Effect of splenic extract on plasma volume and renal function in the rat

A hypotensive and natriuretic factor has recently been extracted from the rat spleen. Experiments were designed to investigate the mechanisms underlying the increase in urine output caused by splenic extract. Rat spleens were homogenized in phosphate buffered saline (PBS), centrifuged, subjected to ultrafiltration (mol. wt. cutoff 10,000), extracted on C18 affinity columns and dried. After reconstitution in isotonic saline, the extract was injected IV into conscious rats. Splenic extract caused a decrease in plasma volume (17.4+/-1.1 to 15.8+/-1.0 ml at 1 hr), and a delayed increase in urine output (1.8+/-0.2 to 4.0+/-0.4 ml/hr at 2 hr). There were no such changes in the muscle-injected control group. The increase in urine output was accompanied by an increase in glomerular filtration rate (splenic extract, 2.2+/-0.2 to 5.9+/-1.6 ml/min; muscle extract, 2.9+/-0.4 to 3.1+/-0.6 ml/min). Renal blood flow in the splenic extract-injected group fell during the course of the experiment so that, at 120 min., it was significantly lower both with respect to its baseline value and the muscle control group (splenic extract 22.1+/-0.2 to 17.5+/-2.2 ml/min; muscle extract 24.4+/-4.1 to 23.3+/-3.8 ml/min). During this same period, mean arterial pressure in the splenic extract group also fell from 98+/-2 to 91+/-4 mmHg. Renal vascular conductance therefore did not change. In conclusion, splenic extract causes a primary decrease in plasma volume and a delayed increase in urine output that is mediated, at least in part, by an increase in glomerular filtration rate. It is suggested that the splenic factor(s) probably achieves this by differential vasodilatation of the afferent glomerular arteriole and constriction of the efferent glomerular arteriole.

Overexpression of Bcl-2 partly inhibits apoptosis of human cervical cancer SiHa cells induced by arsenic trioxide

OBJECTIVE

To study the biological effect of arsenic trioxide (As2O3) on human cervical cancer SiHa cells and SiHa cells overexpressing bcl-2 gene.

METHODS

SiHa cells with overexpression of Bcl-2 (SiHa-Bcl2 cells) were established by transfecting SiHa cells with Bcl-2 expression vector. The sensitivities of SiHa and SiHa-Bcl2 cells to As2O3 were determined using MTT (Thiazolyl blue) reduction and colony forming ability assay, morphological analysis, flow cytometric analysis, DNA agarose gel electrophoresis, in situ cell death detection (TUNEL), Northern blot, RT-PCR and Western blot.

RESULTS

As2O3 inhibited the growth of SiHa cells and induced G2/M arrest and apoptosis of the cells. RT-PCR and Western blot analysis revealed that As2O3 induced SiHa cell apoptosis possibly via inhibiting the expression of HPV16 E7 and decreasing the expression of c-myc. However, we found that SiHa-Bcl2 cells partly resisted As2O3 induced apoptosis, which might be related to the prevention of the down-regulation of HPV16 E7 and c-myc gene expression. Nevertheless, As2O3 at a high concentration could still induce apoptosis of SiHa-Bcl2 cells mainly via decreasing Bcl-2 expression and slightly inhibiting viral gene expression.

CONCLUSION

As2O3 is an inducer of the apoptosis of human cervical carcinoma cells and the cells overexpressing Bcl-2 can partly resist As2O3 induced apoptosis, but the exact mechanism is unclear.

Intra-atrial communication and control of atrial natriuretic factor (ANF) release

Atrial natriuretic factor (ANF) release was studied in isolated perfused atria prepared from rats. When the vein-atrial junction (VAJ) was distended with an inflatable balloon, ANF release into the perfusate was greater in intact atria than in appendectomized atria. It was concluded that distention of the VAJ causes ANF release from the atrial appendage. A cascade experiment was then prepared whereby buffer from one isolated atrium perfused a second atrium. Although the VAJ of the first atrium could be distended by balloon, the atrial appendage was ligated so ANF was not secreted into the perfusate. The second atrium was intact, but no balloon was inserted. Despite the fact that there were no changes in intraluminal pressure, ANF secretion from the second atrium increased when the VAJ of the first atrium was distended. This response was blocked by the endothelin (ET) A receptor antagonist BQ-123. However, no distention-induced changes in ET-1 levels could be found in the perfusate from the first atrium. It is proposed that, in response to changes in distention of the VAJ, ANF is released remotely from the atrial appendage. The mediator does not appear to be ET-1 itself, but rather some factor that stimulates ET-1-induced ANF release within the tissue of the atrial appendage.

