Solid-substrate fermentation of soybeans with Rhizopus spp.: Comparison of discontinuous rotation with stationary bed fermentation

Tempe is a soybean food obtained by stationary solid-substrate fermentation using moulds (mainly Rhizopus spp.) as starter organism. Traditionally, tempe is fermented in static layer trays or wrapped packages. Due to heat and mass transfer limitations, gradients of temperature and gas atmosphere will result. Agitated fermentation can help to level heat and mass gradients, yielding better homogeneity. This type of process will not result in traditional tempe, but in individually fermented soybeans that could be processed into food ingredients. This report deals with the comparative effect of stationary versus agitated solid-substrate fermentation of soybeans on some chemical indices of substrate modification. For agitated solid-substrate fermentation, a 450-l size rotary-drum bioreactor was designed and constructed. Of two Rhizopus spp. tested, R. microsporus tolerated agitation quite well, as judged by changes of pH, amino nitrogen, ammonia, and soluble dry matter. The other species, R. oligosporus was strongly affected by agitation. This resulted in less pH increase (difference approx. 1.5 units), lower amino nitrogen levels (30-50% of levels in static fermentation), and lower levels of water-soluble non-lipid dry matter (30-50% of levels in static fermentation) with R. oligosporus agitated fermentation of soybeans controlled at 30 and 37 degrees C, compared to static fermentation at temperatures ranging between 25-35 and 30-40 degrees C, respectively.

Brain-wave recognition of sentences

Electrical and magnetic brain waves of two subjects were recorded for the purpose of recognizing which one of 12 sentences or seven words auditorily presented was processed. The analysis consisted of averaging over trials to create prototypes and test samples, to each of which a Fourier transform was applied, followed by filtering and an inverse transformation to the time domain. The filters used were optimal predictive filters, selected for each subject. A still further improvement was obtained by taking differences between recordings of two electrodes to obtain bipolar pairs that then were used for the same analysis. Recognition rates, based on a least-squares criterion, varied, but the best were above 90%. The first words of prototypes of sentences also were cut and pasted to test, at least partially, the invariance of a word's brain wave in different sentence contexts. The best result was above 80% correct recognition. Test samples made up only of individual trials also were analyzed. The best result was 134 correct of 288 (47%), which is promising, given that the expected recognition number by chance is just 24 (or 8.3%). The work reported in this paper extends our earlier work on brain-wave recognition of words only. The recognition rates reported here further strengthen the case that recordings of electric brain waves of words or sentences, together with extensive mathematical and statistical analysis, can be the basis of new developments in our understanding of brain processing of language.

Detection and quantitation of a sodium-dependent sulfate cotransporter (NaSi-1) by sandwich-type enzyme-linked immunosorbent assay

The sodium-dependent sulfate transporter (NaSi-1) DNA has been recently identified from rat kidney cortex. The objective of this study was to develop a quantitative assay for the NaSi-1 transporter protein. The NaSi-1 antigen was prepared by fusion protein techniques following analysis of the primary sequence for antigenicity. Polyclonal and monoclonal antibodies against the NaSi-1 antigen were raised in rabbits and mice, respectively. The specificity of the raised antibodies was examined by Western analysis using brush-border membrane (BBM) and basolateral membrane (BLM) purified from rat kidney cortex. Both NaSi-1 polyclonal and monoclonal antibodies detected a 69-kDa protein in the BBM. Using the purified monoclonal antibody as the capture antibody and the polyclonal antibody as the detecting antibody, a simple and sensitive sandwich-type enzyme-linked immunosorbent assay was developed to quantitate NaSi-1 transporter protein levels in tissue. The specificity of the assay was examined using BBM, BLM and NaSi-1-transfected Madin-Darby canine kidney cells. The assay was capable of detecting NaSi-1 at levels as low as 6.58 fmol. The concentration of NaSi-1 transporter protein in crude membrane isolated from rat kidney cortex was 0.094+/-0.014 fmol/ microg protein (mean+/-SD of three preparations).

Estimation of target hazard quotients and potential health risks for metals by consumption of seafood in Taiwan

The purpose of this paper is to describe the impact of metal pollution on the main seafood and assess the potential health risk from consuming the contaminated seafood in Taiwan. The results of geometric mean (GM) metal concentrations in various seafood showed that the copper, zinc, and arsenic concentrations in oysters were significantly (p < 0.001) higher than those in the other seafood by about 1,057, 74.3, and 56.2 times, respectively. The green color found in the oysters was due to high GM copper and zinc concentrations of 909 (ranging from 113-2,805) and 1,293 (ranging from 303-3,593) microg/g dry wt, respectively. In addition, using a maximum consumption rate of 139 g/day of oysters for individuals, calculations yield target hazard quotients (daily intake/reference dose) of below 1 for cadmium and mercury and high values of 1.61, 9. 33, and 1.77 for inorganic arsenic, copper, and zinc in adults, respectively. The various lifetime cancer risks for inorganic arsenic (maximum exposed individuals risk ranging from 9.93 x 10(-6) to 3.11 x 10(-4)) might be caused by consuming different seafood in Taiwan. The highest risk estimate for inorganic arsenic was 5.10 x 10(-4) for consumption of oysters by Machu Islands residents. The long-term exposure of metals through consumption of oysters, especially for some high-risk groups, could be dangerous. Taking inorganic arsenic for example, a 10(-6) upper limit on lifetime risk as the health protection standard would require maximum oyster residue levels of approximately 0.0076-0.056 microg/g wet wt, for consumption rates of 139-18.6 g/d. In the light of known risks to public health, the government should issue an immediate warning to the public to refrain from eating all seafood harvested from the Taiwan coastal areas, especially the Hsiangshan area and the Machu Islands.

The use of a chimera HIV-1/HIV-2 envelope protein for immunodiagnosis of HIV infection: its expression and purification in E. coli by use of a translation initiation site within HIV-1 env gene

A chimera HIV-1/HIV-2 envelope sequence composed of multiple conserved immunodominant epitopes of HIV-1 envelope protein (HIV-1 IIIB: env482-518 + env548-675) and the HIV-2 gp36 immunodominant epitope (env592-603), was constructed and directly over-expressed in E. coli by using a prokaryotic translation initiation sequence contained within the gene of HIV-1 envelope. The recombinant product was purified and applied in antibody-screening assay. The purified chimera antigen reacted with all the thirty-eight HIV-1 positive serum samples, the two HIV-2 serum samples, and had no cross-reaction with all the eighty-eight normal healthy serum sample. The results indicated that this recombinant chimera HIV-1/HIV-2 envelope protein could be useful for diagnostic purposes of HIV infection.

User-friendly and versatile software for analysis of protein hydrophobicity

We have developed a simple and flexible program to analyze regional hydrophobicity of a protein from its amino acid (aa) sequence. This program runs as a Microsoft Excel document into which aa sequence can be copied from any Windows-compatible or Macintosh word processor. The program returns the hydrophobicity index of each aa residue and other analyses that can be used to predict transmembrane domains, amphiphilic alpha helices and putative antigenic epitopes in a protein using established algorithms. The program can also be easily modified to test user-defined algorithms and to accommodate non-conventional aa residues or ambiguities in the aa sequence. Simple modification of the program allows direct use of nucleic acid sequence information for various analyses. Graphic visualization of the results is readily achieved using the graphics function of Microsoft Excel. Alternatively, the data can be imported into other graphics software for preparation of publication-quality figures. By running as a document in Microsoft Excel, which can be found in virtually all personal computers, this program provides easy access even to the computer novice.

