[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.

Intramuscular selenium administration in selenium-deficient cattle

Nine recently weaned Hereford heifers were randomly assigned to a control group (n = 3) or a treatment group (n = 6). The animals were selenium (Se) deficient (mean +/- SD blood Se concentration = 0.024 +/- 0.012 microgram/mL). They were maintained on a selenium-deficient diet, and on day 0 of the study the treatment group was given 0.05 mg Se/kg body weight intramuscularly, while the control group received a placebo. The Se concentration of blood, serum, and urine as well as the glutathione peroxidase (GSH-Px) activity of blood and serum was measured over an 84-day period. Peak blood Se and serum Se concentrations (mean +/- SD) in the treatment group occurred at 5 hours postinjection and were 0.131 +/- 0.028 microgram/mL and 0.154 +/- 0.027 microgram/mL, respectively. The mean blood Se concentration of the treatment group was greater (P < .05) than that of the control group for the first 28 days after injection. The mean serum Se concentration of the treatment group was greater (P < .05) than that of the control group for all times after injection, except for day 56. The mean (+/- SD) blood GSH-Px activity of the treatment group (12.0 +/- 2.3 mU/min/mg hemoglobin) was increased (P < .05) over the control group (2.0 +/- 1.4 mU/min/mg hemoglobin) by day 28 and continued to be greater (P < .05) throughout the 84 day postinjection period.(ABSTRACT TRUNCATED AT 250 WORDS)

Aluminum accumulation and neurotoxicity in Swiss-Webster mice after long-term dietary exposure to aluminum and citrate

The present study was performed to determine aluminum uptake, retention, and neurotoxic effects in the presence of dietary citrate. Six-week-old female Swiss-Webster mice were fed semipurified diets containing 3.5% sodium citrate and either 3 micrograms Al/g diet (3 Al) or 1,000 micrograms Al/g diet (1,000 Al) as AlCl3. After 5 to 7 weeks of feeding these diets, changes in behavior were assessed using the National Institute of Environmental Health Sciences Neurobehavioral Test Battery. Liver and bone Al concentrations in the 1,000 Al group were higher than in the 3 Al group at both the 5- and 7-week time points. Spinal cord Al concentrations in the 1,000 Al group were 200% higher at 5 weeks (P < .01) than in controls, and brain nuclear fraction Al concentrations in the 1,000 Al group were 150% higher at 5 and 7 weeks (P < .01) than in the 3 Al group. The Neurobehavioral Test Battery showed lower grip strength and greater startle responsiveness in the 1,000 Al group compared with the 3 Al group at both the 5- and 7-week time points. Based on reports that Al can act as a pro-oxidant, we examined Al-induced brain lipid and protein oxidative damage; neither was evident in the Al-intoxicated mice. In summary, feeding of Al and citrate to mice resulted in Al accumulation in the central nervous system, and this accumulation was associated with overt signs of neurotoxicity. Brain protein and lipid oxidative damage was not associated with early manifestation of Al toxicity.

Interferometric methods with enhanced sensitivity by optical/digital fringe multiplication

The equations of the optical/digital fringe multiplication method are derived for a general periodic distribution of intensity versus phase (or fringe order). The method is demonstrated by a shadow moiré experiment, which ideally produces fringe patterns with a triangular intensity distribution. Advantages and disadvantages of the optical/digital fringe multiplication method are discussed in comparison with other image-processing methods.

Developmental patterns of aluminum in mouse brain and effects of dietary aluminum excess on manganese deficiency