Conditioned immunosuppressive effect of cyclophosphamide on delayed-type hypersensitivity response and a preliminary analysis of its mechanism

In the present study, camphor odor and intraperitoneal (i.p.) injection of cyclophosphamide (CY) were used as conditioned stimulus (CS) and unconditioned stimulus (US), respectively. In the unconditioned group, mice were exposed to camphor odor for 1 h followed by an i.p. injection of CY (75 mg/kg). On the next day, the above CS/US association trial session was repeated followed by smearing dinitrochlorobenzene (DNCB) on mouse abdominal skin for sensitizing the animal for delayed-type hypersensitivity (DTH) response. Five days after DNCB sensitization, mice were exposed to camphor odor (1 h), followed by an i.p. injection of CY, and then DNCB was smeared on the left ear of mice for the challenge of DTH response. Both the left/right ear weight ratio and the activity of leukocyte migration inhibitory factor (LMIF) were used as the index of DTH response, which was done 24 h after DNCB challenge. In the conditioned group, the treatment was the same as that in the unconditioned group, except that normal saline was injected on day 5 instead of CY. Furthermore, in order to analyze the mechanism of the conditioned response (CR), the mouse serum from the conditioned group (CR serum) was injected into normal mice 6 h prior to DNCB challenge. Results showed that in the conditioned group, left/right ear weight ratio and LMIF activity were statistically lower than that in the DTH group, and there was no difference between conditioned and unconditioned groups. Thus, an animal model of conditioned immunosuppressive response had been established. The results also showed that after CR serum was injected into normal mice, DTH response was also significantly suppressed. However, if CR serum was treated with dialysis (10,000 molecular weight cut-off), the suppressive effect of CR serum on DTH response disappeared. Taken together, the data suggested that a chemical compound(s) in serum, with a molecular weight less than 10,000, was important in mediating the conditioned immunosuppressive response. This may be a very important molecule(s) that could be very critical to our understanding of the interaction between the central nervous system and immune function.

Fluid extravasation from spleen reduces blood volume in endotoxemia

We recently demonstrated that fluid is filtered out of the splenic circulation and into the lymphatic system. The current experiments were designed to investigate the importance of this route of fluid extravasation in endotoxemia. Lipopolysaccharide (LPS) was infused into conscious intact and splenectomized rats (150 microg x kg(-1). h(-1) i.v. for 18 h). In the intact rats, mean arterial pressure (MAP) fell from 101+/-2.4 to 88+/-3.9 mm Hg (n = 7) and then stabilized at about 90 mm Hg. Hematocrit rose from 41+/-0.9 to 45+/-0.4% at 40 min, at which time plasma volume had fallen from 4.7+/-0.12 to 4.0+/-0.05 ml/100 g body wt. In the splenectomized rats MAP did not fall and hematocrit did not rise. There also was no change in plasma volume, i.e., splenectomy prevented the hypotension and hemoconcentration customarily induced by LPS. In a second series of experiments, splenic arterial and venous blood flows were simultaneously measured in anesthetized rats infused with LPS (150 microg x kg(-1) x h(-1)). LPS increased splenic fluid efflux. We conclude that during endotoxemia the initial fall in circulating blood volume may be attributed to fluid extravasation from the splenic vasculature.

Characterization, chromosomal localization, and the complete 30-kb DNA sequence of the human Jagged2 (JAG2) gene

The genomic sequence of the human Jagged2 (JAG2) gene, which encodes a ligand for the Notch receptors, was determined. The 30-kb DNA sequence spanning the JAG2 gene contains 26 exons and a putative promoter region. Several potential binding sites for transcription factors, including NF-kappab, E47, E12, E2F, Ets-1, MyoD, and OCT-1, were found in the human JAG2 promoter region. The JAG2 gene was also mapped to the chromosomal region 14q32 using fluorescence in situ hybridization.

