusion coefficient (D) approximately 3 x 10(-9) cm2/s, which is close to the value predicted for hydrodynamic drag in the lipid membrane. In contrast, diffusion of these typical receptors in intact cell membranes is constrained to D approximately less than 10(-10) cm2/s with substantial fractions virtually nondiffusible (D less than 10(-12) cm2/s). Lipid analog diffusion is also slightly enhanced in blebs as expected of evanescent lipid protein interaction. This strong enhancement of membrane protein diffusion is attributed to release from unidentified natural constraints that is induced in some way by detachment of the bleb membrane.

The method of double‐exposure speckle photography (DESP) has been illustrated in experiments to determine the small displacements of a solid object. The object was illuminated by laser light and the speckle pattern was photographed on a stationary photographic film twice, once before and once after the object was displaced. The doubly exposed film, after being photographically processed, was illuminated by laser light to produce equally spaced Young’s interference fringes on the Fraunhofer diffraction plane. From the spacing and the orientation of these fringes, both the magnitude and the direction of the displacement were determined. We have used the DESP method to measure the small length change of a cadmium tube due to thermal expansion and determined the linear thermal expansion coefficient of cadmium.

Measurements of the reflectivity of the liquid-gas interface in SF6 near its critical temperature Tc have given values of the effective interface thickness L' = (1.60 f 0.07) EO.~~~*OJJ~~A where E = 1 - T/Tc. Preliminary analysis of measurements of the correlation function of the hete- rodyne spectrum of the quasi-elastic light scattering by thermal excitations of the interface yielded -0 06 the surface tension a = 39.6 2;:: e1'34+0:03 ergjcmz in the range 4 x 10-4 4 e < 4 x 10-2 and - 7- the average viscosity q = 287 + 13 (Tc - T) rt 20 x 10-6 poise. The theory of Fisk and Widom is tested and the Kawasaki form of the thermal diffusivity A = k~ T/6 ni75 is computed and compared with the measurements of the spectral width of Rayleigh scattering.

The fluorescence recovery kinetics of succinyl-fluorescein Concanavalin A (S-F-ConA) in glycerol-physiological saline solutions of high viscosity and when bound to the surface of mouse fibroblasts were measured following brief photobleaching using a laser excited fluorescence microscope. In the high viscosity solutions, the recovery kinetics, interpreted on the basis of a simple diffusion model, yielded a diffusion coefficient in close agreement with the values predicted by the Stokes-Einstein equation. Recovery kinetics for S-F-ConA bound to the surface of mouse 3T3 and SV3T3 cells cultured in vitro yielded diffusion coefficients in the range of 5-10-10(-11) cm2/s, values considerably lower than those reported previously for membrane proteins. These measurements indicated that a considerable fraction of the S-F-ConA molecules bound to the cell surface are immobilized. These results are discussed in relation to current concepts of lateral motion of protein components within natural membranes.

Flavodilol, ((+/-)-7-[2-hydroxy-3-(propylamine)-propoxy]flavone maleate), a new orally effective antihypertensive agent, extensively depleted catecholamines and serotonin in heart tissue of normotensive and spontaneously hypertensive rats (SHR). Dose-response studies demonstrated that greater than or equal to 75% depletion of cardiac norepinephrine (NE) was accompanied by marked blood pressure decline in SHR. In contrast, whole brain biogenic amine levels were decreased only by 15-20% after acute or chronic treatment with antihypertensive doses (35-75 mg/kg). Adrenal epinephrine (EPI) stores were unaffected by acute treatment, although chronic treatment for 18 days with an antihypertensive dose of 75 mg/kg flavodilol decreased EPI by 70%. Acute treatment also decreased serotonin content of spleen by 70-80%. In dogs, a cumulative oral dose of 40 mg/kg decreased catecholamines by greater than or equal to 50% in aorta and heart muscle. Although hypothalamic catecholamine stores appeared to be more susceptible to depletion by flavodilol than catecholamines in other brain regions, these changes did not appear functionally related to blood pressure decreases since analogs of flavodilol without antihypertensive properties produced equivalent or greater depletion of hypothalamic catecholamine stores. In vitro flavodilol promoted spontaneous and potassium-evoked release of dopamine from isolated striatal nerve endings (0.3 microM) and blocked uptake of NE by hypothalamus and hippocampal nerve endings (1 microM), suggesting that biogenic amine depletion in vivo may be caused by an interference with storage and release mechanisms. Despite structural features reminiscent of beta-adrenergic antagonists, flavodilol had low affinity for beta-receptors. Neither was there any inhibition of tyrosine hydroxylase. These findings suggest that the antihypertensive activity of flavodilol results, at least in part, from depletion of sympathetic stores of NE in heart and vascular tissues that moderate adrenergic transmission, thereby decreasing heart rate (HR) and prevailing vascular tone.

