[Long-term follow-up study of postoperative revascularization in childhood moyamoya disease: results of 226 cases]

OBJECTIVE

To study the long-term results of 226 patients with moyamoya disease ased below 15 years and to report the modified method of extra-intracranial arterial anastomosis and encephalo-myo-arterio-syn-anastomosis, etc.

METHOD

The mean follow-up period was 15.5 years (range 8 - 19 years). The results were obtained from the pre- and postoperative cerebral angiographic examination, MRI, CT, cerebrovascular Doppler ultrasonography, Glasgow Outcome Scale (GOS), intelligence quotient (IQ) as classified by Taft and neurological symptoms.

RESULT

Of the 226 patients with childhood moyamoya disease, 64 (28%) recovered in completely, 69 (31%) in improved markedly, and 46 (20%) improved slightly. 43 patients (19%) had no changes and 4 (2%) died. The effective rate of the operation was 79%.

CONCLUSION

The modified direct anastomosis and encephalo-myo-arterio-synagiosis played a role in this improvement by increasing CBF after the operation. A significant correlation is found between the postoperative effect and the stages of preoperative angiograms.

[Clinical observation on artificial shexiang baoxin pill in treating 112 patients of coronary heart disease with angina pectoris]

OBJECTIVE

To test and verify the effect of artificial Shexiang Baoxin Pill (SXBXP, a heart protecting musk pill).

METHODS

Two hundred and twenty-five patients of coronary heart disease (CHD) with angina pectoris were randomly and blindly assigned to the study group (112 cases) and the control group (113 cases). The two groups were well matched in age, sex, angina type, complication and grade of cardiac function. Two pills of artificial or natural SXBXP were given to each cases of the two groups for 3 times every day orally, for 2 weeks, respectively.

RESULTS

Both the artificial and natural SXBXP could not only reduce significantly the frequency of angina episode and the daily consumption of nitroglycerin, they also could result in remarkable improvement of NST, sigma ST and exercise tolerance, as well as significant reduction of rate-pressure product. The total symptomatic effective rate of the two groups was 86.6% and 89.4% respectively, and the ECG effective rate, 52.7% and 57.5% respectively (P > 0.05), and the incidence of headache of the two groups was one for eoch. In addition, the onset of action of both agents was rapid, 88.5% of the study group and 78.6% of the control group were within five minutes. The sustained time of action of the two groups was also similar, i.e. 4.9 +/- 4.4 h vs 5.4 +/- 3.1 h.

CONCLUSION

The clinical efficacy and side effect of artificial SXBXP were very similar to those of natural SXBXP.

Molecular modeling of cytochrome P450 2B1: mode of membrane insertion and substrate specificity

A molecular model of a mammalian membrane-bound cytochrome P450, rat P450 2B1, was constructed in order to elucidate its mode of attachment to the endoplasmic reticulum and the structural basis of substrate specificity. The model was primarily derived from the structure of P450BM-3, which as a class II P450 is the most functionally similar P450 of known structure. However, model development was also guided by the conserved core regions of P450cam and P450terp. To optimally align the P450 2B1 and P450BM-3 sequences, multiple alignment was performed using sequences of five P450s in the II family, followed by minor adjustments on the basis of secondary structure predictions. The resulting P450 2B1 homology model structure was refined by molecular dynamics heating, equilibration, simulation, and energy minimization. The model suggests that the F-G loop serves as both a hydrophobic membrane anchor and entrance channel for hydrophobic substrates from the membrane to the P450 active site. To assess the mode of substrate binding, benzphetamine, testosterone, and benzo[a]pyrene were docked into the active site. The hydrophobic substrate-binding pocket is consistent with the preferences of this P450 toward hydrophobic substrates, while the presence of an acidic Glu-105 in this pocket is consistent with the preference of this P450 for the cationic substrate benzphetamine. This model is thus consistent with several known experimental properties of this P450, such as membrane attachment and substrate selectivity.

Interleukin-1 receptor antagonist suppresses Langerhans cell activity and promotes ocular immune privilege

PURPOSE

To determine whether the capacity of Langerhans cells (LCs) to abrogate ocular immune privilege can be suppressed by the topical application of interleukin-1 receptor antagonist (IL-1ra).