Rate and equilibrium constants for protein unfolding and refolding determined by hydrogen exchange-mass spectrometry

Studies of protein unfolding and refolding may help us understand the more general problem of protein folding. Recent studies from this laboratory demonstrated that the unfolding and refolding of a large protein, rabbit muscle aldolase (M(r) 157 kDa), can be studied by combining amide hydrogen exchange and mass spectrometry. Results of these studies indicated that aldolase has three unfolding domains which likely unfold sequentially. Urea was used to increase the populations of partially unfolded states which were labeled with deuterium following a brief exposure to D(2)O. Electrospray ionization mass spectra of both the intact protein and its peptic fragments had multiple envelopes of isotope peaks from which the populations of unfolded forms were determined. The present study extends the previous investigations to include different urea concentrations and kinetic modeling of data taken as the system approaches equilibrium. Analysis of these results gives rate and equilibrium constants describing the unfolding and refolding processes characteristic of aldolase destabilized in urea. The change in solvent-accessible surface, which has been used as a reaction coordinate for protein folding, is estimated from the dependence of the equilibrium and rate constants on the concentration of urea.

[Synthesis and characterization of complex La(C5O3H3)3 x C12H8N2 x H2O]

The title ternary complex La(C5O3H3)3 x C12H8N2 x H2O was synthesized by reaction of lanthanum nitrate with alpha-furoic acid (C5O3H4) and 1,10-phenanthroline (C12H8N2) as ligand in the alcohol solvent. The composition of the complex was determined by element analysis. Its structure and properties were characterized by IR, 1H NMR, UV and TG-DTA. IR, 1H NMR, UV spectra showed that the ligand alpha-furoic acid coordinate to the center ion La (III) with the deprotonized form, and 1, 10-10phenanthroline with the bidentate form using its two N atoms. The TG-DTA analysis exhibited that the complex is stable in the range of room temperature and undergo the disassociation of water and oxygenized decomposition of the organic ligands in order with the rising of temperature, and the final oxide obtained is La2O3. The quantitative analysis of TG-DTA was coincided with the structural composition of the title complex.

Hydrogen exchange demonstrates three domains in aldolase unfold sequentially

Rabbit muscle aldolase is a homotetramer in which the subunits have a classical alpha/beta-barrel structure and Mr 39,212 Da. We have previously reported that aldolase incubated in 3 M urea has three unfolding domains distinguished by their different unfolding rates. The unfolding rates of these domains were determined from isotope patterns in the mass spectra of peptic fragments derived from aldolase incubated in 3 M urea and pulse labeled in (2)H2O. The present study extends this investigation to more thoroughly characterize the structures of these unfolding intermediates. Mass spectra of intact monomers had four envelopes of isotope peaks corresponding to four structural forms of aldolase. Analysis of the present results suggests that these structural forms consist of native aldolase and three forms that have one to three domains unfolded. The molecular masses of these four structural forms indicate that there are 107 residues in each of the three unfolding domains of aldolase. Present results also show that aldolase remains a tetramer in 4 M urea, even though hydrogen exchange and circular dichroism indicate that it has lost most of its secondary and tertiary structure. The abundances of unfolded domains, which were determined from mass spectra of either intact aldolase or its peptic fragments, were used to determine the abundances of specific, partially unfolded forms of aldolase. Kinetic modeling of the abundances of these structures suggests that these structures are formed sequentially as aldolase unfolds in urea.

[Ciliary neurotrophic factor in the regeneration of facial nerve]

OBJECTIVE

To study the role of CNTF in regeneration of facial nerve.

METHOD

SD Rat facial nerves in temporal bones were transected and then combined end to end. In ciliary neurotrophic factor group (n = 30), lesions were covered by gelatin sponge soaked with CNTF. In control group (n = 18), lesions were covered by gelatin sponge soaked with normal saline. 2, 4, 12 weeks after the operation, both CNTF group and SAL group undergone electrophysiology test and histopathology as well as quantity analysis.