Flavodilol, a new antihypertensive drug, was evaluated in a variety of test systems for better understanding of its biologic properties and the nature of its mechanism of action. Oral administration of the drug to spontaneously hypertensive rats (SHR) lowered arterial blood pressure (ABP) in a dose-related manner, and doses greater than 35 mg/kg increased duration but not magnitude of the response. In contrast, oral administration of flavodilol to normotensive rats did not significantly alter ABP at 35 mg/kg, although larger doses of 75 or 150 mg/kg significantly lowered ABP. In rats with DOCA/salt hypertension, flavodilol effectively lowered ABP to a degree similar to that observed in SHR. At antihypertensive doses, flavodilol did not alter blood pressure responses to a 90 degrees head-up tilt in SHR and did not influence cardiac output in conscious SHR. In addition, flavodilol did not appear to manifest its antihypertensive activity through an interaction with beta-adrenoceptors, dopamine (DA) receptors or prostaglandin synthetase. Daily oral administration of flavodilol to SHR for 4 days resulted in augmented vasopressor responses to exogenously administered epinephrine (EPI) or norepinephrine (NE) and attenuated responses to exogenously administered tyramine. In addition, flavodilol treatment attenuated in a dose-related manner ABP and heart rate (HR) responses of pithed SHR to electrical stimulation of sympathetic nerves. We conclude that flavodilol is an effective antihypertensive drug which decreases the release of NE from postganglionic sympathetic nerves, resulting in attenuation of peripheral noradrenergic function.

The use of fluorescence recovery after photobleaching (FRAP) techniques to monitor the lateral mobility of plant lectin-receptor complexes on the surface of single, living mammalian cells is described in detail. FRAP measurements indicate that over 75% of the wheat germ agglutinin receptor (WGA-receptor) complexes on the surface of human embryo fibroblasts are mobile. These WGS-receptor complexes diffuse laterally (as opposed to flow) on the cell surface with a diffusion coefficient in the range of 2 X 10(-11) to 2 X 10(-10) cm2/sec. Both the percentage of mobile WGA-receptor complexes and the mean diffusion coefficient of these complexes are higher than that obtained from earlier FRAP measurements of the mobility of concanavalin A-receptor (Con A-receptor) complexes in a variety of cell types. The possible reasons for the differing mobilities of WGA and Con A receptors are discussed.

Many measurements of lateral diffusion of proteins and lipids on cell membranes and lipid model membranes have become available through application of fluorescence photobleaching recovery methods. A puzzling aspect of these results is slow diffusion and partial immobilization of protein molecules on the cell surface. Observed protein diffusion coefficients on vertebrate structural tissue cells are consistently D less than or equal to 10(-10) cm2/s, while lipid analogues diffuse with D approx. 10(-8) cm2/s. Substantial fractions of the cell membrane proteins are not diffusible. In a pure viscous membrane, theoretical fluid dynamics has suggested only small differences between lipid and protein diffusion coefficients. Measurements of protein diffusion in model membranes recently showed D less than or equal to 10(-9) cm2/s, as expected. Recent experiments on cell membranes show that uncoupling of the membrane from the cytoskeleton by formation of blebs releases the membrane protein molecules so that diffusion is enhanced to D greater than or equal to 10(-9) cm2/s and the non-diffusible fraction is eliminated.