Repin-induced neurotoxicity in rodents

Russian knapweed is a perennial weed found in many parts of the world, including southern California. Chronic ingestion of this plant by horses has been reported to cause equine nigropallidal encephalomalacia (ENE), which is associated with a movement disorder simulating Parkinson's disease (PD). Repin, a principal ingredient purified from Russian knapweed, is a sesquiterpene lactone containing an alpha-methylenebutyrolactone moiety and epoxides and is a highly reactive electrophile that can readily undergo conjugation with various biological nucleophiles, such as proteins, DNA, and glutathione (GSH). We show in this study that repin is highly toxic to C57BL/6J mice and Sprague-Dawley rats and acutely induces uncoordinated locomotion associated with postural tremors, hypothermia, and inability to respond to sonic and tactile stimuli. We also show that repin intoxication reduces striatal and hippocampal GSH and increases total striatal dopamine (DA) levels in mice. Striatal microdialysis in rats, however, has demonstrated a significant reduction of extracellular DA levels. These findings, coupled with the absence of any demonstrable change in striatal DOPAC levels, suggest that repin acts by inhibiting DA release, a hypothesis that is further supported by our demonstration that, in cultured PC12 cells, repin inhibits the release of DA without affecting its uptake. We believe, therefore, that inhibition of DA release represents one of the earliest pathogenetic events in ENE, leading eventually to striatal extracellular DA denervation, oxidative stress, and degeneration of nigrostriatal pathways. Since the neurotoxic effects of repin appear to be mediated via oxidative stress, and since repin is a natural product isolated from a plant in our environment that can cause a movement disorder associated with degeneration of nigrostriatal pathways, clarification of the mechanism of repin neurotoxicity may provide new insights into our understanding of the pathogenesis of PD.

Inhibition of cathepsin B does not affect the intracellular activation of trypsinogen by cerulein hyperstimulation in isolated rat pancreatic acinar cells

Activation of trypsinogen is thought to trigger the autodigestive process in acute pancreatitis. The lysosomal enzyme cathepsin B was suggested to cause the activation of trypsinogen because it is known that cathepsin B is able to activate trypsinogen in special circumstances and that lysosomal and digestive enzymes are colocalized within intracellular vacuoles in the early stage of pancreatitis. As yet this hypothesis has been difficult to prove because activated trypsin is difficult to quantify in pancreatitis by conventional enzymatic measurements. We therefore employed an ELISA for trypsin activating peptide (TAP), which is a small peptide cleaved during the activation of trypsinogen and can be determined reliably. Supraphysiological concentrations of cerulein (1 nM-1 microM) resulted in a marked increase in TAP in freshly isolated pancreatic acinar cells, indicating activation of trypsinogen. This activation as determined by the TAP increase was significantly reduced by the serine protease inhibitor Fut-175 but not by the cathepsin B inhibitors E-64 and NCO-700. The concentrations of NCO-700 and E-64 abolished the cathepsin B activity of pancreatic acinar cells but did not significantly reduce the trypsin activity (after enterokinase preincubation); correspondingly the concentrations of Fut-175 used abolished the trypsin activity but did not reduce the cathepsin B activity. The results indicate that an autoactivation of trypsin rather than an activation of trypsinogen by cathepsin B triggers trypsin activation by supramaximal cerulein concentrations.

Brain wave recognition of words

Electrical and magnetic brain waves of seven subjects under three experimental conditions were recorded for the purpose of recognizing which one of seven words was processed. The analysis consisted of averaging over trials to create prototypes and test samples, to both of which Fourier transforms were applied, followed by filtering and an inverse transformation to the time domain. The filters used were optimal predictive filters, selected for each subject and condition. Recognition rates, based on a least-squares criterion, varied widely, but all but one of 24 were significantly different from chance. The two best were above 90%. These results show that brain waves carry substantial information about the word being processed under experimental conditions of conscious awareness.

[Surgical treatment of extrahepatic bile duct carcinoma]

OBJECTIVE

To evaluate the experience in the diagnosis and surgical treatment of the extrahepatic bile duct carcinomas.

METHODS

242 patients with extrahepatic bile duct carcinoma over the past 20 years was retrospectively studied.

RESULTS

The origin points were carcinomas of the upper bile duct in 168, of the middle bile duct in 18, and of the lower bile duct in 56 patients. The preoperative diagnostic rates for the location and the nature of the lesion were respectively raised to 97.2% and 94.5% by combination of ultrasonography and CT. The curative resection rates for the tumors in the upper, middle, and lower bile duct over the recent five years reached to 50.0%, 50.0% and 71.4%. respectively. Follow-up of patients with curative resection showed a one year recurrent rate of 73.9% and a three year recurrent rate of 100.0% with a mean recurrent time of 9.6 months in patients with local metastasis, in contrast to 13.3%, 71.4% and 17.5 months in those without metastasis. Metastasis was mainly responsible for the recurrence. Liver or multiple organ failure, intra-abdominal infection and gastrointestinal hemorrhage were the common and serious complications.

CONCLUSION

The case number of the bile duct carcinoma presented a remarkable increment tendency. Ultrasonography and CT were satisfactory enough for diagnosis. To reduce the recurrent rate, resection of the tumor together with the lymph, nervous, fatty and connective tissues in the hepatic hilus, even the right celiac ganglia, should be considered the necessary procedure. Monitoring and protecting the main organs to prevent the multiple organ failure, controlling the gastrointestinal hemorrhage and the intra-abdominal infection are important to decreasing the mortality.

Cell volume changes modulate cholecystokinin- and carbachol-stimulated amylase release in isolated rat pancreatic acini

BACKGROUND & AIMS

Changes in cell volume have been recently identified as modulators of cell function and gene expression. This study evaluated the regulation of exocrine secretion by pancreatic acini on the basis of changes in cell hydration.

METHODS

Acini were exposed to hypotonicity or hypertonicity. The effects of corresponding changes in cell volume on various cell functions were analyzed.

RESULTS

Hypertonicity and hypotonicity caused a stepwise cell shrinkage and swelling, respectively. Cell shrinkage decreased and cell swelling increased amylase secretion stimulated by cholecystokinin (CCK) and carbachol but not by secretin. Changes in cell volume did not alter basal or CCK-stimulated calcium concentrations or CCK-stimulated inositol triphosphate generation. The regulation of secretion by cell volume is not mediated via changes in CCK receptor binding or protein kinase C. The increase of amylase release caused by hypotonicity was completely inhibited by cytochalasin B, colchicine, and genistein. Hypotonicity as well as CCK caused activation of mitogen-activated protein kinases.

CONCLUSIONS

Changes in cell volume regulate exocrine secretion of pancreatic acini. The effects were found only for secretagogues that act via the calcium/inositol-trisphosphate pathway. However, the mechanisms involved are located at luminal parts of the signal-transduction cascade and involve the cytoskeleton, protein phosphorylation, and activation of mitogen-activated protein kinases.