RESULT

Two weeks later, both CNTF and SAL group failed in eliciting muscular excitement by stimulating facial nerve; T-test showed significant difference between the two groups(P < 0.05) about the average of myelinated axons 4 weeks later, the latency of facial muscular excitement was 7.650 +/- 2.702 ms in CNTF group and 16.080 +/- 0.162 ms in SAL group. The average number of myelinated axons was 1614 +/- 411 in experimental group and 1094 +/- 343 in control group. T-test showed significant difference between them (P < 0.05). 12 weeks later, latency of facial muscle excitement was 2.016 +/- 0.122 ms in CNTF group and 2.060 +/- 0.162 ms in SAL group. The average number of myelinated axons was 1909 +/- 332 in experimental group and 1847 +/- 422 in control group. T-test showed no significant difference between the two groups (P > 0.05).

CONCLUSION

CNTF enhance facial nerve regeneration in adult SD rats.

Cubic membrane structure in amoeba (Chaos carolinensis) mitochondria determined by electron microscopic tomography

Cubic membranes occur in a variety of membrane-bound organelles in many cell types. By transmission electron microscopy (TEM) these membrane systems appear to consist of highly curved periodic surfaces that fit mathematical models analogous to those used to describe lipidic cubic phases. For the first time, a naturally occurring cubic membrane system has been reconstructed in three dimensions by electron microscopic tomography, and its periodicity directly characterized. Double-tilt tomographic reconstruction of mitochondria in the amoeba, Chaos carolinensis, confirms that their cristae (inner membrane infoldings) have the cubic structure suggested by modeling studies based on thin-section TEM images. Analysis of the membrane surfaces in the reconstruction reveals the connectivity of the internal compartments within the mitochondria. In the cubic regions, the matrix is highly condensed and confined to a continuous, small space between adjacent cristal membranes. The cristae form large, undulating cisternae that communicate with the peripheral (inner membrane) compartment through narrow tubular segments as seen in other types of mitochondria. The cubic periodicity of these mitochondrial membranes provides an ideal specimen for measuring geometrical distortions in biological electron tomography. It may also prove to be a useful model system for studies of the correlation of cristae-matrix organization with mitochondrial activity.

[Observation of distortion product otoacoustic emissions in recovery course of sudden deafness]

OBJECTIVE

To realize the DPOAE resulting in sudden deafness and to investigate the changes of OAE in the recovery course of sudden deafness.

METHOD

The basic characters of distortion product OAE (DPOAE) were studied in 60 ears of 30 cases with sudden deafness. The treatment and following-up were carried on too.

RESULT

The incidence and amplitude of OAEs in the affected ears were lower than that of normal ears and normal group, and the threshold of DPOAE was higher too. In the recovery course the amplitude and threshold of DPOAE were improved with the restoration of auditory threshold, but the restoring rate (RR) of auditory threshold was higher.

CONCLUSION

The DPOAE in sudden deafness implies a serious sensorineural hearing loss. In the recovery course, the amplitude and threshold of DPOAE is later than that of the pure-tone behavioral threshold, which implies that DPOAE is a sensitive and direct way in reflecting the function of cochlea.

Diphtheria in the Republic of Georgia: use of molecular typing techniques for characterization of Corynebacterium diphtheriae strains