METHODS

Cautery was applied to corneas of BALB/c mice on day 0 to induce centripetal migration of LCs. Immune privilege was tested by the ability to induce anterior chamber-associated immune deviation (ACAID) to intracamerally injected soluble antigen 1 to 2 weeks after cautery application. The number of LCs was enumerated by immunofluorescent staining. In other experiments, freshly procured Thy-1-depleted epidermal cells, with or without LC depletion, were injected directly into virgin murine corneas before testing for ACAID. All test animals were randomized for treatment with either topical IL-1ra or placebo in a masked fashion for 1 to 2 weeks after induction of LC migration and before intracameral injection of antigen.

RESULTS

Intracorneal injection of freshly procured LC-depleted epidermal cells into normal eyes failed to abrogate ACAID, whereas LC-containing cell populations uniformly led to loss of immune privilege (P < 0.01). Topical treatment with IL-1ra led to retention of the cauterized eyes' capacity for ACAID induction (P < 0.01) and to a profound (>80%) suppression of LC migration compared with untreated controls (P < 0.01). Additionally, topical IL-1ra treatment of eyes with intracorneally injected LCs preserved immune privilege and ACAID induction (P < 0.001).

CONCLUSIONS

IL-1 mediates mechanisms of immunity in corneal inflammation that subvert the normal eye's immune privileged state. However, its antagonism with topical administration of IL-1ra preserves ocular immune privilege and ACAID through suppression of LC function.

Naïve, hapten-specific human T lymphocytes are primed in vitro with derivatized blood mononuclear cells

Our goal is to develop an in vitro system for priming naïve, hapten-specific human T cells similar to the effector cells that mediate contact hypersensitivity in vivo. Using strategies based on results of experiments conducted with murine cells, we stimulated peripheral blood T cells from normal human beings in vitro with peripheral blood mononuclear cells that had been pretreated with granulocyte-macrophage colony stimulating factor and then derivatized with dinitrochlorobenzene. T cells activated in this manner in vitro were compared functionally with immune T cells from individuals sensitized to dinitrochlorobenzene. We found that dinitrochlorobenzene-derivatized fresh peripheral blood mononuclear cells induced significant proliferation among immune T cells. Large amounts of interferon-gamma, but no interleukin-4, were detected in supernatant of these cultures. More interestingly, a significant number of T cells were activated when nave, hapten-specific T cells were stimulated with dinitrochlorobenzene-modified, cultured autologous peripheral blood mononuclear cells. Again, copious amounts of interferon-gamma were detected in the culture supernatants. Furthermore, this subset of T cells proliferated and secreted interferon-gamma, but not interleukin-4, when restimulated in vitro with dinitrochlorobenzene-derivatized fresh peripheral blood mononuclear cells. In these regards, in vitro activated T cells functionally resembled T cells that were harvested from the blood of individuals previously sensitized with dinitrochlorobenzene. This in vitro system for activation of naive, hapten-specific T cells offers opportunities on the one hand to study the earliest T cell and antigen-presenting cell events in the induction of human contact hypersensitivity, and on the other hand to simulate in vitro therapies with molecules designed to abort or prevent contact hypersensitivity when it causes disease.

[Study on the enantiomeric separation of adrenalines by capillary zone electrophoresis]

Capillary zone electrophoresis (CZE) has been used for the enantiomeric separation of the racemic isoprenaline, noradrenaline and adrenaline with bare fused silica capillary and employing beta-cyclodextrin(beta-CD) and beta-cyclodextrin derivatives as the chiral selectors. Both the complexion and enantiomeric resolution were influenced by the temperature, beta-CD type, CD concentration and pH of background electrolyte (BGE). The effects of the BGE types and concentrations on the enantiomeric separation were also investigated. The results showed that 2,6-di-O-carboxymethyl-beta-cyclodextrin (CM-beta-CD) has stronger recognition than that of beta-CD for the chiral separation of the basic drugs under study. The CD concentrations and pH of BGE have strong influence on the efficiency of chiral separation. The adsorption of the basic compound on the surface of bare fused silica capillary is a disadvantage to the chiral separation while the use of beta-CD as the chiral selector and the addition of an amphiphile, such as tetraethylammonium bromide (TEA+) or tetrabutylammonium bromide (TBA+) to the BGE could improve the resolution of the enantiomers due to the reduction of the adsorption of the basic compound on the silica surface by the strong electrostatic force between the positively charged amphiphile and the silica surface. It was also found that as CM-beta-CD was used as the chiral selector there was no influence on the chiral separation of the basic compound whether the amphiphile was added to BGE or not. Lower temperature was favorable to improve the efficiency of the chiral separation. CM-beta-CD gave a baseline enantiomeric separation for isoprenaline, while beta-CD, under the same experimental conditions, gave an incomplete chiral separation. Both CM-beta-CD and beta-CD could not give enantiomeric resolution for noradrenaline and adrenaline.