Refolding of a recombinant collagen-targeted TGF-beta2 fusion protein expressed in Escherichia coli

In this study, a tripartite transforming growth factor-beta (TGF-beta2) fusion protein bearing an N-terminal purification tag and an auxiliary collagen binding decapeptide has been constructed and expressed at high levels in Escherichia coli. The resulting recombinant protein accumulates in an insoluble and biologically inactive inclusion-body complex. The insoluble protein was solubilized in guanidine hydrochloride and a Ni-chelating affinity column was utilized to isolate the 13.5-kDa TGF-beta2 fusion protein, which was then refolded into its native conformation under controlled redox conditions. The formation of native homodimers was monitored by nonreducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis gradient gels and the bioactivity determined by a quantitative TGF-beta assay system using mink lung epithelial cells transfected with a plasminogen activator inhibitor-1 promoter/luciferase reporter plasmid. To optimize yields, renaturation conditions including denaturants, limiting protein concentrations, redox ratios, dialysis conditions, and refolding kinetics were studied and monitored by bioactivity. These studies demonstrate that recombinant TGF-beta2 fusion proteins can be produced in E. coli and renatured into biologically active homodimers. Furthermore, they confirm that the auxiliary collagen binding domain effectively targets the recombinant growth factor to type I collagen. Taken together, these studies advance the technology necessary to generate large quantities of targeted TGF-beta fusion proteins for specific biomedical applications.

Studies on Interaction of Dodecyltrimethylammonium Bromide with Na- and Al-Montmorillonite

The adsorption isotherms and adsorption enthalpies of dodecyltrimethylammonium bromide (DDTMAB) on Na- and Al-montmorillonite were determined in the pH range 2-12. The basal spacings of the clays were also studied by X-ray diffraction. Interactions of DDTMAB with the two montmorillonites predominate mostly through cation exchange in the pH range studied. In the case of Na-montmorillonite, the amount of adsorption increases with pH, but adsorption enthalpy decreases with pH. For Al-montmorillonite, adsorption enthalpy exhibits nonmonotonic variation with pH, although the amount of adsorption increases with pH monotonously. The adsorption enthalpies of DDTMAB on the clays are negative. The adsorbed DDTMAB molecules in clay interlayers present a bilayer arrangement at saturation. Copyright 1997 Academic Press. Copyright 1997Academic Press

Cytotoxicity of peroxynitrite in rat pancreatic acinar AR4-2J cells

Peroxynitrite (0.5-50 microM) induced dose-dependent cytotoxic effects in rat pancreatic acinar AR4-2J cells. Glutathione (2 mM) and ebselen (10 microM) partially reduced the cytotoxicity caused by 1-10 microM concentrations of peroxynitrite. Higher concentrations (10-50 microM) of peroxynitrite induced DNA smear suggestive of necrosis, while lower concentrations (2-5 microM) induced DNA fragmentations suggestive of apoptosis. The effects of peroxynitrite on [Ca2+]i showed a similar dose dependency. Peroxynitrite concentrations > 10 microM rapidly increased [Ca2+]i in a dose-dependent manner, while concentrations < 5 microM did not affect [Ca2+]i. In contrast, the presentation of wild-type P53 was accelerated at lower concentrations of peroxynitrite (< or = 10 microM) but not at higher concentrations (50 microM). The present study suggests that peroxynitrite at lower concentrations (2-5 microM) induces wildtype P53 and apoptosis, which is potentially a protective response toward the DNA damage caused by peroxynitrite. On the other hand, higher concentrations of peroxynitrite (10-50 microM) rapidly increase [Ca2+]i and eventually induce necrosis.

Capture and expansion of bone marrow-derived mesenchymal progenitor cells with a transforming growth factor-beta1-von Willebrand's factor fusion protein for retrovirus-mediated delivery of coagulation factor IX

Mesenchymal stem cells give rise to the progenitors of many differentiated phenotypes, including osteocytes, chrondocytes, myocytes, adipocytes, fibroblasts, and marrow stromal cells, which are capable of self-renewal and undergo expansion in the presence of transforming growth factor-beta1 (TGF-beta1). The present study was designed to test the concept that mesenchymal progenitor cells could be selected and expanded by virtue of their intrinsic physiologic responses to TGF-beta1. Human bone marrow aspirates were initially cultured, under low serum conditions, in collagen pads or gels impregnated with a genetically engineered TGF-beta1 fusion protein bearing an auxiliary von Willebrand's factor-derived collagen-binding domain (TGF-beta1-vWF). Histologic examination of TGF-beta1-vWF-supplemented collagen pads from 8-day cultures revealed the selective survival of a population of mononuclear blastoid cells. The TGF-beta-responsive cells were expanded to form stromal/fibroblastic colonies by serum reconstitution, and further to form osteogenic colonies upon supplementation with osteoinductive factors. In comparative studies, both marrow-derived progenitor cells and mature stromal cells were transduced with a retroviral vector bearing a human factor IX construct. Both the transduced progenitor cells and mature stromal cells expressed the factor IX transgene at levels comparable to those reported for human fibroblasts. Transplantation of murine progenitor cells bearing the human factor IX vector into syngeneic B6CBA mice resulted in detectable circulating levels of the human factor IX antigen. Taken together, these data demonstrate a novel physiologic approach for the selection of mesenchymal precursor cells followed by mitotic expansion, transduction, and transplantation of these progenitor cells with retroviral vectors bearing therapeutic genes.

Spontaneous duplication of a 661 bp element within a two-component sensor regulator gene causes phenotypic switching in colonies of Pseudomonas tolaasii, cause of brown blotch disease of mushrooms

Spontaneous sectoring of Pseudomonas tolaasii colonies results in a phenotypic switch from the smooth, pathogenic form (designated 1116S) to the rough non-pathogenic form (designated 1116R). This phenotypic switch can also be induced by mutation of the pheN master regulatory locus, which encodes a 99 kDa protein with homology to the conserved family of sensor regulator proteins. Southern blot analysis of genomic DNA from 1116S and 1116R probed with a 3.4 kb Xhol-BamHI fragment containing the pheN gene has revealed restriction fragment length polymorphisms in the pheN locus of 1116R. In order to characterize the genetic basis of this variation, the pheN locus (designated pheN') was cloned from 1116R and its nucleotide sequence determined. A 661 bp duplication was identified within pheN' introducing a frameshift mutation in the predicted pheN open reading frame (ORF). A resulting predicted ORF of pheN' designated ORF2 encodes a polypeptide of 706 amino acid residues, with a predicted molecular weight of 77 kDa, and which lacks part of the PheN sensor domain. Southern blot analysis of genomic DNA using a probe within the duplicated sequence revealed the presence of two bands in 1116R but only one band in the 1116S form. Polymerase chain reaction (PCR) analysis of 25 independently isolated 1116R sectors using primers flanking the duplication site in pheN confirmed the presence of the duplicated 661 bp sequence within this region in all of the sectors and the absence of the duplicated sequence in spontaneous revertants from 1116R to 1116S. Northern blot analysis of RNA from 1116S and 1116R using a pheN probe showed that ORF2 was transcribed in the 1116R form. The presence of a truncated PheN protein in 1116R was verified by Western blot analysis of total cell protein using a LemA antiserum, which revealed the presence of 99kDa and 77kDa cross-reactive bands in 1116S and 1116R respectively. It is concluded that the spontaneous colony-sectoring event that results in the 1116R phenotypic variant form of P. tolaasii arises owing to a 661 bp DNA duplication within the 5' end of the pheN gene, which results in loss of the periplasmic sensor domain of PheN and elimination of normal PheN function.

[Indocyanine green angiography in central serous chorioretinopathy]

OBJECTIVES

To know the results of indocyanine green angiography (ICGA) in central serous chorioretinopathy (CSC) and approach its pathogenetic mechanisms.

METHODS

20 cases of CSC were examined by scanning laser ophthalmoscope to perform blue laser beam examination, fundus fluorescein angiography (FFA) and indocyanine green angiography.