Sixty-six Corynebacterium diphtheriae strains (62 of the gravis biotype and 4 of the mitis biotype) isolated during the Georgian diphtheria epidemic of 1993 to 1998 and 13 non-Georgian C. diphtheriae strains (10 Russian and 3 reference isolates) were characterized by (i) biotyping, (ii) toxigenicity testing with the Elek assay and PCR, (iii) the randomly amplified polymorphic DNA (RAPD) technique, and (iv) pulsed-field gel electrophoresis (PFGE). Fifteen selected strains were ribotyped. Six RAPD types and 15 PFGE patterns were identified among all strains examined, and 12 ribotypes were found among the 15 strains that were ribotyped. The Georgian epidemic apparently was caused by one major clonal group of C. diphtheriae (PFGE type A, ribotype R1), which was identical to the predominant epidemic strain(s) isolated during the concurrent diphtheria epidemic in Russia. A dendrogram based on the PFGE patterns revealed profound differences between the minor (nonpredominant) epidemic strains found in Georgia and Russia. The methodologies for RAPD typing, ribotyping, and PFGE typing of C. diphtheriae strains were improved to enable rapid and convenient molecular typing of the strains. The RAPD technique was adequate for biotype differentiation; however, PFGE and ribotyping were better (and equal to each other) at discriminating between epidemiologically related and unrelated isolates.

Simultaneous determination of formaldehyde and methylglyoxal in urine: involvement of semicarbazide-sensitive amine oxidase-mediated deamination in diabetic complications

The deamination of methylamine and aminoacetone by semicarbazide-sensitive amine oxidase (SSAO) produces formaldehyde and methylglyoxal, respectively, which have been presumed to be involved in diabetic complications. A high-performance liquid chromatography procedure using 2,4-dinitrophenylhydrazine (DNPH) as a derivatizing agent is developed to determine endogenous formaldehyde, methylglyoxal, malondialdehyde, and acetaldehyde. The devised DNPH method is sensitive enough to analyze aldehyde levels in urine. An increase in the excretion of formaldehyde, methylglyoxal, and malondialdehyde is confirmed in streptozotocin-induced diabetic rats. Following the chronic administration of methylamine, the urinary levels of both formaldehyde and malondialdehyde (a product from lipid peroxidation) are found to be substantially increased. A potent selective SSAO inhibitor, (E)-2-(4-fluorophenethyl)-3-fluoroallylamine hydrochloride (MDL-72974A), reduced the formation of formaldehyde, methylglyoxal, and malondialdehyde. The increase of the cytotoxic aldehyde levels as a result of increased SSAO-mediated deamination may occur in some pathological conditions.

Grb10, a positive, stimulatory signaling adapter in platelet-derived growth factor BB-, insulin-like growth factor I-, and insulin-mediated mitogenesis

Grb10 has been described as a cellular partner of several receptor tyrosine kinases, including the insulin receptor (IR) and the insulin-like growth factor I (IGF-I) receptor (IGF-IR). Its cellular role is still unclear and a positive as well as an inhibitory role in mitogenesis depending on the cell context has been implicated. We have tested other mitogenic receptor tyrosine kinases as putative Grb10 partners and have identified the activated forms of platelet-derived growth factor (PDGF) receptor beta (PDGFRbeta), hepatocyte growth factor receptor (Met), and fibroblast growth factor receptor as candidates. We have mapped Y771 as a PDFGRbeta site that is involved in the association with Grb10 via its SH2 domain. We have further investigated the putative role of Grb10 in mitogenesis with four independent experimental strategies and found that all consistently suggested a role as a positive, stimulatory signaling adaptor in normal fibroblasts. (i) Complete Grb10 expression from cDNA with an ecdysone-regulated transient expression system stimulated PDGF-BB-, IGF-I, and insulin- but not epidermal growth factor (EGF)-induced DNA synthesis in an ecdysone dose-responsive fashion. (ii) Microinjection of the (dominant-negative) Grb10 SH2 domain interfered with PDGF-BB- and insulin-induced DNA synthesis. (iii) Alternative experiments were based on cell-permeable fusion peptides with the Drosophila antennapedia homeodomain which effectively traverse the plasma membrane of cultured cells. A cell-permeable Grb10 SH2 domain similarly interfered with PDGF-BB-, IGF-I-, and insulin-induced DNA synthesis. In contrast, a cell-permeable Grb10 Pro-rich putative SH3 domain binding region interfered with IGF-I- and insulin- but not with PDGF-BB- or EGF-induced DNA synthesis. (iv) Transient overexpression of complete Grb10 increased whereas cell-permeable Grb10 SH2 domain fusion peptides substantially decreased the cell proliferation rate (as measured by cell numbers) in normal fibroblasts. These experimental strategies independently suggest that Grb10 functions as a positive, stimulatory, mitogenic signaling adapter in PDGF-BB, IGF-I, and insulin action. This function appears to involve the Grb10 SH2 domain, a novel sequence termed BPS, and the Pro-rich putative SH3 domain binding region in IGF-I- and insulin-mediated mitogenesis. In contrast, PDGF-BB-mediated mitogenesis appears to depend on the SH2 but not on the Pro-rich region and may involve other, unidentified Grb10 domains. Distinct protein domains may help to define specific Grb10 functions in different signaling pathways.

