Reversal of established rat crescentic glomerulonephritis by blockade of macrophage migration inhibitory factor (MIF): potential role of MIF in regulating glucocorticoid production

Macrophage migration inhibitory factor (MIF) is a potent pro-inflammatory cytokine that also counter-regulates glucocorticoid action. We investigated whether immunoneutralization of MIF could reverse established experimental crescentic glomerulonephritis and if this treatment could modulate endogenous glucocorticoid levels. Accelerated anti-GBM glomerulonephritis was induced in six littermate pairs of rats. Once crescentic disease was established on day 7, one animal in each pair was given a daily injection of neutralizing anti-MIF antibody (Ab) or irrelevant isotype control Ab for 14 days and then killed on day 21. In addition, a group of 6 animals was killed on day 7 of disease without any treatment. Animals receiving the control Ab exhibited a rapidly progressive glomerulonephritis with severe renal injury (proteinuria), loss of renal function (creatinine clearance), anemia, and marked histologic damage (including glomerular crescent formation), compared with animals killed on day 7 without treatment. In contrast, anti-MIF Ab treatment partially reversed the disease by restoring normal renal function and reducing histological damage compared with untreated animals killed on day 7 (p < 0.05). Interestingly, anti-MIF Ab treatment also prevented severe anemia (p < 0.05). Reversal of disease was associated with a significant reduction in leukocyte infiltration and activation and renal interleukin-1 (IL-1) production. Importantly, anti-MIF Ab treatment caused a significant increase in endogenous serum corticosterone levels, which correlated with the reversal of disease parameters. In conclusion, this study has demonstrated that blocking MIF activity can partially reverse established crescentic glomerulonephritis and suggests that MIF operates by both enhancing the cellular immune response and suppressing the endogenous anti-inflammatory glucocorticoid response.

Cytoplasmic localization of LIM-kinase 1 is directed by a short sequence within the PDZ domain

LIM-containing protein kinase 1 (LIMK1) is a serine/threonine kinase with a structure composed of two LIM domains, a PDZ domain, and a protein kinase domain. We examined the subcellular localization of LIMK1 and its variously deleted mutants in HeLa cells by transfection with these cDNAs. Immunofluorescence analysis revealed that the full-length LIMK1 and its mutants deleted with LIM domain or protein kinase domain preferentially localized in the cytoplasm, while the mutants deleted with the PDZ domain or a 52 amino acid region (B region) within the PDZ domain localized mainly in the nucleus. When the normally nuclear cyclin A was fused with the PDZ domain or the B region of LIMK1, it was localized in the cytoplasm of transfected cells. The corresponding region of the PDZ domain of postsynaptic density protein (PSD)-95 had no such function. Additionally, the PDZ domain of LIMK1 had no potential to bind to the C-terminal S/TXV peptides, to which the PSD-95 PDZ domain can bind. Taken together these results suggest that the PDZ domain, particularly the B region, of LIMK1 has a specific function to localize the protein in the cytoplasm. When glutathione S-transferase (GST) fused with the PDZ domain of LIMK1 (GST-PDZ) or GST-PDZ deleted with the B region (GST-PDZ delta B) was microinjected into the nucleus of COS cells, GST-PDZ was almost completely excluded from the nucleus within 30 min, whereas GST-PDZ delta B remained in the nucleus. These findings suggest that the B region of LIMK1 probably has nuclear export signal activity.

[Research and development of the surface EMG detection and analysis system]

To meet the requirement of developing myoelectric controller for a man-machine systems, a surface electromyography (EMG) detection and analysis system is discussed in this paper. This system consists of two parts--data acquisition hardware and signal processing software. In the surface EMG acquisition system both wire and wireless TELEMG are available. In the surface EMG processing system various methods are integrated such as the methods in time domain, the methods for frequency analysis, and also including some newly developed methods, e.g., wavelet transform and fractal analysis. This system provides a useful platform for research and development of the myoelectric controller that is widely used in rehabilitation engineering products.

[Alanyl-glutamine dipeptides protected the liver function by increasing the hepatic glutathione]

OBJECTIVE

Glutathione (GSH) is a major antioxidant which protects hepatic tissues from free radical injury. Alanyl-Glutamine (ALA-GLN) proved to be a precursor of GSH synthesis, was used to investigate the relationship to GSH biosynthesis which may be effective for hepatic protection.

METHODS

20 male Wistar rats were randomly divided into two groups receiving standard parenteral nutrition (STD) supplemented with or without ALA-GLN for 7 days. At 5th day 5-fluorouracil (5-FU) was injected peritoneally, the blood samples for GSH, GSSG, ALT (sGPT), AKP and TBilli tests were measured after 4-8 h.

RESULTS

The concentration measurements were significantly different in ALA-GLN group compared with STD animals in serum GLN (687.3 +/- 49.8) vs (504.9 +/- 38.6) mumol/L, P < 0.05), serum GSH (14.37 +/- 5.16) vs (7.08 +/- 3.16) mumol/L, P < 0.01) and in liver GSH content (6.86 +/- 2.46) vs (4.38 +/- 1.63) mumol/g liver tissue, P < 0.05). Rats in ALA-GLN group have lesser elevations in hepatic enzymes after 5-FU administration.