Previous studies have shown that excess dietary Al during development can affect neurobehavioral measures and decrease tissue Mn of 21-day-old weanling mice without a corresponding increase in tissue Al concentrations. Al and Mn have similar tissue concentrations and similar affinities for transferrin, which is the major plasma transport protein for Al and Mn as well as Fe. In the present study, brain Al, Mn and Fe were studied at 6, 12, 18 and 24 days of age in offspring of Swiss Webster mice fed a semipurified diet containing excess Al (Al[+], 1000 micrograms Al/g diet, Al as Al lactate), marginal Mn (Mn[-], 3 micrograms Mn/g diet) or both excess Al and marginal Mn (Al[+]Mn[-]) from conception to day 24 postnatal (weaning on day 18). Brain Al concentrations were higher at 6 days of age than at later ages and were significantly elevated by the excess Al diet (P = 0.017) but returned to control levels by weaning. Brain Mn concentrations increased from day 6 to day 24 and were lower in the Mn deficient groups (P < 0.001) and also in the excess Al group (P = 0.024) than in controls. Brain Fe concentrations were not influenced by diet. Similar patterns were seen in liver as in brain. The marginal Mn diet led to postnatal growth retardation which was more severe in litters of dams fed Al[+]Mn[-] diets than in litters fed Mn[-] diet. These data suggest that excess Al in diet can interact specifically with Mn metabolism during development.

Regional differences in retinoid release from embryonic neural tissue detected by an in vitro reporter assay

Retinoic acid and related retinoids have been suggested to contribute to the pattern of cell differentiation during vertebrate embryonic development. To identify cell groups that release morphogenetically active retinoids, we have developed a reporter assay that makes use of a retinoic acid inducible response element (RARE) to drive lacZ or luciferase reporter genes in stably transfected cell lines. This reporter gene assay allows detection of retinoids released from embryonic tissues over a range equivalent to that induced by femtomole amounts of retinoic acid. We have used this assay first to determine whether the floor plate, a cell group that has polarizing properties in neural tube and limb bud differentiation, is a local source of retinoids within the spinal cord. We have also examined whether the effects of exogenously administered retinoic acid on anteroposterior patterning of cells in the developing central nervous system correlate with differences in retinoid release from anterior and posterior neural tissue. We find that the release of morphogenetically active retinoids from the floor plate is only about 1.5-fold that of the dorsal spinal cord, which does not have neural tube or limb polarizing activity. These results suggest that the spatial distribution of retinoid release from spinal cord tissues differs from that of the neural and limb polarizing activity. This assay has also shown that retinoids are released from the embryonic spinal cord at much greater levels than from the forebrain. This result, together with previous observations that the development of forebrain structures is suppressed by low concentrations of retinoic acid, suggest that the normal development of forebrain structures is dependent on the maintenance of low concentrations of retinoids in anterior regions of the embryonic axis. This assay has also provided initial evidence that other embryonic tissues with polarizing properties in vivo release retinoids in vitro.

Effects of dietary aluminum excess and manganese deficiency on neurobehavioral endpoints in adult mice

Studies in mice have suggested that both dietary Al excess and dietary Mn deficiency promote oxidative tissue damage. To determine if these factors can interact to produce functional nervous system damage, female mice (N = 10-12 per group) were fed diets with control or low Mn (35 or 3 micrograms Mn/g diet) and/or control or high Al (25 or 1000 micrograms Al/g diet, Al as Al lactate) content for a 90-day period. No overt signs of neurotoxicity were observed in any group. Excess Al produced a threefold Al accumulation in both liver and brain, a slight acceleration of growth, decreased motor activity, decreased grip strength, and decreased startle responsiveness. Manganese deprivation led to liver, brain, and femur Mn depletion and reduced liver MnSOD activity but no neurobehavioral changes. No interactive effects between Al excess and Mn deficiency were observed. Neither Al excess nor Mn deficiency altered brain or liver lipid peroxidation measures. This study suggests that (1) subchronic dietary Al at doses of 1000 micrograms Al/g diet produces elevated brain Al and altered neurobehavioral indices in adult mice; (2) brain lipid peroxidation is not altered by this treatment; (3) dietary Mn deficiency does not influence Al neurotoxicity in adult mice.