RESULTS

(1) The blue laser beam: The elevation lesions of the sensory retinal and retinal pigment epithelial detachment were clearly found. (2) ICGA: In the early phase, choroidal delayed filling (95.0%), choroidal hyper-perfusion (80.0%), choriocapillary dilatation, and in the late phase, hyperfluorescent spots (95.0%), diffuse choroidal hyperfluorescence (77.5%), abnormal fluorescence over vortex vein were found. (3) FFA demonstrated the hyperfluorescence of the choroidal background and the optic disc.

CONCLUSIONS

CSC patients have obvious choroidal circulatory disorder and the ICGA is a good method for the study of the pathogenetic mechanisms of the CSC and its therapeutic evaluation.

Enthalpy of Adsorption and Isotherms for Adsorption of Naphthenic Acid onto Clays

The enthalpies of adsorption and the isotherms for adsorption of naphthenic acid onto Na-montmorillonite, Na-kaolinite, and Na-illite were studied by means of calorimetry and the static method at 298.15 K. The results show that the enthalpies of adsorption and saturated adsorption amounts of naphthenic acid on different clays change in the order Na-montmorillonite > Na-illite > Na-kaolinite. The interaction between naphthenic acid and clays is discussed.

Factors which affect the calcification of tissue-derived bioprostheses

Mineralization of implanted bioprostheses poses a major clinical problem. Crosslinking of collagenous matrices, a process used to render tissues relatively inert and nonbiodegradable, seems to encourage calcification. Residual, noncovalently bound glutaraldehyde, as well as glutaraldehyde crosslinks which can be degraded with time, seem to play a role in this connection. Our findings demonstrate the need to carefully remove noncovalently or labile-associated glutaraldehyde by thorough rinsing or neutralization before implantation. Components of a valve prosthesis such as cusps and aortic wall, which are known to vary in their proportions of collagen, elastin, and noncollagenous proteins and to calcify to different extents, can both be prevented from calcifying if treated with a biphosphonate before implantation. Calcification can also be reduced by selective enzymatic removal of noncollagenous materials. In addition to the age of rats, animals usually used to evaluate calcification, the strain of animal can markedly affect the response. The Fischer-344 rat, a highly inbred animal, will not calcify exhaustively rinsed implants. Our findings suggest that multifactorial approaches may have to be combined to generate the most ideal bioprostheses. These should include careful removal of noncovalently bound glutaraldehyde, neutralization of the nonbifunctionally reacted residues, removal of lipids and noncollagenous proteins (and possibly the more antigenic nonhelical collagen telopeptides), as well as inclusion of agents such as biphosphohates, which by interfering with crystal growth prevent the accumulation of mineral in the interstices of the tissue.

Collagen content is significantly lower in restenotic versus nonrestenotic vessels after balloon angioplasty in the atherosclerotic rabbit model

BACKGROUND

It is recognized that restenosis is primarily due to alterations in geometric remodeling of the extracellular matrix rather than intimal hyperplasia. Prior studies have shown that angioplasty stimulates an increase in both synthesis and degradation of collagen in the atherosclerotic vessel. However, differences in collagen content and metabolism between restenotic and nonrestenotic vessels have not been examined.

METHODS AND RESULTS

Four weeks after angioplasty in an atherosclerotic rabbit model, collagen content in restenotic and nonrestenotic vessels was measured both biochemically by hydroxyproline quantitation and histologically by a digital subtraction method with the use of circularly polarized images of picrosirius red-stained sections. Collagenase and gelatinase activity also were measured in the same restenotic and nonrestenotic vessels by use of a radiosubstrate assay. Collagen content was found to be significantly lower in restenotic vessels than in nonrestenotic vessels both biochemically (127.0 +/- 32.6 versus 212.6 +/- 84.3 micrograms/mg tissue; n = 11 vessels; P < .05) and histologically (67.3 +/- 7.9% versus 76.3 +/- 11.8% area fraction; n = 20 sections from 6 vessels; P = .05). There was a significant inverse correlation between biochemically determined collagen content and gelatinase activity (P = .02) and a significant correlation between histologically determined lumen are and percent collagen content (P = .0071).

CONCLUSIONS

Collagen content is significantly decreased in restenotic versus nonrestenotic vessels after angioplasty in the atherosclerotic rabbit model. The increased collagen content in nonrestenotic vessels was associated with preserved lumen area and may play a role in geometric remodeling after angioplasty.

[The relationship between TIL from human primary hepatic carcinoma and prognosis]

OBJECTIVE

To determine whether tumor-infiltrating lymphocytes (TIL) could affect the prognosis for patients with primary hepatic carcinoma (PHC).

METHODS

Tissue distribution, proliferative property and cytotoxicity of TIL were measured in colour medical image analysis, immunohistochemical technique, 3H-thymidine proliferative response and LDH-release assay.

RESULTS

On the basis of infiltrating level of TIL, all patients with PHC were classified into three types in which there can be non-infiltrating, lower infiltrating and high infiltrating. The survival time of patients without TIL was shorter than that of patients with TIL. In addition, their postoperative intrahepatic recurrences were higher than those of the latter. Freshly isolated TIL showed more poor proliferation and cytotoxicity than autologous peripheral blood lymphocytes (PBL) in vitro. TIL activated with anti-CD3 McAb and rIL-2 displayed higher cytotoxicity against fresh autologous hepatic carcinoma cells than against K562 targets.

CONCLUSION

Clinically, TIL are associated with the prognosis for patients with PHC, however, it is in the tumor nest that the functions of TIL are impaired or suppressed by some factors locally produced by tumor cells in vivo.

Adsorption Enthalpy and Adsorption Isotherm of Tetradecylpyridinium Bromide on Na-Montmorillonite

The adsorption enthalpy and the adsorption isotherm of tetradecylpyridinium bromide (TPB) onto a Na-montmorillonite suspension and the dilution enthalpy of the TPB solution have been determined at 298.15 K. The dilution process is endothermic and the adsorption process is exothermic. For ion exchange adsorption, the interaction between TP+ and the montmorillonite is much stronger than that between Na+ and the montmorillonite because the cumulative adsorption enthalpy increases dramatically with adsorption amount. For molecular adsorption, however, the interaction between TPB and the clay is much weaker.

Menadione induces both necrosis and apoptosis in rat pancreatic acinar AR4-2J cells

This study evaluated the action of menadione on cell proliferation and integrity of the rat pancreatic acinar cell line, AR4-2J. Menadione at 1-20 microM dose- and time-dependently inhibited cell proliferation of AR4-2J cells. In contrast, a high concentration of menadione (100 microM) caused rapid cell death (> 90% of cells took up trypan blue within 4-h). While the high concentration of menadione (100 microM) induced DNA smear in electrophoresis indicative of necrosis, lower concentrations (10-20 microM) induced a DNA ladder indicative of apoptosis. Similar results were obtained using a DNA fragmentation ELISA. Glutathione (1 mM), the calcium chelator EGTA (500 microM), and the cysteine protease inhibitor NCO-700 (5 mM) partly inhibited the effect of 1-10 microM menadione on cell proliferation and DNA fragmentation. Menadione at 1-20 microM induced wild-type P53, whereas the 100 microM menadione had a minor effect on wild-type P53. It is concluded that menadione induced necrosis at high concentrations and apoptosis at low concentrations in AR4-2J cells. Apoptosis induced by lower concentrations of menadione may be mediated by wild-type P53, intracellular calcium, and mechanisms which decrease the intracellular concentration of reduced glutathione.