CONCLUSIONS

The supplemented nutrition ALA-GLN protected the liver function through increasing the glutathione biosynthesis and preserving the glutathione stores of hepatic tissue.

A comparative study of transvaginal ultrasonography and pelvic arteriogram in assessment of patients with gestational trophoblastic tumour

OBJECTIVE

To compare the reliability of transvaginal ultrasonography with pelvic arteriography in the assessment of patients with gestational trophoblastic disease.

METHODS

Transvaginal ultrasonography was performed in 24 patients with gestational trophoblastic tumour. Within one week after ultrasound investigation, pelvic arteriography was carried out in each patient. Of 24 cases, 16 patients hadn't been treated by chemical reagent, 5 had accepted 2 to 5 courses of chemotherapy, and 3 had achieved complete remission before both investigations performed.

RESULTS

In 3 patients with complete remission, 2 had no evidence of abnormal findings either on transvaginal ultrasonography or on pelvic arteriography, 1 showed intramyometrial lesions by both methods. In the remaining 21 patients, all demonstrated a abnormal uterine image, and 5 of them accompanied with the finding of parametrium metastatic signs by transvaginal ultrasonography; these abnormal results were confirmed by pelvic arteriographic imaging. However, in two cases without clinical and ultrasonic signs of parametrium metastasis, pelvic arteriography indicated the early metastasis of parametrium vessels.

CONCLUSIONS

Even though it is difficult to predict the early parametrium metastasis in patients with gestational trophoblastic disease by B-ultrasonic investigation, our data would support the introduction of transvaginal ultrasonography in the diagnosis and evaluation of gestational trophoblastic tumour.

De novo glomerular osteopontin expression in rat crescentic glomerulonephritis

Osteopontin (OPN) is a secreted acidic glycoprotein that has potent monocyte chemoattractant and adhesive properties. Up-regulation of tubular OPN expression is thought to promote interstitial macrophage infiltration in experimental nephritis; however, the role of OPN in glomerular lesions, particularly crescent formation, is unknown. The present study used Northern blotting, in situ hybridization and immunohistochemistry to examine OPN expression in a rat model of accelerated anti-GBM glomerulonephritis. Osteopontin mRNA and protein is expressed by some parietal epithelial cells, thick ascending limbs of Henle and medullary tubules and collecting ducts in normal rat kidney. De novo OPN mRNA and protein expression was evident in glomerular visceral and parietal epithelial cells in anti-GBM glomerulonephritis. Glomerular OPN expression preceded and correlated with macrophage infiltration in the development of hypercellularity, focal and segmental lesions and, notably, crescent formation. There was marked up-regulation of OPN expression by tubular epithelial cells that also preceded and correlated with interstitial macrophage (r = 0.93, P < 0.001) and T-cell infiltration (r = 0.85, P < 0.001). Both glomerular and tubular OPN expression correlated significantly with proteinuria (P < 0.001) and a reduction in creatinine clearance (P < 0.01). In addition, double immunohistochemistry showed co-expression of osteopontin and one of its ligands, CD44, in intrinsic renal cells. CD44 and OPN expression by parietal epithelial cells was evident in crescent formation, while virtually all OPN-positive tubules expressed CD44. Infiltrating macrophages and T-cells were CD44-positive, but only a small proportion of T-cells and few macrophages showed OPN expression. Interestingly, strong OPN mRNA and protein expression was seen in macrophage multinucleated giant cells. In summary, this study suggests that OPN promotes macrophage and T-cell infiltration in the development of renal lesions in rat anti-GBM glomerulonephritis, including glomerular crescent and multinucleated giant cell formation.

The mouse estrogen receptor-related orphan receptor alpha 1: molecular cloning and estrogen responsiveness

Estrogen receptor-related orphan receptor alpha 1 is a member of the steroid/thyroid nuclear receptor superfamily. We have previously cloned the human estrogen receptor-related orphan receptor alpha 1 (hERR alpha 1) cDNA and demonstrated that it enhances estrogen responsiveness of the lactoferrin gene promoter in transfected human endometrial carcinoma cells. In the present study, we used the hERR alpha 1 cDNA as a probe and isolated the mouse homologue of ERR alpha 1 from the cDNA libraries of the brain and kidney. Sequence comparison between human and mouse ERR alpha 1 (mERR alpha 1) revealed that the homologies are 89% in nucleotides and 97% in amino acids. By electrophoresis mobility shift assay, we showed that the glutathione S-transferase-mERR alpha 1 fusion protein produced in a bacterial system bound to the human ERR alpha 1 DNA-binding element. Mouse uterine nuclear extract also interacted with this DNA element and produced three complexes in the mobility shift assay, one of which was supershifted by the hERR alpha 1 antiserum. A 2.2 kbp transcript was detected by Northern analysis in all adult mouse tissues tested; however, large variations in the amount of ERR alpha 1 mRNA were found among them. Multiple immunoreactive forms of mouse ERR alpha 1 were detected by Western analysis in non-reproductive tissues, whereas a major 53 kDa protein was found in reproductive tissues such as uterus, cervix and vagina. Diethylstilbestrol (DES) stimulated the expression of ERR alpha 1 mRNA in the uterus of 19-day-old mouse. We showed that DES and estradiol, but not progesterone or dexamethasone, enhanced the level of immunoreactive ERR alpha 1 in the mouse uterus. These results demonstrated that the ERR alpha 1 is an estrogen-responsive gene in the mouse uterus and provides a model system with which to study the biological roles of this nuclear orphan receptor.