[A preliminary study on extracellular polysaccharide isolated from fermented Tremella aurantia Schw. ex Fr]

TaA, the extracellular polysaccharide purified from the filtrate of fermented Tremella aurantia, is a water-soluble neutral polysaccharide. Gas chromatography of its alditol acetates has shown that TaA is composed of mannose and xylose by the ratio of 2.85:1. The physical and chemical properties of TaA have been characterized.

A comparison of 99mTc-MIBI myocardial SPET with electron beam computed tomography in the assessment of coronary artery disease

We compared technetium-99m methoxyisobutylisonitrile (MIBI) myocardial perfusion single-photon emission tomography (SPET) (MPS) and electron beam computed tomography (EBCT) in order to assess their respective value in the detection of coronary artery disease (CAD). 99mTc-MIBI SPET (stress-resting) and EBCT studies were performed in 51 patients with suspected CAD who underwent coronary angiography (CAG). CAG showed that of the 51 patients, 36 had coronary stenosis >/=50% while 15 had normal results. A moderate positive rank correlation was found between coronary calcification detected by EBCT and MPS score (rs=0.5283, P<0.01). The concordance between EBCT and MPS for the evaluation of CAD was 72.5% (37/51). The sensitivity of EBCT in detecting CAD in 51 patients was comparable to that of MPS (81% vs 94%, NS). However, the accuracy of EBCT was lower than that of MPS (78% vs 94%, P<0.025). As regards the detection of individual coronary artery disease, there was no significant difference in sensitivity between EBCT and MPS (65% vs 75%, NS); however, the specificity and accuracy of EBCT were lower than those of MPS (specificity: 77% vs 95%, P<0.005; accuracy 71% vs 85%, P<0.005). The sensitivity, specificity and accuracy of MPS in detecting single-vessel disease were higher than those of EBCT (sensitivity: 86% vs 42%, P<0.025; specificity: 96% vs 70%, P<0.025; accuracy: 93% vs 61%, P<0.005). However, no significant differences in the sensitivity, specificity and accuracy of MPS and EBCT were found in respect of multivessel disease.

IN CONCLUSION

99mTc-MIBI myocardial perfusion SPET and EBCT provide different information in the assessment of CAD. The sensitivity of EBCT for the detection of CAD is comparable with that of MPS; however, the specificity and accuracy of EBCT are lower than those of MPS. More reliable results will be obtained if both myocardial perfusion SPET and EBCT are performed.

Ultraviolet B-exposed and soluble factor-pre-incubated epidermal Langerhans cells fail to induce contact hypersensitivity and promote DNP-specific tolerance

Acute low-dose ultraviolet B (UVB) radiation impairs the induction of contact hypersensitivity (CH) and induces tolerance in UVB-susceptible strains of mice when dinitrofluorobenzene (DNFB) is applied to an irradiated skin surface. We are interested in learning the cellular and molecular bases for the existence of UVB susceptibility in certain strains of mice. CH was induced by subcutaneous injections into naive syngeneic C57BL/6 and BALB/c mice of dinitrophenyl (DNP)-derivatized Thy-1(+)-depleted epidermal cells enriched for Ia+ cells (LC/DNP, 2 x 10(4) cells per mouse). Tolerance was detected by applying 185 microg of DNFB epicutaneously to mice treated 2 wk earlier with a putative tolerating regimen and testing CH expression. We found that LC/DNP obtained from C57BL/6 skin 2 h after UVB irradiation (400 J per m2) failed to induce CH and induced DNP-specific tolerance instead; by contrast, similar cells obtained from same or even higher dose (400 J per m2 and 1200 J per m2) UVB-exposed BALB/c skin induced vigorous CH, and no tolerance was detected. In both C57BL/6 and BALB/c mice, Ia+-depleted EC/DNP neither sensitized naive syngeneic mice nor induced tolerance. LC/DNP prepared from unirradiated trunk skin of either C57BL/6 or BALB/c mice and pre-incubated in vitro for 2 h with cis-UCA, TNF-alpha, or IL-10 failed to induce intense CH; instead, all induced DNP-specific tolerance. Pre-incubation of similar LCs with alpha-MSH in vitro for 2 h also failed to induce CH but did not cause tolerance. Thus, single low-dose UVB irradiation alters the immunogenic and tolerogenic potentials of LCs only in UVB-susceptible mice; by contrast, pre-treatment of LCs with UVB-dependent soluble factors can achieve effects similar to UVB irradiation in both UVB-susceptible and -resistant strains of mice. These findings demonstrate that UVB susceptibility in mice may be determined by the production of UVB-dependent soluble factors within UVB-irradiated skin.