Comparison of continuous and pulsed labeling amide hydrogen exchange/mass spectrometry for studies of protein dynamics

In contrast to the rigid structures portrayed by X-ray diffraction, proteins in solution display constant motion which leads to populations that are momentarily unfolded. To begin to understand protein dynamics, we must have experimental methods for determining rates of folding and unfolding, as well as for identifying structures of folding and unfolding intermediates. Amide hydrogen exchange has become an important tool for such measurements. When urea is used to stabilize unfolded forms of proteins, the refolding rates may become slower than the rates of isotope exchange. In such cases, the intermolecular distribution of deuterium among the entire population of molecules may become bimodal, giving rise to a bimodal distribution of isotope peaks in mass spectra of the protein or its peptic fragments. When the protein is exposed continuously to D2O, the relative intensities of the two envelopes of isotope peaks give an integrated account of populations participating in the folding/unfolding process. However, when the protein is exposed only briefly to D2O, the relative intensities of the two envelopes of isotope peaks give an instantaneous measure of the folded/unfolded populations. Application of these two labeling methods to a large protein, aldolase, is described along with a discussion of specific parameters required to optimize these experiments.

IL-5 contributes to worm expulsion and muscle hypercontractility in a primary T. spiralis infection

Enteric nematode infections lead to increased interleukin (IL)-5 expression, eosinophilic inflammation, and intestinal smooth muscle hypercontractility. Although eosinophils release inflammatory mediators that cause smooth muscle contraction, the role of IL-5 and eosinophils in enteric smooth muscle hypercontractility is unclear. IL-5-deficient mice and their wild-type controls were infected with the nematode Trichinella spiralis. Intestinal parasites and eosinophils were counted, and jejunal longitudinal muscle contractility was assessed. During infection, IL-5 gene expression increased significantly in wild-type mice and was accompanied by significant intestinal eosinophilia in wild-type but not IL-5-deficient mice. Although both strains developed increased muscle contractility during infection, contraction was significantly less in the IL-5-deficient mice at days 16 and 21 postinfection. In addition, parasite expulsion was transiently delayed at day 16 in IL-5-deficient mice. Thus, in the nematode-infected mouse, IL-5 appears essential for intestinal eosinophilia and contributes to, but is not essential for, the development of muscle hypercontractility. IL-5 also appears to play a minor role in expelling a primary T. spiralis infection from the gut.

[Observation of special stain and ultrastructure of lattice, granular and macular corneal dystrophy]

OBJECTIVE

To investigate the histopathological changes of lattice, granular and macular corneal dystrophy.

METHODS

Corneal buttons were obtained from penetrating keratoplasty due to severe corneal dystrophy, and their sections and ultrathin sections with several special stains were observed under a light microscope (LM) and electron microscope (EM).

RESULTS

In cases with lattice dystrophy, the stromal fusiform deposits seen under LM were confirmed to be amorphous materiel with filaments by EM and stained positively for Masson trichrome, PAS and Congo red. In cases with granular dystrophy, the granular or bread debris deposits found between laminae under LM were extracellular material observed by EM and they were stained positively for Masson trichrome and alcian blue. In cases with macular dystrophy, the stromal spheroid or macular deposits were seen under LM, and there were numerous vacuoles containing fibrils and granules in the cytoplasm of keratocytes and accumulative amorphous material in the stroma under EM; the deposits were positive for colloidal iron and alcian blue stain.

CONCLUSION

In corneal lattice dystrophy, there are amyloid deposits; in granular dystrophy, there are extracellular material deposits; and in macular dystrophy, there is mucopolysaccharide accumulation.