[Simultaneous determination of matrine and oxymatrine in jieeryin and fuyanshuan by RP-HPLC]

Matrine and oxymatrine in Jieeryin and Fuyanshuan were separated and determined by Reversed Phase High Performance Liquid Chromatography, A chromatographic method for the separation and determination of matrine and oxymatrine in these preparations was established. Chromatographic coditions: ODS column with methanol-water-triethylamine(55:45:0.02) as the mobil phase, and UV detection at 215 nm. The method is simple, sensitive and accurate. This study provides the scientific basis for quality evaluation and quality control in making these preparations.

Macrophage and myofibroblast proliferation in remnant kidney: role of angiotensin II

Local macrophage proliferation has been shown to be a major mechanism of macrophage accumulation in several immunologically-induced animal models of renal diseases. This study has explored whether local proliferation of macrophages and myofibroblasts contribute to their accumulation in rat remnant kidney model and investigated the role of angiotensin II (Ang II) in these cellular pathological events by blocking the angiotensin II activity with ramipril, and angiotensin converting enzyme (ACE) inhibitor, or valsartan, an Ang II type 1 receptor antagonist. There was local proliferation of macrophages and myofibroblasts within renal parenchyma following renal ablation, contributing significantly to macrophage and myofibroblasts accumulation, renal dysfunction and fibrosis. Both treatment resulted in inhibition of local proliferation of macrophages and myofibroblasts and this was associated with attenuation of renal injury. In conclusion, inhibition of local macrophage and myofibroblast proliferation may be an important mechanism by which Ang II blockade attenuated renal injury following renal ablation.

[Studies on hydrolysis of anti-HRV IgY and its oral passive immunity effect to human rotavirus]

In this paper, hens of fine breed were immunized with human rotavirus (HRV), and the anti-HRV IgY was isolated and purified from their eggs collected daily. In addition, the resistance of anti-HRV IgY to hydrolysis of gastric juice and proteases in human digestive tract, the safety of IgY and the effectiveness of IgY in clinical use were observed as well. The results showed that anti-HRV IgY has a fairly good resistance to gastroinstestinal proteases. The safety of using anti-HRV IgY was affirmed by oral administration to mice of a solution of IgY. In clinical test the IgY has been proved to be anti-HRV and, therefore, effective against infections of infant diarrhea induced by HRV.

Probing the outer vestibule of a sodium channel voltage sensor

The second and third basic residues of the S4 segment of domain 4 (D4:R2 and D4:R3) of the human skeletal muscle Na+ channel are known to be translocated from a cytoplasmic to an extracellular position during depolarization. Accessibilities of individual S4 residues were assayed by alteration of inactivation kinetics during modification of cysteine mutants by hydrophilic methanethiosulfonate reagents. The voltage dependences of the reaction rates are identical for extracellular application of cationic methanethiosulfonate-ethyltrimethylammonium (MTSET) and anionic methanethiosulfonate-ethylsulfonate (MTSES), suggesting that D4:R3C is situated outside the membrane electric field at depolarized voltages. The absolute rate of R3C modification is 281-fold greater for MTSET than for MTSES, however, suggesting that at depolarized voltages this S4 thiol resides in a negatively charged hydrophilic crevice. The two hydrophobic residues between D4:R2C and D4:R3C in the primary sequence (L1452 and A1453) are not externally exposed at any voltage. An alpha-helical representation of D4/S4 shows that the basic residues D4:R2 and D4:R3 are on the face opposite that of L1452 and A1453. We propose that in the depolarized conformation, the hydrophobic face of this portion of D4/S4 remains in contact with a hydrophobic region of the extracellular vestibule of the S4 channel.

[The decrease of gastric mucosal blood flow in obstructive jaundice under stress]

OBJECTIVE

To investigate the cause of decrease of gastric mucosal blood flow (GMBF) in obstructive jaundice under stress.

METHODS

With common bile duct ligation (CBDL) in Wistar rats under cold restraint stress, GMBF and the content of Endothelin-1, Angiotensin-II, H2, alpha 1 receptor in gastric mucosa were measured. Before stress anti-ET-1 serum, Enalapril, Cimentidine and Phetolamins were administrated, and the change of GMBF was studied.

RESULTS

GMBF was significantly decreased in CBDL in stress than those in control subjects. The content of ET1 and Ang-II was significantly increaced, the density of H2 and alpha 1 receptor was significantly decreased. Before stress antagonist was administrated, and GMBF was significantly increased.