Differential interaction of erythromycin with cytochromes P450 3A1/2 in the endoplasmic reticulum: a CO flash photolysis study

The kinetics of CO binding to cytochromes P450, measured by the flash photolysis technique, were used to probe the interaction of erythromycin with cytochromes P450 in rat liver microsomes. Addition of erythromycin generates substrate difference spectra using microsomes from rats treated with phenobarbital or dexamethasone but not from untreated rats, showing that it binds to P450s induced by these agents. In contrast, erythromycin and/or a monoclonal antibody to P450 3A1/2 accelerated CO binding to microsomes from rats treated with phenobarbital but had no effect on microsomes from untreated or dexamethasone-treated rats. Based on the differential amounts and inducibilities of the P450 3A1 and 3A2 forms in these microsomal samples, these results indicate that erythromycin increased the rate for P450 3A2 but not P450 3A1. The divergent effects of erythromycin on these P450s, which exhibit 89% sequence similarity, were consistent with a model of the P450 substrate binding site in which erythromycin forms a more rigid complex with P450 3A1 than P450 3A2. These results demonstrate the sensitivity of P450 conformation/dynamics to substrate binding, and show that CO binding kinetics can distinguish among closely related P450s in a microsomal environment.

High and low doses of haptens dictate whether dermal or epidermal antigen-presenting cells promote contact hypersensitivity

In the induction of contact hypersensitivity (CH) to an epicutaneously applied hapten, we have previously proposed that low doses of hapten sensitize primarily through epidermal Langerhans' cells (LC), whereas high doses rely largely on dermal antigen-presenting cells (APC). To examine this issue further, we applied either high or low doses of dinitrofluorobenzene (DNFB) epicutaneously to mice. We observed reduced LC density at the site after 12 h (nadir), which returned to normal levels at 24 h only after a low dose of hapten. When a low dose of an unrelated hapten, oxazolone, was painted on skin that had been painted 12 h previously with high dose of DNFB, oxazolone-specific CH was impaired. When grafts of whole skin, dermis alone, and epidermis alone prepared from skin painted 2 h previously with low or high doses of DNFB were placed onto naive, syngeneic mice, CH was induced by whole skin after both types of doses, by epidermis only after a low dose, and by dermis only after high dose. When epidermal cell suspensions were derivatized in vitro with low or high doses of DNFB, only cells exposed to a low dose induced proliferation of hapten-specific Tcells. Thus, only a low dose of hapten reveals the APC functions of LC without the participation of dermal APC.

Differential effects of flavonoids on testosterone-metabolizing cytochrome P450s

Flavonoids are widely distributed phytochemicals, whose modulation of cytochrome P450 mediated carcinogen metabolism is well established. Less well studied is their effect on P450 dependent metabolism of endogenous substrates. To address this question we evaluated a series of twelve flavonoids and hematoxylin for their effect on P450-mediated steroid hydroxylation by rat liver microsomes. Site-specific 7alpha-, 6beta- and 2alpha-hydroxylation of testosterone by P450s 2A1, 3A2 and 2C11, respectively, was measured. Highly selective patterns of inhibition or activation of these P450s were observed. 3,6-dichloro-2'-isopropyloxy-4'-methylflavone was the most potent inhibitor of P450 2C11 while cyanidin chloride most potently inhibited P450s 2A1 and 3A2. The flavonoid analogue hematoxylin was unique in that it activated 2C11 (by 2.5 fold) yet inhibited both 2A1 and 3A2 (by 60%). These results indicate that consumption of dietary flavonoids may likewise alter the metabolite profile of steroids and other physiological P450 substrates.