Changes in late-embryogenesis-abundant (LEA) messenger RNAs and dehydrins during maturation and premature drying of Ricinus communis L. seeds

In Ricinus communis L. (castor bean) endosperms, two classes of Late Embryogenesis Abundant (Lea) transcripts were first detected during mid-development (at 30-35 days after pollination, DAP) and peaked at 50 DAP, just prior to the onset of desiccation. Most of the Class I mRNAs declined substantially during desiccation itself; Class II mRNAs remained abundant in the mature dry (60 DAP) seed. Following imbibition, all Lea mRNAs abundant in the mature dry seed declined rapidly (within 5-24 h). Premature drying of developing 35-DAP seeds resulted in the loss of storage-protein mRNAs (Leg B Mat I); following rehydration, mRNAs encoding post-germinative proteins (Germ D91, D30 and D38) increased in the endosperm. The Lea mRNAs present in the developing fresh seed at 35 DAP were preserved, but did not increase in response to premature desiccation; upon rehydration these Lea mRNAs declined within 5 h. During seed development, substantial changes occurred in the synthesis of a subset of LEA proteins referred to as "dehydrins'; in particular, new dehydrin polypeptides were induced between 40 and 60 DAP. Such proteins were not as evident in prematurely dried endosperms. In contrast to the rapid loss of Lea mRNAs during germination, many of the dehydrin proteins abundant in the dried seed persisted following imbibition or rehydration.

Developmental patterns of aluminum and five essential mineral elements in the central nervous system of the fetal and infant guinea pig

Al is found in the developing conceptus, but little information is available concerning its tissue distribution and its changes in concentration with age. Because Al has affinity for many of the same biological ligands as the essential mineral cations Ca, Mg, Zn, Fe, and Mn, we hypothesized that Al might show a pattern of developmental concentrations that was similar to one or more of these elements in the brain, a major target of Al toxicity. Concentrations of Al, Ca, Mg, Zn, Fe, and Mn were measured in spinal cord, brainstem, cerebellum, and forebrain of guinea pig fetuses on gestation day (GD) 30 and 45, at birth, and on postnatal day (PND) 3, 6, and 12. Dams were fed commercial guinea pig chow, which contained 47 micrograms Al/g. Tissue Al and Mn were measured with electrothermal atomic absorption spectrophotometry (ETAAS), and the other elements with inductively coupled axial plasma spectroscopy (ICAP-AES). Al concentrations in the brain regions were highest in spinal cord, brainstem, and cerebellum, and decreased during late gestation and lactation. Al did not show marked increases in regional brain concentrations during the final third of gestation as did Fe, Mg, and Zn. In contrast to Fe and Ca, Al did not accumulate in placenta. Al was the only element to show higher concentrations in spinal cord than in any other tissue at birth. In summary, the tissue distribution of Al did not follow that of essential cations as examined in this study.

[Changes of Kupffer cell DNA and RNA synthetic functions after partial hepatectomy in cirrhotic rats]

We studied the changes of DNA and RNA synthetic functions of regenerating liver cells after partial hepatectomy in cirrhotic rats and discussed the relationship between liver regeneration and liver functional failure. Seventy healthy male Wistar rats weighing 200 approximately 250 g, were randomized into sham-operated (SO), partial hepatectomy in cirrhotic rats (C-PH) and partial hepatectomy in normal rats (N-PH). The left and middle lobes were dissected. The synthetic DNA peak of Kupffer cells (KC) in the G2 and M phase in C-PH was found after 24 hr of operation. The regenerating index peak of KC was at 48 hr after operation, which was higher than the other groups, but the liver weights in C-PH was lower than that in the N-PH at 1 week after operation. The RNA content of KC markedly decreased and returned to normal levels at 1 week after operation. We think that KC functions are suppressed after partial hepatectomy in cirrhotic rats. It is an important cause of hepatocyte regeneration function decrease and liver functional failure for delay of liver cell regeneration "start" and the regeneration cell cycle.

[The role of urokinase type plasminogen activator in invasion of bile duct carcinoma]

OBJECTIVE

To study the role of urokinase type plasminogen activator (u-PA) in the invasive process of bile duct carcinoma.

METHODS

The secretion of u-PA and the invasive potential of tumor cell in vitro in a newly established cell line of bile duct carcinoma, QBC939, were observed by using an amnion invasion culture system.

RESULTS

QBC939 cells secreted u-PA with high invasive potential. The inhibitors of u-PA and plasmin, tranexamic acid and 6-aminocaproic acid, obviously inhibited the u-PA activity and the invasive potential of QBC939 cells.

CONCLUSION

u-PA is one of the important enzymes in tumor invasion. Inhibiting u-PA or plasmin may be a prospective therapy for tumor treatment.

[Effects of high salt-loading on the regulation of angiotensin II receptor mRNA expression]

In the present study, the angiotensin II receptor subtype I-a (AT1a) and I-b (AT1b) mRNA levels in aortic smooth muscle (ASM), ventricular myocardium (VM) and adrenal from 12-week-old stroke-prone spontaneously hypertensive rats (SHRsp) and age-matched Wistar-Kyoto (WKY) rats with normal diet (control) and high salt-loading were examined by reverse transcriptase-polymerase chain reaction (RT-PCR). The results showed that: (1) The AT1a and AT1b mRNA levels in ASM and VM from SHRsp were lower than those from WKY rats (in ASM, 10% and 23%, while in VM, 23% and 40% lower, respectively). In contrast, both AT1a and AT1b mRNA levels in adrenal from SHRsp were higher (176% and 157%, respectively). (2) In the WKY rats with high salt-loading, the AT1a and AT1b mRNA levels in adrenal, as well as AT1b mRNA level in VM, increased significantly, as compared with the control (in adrenal, 167% and 401%, while in VM, 62%). However, the AT1a and AT1b mRNA levels in ASM, as well as AT1a mRNA level in VM, showed no obvious change. (3) In SHRsp with high salt-loading, the AT1b mRNA level in ASM, as well as AT1a and AT1b mRNA levels in VM, increased markedly (in ASM, 90%, while in VM, 590% and 200%); whereas the AT1a mRNA level in adrenal decreased significantly (58%). There was little influence on the regulation of AT1a (in ASM) and AT1b (in adrenal) receptor gene expression after high salt-loading. The results suggest that AT1a and AT1b receptors may be involved in the pathogenesis of salt-induced hypertension. The up-regulation of AT1b receptors in ASM may induce the remodeling of arterial wall, while that of AT1a and AT1b receptors in VM might contribute to ventricular hypertrophy in hypertension. Furthermore, there are certain differences between SHRsp and WKY rats with respect to the regulation of AT1a and AT1b receptor gene expression with or without external stimulation.

[Pathological study on the metastatic routes of bile duct carcinoma]

Multiple staining was performed on resected tumors. Samples after curative surgery in 40 cases of bile duct carcinoma for observation of tumor blood vessel density (TVD), and perineural invasion index (PNI). Lymphatic invasion was found in 29 cases (72.5%), blood vessel invasion in 31 (77.5%), and PNI in 33 (82.5%). TVD and PNI were positively correlated with metastasis. Three years after operation, the recurrent rate was 100%, with an averaging recurrent time of 9.6 months in the metastatic group in contrast to 64.3% and 17.5 months in those without metastasis.