CONCLUSION

GMBF was decreased by increased ET, Ang-II and decreased H2, alpha 1 receptor in CBDL, under stress. Antagonist improved gastric mucosal blood flow. They had protection from gastric mucosa.

Characterization of the alpha1B-adrenergic receptor gene promoter region and hypoxia regulatory elements in vascular smooth muscle

We previously demonstrated that alpha1B-adrenergic receptor (AR) gene transcription, mRNA, and functionally coupled receptors increase during 3% O2 exposure in aorta, but not in vena cava smooth muscle cells (SMC). We report here that alpha1BAR mRNA also increases during hypoxia in liver and lung, but not heart and kidney. A single 2.7-kb alpha1BAR mRNA was detected in aorta and vena cava during normoxia and hypoxia. The alpha1BAR 5' flanking region was sequenced to -2,460 (relative to ATG +1). Transient transfection experiments identify the minimal promoter region between -270 and -143 and sequence between -270 and -248 that are required for transcription of the alpha1BAR gene in aorta and vena cava SMC during normoxia and hypoxia. An ATTAAA motif within this sequence specifically binds aorta, vena cava, and DDT1MF-2 nuclear proteins, and transcription primarily initiates downstream of this motif at approximately -160 in aorta SMC. Sequence between -837 and -273 conferred strong hypoxic induction of transcription in aorta, but not in vena cava SMC, whereas the cis-element for the transcription factor, hypoxia-inducible factor 1, conferred hypoxia-induced transcription in both aorta and vena cava SMC. These data identify sequence required for transcription of the alpha1BAR gene in vascular SMC and suggest the atypical TATA-box, ATTAAA, may mediate this transcription. Hypoxia-sensitive regions of the alpha1BAR gene also were identified that may confer the differential hypoxic increase in alpha1BAR gene transcription in aorta, but not in vena cava SMC.

Human estrogen receptor-like 1 (ESRL1) gene: genomic organization, chromosomal localization, and promoter characterization

Estrogen receptor-like 1a (ESRL1a; same as estrogen receptor-related orphan receptors, ERR1) belongs to a subfamily of the nuclear receptor superfamily. We have previously shown that human ESRL1a modulates estrogen responsiveness of the lactoferrin gene promoter in transiently transfected endometrial carcinoma RL95-2 cells. In this study, we cloned and characterized the human ESRL1 gene. Through the fluorescence in situ hybridization method, the ESRL1 gene was localized to the centromere region of chromosome 11q12. Partial sequencing, restriction mapping, and PCR analysis revealed that the ESRL1 gene consists of seven exons and is approximately 20 kb in length. We found that the smallest exon (exon 3) contains 117 bp and the largest exon (exon 7) has 1032 bp. The smallest intron (intron 5) is only 88 bp long and the largest intron (intron 2) is 8 kb long. All introns have the conserved GT and AG dinucleotides present at the donor and acceptor sites, respectively. Like the estrogen receptor, the highly conserved DNA-binding domain of hESRL1a is encoded by exon 2 and exon 3, and the intron/exon junctions (2 and 3) are well conserved between the two genes. Primer extension analysis revealed multiple transcription initiation start sites in human uterine (HeLa, HEC, and RL95-2) cell lines. However, one major initiation start site was found by RNase protection assay. The hESRL1a mRNA is differentially expressed in various human tissues. The nucleotide sequence adjacent to the transcription start sites of the ESRL1 lacks the typical TATA and CAAT boxes but is GC rich and contains 10 consensus Sp1-binding elements and two E boxes. The region that contains these transcription factor-binding elements showed a high level of promoter activity when transiently transfected into RL95-2 cells.

[Experimental study on effect of zhuyu tongfu mixture on anti-enterogenous infection caused by endotoxin]

OBJECTIVE

To evaluate the effect of Zhuyu Tongfu mixture (ZYTFM) in curing enterogenus infection.

METHODS

Experimental model of enterogenous infection in mice caused by endotoxin was used. The positive translocation trate (PTR) and mumber of viable bacteria in viscera and serum level of superoxide dismutase (SOD) were measured before and after ZYTFM treatment.

RESULTS

The PTR and number of viable bacteria in liver, spleen and mesocolon in the ZYTFM group were much lower than those in the model group and the placebo group (P < 0.01). Whereas the SOD level of the ZYTFM group was significantly higher than that in the latter two groups (P < 0.05-0.01). Pathological examination displayed that ZYTFM could markedly alleviate the mucosal damage of small intestine.

CONCLUSION

ZYTFM has an obvious curative effect on enterogenous infections induced by endotoxin.