[Alterations of Ulex europaeus agglutinin-1 receptor in human colorectal benign and malignant tumors]

The distributions and alterations of UEA-1 receptor in 116 human colorectal mucosa, included 20 normal mucosa, 16 inflammatory and 14 hyperplastic polyps, 34 adenomas, and 32 carcinomas, were studied with ABC technique. The results follow as: 1. There were positive staining of UEA-1 in proximal colon and negative in distal colon and rectum; 2. The frequency and intensity of UEA-1 receptor stained were increasing with the sequence of normal mucosa (7.7%), inflammatory polyps (25%), hyperplastic polyps (57.1%), adenomas (76.4%), and carcinomas (100%) in distal colon and rectum; 3. The staining pattern of UEA-1 in severe atypia adenomas was very similar to that in carcinomas and both of them were significantly difference from that in the other groups (P less than 0.05 or less than 0.01). The results suggested that UEA-1 receptor in distal colon and rectum may be considered as a probe studying course of malignant transformation and benefit to the diagnosis of carcinoma.

Radioimmunolocalization of human malignant tumors with In-111 labeled monoclonal antibody

An anti-human colon carcinoma monoclonal antibody 2C10 was radiolabeled with In-111 and studied in 15 patients with gastrointestinal and ovarian carcinoma. The labelling efficiency approached 100% and immunoactivity of the labeled antibody was over 75%. 2-3 mCi (1 mg) In-111-2C10 was given to the patients intravenously and scintigraphy was performed 72 hours after administration with a gamma camera. Specimens were also scanned in some of the patients. The resected tumors and remote margin were examined immunohistochemically. Positive scintigraphic images were obtained in 12/15 patients with colorectal cancer (10) and ovarian cancer (2). Negative results were seen in the two patients with gastric cancer. The scintigraphic results of 10 patients were confirmed surgically and pathologically. The remaining 5 were confirmed by endoscopy, B-ultrasonography or X-ray CT. Most patients had been definitely diagnosed before imaging except one patient with metastatic focus from ovarian cancer to colon and one with recurrent colon cancer were first detected with RIAD, showing the unique advantage the latfer. The high background radioactivity in the liver, however, is a conspicuous problem to be solved.

Influence of dietary-induced copper and manganese deficiency on ozone-induced changes in lung and liver antioxidant systems

The influence of an animal's copper (Cu) and manganese (Mn) status on its response to ozone was investigated in weanling mice. Control, Cu-deficient and Mn-deficient mice were exposed continuously to 1.2 ppm O3 or filtered air for 7 days. In control mice, ozone exposure resulted in higher lung activities of CuZnSOD, MnSOD and GPx. In contrast, Mn-deficient mice did not display increases in lung MnSOD, CuZnSOD or GPx activities following ozone exposure. Similarly, ozone-induced increases in lung CuZn-SOD and MnSOD activities were not observed in Cu-deficient mice, although lung GPx activity was increased in these mice relative to their air-breathing controls. These results show that an animal's Cu and Mn status can influence its response to ozone, and the data suggest that Cu- and Mn-deprived animals may be more susceptible to long-term or repetitive ozone exposure.

Cognitive impairment in musculoskeletal pain patients

To assess the incidence and relationship of cognitive/intellectual impairments to pain problems, seventy-three adults with musculoskeletal pain seen in a PM&R outpatient clinic were screened using the Neurobehavioral Cognitive Status Examination (NCSE). Subjective pain complaints were assessed using portions of the McGill Pain Questionnaire. Patients with prior diagnoses of neurocognitive problems or those who had taken narcotic analgesics in the last 24 hours were excluded. Results showed that 32 percent of subjects had impaired performance in at least one cognitive domain. Individuals with poorer performance on the NCSE had higher levels of reported pain or disability and psychological distress. Possible factors contributing to poor performance on cognitive tasks include psychological disorders or distress, undiagnosed organic brain dysfunction, social/psychological factors such as education, or a combination of these. Results suggest the need for further research to understand the relationship of poor performance on cognitive tasks to the etiology, maintenance and rehabilitation of pain problems.

Abdominoscrotal hydrocele--cause of abdominal mass in children

Abdominoscrotal hydrocele is relatively uncommon in adults and rare in children. The case presented typifies the classic features of the clinical presentation and the satisfactory response to conservative surgical therapy.