Iron and manganese uptake by offspring of lactating mice fed a high aluminum diet

High dietary A1 can result in lowered tissue Mn and Fe concentrations in weanling mice. Possible mechanisms underlying this effect of A1 (altered milk Fe and Mn content, altered absorption or retention of Fe and Mn) were investigated in this experiment. To determine if milk composition was changed, milk was analyzed for Fe and Mn at 0, 3, 7, and 12 days postnatal. To determine if A1 influenced absorption and/or retention of Fe and Mn, a single milk meal containing 54Mn and 59Fe was administered by gavage to 12 day old pups and tissues were obtained 6 and 24 h later. Pup body and tissue weights were not affected by the high A1 diet. Milk from dams fed high A1 diets (1000 micrograms A1/g, n = 11, A11000) had similar Fe and Mn concentrations as milk from dams fed a control diet (7 micrograms A1/g, n = 11), although A1 concentrations were higher. Absorption and tissue distribution of 54Mn and 59Fe, as determined at the 6 h timepoint, were unaffected by maternal diet group (control n = 16, AL1000 n = 10). However, total retention of both 54Mn and 59Fe was 8-10% lower in the AL1000 pups 24 h after gavage (P = 0.030 for Mn and 0.017 for Fe). These data suggest that high dietary A1 during development alters the ability of nursing mouse pups to retain absorbed Fe and Mn.

Aluminum alters iron and manganese uptake and regulation of surface transferrin receptors in primary rat oligodendrocyte cultures

Transferrin (Tf) is a major transport protein for both iron (Fe) and aluminum (Al), as well as manganese (Mn) and it can mediate cellular uptake of these elements via cell surface Tf receptors. To study the effect of Al-Tf on Tf receptor regulation, primary oligodendrocyte cultures were prepared from cortices of newborn rats. The effects of Al-Tf on 54Mn and 59Fe uptake were compared to those of apo-, Fe-, or Mn-Tf (1.25 microM). To examine changes in cell surface Tf binding capacity, preincubation (4 h, 37 degrees C) was performed with apo-, Al- or Fe-Tf and homologous receptor binding studies were subsequently conducted with 125I-Fe-Tf at 4 degrees C. Incubation with Al-Tf, but not with equimolar amounts of Al chloride or Al citrate, led to dose-related increases in cellular Al. Incubation with either Al- or Fe-Tf decreased 59Fe uptake, while incubation with either Al- or Mn-Tf decreased 54Mn uptake. Surface Tf receptor sites/cell were 1.05, 0.60 and 0.46 x 10(5) after incubations with equivalent amounts of apo-, Fe-, and Al-Tf respectively. The data suggest that Al-Tf down-regulates surface Tf receptors on oligodendrocytes and can limit Fe and Mn uptake through this mechanism.

Balloon angioplasty significantly increases collagen content but does not alter collagen subtype I/III ratios in the atherosclerotic rabbit iliac model

Angioplasty has been reported to increase collagen content and to alter vascular collagen alpha 1(I), alpha 2(I), and alpha 1(III) mRNA levels. Collagen synthesis is tightly regulated by complex translational and post-translational mechanisms such that mRNA levels may not necessarily reflect biosynthesis. To test whether collagen subtype I and III protein levels are altered by angioplasty, we quantitatively analysed collagen I/III protein ratios at 4 weeks after balloon angioplasty. Twenty New Zealand White rabbits underwent iliac artery balloon de-endothelialization and then were placed on a 0.5% cholesterol/6% peanut oil diet for 7 weeks at which time angioplasty was performed on arteries with > or = 50% stenosis. Arteries with < 50% stenosis were not dilated and served as controls. Animals were killed 4 weeks later and hydroxyproline (OH-pro) content and subtype I/III ratios were analysed in 5-mm mid-iliac sections. OH-pro was measured by a colorimetric assay. Subtype ratios were determined by a highly quantitative two-dimensional cyanogen bromide peptide mapping method. The degree of stenosis was measured as the minimal vessel lumen diameter and calculated as a percentage stenosis compared to a proximal reference segment. Calculated collagen content (micrograms/mg tissue) was significantly higher 4 weeks following angioplasty compared to the non-dilated group (220.4 +/- 70.8 v 308.2 +/- 26.9, P = 0.04; n = 12), despite similar percentage stenosis in the primary and restenotic lesions. The ratio of collagen I/III subtype protein distribution was not significantly different in the non-dilated and angioplastied groups (4.88 +/- 1.00 v 4.70 +/- 0.82, respectively). These studies are the first to provide data on collagen I/III subtypes following angioplasty and suggest that collagen accumulation may be more important in restenosis than alteration of collagen protein subtypes.

Engineering, expression and renaturation of targeted TGF-beta fusion proteins

This study reports the expression, purification, and renaturation of biologically active Transforming Growth Factor-beta 1 (TGF-beta 1) fusion proteins from Escherichia coli (E. coli). A prokaryotic expression vector was engineered to produce tripartite fusion proteins consisting of (i) a purification tag, (ii) a protease-sensitive linker/collagen binding domain, and (iii) a cDNA sequence encoding the active fragment of human TGF-beta 1. The expressed fusion proteins TGF-B1-F1 and TGF-B1-F2, located in inclusion bodies, were solubilized with 8 M urea and renatured using a glutathione redox-coupled system and protracted dialysis under several experimental conditions. The purification of the recombinant proteins was achieved by binding the His-tag of the fusion proteins on a Ni-NTA metal chelate column. The biological activity of the recombinant growth factor was demonstrated by its ability to inhibit mink lung (Mv1Lu) cell proliferation and/or to stimulate proliferation of NIH-3T3 mouse fibroblasts, where purified human platelet TGF-beta 1 served as a positive control. Purified TGF-B1-F1 and TGF-B1-F2 (collagen-binding) constructs exhibited anti-proliferative activities comparable to purified platelet TGF-beta 1, but at lower specific activities. Binding of the renatured TGF-B1-F2 fusion protein to collagen was demonstrated by stable binding on a collagen-conjugated Sephadex-G15 column. The high affinity binding was also demonstrated by the binding of 3H-collagen to the TGF-B1-F2 protein immobilized on a Ni-NTA column. The TGF-B1-F2 fusion protein bound to collagen coated surfaces with high affinity but exhibited comparatively lower biological activity than the fusion protein in solution, suggesting a potentially latent configuration. Taken together, these results demonstrate that biologically active TGF-beta 1 fusion proteins can be recovered from transformed bacteria by oxidative refolding; thus, providing a means for its high-yield production, purification, and renaturation from microorganisms. Furthermore, these results support the concept that auxiliary domains may be used to modulate and/or target TGF-beta 1 for specific applications.

Importance of extracellular domains for ligand binding in the thyrotropin-releasing hormone receptor

The role of putative extracellular sequences for ligand binding in the TRH receptor was examined using deletion or substitution mutations. Each mutant receptor was transiently expressed in TRH receptor-minus GH(1)2C(1)b rat pituitary cells, and binding of 4 Nu Mu [3H]pGlu-N(tau)-MeHis-Pro-NH2 ([3H] MeTRH) was measured. When binding was not detected, signal transduction at 10 microM MeTRH was measured to assess receptor expression. Deletion of most of the N-terminal sequences (Glu(2)-Leu(22)), including two potential glycosylation sites, had no effect on the affinity of the receptor for MeTRH. Segmental deletions or simultaneous substitution of multiple amino acid residues in the first, second, or third extracellular loop (EL1, EL2, or EL3) resulted, however, in total loss of [3H]MeTRH binding, suggesting important roles for the loop sequences in either receptor expression or ligand binding. Individual substitutions were made to test further the role of the specific extracellular loop sequences in TRH binding. In EL1, conversion of Tyr93 to Ala resulted in more than 20-fold decrease in affinity for MeTRH. In EL2 and the top portion of the fifth transmembrane helix, conversion of Tyr181 to Phe, Tyr188 to Ala, and Phe199 to Ala resulted in a large ( > 100-fold) decrease in affinity for MeTRH, and conversion of Tyr 188 to Phe and Phe196 to Ala caused an agonist-specific 4- to 5-fold decrease in affinity. In EL3, conversion of Asn289 to Ala and of Ser290 to Ala caused a large ( > 100-fold) decrease in affinity for MeTRH. These results suggest important roles for the extracellular loops in high affinity TRH binding and lead us to propose a model in which TRH binds to the extra-cellular domain of its receptor.