Macrophage apoptosis in rat crescentic glomerulonephritis

The fate of macrophages at the site of inflammation is unknown. We investigated this question in a macrophage-mediated model of crescentic glomerulonephritis in which macrophage accumulation is relatively stable despite the presence of high levels of local macrophage proliferation. Accelerated anti-glomerular basement membrane glomerulonephritis was induced in groups of six rats that were killed on day 1, 7, 14, or 21. Macrophage apoptosis was demonstrated in kidney sections by three methods: in situ terminal deoxyribonucleotide transferase (TdT)-mediated dUTP nick end labeling (TUNEL) combined with ED1 antibody immunostaining of macrophages, ED1 immunostaining combined with classical nuclear morphology, and electron microscopy. Substantial macrophage apoptosis became evident on day 14 of the disease, following the appearance of high levels of macrophage proliferation. The parallel relationship between proliferation and apoptosis is the likely explanation for the stabilization of macrophage numbers within the inflamed kidney. A striking feature was that macrophage proliferation and apoptosis was largely restricted to areas of focal damage, such as in the development of glomerular crescents. Increasing levels of macrophage proliferation and apoptosis were evident as crescents developed from a cellular to a fibrocellular phenotype, with a dramatic reduction in both of these processes in the progression to a fibrotic phenotype, suggesting an important role for macrophage apoptosis in the resolution of fibrocellular crescents to an acellular fibrotic structure. In conclusion, this study has identified apoptosis as an important mechanism counterbalancing local proliferation in the regulation of macrophage accumulation at sites of inflammation. Indeed, apoptosis may be a central regulator of the progression and resolution of macrophage-mediated tissue injury.

CRE-like response element regulates expression of rat alpha 2D-adrenergic receptor gene in vascular smooth muscle

Contractile and binding studies indicate that alpha 2-adrenergic receptors (ARs) are differentially expressed by vascular smooth muscle cells (SMCs) according to vascular segment (artery, arteriole, vein). In the present study, alpha 2D-AR mRNA was two- to threefold higher in vena cava than in aorta. To understand vascular regulation of alpha 2D-AR expression in these cells, we sequenced 2.8 kb of the 5' flanking region of the alpha 2D-AR gene. Notable features include two potential TATA boxes, an adenosine 3',5'-cyclic monophosphate response element (CRE)-like binding element, and an Sp1 element. Comparison of the rat and human genes revealed an overall homology of 74% over the 1.87-kb sequence 5' to the translation initiator methionine, including complete homology at the distal TATA, CRE-like, and Sp1 sites, alpha 2D-AR transcription starts from the guanine nucleotide 18 base pair downstream from the distal TATA box. Reporter gene constructs demonstrated strong alpha 2D-AR promoter activity, but with several differences in construct activity, in both rat aorta and vena cava SMCs. Analysis of an essential promoter fragment revealed two regions protected by aorta and vena cava SMC nuclear proteins. The core sequences of these protected regions are TGACGCTA and TATAA. The former CRE-like element conferred specific binding of both aorta and vena cava nuclear proteins. In addition, promoter activity was increased 300% by forskolin or 8-bromoadenosine 3',5'-cyclic monophosphate, indicating that the CRE-like element may regulate alpha 2D-AR expression in vascular tissue.

Intrinsic renal cells are the major source of interleukin-1 beta synthesis in normal and diseased rat kidney

BACKGROUND

A number of studies have demonstrated a pathological role for interleukin-1 (IL-1) in experimental models of glomerulonephritis, but the cellular pattern of renal IL-1 production remains poorly characterized. The aim of this study, therefore, was to identify the cell types expressing IL-1 in normal and diseased rat kidney.

METHODS

Renal IL-1 beta expression was examined in normal rats and during a 21-day time course of rat accelerated anti-GBM glomerulonephritis by northern blotting, in situ hybridization and double immunohistochemistry.

RESULTS

Interleukin-1 beta mRNA expression was readily detectable in normal rat kidney by northern blot analysis and in situ hybridization. Immunohistochemistry staining demonstrated constitutive IL-1 beta expression by glomerular endothelial cells and cortical tubular epithelial cells. There was a marked increase in whole kidney IL-1 beta mRNA in rat anti-GBM glomerulonephritis. Glomerular IL-1 beta immunostaining was upregulated, being expressed by podocytes, mesangial cells and infiltrating macrophages, and was particularly prominent within glomerular crescents. Double staining with the ED1 antibody showed IL-1 beta expression in up to 13% of glomerular macrophages, whereas 48% of macrophages within crescents stained for IL-1 beta. However, the most marked increase in IL-1 beta expression was seen in cortical tubular epithelial cells, particularly in areas of tubular damage. In situ hybridization confirmed that tubular IL-1 beta staining was due to local cytokine synthesis rather than protein absorption.

CONCLUSIONS

This study has identified constitutive IL-1 beta expression by glomerular endothelium and tubular epithelial cells in normal rat kidney. In addition, the marked upregulation of IL-1 beta expression by intrinsic glomerular cells and tubules in rat anti-GBM disease suggests an important role for these cells in IL-1 dependent crescent formation and tubulointerstitial injury.