Application of tilt sensors in functional electrical stimulation

Tilt sensors, or inclinometers have been investigated for the control of Functional Electrical Stimulation (FES) to improve the gait of persons who had a stroke or incomplete spinal cord injury (SCI). Different types of tilt sensors were studied for their characteristics and their performance in measuring the angular displacement of leg segments during gait. Signal patterns of the lower leg with inertial tilt sensors were identified with control subjects and subjects with footdrop who are being stimulated during level walking. To minimize acceleration responses when the foot swings or hits the ground, we use low-pass filtering (1.5-2 Hz). A finite state approach allows the sensor fixed on the shank to effectively detect the step intention in a population of stroke and incomplete SCI subjects and to control the FES. When the lower leg tilts backward, the common peroneal nerve is stimulated to bring the foot up and forward. We have designed a miniature footdrop stimulator with a magnetoresistive tilt sensor built in, so no external sensor cables are required. The thresholds to turn the stimulator on and off can be adjusted, as well as the maximum period of stimulation and the minimum interval between periods of stimulation. This device features several important advantages over traditional AFO's or stimulators controlled by foot switches. Initial trials with stroke and SCI subjects have demonstrated substantial gait improvement for some subjects, while most liked the good cosmesis and ease of using the device with a tilt sensor.

Sensitizing capacity of Langerhans' cells obtained from ultraviolet-B-exposed murine skin

Acute low-dose ultraviolet B (UVB) radiation impairs contact hypersensitivity induction in some strains of mice (called UVB-susceptible, UVB-S), but not in others (called UVB-resistant, UVB-R). In order to determine whether these UVB-dependent phenotypes are inherent properties of epidermal Langerhans' cells, Ia-enriched epidermal cell suspensions were prepared from normal and UVB-exposed skin of C57BL/6 (UVB-S) and BALB/c (UVB-R) mice. After derivatization with dinitrofluorobenzene (DNFB), the cells were injected into footpads of naive syngeneic mice, and the recipients were evaluated for contact hypersensitivity and for in vitro evidence of hapten-specific T-cell priming. The results indicate that DNFB-conjugated Ia-enriched epidermal cells from normal mice, and from UVB-exposed skin of UVB-R mice induced contact hypersensitivity and primed hapten-specific T cells in the draining lymph node. By contrast, epidermal cells from UVB-exposed skin of UVB-S mice failed to induce contact hypersensitivity, even though hapten-specific T cells were still detectable in the draining lymph node. In addition, UVB radiation impaired the ability of hapten-bearing Langerhans' cells from UVB-S mice to activate hapten-specific, primed T cells in vitro. We conclude the traits of UVB-S and UVB-R can be expressed directly by Langerhans' cells, and that these effects are at least in part responsible for the deleterious consequences of UVB radiation on cutaneous immunity in UVB-S mice.

Initial spectroscopic characterization of the ciliate photoreceptor stentorin

Stentorin serves as the primary photosensor in the single cell ciliate, Stentor coeruleus, for its photophobic and phototactic response to light of visible wavelengths. We separated two subunits, stentorin-2A and -2B, from the previous stentorin complex ('stentorin-2') of greater than half a million molecular mass isolated from the photoreceptor organelle (pigment granule). Stentorin-2B bears the chromophore covalently linked to an approx. 50 kDa apoprotein, as determined by SDS-urea-PAGE. Partial amino acid sequences were obtained from this 50 kDa subunit. Its visible and CD spectra were found to be similar to those of stentorin-2. The steady-state and time-resolved fluorescence spectra of stentorin-2B, in H2O and D2O buffers, were also similar to those of stentorin-2. This suggests that the 50 kDa subunit retains the spectral integrity and primary photoreactivity of the stentorin-complex. The picosecond time-resolved fluorescence study revealed that the short picosecond emission component (tau F approximately equal to 8-10 ps) was the predominant emitting species in stentorin-2B and -2, followed by longer decaying species. No deuterium solvent effect was seen in this fast-decaying species. The possible mechanism for the primary photoreaction appears to involve electron transfer coupled with proton transfer.

Relative roles of T cells and macrophages in cytokine-mediated functional transformation of cultured splenic dendritic cells