A canine model for determination of the therapeutic index of cytokine inhibitors

Using tumor necrosis factor (TNF) inhibition in dog blood as a measure of efficacy, and canine emesis as a measure of toxicity, we were able to assign a therapeutic index to rolipram, a prototypic anti-inflammatory compound. Because both assays were performed in the same species, the ambiguities associated with comparing the physiologic effects of drugs on various species was avoided. Rolipram, a standard phosphodiesterase type IV inhibitor, was a prototypic test compound characterized by a number of cardiovascular and central nervous system side effects, as well as its in vitro and in vivo inhibition of TNF. Initial experiments with canine whole blood incubated with lipopolysaccharide resulted in nanogram-per-milliliter concentrations of TNF that could be significantly reduced by in vitro addition of a 0.03 microM concentration of rolipram. Because rolipram inhibited canine TNF production in vitro, a protocol was devised in which TNF inhibitory activity was measured in a series of blood samples from dogs infused with increasingly high doses of rolipram. This yielded the efficacy half of the therapeutic index, whereas the emetogenic dose represented the side effect portion of the index. Rolipram was infused stepwise into conscious dogs at gradually increasing doses. The infusion was stopped when vomiting occurred, and the cumulative dose was reported as the emetic dose. Rolipram caused emesis in dogs at a cumulative dose of 0.1 mg/kg. At each dose of rolipram, blood was collected. The whole blood was incubated in vitro with lipopolysaccharide to induce TNF production, which in turn was quantified by the L929 bio-assay. Theoretically, if the rolipram infusion raised blood values high enough, the rolipram in whole blood would inhibit TNF production and be reflected by a lack of TNF activity in the L929 assay. In this assay system, rolipram's 50% effective dose in the TNF assay was always at least 33-fold lower than its emetic dose of 0.1 mg/kg. This gave rolipram a therapeutic index of at least 33:1 (0.003 versus 0.1 mg/kg) on the basis of its activity in a canine efficacy model (TNF inhibition) and a toxicity model (emesis induction). Experimental compounds were tested for their emetic dose as well as TNF 50% effective dose, with the goal of obtaining a therapeutic index better than that of rolipram. Thus the coupling of cytokine activity with overt toxicity was used to arrive at the therapeutic index of a compound. The therapeutic index was used to rank compounds as to their efficacy/toxicity profile. This ranking was used to eliminate several anti-inflammatory compounds that had a therapeutic index less than that of rolipram.

[Role of type IV collagenase in tumor cell invasion and effect of laminin on invasive potential in bile duct carcinoma]

In the present experiment, the secretion of type IV collagenase, the invasive potential of tumor cell in vitro, and the effects of exogenous laminiu and anti-laminin antibody on the invasive potential of tumor cells in a newly established cell line of bile duct carcinoma, QBC939, were observed by using an amnion invasion culture system and a substrate capture immunoassay. The biological mechanism of tumor invasion, especially the role of the type IV collagenase in the invasive process, was discussed. QBC939 cells secreted type IV collagenase with high invasive potential. Different doses of laminin (1 micrograms, 5 microgram, 10 microgram/ml) stimulated the release of type IV collagenase and increased the invasive potential of the tumor cells in varying degrees. The effect of laminin could be antagonized by the anti-laminin antibody. The results demonstrate that the type IV collagenase is one of the important enzymes involved in the tumor invasion. The effects of laminin on the release of type IV collagenase and the invasive potential suggest that laminin play an important role in mediation of tumor invasion. The results also suggest that inhibiting type IV collagenase or blocking the effect of laminin on tumor cells may be a prospective therapy for tumor treatment in future.

Identification of Asn289 as a ligand binding site in the rat thyrotropin-releasing hormone (THR) receptor as determined by complementary modifications in the ligand and receptor: a new model for THR binding

To test the hypothesis that pGlu of the thyrotropin-releasing hormone (TRH, pGlu-His-ProNH2) binds to Asn289 in the third extracellular loop (EL3) of its receptor through a hydrogen bonding interaction, we converted Asn289 to Asp (N289D mutant) and measured the potencies of TRH and Pro1TRH for the wild-type and mutant receptors. TRH was 100 times less potent for the N289D receptor than for the wild-type. In contrast, Pro1TRH, which has a protonated proline in place of the pGlu of TRH, was 10 times more potent for the N289D receptor than for the wild-type. A similar result was obtained when Asn289 was converted to Glu, while the potency of Pro1TRH did not change when Asn289 was converted to Ala, confirming that the increased potency of Pro1TRH for the N289D receptor was due to a charge interaction between Pro1TRH and the mutant receptor. These findings are inconsistent with a previous model indicating a direct interaction of the pGlu of TRH with Asn110 in the third transmembrane helix of the receptor (Perlman et al. (1994) J. Biol. Chem. 269, 23383-23386). When Asn110 was converted to Asp (N110D mutant), unlike the N289D receptor, the potency of Pro1TRH for the N110D receptor was decreased by > 10-fold rather than increased. Therefore, a direct interaction of Asn110 with the pGlu of TRH could not be supported by our experiments. We propose a new model in which the pGlu of TRH binds to Asn289 in EL3 and conclude that, unlike catecholamines which bind completely within the transmembrane domain of their receptors, this tripeptide binds, at least in part, to the extracellular domain of its receptor.

Identification and characterization of a locus which regulates multiple functions in Pseudomonas tolaasii, the cause of brown blotch disease of Agaricus bisporus

Pseudomonas tolaasii, the causal agent of brown blotch disease of Agaricus bisporus, spontaneously gives rise to morphologically distinct stable sectors, referred to as the phenotypic variant form, at the margins of the wild-type colonies. The phenotypic variant form is nonpathogenic and differs from the wild type in a range of biochemical and physiological characteristics. A genomic cosmid clone (pSISG29) from a wild-type P. tolaasii library was shown to be capable of restoring a range of characteristics of the phenotypic variant to those of the wild-type form, when present in trans. Subcloning and saturation mutagenesis analysis with Tn5lacZ localized a 3.0-kb region from pSISG29, designated the pheN locus, required for complementation of the phenotypic variant to the wild-type form. Marker exchange of the Tn5lacZ-mutagenized copy of the pheN locus into the wild-type strain demonstrated that a functional copy of the pheN gene is required to maintain the wild-type pathogenic phenotype and that loss of the pheN gene or its function results in conversion of the wild-type form to the phenotypic variant form. The pheN locus contained a 2,727-bp open reading frame encoding an 83-kDa protein. The predicted amino acid sequence of the PheN protein showed homology to the sensor and regulator domains of the conserved family of two component bacterial sensor regulator proteins. Southern hybridization analysis of pheN genes from the wild type and the phenotypic variant form revealed that DNA rearrangement occurs within the pheN locus during phenotypic variation. Analysis of pheN expression with a pheN::lacZ fusion demonstrated that expression is regulated by environmental factors. These results are related to a model for control for phenotypic variation in P. tolaasii.