[Effect of recombinant growth hormone on amino acids metabolism in blood and urine after major operation]

To determine the effects of recombinant human growth hormone (GH) on postoperative amino acids metabolism, we performed a placebo-controlled randomized double-blind trial in 18 patients after elective gastrectomy or colectomy. The same amount of calories and amino acids were administered. Research group was daily injected growth hormone 0.15 IU/(kg.day) and control group was given placebo during the first postoperative week. All urine were analyzed for nitrogen balance and excretion of 3-methylhistidine. On the seventh postoperative day while the parenteral nutrients were being infused, amino acid exchange across the forearm was measured. On the seventh postoperative day all patients' amino acids in plasma were slightly increased by comparing with preoperative day but was not statistical significance. Forearm arterial-venous difference (A-V) measured on POD + 7 was markedly different between groups. There was continued release of amino acids from the forearm in the control subjects, while there was marked amino acid uptake in the GH patients (total amino acid nitrogen exchange was -398 +/- 158 mumol/L vs +165 +/- 61 mumol/L, P < 0.01). Excretion of urinary 3-methylhistidine in control group loss more than in GH group (7.3 +/- 1.0 mumol/(kg.24 h) vs 4.4 +/- 0.3 mumol/(kg.24 h), P < 0.05). The results demonstrated that GH can increase the uptake of amino acid from forearm and decrease the excreation of 3-methylhistidine in urine after operation, but did not disturb the balance of amino acids in plasma.

Alpha1D-adrenergic receptors and mitogen-activated protein kinase mediate increased protein synthesis by arterial smooth muscle

Catecholamines may influence vascular smooth muscle cell (SMC) growth and vascular hypertrophic diseases. We previously demonstrated that stimulation of alpha1-adrenoceptors (AR) causes hypertrophy of vascular SMCs in vitro and in situ. Here, we used adult rat aorta SMCs that express alpha1D- and alpha1B-ARs (but not alpha1A-ARs) in vitro to examine the mechanisms and alpha1-AR subtypes involved. Norepinephrine (NE) increased protein synthesis and content in a time- and dose-dependent manner. To identify the responsible alpha1-AR subtype, we first documented the selectivity of two alpha1-AR subtype antagonists, BMY 7378 (alpha1D-AR antagonist) and chloroethylclonidine (CEC; alpha1B-AR antagonist), using Rat-1 fibroblasts stably transfected with the three different rodent alpha1-AR cDNAs. NE dose-dependently increased protein synthesis in each cell line. In alpha1D fibroblasts, BMY 7378 inhibited growth and protected alpha1D-ARs from CEC alkylation while having little blocking or protecting effect on the growth induced by stimulation of fibroblasts that express alpha1A- or alpha1B-ARs. In rat aorta SMCs, pretreatment with CEC in the presence of BMY 7378 to protect alpha1D-ARs had no effect on NE-induced protein synthesis. BMY 7378 inhibited the SMC growth response with a pKb of 8.4. NE caused rapid and transient p42-p44 mitogen-activated protein kinase (MAPK) activation that was alpha1D-AR dependent. Furthermore, NE caused tyrosine phosphorylation of multiple cellular proteins, phosphorylation of Raf-1, and stimulation of c-fos mRNA expression in aorta SMCs. The selective MAPK kinase inhibitor PD 98059 inhibited NE-induced protein synthesis and MAPK activation with IC50 values of 2.3 and 1.6 microM, respectively. These data demonstrate that SMC growth induced by NE is mediated by alpha1D-ARs that couple to activation of the MAPK cascade.

The pathogenic role of macrophage migration inhibitory factor in immunologically induced kidney disease in the rat

Macrophage migration inhibitory factor (MIF) plays a pivotal role in the inflammatory response in endotoxemia and in the delayed-type hypersensitivity response, but its potential as a regulator of immunologically induced disease is unknown. We have addressed this issue by administering a neutralizing anti-MIF antibody in a rat model of immunologically induced crescentic anti-glomerular basement membrane (GBM) glomerulonephritis. Six individual experiments using paired inbred littermates were performed. Rats were primed with rabbit immunoglobulin on day -5 and then injection with rabbit anti-rat GBM serum on day 0. Pairs of animals were treated with anti-MIF or a control monoclonal antibody from the time of anti-GBM serum administration until being killed 14 d later. Control antibody-treated animals developed severe proteinuria and renal function impairment with severe histological damage due to marked leukocytic infiltration and activation within the kidney. In contrast, anti-MIF treatment substantially reduced proteinuria, prevented the loss of renal function, significantly reduced histological damage including glomerular crescent formation, and substantially inhibited renal leukocytic infiltration and activation (all P <0.001 compared with control treatment). Inhibition of renal disease by anti-MIF treatment was attributed to preventing the marked upregulation of interleukin-1beta, leukocyte adhesion molecules including intercellular adhesion molecule-1 and vascular cell adhesion molecule-1, and inducible nitric oxide synthase expression seen in the control antibody-treated animals. This inhibition of progressive renal injury was mirrored by the complete suppression of the skin delayed-type hypersensitivity response to the challenge antigen (rabbit IgG). Interestingly, anti-MIF treatment did not effect the secondary antibody response or immune deposition within the kidney, indicating that MIF participates in cellular-based immunity in this primed macrophage-dependent anti-GBM glomerulonephritis. In conclusion, this study has demonstrated a key regulatory role for MIF in the pathogenesis of immunologically induced kidney disease. These results argue that blocking MIF activity may be of benefit in the treatment of human rapidly progressive glomerulonephritis, and suggest that MIF may be important in immune-mediated disease generally.