Splenic dendritic cells resemble epidermal Langerhans cells in the sense that when both cell types are placed in culture for 1 or more days they undergo a functional transformation that equips them to activate unprimed syngeneic T cells. Among Langerhans cells, this transformation has been ascribed to contaminating keratinocytes that are present in cell suspensions prepared from epidermis. Cytokines released from cultured keratinocytes, particularly GM-CSF and IL-1, have been implicated in mediating the functional transformation observed among cultured Langerhans cells. The present experiments have examined the nature of the cytokines responsible for functional conversion of fresh to cultured dendritic cells harvested from spleens of normal mice and have attempted to identify among the cultured cells the cellular source(s) of these factors. The results indicate that splenic dendritic cells acquire unique accessory properties for activation of naive T cells when placed in vitro because factors generated within the culture, especially GM-CSF and IL-1 beta, are present. Our evidence shows that splenic T cells and phagocytic cells, presumably macrophages, contribute to the presence of these conversion-promoting factors. Thus, this evidence suggests that splenic dendritic cells within the spleen of normal mice, like Langerhans cells within the epidermis of normal, unperturbed skin, exist in vivo in a proactive state with respect to the capacity to induce priming among naive T cells. Acquisition of unique accessory cell function depends upon other cell types within spleen, such as T cells and macrophages that secrete GM-CSF and IL-1 beta. These cytokines, as well as other undefined factors, enable dendritic cells to acquire the accessory properties required to activate resting T cells.

Percutaneous transseptal balloon valvuloplasty for dilating mitral valve stenosis (report of 200 cases)

Two hundred cases with mitral valve stenosis were treated by percutaneous single balloon (Inoue balloon) valvuloplasty at our institute from May 1988 to July 1992. The subjects included 137 females and 63 males with a mean age of 36.5 +/- 8.8 years (15-58 years). Hemodynamic and left ventriculographic findings were evaluated immediately before and after the procedure, and the results showed that the mean left atrial pressure was reduced from 25.08 +/- 9.13 mmHg to 10.64 +/- 4.10 mmHg (P < 0.001), the pressure gradient across the mitral valve was reduced from 25.49 +/- 10.22 mmHg to 6.71 +/- 4.87 mmHg (P < 0.001), and systolic pulmonary pressure was reduced from 52.78 +/- 21.42 mmHg to 38.56 +/- 16.47 mmHg (P < 0.001). At the same time, cardiac output and mitral orifice area were increased from 3.84 +/- 0.11 L/min to 4.66 +/- 0.28 L/min (P < 0.001) and from 1.08 +/- 0.28 cm2 to 2.20 +/- 0.47 cm2 (P < 0.001) respectively. Follow-up of 6-48 months (median 24 months) in 50 nonselective patients showed a symptomatic improvement rate of 100%. Percutaneous transseptal balloon mitral valvuloplasty (PBMV) proved to be a highly effective and safe nonsurgical method that can yield very good results in relieving symptomatic rheumatic mitral stenosis, with minimal morbidity and no mortality in this group. PBMV works by splitting the adhered mitral commissures toward the mitral annulus.

Sensory nerve recording for closed-loop control to restore motor functions

A method is developed for using neural recordings to control functional electrical stimulation (FES) to nerves and muscles. Experiments were done in chronic cats with a goal of designing a rule-based controller to generate rhythmic movements of the ankle joint during treadmill locomotion. Neural signals from the tibial and superficial peroneal nerves were recorded with cuff electrodes and processed simultaneously with muscular signals from ankle flexors and extensors in the cat's hind limb. Cuff electrodes are an effective method for long-term chronic recording in peripheral nerves without causing discomfort or damage to the nerve. For real-time operation we designed a low-noise amplifier with a blanking circuit to minimize stimulation artifacts. We used threshold detection to design a simple rule-based control and compared its output to the pattern determined using adaptive neural networks. Both the threshold detection and adaptive networks are robust enough to accommodate the variability in neural recordings. The adaptive logic network used for this study is effective in mapping transfer functions and therefore applicable for determination of gait invariants to be used for closed-loop control in an FES system. Simple rule-bases will probably be chosen for initial applications to human patients. However, more complex FES applications require more complex rule-bases and better mapping of continuous neural recordings and muscular activity. Adaptive neural networks have promise for these more complex applications.

In vitro culture allows splenic dendritic cells to reach their full potential for T-cell activation