Behavioral performance of Swiss Webster mice exposed to excess dietary aluminum during development or during development and as adults

Swiss Webster mice were exposed to excess dietary aluminum (500 or 1000 micrograms Al/g as Al lactate) from conception until weaning or from conception through adulthood (pre- and postweaning). Controls were fed a 7 micrograms Al/g diet. Excess Al diets did not influence pregnancy outcome, pup mortality, and body or organ weights. Al diets of 1000 micrograms/g led to enhanced cagemate aggression in offspring as adults. At 50 days of age, mice were trained for operant tasks and subsequently 35 sessions of delayed spatial alternation or discrimination reversal testing were conducted. Both the 500 and the 1000 micrograms Al/g diets led to faster attainment of criterion during the training phase of the operant studies, but did not influence performance of the two tasks. At the conclusion of the study (150-170 days of age), neurobehavioral measures and tissue trace metals (Al, Fe, Mn) were determined. Both the 500 and the 1000 micrograms Al/g diets led to reduced grip strength and the 1000 micrograms Al/g diet was associated with lower Fe concentrations in brain and spinal cord. Brain, spinal cord, and liver Al concentrations were elevated only in adults with continued exposure after weaning. Throughout the experiment, mice exposed before and after weaning were apparently no more affected on behavioral measures than those exposed only until weaning. It is concluded that developmental exposure to 500 and the 1000 micrograms Al/g diets had distinctive long-term effects on behavioral measures that were not dose dependent and were not further intensified by continuing exposure as adults.

[Adoptive immunotherapy of malignant pleural effusion with TIL/rIL2 (tumor-infiltrating lymphocytes/recombinant interleukin 2)]

TIL of 24 patients with malignant pleural effusions were induced and expanded in vitro. The phenotype of lymphocytes IL2R, NK cytotoxicity activity were analysed in fresh and activated TIL. CEA and cytology of malignant pleural effusion were detected before and after treatment with TIL/rIL2. The results indicated: CD4.CD8.IL2R, NK activity increased markedly, CEA level decreased in all of the patients, tumor cells disappeared in some patients. The pleural effusion disappeared in 63%. The total effective rate of the treatment is 79%. No serious toxicity and side effects were found in 1 to 6 months period of following-up after treatment.

Agonist-independent, muscle-type-specific signal transduction pathways in cat esophageal and lower esophageal sphincter circular smooth muscle

Smooth muscle cells isolated from the circular muscle layer of cat esophagus and lower esophageal sphincter (LES) exhibit distinct contractile intracellular signal transduction pathways in response to acetylcholine. To determine whether these contractile pathways are muscle type dependent, the authors examined the signal transduction pathways utilized by substance P and bombesin, which in other tissues, use different signal transduction pathways, and by the GTP analog, guanosine 5'-O-3-thiotriphosphate (GTP gamma S), which activates all available G proteins. Western blot analysis of esophageal and LES circular muscle revealed the presence of Gq-G11 (42 kD), Gi1-Gi2 (40 kD) and Go-Gi3 (40 kD) types of G proteins. The responses of esophageal cells to bombesin and substance P were blocked by 1) a Gi3 protein antibody, 2) the inhibitor of specific phosphatidylcholine-phospholipase C (PLC) D609 potassium tricyclo-[5.2.1.0(2.6)]-decyl-(9[8])-xanthogenate, 3) inhibition of phosphatidic acid phosphohydrolase by propranolol, 4) the protein kinase C inhibitor 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H7) and 5) incubation in Ca(++)-free medium. Conversely, the responses of LES muscle cells to bombesin and substance P were blocked by 1) a Gq-G11 antibody, 2) a phosphatidylinositol-specific PLC antagonist U-73122 (1-[6-[[17 beta-3-methoxyestra-1,3,5(10)-trien-17- yl]amino]hexyl]-1H-pyrrole-2,5-dione), 3) the calmodulin inhibitor CGS9343B (1,3-Dihydro-1-[1-((4-methyl-4H,6H-pyrrolo[1,2-a]-[4,1]benzoxazepin++ +-4 - yl)methyl-4-piperindinyl]-2H-benzimidazol-2-one maleate) and 4) incubation in Sr++. After permeabilization by saponin, inositol 1,4,5-trisphosphate contracted LES but not esophageal cells. The inositol 1,4,5-trisphosphate receptor antagonist heparin and depletion of intracellular Ca++ stores by thapsigargin or A23187 4-Benzoxazolecarboxylic acid, 5-(methylamino)-2-[[3,9,11-trimethyl-8-[1-methyl-2-oxo-2-(1H-pyrrol- 2-yl)ethyl]-1,7-dioxaspiro[5.5]undec-2-yl]methyl]-, [6s-[6.alpha. (2S*,3S*),8.beta. (R*), 9.beta., 11. alpha.]]-(9Cl), blocked bombesin- and substance P-induced contraction of LES but not of esophageal muscle. In addition, contraction in response to GTP gamma S, which activates all G proteins, was blocked in esophageal cells by a Gi3-protein antibody, propranolol, D609 and H7. In LES muscle cells, the response to GTP gamma S was blocked by a Gq protein antibody, U-73122 and CGS934B. These data demonstrate that, in esophageal muscle, different agonists activate the same Gi3 protein, phosphatidylcholine-specific phospholipases and protein kinase C-dependent pathway.(ABSTRACT TRUNCATED AT 400 WORDS)

Kinetics and reversibility of thyrotropin-releasing hormone-stimulated guanine nucleotide exchange in membranes from GH4C1 cells

To evaluate the role of thyrotropin-releasing hormone (TRH)-stimulated guanine nucleotide exchange in the biphasic cellular responses to TRH, we have examined the kinetics, reversibility, and inhibition by QC120 (an antiserum recognizing the carboxyl terminus of alpha q/11) of TRH-stimulated guanosine-5'-(alpha-[35S] thio)triphosphate ([35S]GTP alpha S) binding in membranes from GH4C1 cells. Enhanced binding of [35S]GTP alpha S stimulated by TRH was dose dependent and readily detectable within 8 sec of TRH treatment. Binding measured within the first 20 sec was largely inhibited by QC120, whereas additional binding that accumulated during incubations of 3-6 min was not inhibited by even high concentrations of the antiserum. TRH-stimulated binding was reversible, in that, after membranes were incubated with TRH and [35S]GTP alpha S, subsequent addition of excess GTP caused exchange of 70-100% of the prebound radioligand. Exchange of TRH-stimulated [35S]GTP alpha S binding occurred in fast and slow phases, with half-times of < 5 sec and 187 sec, respectively. Addition of QC120 before the GTP chase inhibited the fast phase of exchange, whereas reduction of the TRH concentration in the preincubation selectively reduced the magnitude of the slow phase. Neither phase of exchange was affected by prior treatment of cells with pertussis toxin. Our observations indicate that Gq/11 is rapidly activated by the TRH receptor and that a second, unidentified, G protein is slowly activated by the TRH receptor.

Auditory startle in Swiss Webster mice fed excess aluminum in diet

Using an automated method, reduced auditory startle responsiveness was detected in Swiss Webster mice fed excess aluminum in diet (1000 micrograms Al/g) as compared to controls (7 micrograms Al/g). Excess aluminum diets were fed either from conception to weaning (developmental group) or from conception and continuing to 52 days of age (continuous group). At 22 days of age, lower response amplitudes were seen in the aluminum exposed groups than in controls. At 52 days of age, more rapid reduction in response amplitude across initial trial blocks was noted. Effects were more prominent in the continuously exposed than the developmentally exposed group at 52 days of age. Reduced auditory startle responsiveness is interpreted as part of a pattern of subtle motor impairment and marginally reduced activity and responsiveness in mice fed excess aluminum in diet.