Inhibition of activated Ras-induced neuronal differentiation of PC12 cells by the LIM domain of LIM-kinase 1

LIM-kinase 1 and 2 (LIMK1 and LIMK2) are members of a novel class of protein kinases with structures composed of two LIM motifs at the N-terminus and an unusual protein kinase domain at the C-terminus. The cellular functions of the LIMK family proteins have remained unknown. In the present study, we examined effects of LIMKs on neuronal differentiation of PC12 pheochromocytoma cells. Transient expression analyses revealed that LIMK1, in itself, had no apparent effect on PC12 cells, but the oncogenic Ras-induced differentiation of PC12 cells was notably inhibited by co-expression with LIMK1 or LIMK2. A mutant of LIMK1 lacking a protein kinase domain (delta K) similarly inhibited Ras-induced differentiation of PC12 cells, but a mutant lacking a LIM domain (delta LIM) failed to do so, indicating that a LIM domain but not a protein kinase domain is required for the inhibitory activity. This notion was further supported by the finding that mutation, changing conserved cysteines involved in zinc coordination to glycines in both of two LIM motifs, abolished the inhibitory activity of delta K. Additionally, we also found that the constitutively activated MAP kinase kinase (MAPKK)-induced differentiation of PC12 cells was inhibited by co-expression with delta K. Furthermore, AK did not inhibit the kinase activity of MAP kinase (MAPK) stimulated by MAPKK, when co-expressed in COS7 cells. These findings suggest that LIMK1 inhibits neuronal differentiation of PC12 cells, through its LIM domain and by interfering with events downstream of MAPK activation.

Two-dimensional film dosimetry application in heterogeneous materials exposed to megavoltage photon beams

Measurement of dose within tissues and tissue interfaces having sharp density discontinuities and heterogeneities (such as in the lung, esophagus, and rectum) is essential for treatment plan verification and accurate prediction of the prescribed dose. This study examines the feasibility and utility of simplifying standard film dosimetry to measure dose distributions deposited by megavoltage beams in tissue substitutes (such as cork for lung) and anthropomorphic phantoms which closely resemble human tissues having large density heterogeneities and having sharp tissue interfaces. In addition, film dosimetry determined the dose distribution involving superposition of multiple radiation fields and helped evaluate the accuracy of a commercial treatment planning program which incorporates tissue heterogeneity effects through the "effective path length" algorithm. This study shows that these treatment planning programs and simple calculations overestimate the dose delivered within the lower density material in heterogeneous regions.

TNF-alpha up-regulates renal MIF expression in rat crescentic glomerulonephritis

BACKGROUND

Macrophage migration inhibitory factor (MIF) is a potent proinflammatory mediator that participates in the pathogenesis of endotoxemia and experimental crescentic glomerulonephritis. However, very little is known about how MIF production is regulated in disease. We therefore examined whether tumor necrosis factor alpha (TNF-alpha), a known inducer of MIF expression by macrophages in vitro, up-regulates local and systemic MIF expression in a macrophage-mediated rat model of crescentic glomerulonephritis.

MATERIALS AND METHODS

Anti-glomerular basement membrane (GBM) glomerulonephritis was induced in groups of six primed rats. Animals were treated with 1 mg/kg soluble TNF-alpha receptor (TNFbp) or saline from the time of disease induction until they were killed on Days 1, 7, or 14. Renal MIF expression was assessed by in situ hybridization, immunohistochemistry, and ELISA, and compared with macrophage accumulation and indices of renal damage.

RESULTS

Although TNFbp treatment on Day 1 of the disease had only a partial effect upon the up-regulation of glomerular MIF expression, on Days 7 to 14 it almost completely abrogated the increase in glomerular and interstitial MIF mRNA and protein expression. In addition, TNFbp treatment significantly inhibited MIF secretion by cultured glomeruli and reduced serum MIF levels. The inhibition of renal MIF expression was paralleled by a significant inhibition of glomerular and interstitial macrophage infiltration (p < 0.001 versus saline treated), a significant suppression of renal injury (proteinuria and serum creatinine), and a marked reduction in histologic damage (glomerular hypercellularity, crescent formation, and interstitial fibrosis; all p < 0.01 versus saline treated).

CONCLUSIONS

This study demonstrates for the first time that TNF-alpha up-regulates local MIF expression by both infiltrating macrophages and resident kidney cells in rat crescentic glomerulonephritis. In addition, TNF-alpha regulates systemic MIF production. Thus, TNF-alpha, together with MIF, may play a pathological role in immunologically induced renal disease.

Self-association of LIM-kinase 1 mediated by the interaction between an N-terminal LIM domain and a C-terminal kinase domain

LIM-kinase 1 (LIMK1) and 2 (LIMK2) are members of a novel class of protein kinases containing two LIM motifs at the N-terminus. The LIM motif is thought to be involved in protein-protein interactions. We report here evidence that LIMK1 self-associates and also associates with LIMK2. In vivo and in vitro binding analyses using variously deleted mutants of LIMKI revealed that the self-association of LIMK1 was caused by interaction between the N-terminal LIM domain and the C-terminal kinase domain. The association of LIMK1 with itself and with LIMK2 is important for understanding how activities and functions of LIMK family kinases are regulated.