A Phase I study of active immunotherapy with carcinoembryonic antigen peptide (CAP-1)-pulsed, autologous human cultured dendritic cells in patients with metastatic malignancies expressing carcinoembryonic antigen

Dendritic cells (DCs), antigen-presenting cells capable of priming naive T cells to specific antigens in an HLA-restricted fashion, have been demonstrated to induce protective T cell-mediated immunity in tumor-bearing animals. We performed this study to test the safety, feasibility, and clinical response of immunizations with in vitro-generated DCs, loaded with an HLA-A2-restricted peptide fragment of the tumor antigen carcinoembryonic antigen (CEA), for the treatment of patients with advanced CEA-expressing malignancies. Cell preparations enriched for autologous DCs were generated from the patients' plastic adherent peripheral blood mononuclear cells in serum-free media supplemented with granulocyte macrophage colony-stimulating factor and interleukin-4. Within the cell preparation, 66% of the cells expressed the phenotype typical for DCs (CD86high, HLA-DRhigh, and CD14low). The DCs were loaded with the CEA peptide CAP-1 and cryopreserved. Groups of three to six patients received four weekly or biweekly i.v. infusions of the CAP-1-loaded DC in escalating dose levels of 1 x 10(7), 3 x 10(7), and 1 x 10(8) cells/dose. A subset of the patients in the last group also received intradermal injections of 1 x 10(6) DCs. There were no toxicities directly referable to the treatments. One patient had a minor response, and one had stable disease. Skin punch biopsy at DC injection sites demonstrated pleomorphic infiltrates in the three patients evaluated. We conclude that it is feasible and safe to generate and administer large numbers of previously cryopreserved DCs loaded with CAP-1 peptide to patients with advanced malignancies.

[Effects of Dexamethasone, Fluorometholone and Florex on intraocular pressure after photorefractive keratectomy]

To evaluate the results of elevated intraocular pressure (IO) secondary to dropping of 0.1% Dexamethasone, Fluorometholone and Florex for 1-3 months after photorefractive keratectomy, we summed up and analysed the 3-month follow-up data on 546 eyes in three groups. The rates of IO elevated in Dexamethasone, Fluorometholone and Florex were 36%, 12.4% and 31.9% respectively. After topical use of corticosteroid, some of the elevations of IO took place as early as two weeks, but most of them occurred around 1 month. Eleven patients with IO elevation of both eyes had visual acuity decreased associated with eye-ache and halos and the other patients had no symptoms. After discontinuation of corticosteroid and institution of antiglaucoma therapy, the IO became normal in 3-7 days. In practice, this means that patients receiving corticosteroid eyedrops for more than two weeks should be checked for the possibility of ocular hypertension to prevent the corticosteroid glaucoma.

Assessment of the deamination of aminoacetone, an endogenous substrate for semicarbazide-sensitive amine oxidase

Methylglyoxal, a toxic aldehyde, has been reported to be increased in diabetes and has been claimed to be related to diabetic complications. Aminoacetone, an intermediate in the metabolism of threonine and glycine, has been proposed to be an endogenous substrate for semicarbazide-sensitive amine oxidase (SSAO). Methylglyoxal is the product. An HPLC procedure for the determination of SSAO activity toward aminoacetone in vitro is described. It was observed in previous assays that methylglyoxal formed via deamination of aminoacetone was quite unstable and led to erroneous results. o-Phenylenediamine (o-PD) was therefore employed for derivatization of methylglyoxal. o-PD does not affect SSAO activity and can be included in the enzyme reaction mixture for continuous trapping of methylglyoxal. This can avoid the loss of methylglyoxal during incubation. Deamination of aminoacetone by human umbilical artery SSAO was confirmed with this improved assay. The values of Km and Vmax, are 125.9 +/- 20.5 microM and 332.2 +/- 11.7 nmol/h/mg protein, respectively. Deamination of aminoacetone was nearly completely inhibited by 1 mM semicarbazide and 1 microM MDL-72974A, a potent selective SSAO inhibitor, whereas MAO inhibitors clorgyline (1 mM) and deprenyl (1 mM) had no inhibitory effect.