Splenic dendritic cells (DCs), bone marrow-derived cells of the presumed monocyte/macrophage lineage, have been used as freshly prepared cells, as well as after overnight culture, to analyze their capacity to activate T cells in vitro with and without cognate antigen being present in the culture. Cultured DCs were found to possess potent accessory properties in vitro, displaying the abilities 1) to activate naive, syngeneic T cells in the absence of cognate antigen, and, after being derivatized with the hapten, dinitrofluorobenzene (DNFB), and 2) to sensitize unprimed, hapten-specific T cells such that the latter were able to mediate DNFB-dependent contact hypersensitivity in normal, unprimed mice. Freshly prepared splenic DCs also displayed accessory cell function; in the presence of the super-antigen, staphylococcal enterotoxin B, fresh DCs induced T-cell proliferation, and, when derivatized with DNFB, fresh DCs activated hapten-specific T cells from in vivo-primed mice. However, in both of these assays, fresh DCs were quantitatively inferior to cultured DCs. We conclude that splenic DCs can exist in two functional forms in vitro, and we propose that the functional properties displayed by freshly obtained cells correspond to the capabilities constitutively displayed by splenic DCs in the normal, unstimulated spleen. In these regards, splenic DCs appear to resemble Langerhans cells after the latter have been exposed to similar culture conditions. The possible relationships between Langerhans cells and DCs are discussed in terms of the role of the cytokine-containing microenvironment in dictating distinct functional properties of antigen-presenting cells.

Time-resolved fluorescence spectroscopy and photolysis of the photoreceptor blepharismin

Blepharismin is the photoreceptor for the photophobic response in the ciliate Blepharisma japonicum (Scevoli, P., Bisi, F., Colombetti, G., Ghetti, F., Lenci, F., and Passarelli, V. (1987) J. Photochem. Photobiol.: B. Biol. 1, 75-84; Lenci, F., Ghetti, F., Gioffre, D., Heelis, P.F., Thomas, B., Phillips, G.O., and Song, P.-S. (1989) J. Photochem. Photobiol.: B. Biol. 3, 449-453). Blepharismin was solubilized from the red cells with 2% n-octylglucopyranoside. A crude pigment-protein preparation was then successively subjected to Bio-Gel A1.5 filtration, FPLC/hydroxyapatite and FPLC/DEAE ion-exchange chromatography. At least two spectrally distinct forms of blepharismin, with the respective absorbance maxima at 597 +/- 1 and 601 +/- 1 nm, were resolved. The steady state fluorescence emission maxima were at 602.5 and 617.5 nm, respectively. The fluorescence decay curves for these pigments were non-exponential. The major component possesses relatively short fluorescence lifetime (200-500 ps) for the former, according to a global analysis. This analysis suggests that the excited state of the shorter wavelength-absorbing form of blepharismin undergoes primary photoprocess faster than that of the free parental chromophore hypericin. Photolysis of blepharismin in solution yielded a irreversible product, accompanied by a 10-12 nm bathochromic shift of the absorbance maximum. However, the mechanistic nature of the time-resolved fluorescence and the photochemistry of blepharismin remains to be elucidated.

Fresh and cultured Langerhans cells display differential capacities to activate hapten-specific T cells

Langerhans cells (LC) that have been cultured for 3 days acquire potent T cell-activating properties when compared to freshly prepared, uncultured LC. By contrast, fresh LC are superior to cultured LC in the ability to process native protein Ag. To define further the disparate functional properties of these epidermally derived APC, freshly isolated and cultured epidermal cells (EC) enriched for LC were prepared from BALB/c mice. Highly purified T cells from naive mice, and from mice sensitized epicutaneously with dinitrofluorobenzene, have been examined for their capacity to respond to fresh and cultured EC; 1) in the presence of staphylococcal enterotoxin B; and 2) after the EC had been derivatized with dinitrofluorobenzene. Both fresh and cultured EC activated syngeneic T cells in the presence of staphylococcal enterotoxin B, and fresh and cultured DNP-derivatized EC induced proliferation among DNP-specific T cells. Only cultured, hapten-derivatized EC were able to activate unprimed syngeneic T cells in vitro, and these cells responded as though "primed" when re-exposed to DNP-derivatized spleen cells in secondary cultures. In addition, naive lymphocytes that were activated by cultured DNP-EC were able to evoke local contact hypersensitivity reactions when injected into the pinnae of naive mice that were then painted with dinitrofluorobenzene. By contrast, naive syngeneic T cells exposed to fresh DNP-EC neither proliferated nor differentiated into effector cells. We conclude that fresh LC can constitutively activate primed, but not unprimed, hapten-specific T cells, whereas cultured LC readily both primed and unprimed T cells. The capacity of hapten-derivatized cultured EC to convert naive, hapten-specific T cells into cells that mediate contact hypersensitivity supports the proposal that cultured LC are the functional equivalents of epidermal LC that have migrated to draining lymph nodes. The ability of hapten-derivatized fresh LC to activate primed, hapten-specific T cells is consistent with the view that fresh LC are functionally equivalent to LC within the epidermis.