Behavior of acid-adapted and unadapted Escherichia coli O157:H7 when exposed to reduced pH achieved with various organic acids

A study was done to determine if various organic acids differ in their inhibitory or lethal activity against acid-adapted and unadapted Escherichia coli O157:H7 cells. E. coli O157:H7 strain EO139, isolated from venison jerky, was grown in tryptic soy broth (TSB) and in TSB supplemented with 1% glucose (TSBG) for 18 h at 37 degrees C, then plated on tryptic soy agar (TSA) acidified with malic, citric, lactic, or acetic acid at pH 5.4, 5.1, 4.8, 4.5, 4.2, and 3.9. Regardless of whether cells were grown in TSB or TSBG, visible colonies were not formed when plated on TSA acidified with acetic, lactic, malic, or citric acids at pH values of < or =5.4, < or =4.5, < or =4.2, or < or =4.2, respectively. Cells not adapted to reduced pH did not form colonies on TSA acidified with lactic acid (pH 3.9) or acetic acid (pH 3.9 and 4.2); however, a portion of acid-adapted cells remained viable on TSA containing lactic acid (pH 3.9) or acetic acid (pH 4.2) and could be recovered in TSB. Inactivation of acid-adapted cells was less than that of unadapted cells in TSB acidified at pH 3.9 with citric, lactic, or acetic acid and at pH 3.4 with malic acid. Significantly (P< or =0.05) higher numbers of acid-adapted cells, compared with unadapted cells, were detected 12 h after inoculation of TSB acidified with acetic acid at pH 3.9; in TSB containing lactic acid (pH 3.9), the number of acid-adapted cells was higher than the number of unadapted cells after 5 h. In TSB acidified at pH 3.9 with citric acid or pH 3.4 with malic acid, significantly higher numbers of acid-adapted cells survived. This study shows that organic acids differ in their inhibitory or lethal activity against acid-adapted and unadapted E. coli O157:H7 cells, and acid-adapted cells are more tolerant than unadapted cells when subsequently exposed to reduced pH caused by these acids.

The seroepidemiology of genogroup 1 and genogroup 2 Norwalk-like viruses in Italy

Southampton virus (SV) and Lordsdale viruses (LV) are small round structured viruses characterised recently and belong to two separate genogroups. The capsid genes of these viruses were expressed in insect cells using recombinant baculoviruses. Both SV (genogroup 1) and LV (genogroup 2) capsid proteins self-assembled to form virus-like particles (VLPs). The VLPs were used in a standard enzyme-linked immunosorbent assay (ELISA) to screen for antibodies to SV and LV in 1,729 age-stratified human sera collected in Verona, Italy between January and November 1996. SV VLPs were labile compared with LV VLPs. There was a large difference in the prevalence of SV (28.7%) compared with LV (91.2%). However, presentation of SV VLPs using chicken egg yolk antibody-coated wells (IgY capture ELISA) with a subset of serum samples from patients (0-19 years) increased the number of positive sera significantly (50.5%), indicating that SV antigen integrity is an important factor in the assay. Recent reverse transcription-polymerase chain reaction (RT-PCR) studies have shown that LV is circulating currently and analysis of IgY capture ELISA data showed greater reactivity for LV than SV, reflecting a genuinely lower rate of recent infection by this genogroup 1 virus.

[Respiratory monitoring and high frequence jet ventilation (HFJV) in the treatment of severe chest injuries]

Twenty-eight patients with severe chest injuries were classified into 3 groups: fractures of rib, hemopneumothorax and lung injured. Their respiratory rate (RR), SpO2 and blood gas were analysed. The results showed that SpO2 and PaO2 in lung-injured group were the lowest and RR was the highest in the 3 groups. After HFJV, there was a significant rise in PaO2 and SpO2 (P < 0.05) and a gradual recovery of respiratory and pulse rates in lung-injured group. The results suggest that respiratory monitoring is important for patients with chest injuries and HFJV may be used as an effective ventilation method for treating patients with severe chest injuries.