Fresh and cultured Langerhans cells display differential capacities to activate hapten-specific T cells

Langerhans cells (LC) that have been cultured for 3 days acquire potent T cell-activating properties when compared to freshly prepared, uncultured LC. By contrast, fresh LC are superior to cultured LC in the ability to process native protein Ag. To define further the disparate functional properties of these epidermally derived APC, freshly isolated and cultured epidermal cells (EC) enriched for LC were prepared from BALB/c mice. Highly purified T cells from naive mice, and from mice sensitized epicutaneously with dinitrofluorobenzene, have been examined for their capacity to respond to fresh and cultured EC; 1) in the presence of staphylococcal enterotoxin B; and 2) after the EC had been derivatized with dinitrofluorobenzene. Both fresh and cultured EC activated syngeneic T cells in the presence of staphylococcal enterotoxin B, and fresh and cultured DNP-derivatized EC induced proliferation among DNP-specific T cells. Only cultured, hapten-derivatized EC were able to activate unprimed syngeneic T cells in vitro, and these cells responded as though "primed" when re-exposed to DNP-derivatized spleen cells in secondary cultures. In addition, naive lymphocytes that were activated by cultured DNP-EC were able to evoke local contact hypersensitivity reactions when injected into the pinnae of naive mice that were then painted with dinitrofluorobenzene. By contrast, naive syngeneic T cells exposed to fresh DNP-EC neither proliferated nor differentiated into effector cells. We conclude that fresh LC can constitutively activate primed, but not unprimed, hapten-specific T cells, whereas cultured LC readily both primed and unprimed T cells. The capacity of hapten-derivatized cultured EC to convert naive, hapten-specific T cells into cells that mediate contact hypersensitivity supports the proposal that cultured LC are the functional equivalents of epidermal LC that have migrated to draining lymph nodes. The ability of hapten-derivatized fresh LC to activate primed, hapten-specific T cells is consistent with the view that fresh LC are functionally equivalent to LC within the epidermis.

[Clinical application of image processing system and quantitative analysis of left ventriculogram and coronary arteriogram]

Currently cine left ventriculography and coronary arteriography are still one of the most important methods in the diagnosis of coronary heart disease and other coronary arterial diseases. An image processing system, called "IA-87 Medical Image Processing System", for quantitative analysis of cine-coronary and left ventricular angiograms has been developed using IBM-PC/AT computer. The major functions of this system are: (1) left ventricular volume determination, i.e. left ventricular contour can be drawn automatically or semi-automatically, the systolic and diastolic volume of the left ventricle are calculated by Simpson's, length-area and chord-length methods. (2) left ventricular segmental wall motion analysis, using rectilinear and polar method, the segmental ejection fraction and normalized segmental contraction are determined. (3) dynamic display of the cardiac cycle. (4) coronary arterial lesion, such as stenosis, can be quantitatively analysed. In a series of cases free from cardiac disease the normal coronary artery (40 cases) and left ventricle (30 cases) were quantitatively analysed using "IA-87 Medical Image Processing System", and the normal value of coronary artery diameter and left ventricular function among Chinese obtained. At the same time, in a series of 45 cases with coronary heart disease (including anterior, posterior wall infarction, and left ventricular aneurysm in 15 respectively), quantitative analysis of the left ventricle was made. The results showed that the system is of significant value for quantitative diagnosis of ischemic heart disease as well as evaluation of therapeutic effect and prediction of prognosis.

[Constituents of the seed coat of Arachis hypogaea L]

From the seed coat of Arachis hypogaea two compounds were isolated. They were identified as the dimer of proanthocyanidin-A type(I) and D-(+)-catechin (II) on the basis of UV, IR, MS, CD, 1H-NMR, 13C-NMR and chemical evidences. It has been found that II is the effective constituent of this plant and I has some active effects as well.

[Cancer and hyperuricemia--an analysis of 316 cancer patients]

Blood uric acid level in patients with solid tumor was seldom reported. Blood uric acid was measured in 316 cancer patients, 173 men and 143 women and was found higher in all patients than in normal subjects. The positive rate for cancer of kidney and urinary bladder was 93.30% and 90.90%, respectively. For other types of cancer, it was 51.27-69.23%. The level of urea was elevated in 75% of the hyperuricemic patients. The mechanisms of hyperuricemia in cancer patients were briefly discussed.