[Percutaneous transluminal angioplasty for the treatment of occlusion of proximal subclavian artery]

Percutaneous transluminal angioplasty (PTA) is a well-established treatment for patients with stenosis of limb arteries. However, its efficacy for treatment of severe stenosis and occlusions of the subclavian artery is unclear. We attempted to recanalize the subclavian artery in 30 patients with severe stenosis or total occlusion of proximal subclavian artery and successful outcomes were seen in 27 cases (90%). In two patients the regional arterial thrombolysis with the PTA prcedure we used was found successful. There was no severe complications. During an average 6-month follow-up stenosis recurred in 2 patients, but the subclavian artery was recanalized by repedted PTA.

De Novo renal expression of macrophage migration inhibitory factor during the development of rat crescentic glomerulonephritis

Macrophage migration inhibitory factor (MIF), a key mediator of the delayed-type hypersensitivity response, was originally thought to be produced by activated T cells. However, recent studies have found that MIF is produced in many cell types including monocytes/macrophages and anterior pituitary cells. The current study has examined MIF expression in normal and diseased kidney using in situ hybridization, immunohistochemistry, and Northern blotting. MIF mRNA and protein are constitutively expressed in normal kidney, being largely restricted to tubular epithelial cells and some glomerular visceral and parietal epithelial cells. During the development of rat anti-glomerular basement membrane glomerulonephritis, a model of macrophage-mediated renal injury, there was marked de novo expression of MIF by intrinsic kidney cells including endothelium and glomerular and tubular epithelial cells. Up-regulation of MIF expression correlated with macrophage accumulation within the glomerulus (P < 0.001) and tubulointerstitium (P < 0.001). Of significance, the accumulation of macrophages was exclusively localized to areas of strong MIF expression, contributing to focal glomerular and tubulointerstitial lesion formation. In addition, up-regulation of MIF expression by parietal epithelial cells was associated with macrophage accumulation within Bowman's space and crescent formation. Combined in situ hybridization and immunostaining also demonstrated MIF expression by macrophages, T cells, and fibroblast-like cells within renal lesions. In conclusion, these data provide the first demonstration that renal epithelial cells are a major source of MIF in both normal and diseased kidney. Furthermore, the up-regulation of MIF expression may play an important role in macrophage accumulation and progressive renal injury in rat crescentic glomerulonephritis.

[Management of coagulation dysfunction in critically surgical patient]

12 surgical critically ill patients were studied for a better management of perioperative coagulation dysfunction. Their primary disease, clinical manifestation as well as some coagulation tests before and after therapy were retrospectively analysed. The result showed that secondary disseminated intravascular coagulation (DIC) is the main type of perioperative coagulation disorder, especially in decompensated hepatopathy and severe sepsis patients. It should be emphasized that: control of primary disease, effective drainage of focus, strict indication for 2nd surgical hemostasis and correct operation are required. For those hepatopathy with hypofibrinogenemia, some hemostatic drugs should be prohibited or very carefully used, in order to avoid the activation of plasmin and the exhaustion of fibrin. The early administration of heparin and aprotinin after the supplement of fibrinogen has shown a great potential benifit to stop the cascade of hypercoagulation and hyperplasminogenemia by enhancing the level of AT-III and fibrinogen in plasma.

[Construction of gene library of attenuated liver hepatitis A vaccine (H2 strain)]

OBJECTIVE

To determine the complete gene library of attenuated live hepatitis A vaccine (H2 strain) from cloned cDNA by application of reverse transcription (RT) and polymerase chain reaction (PCR) technique.

METHODS

Attenuated HAV H2 strain that was selected and studied in China was proven attenuated for human beings and proved to be effective in preventing hepatitis A.

RESULTS

Ten overlapping cDNA clones were obtained in addition to spanned the entire genome. The restriction enzyme mapping was also determined.

CONCLUSION

The gene library will benefit for the sequence of HAV cDNA and study on attenuation.

[Selective arterial catheterization in the management of drug-resistant choriocarcinoma]

OBJECTIVE

In order to save the life of the patients with drug-resistant choriocarcinoma due to improper treatment, selective arterial catheterization was used.

METHODS

All the 71 cases were treated with systemic chemotherapy together with pelvic selective arterial chemotherapy. 5 of them had arterial chemotherapy plus arterial embolization for hemorrhage. In 13 patients who had lung metastasis, intraarterial injection of methotrexate (MTX) through bronchial arterial was added.

RESULTS

55 of 71 (77.8%) achieved complete remission and 10 (14.1%) had partial remission. One patient failed to follow-up. 5 died of various causes during hospitalization. On Follow-up 12 had survived for more than 5 years with no signs of recurrence. 2 of them had childbirth after recovery.

CONCLUSION

Systemic intravenous infusion chemotherapy in combination with arterial chemotherapy is useful for drug-resistant choriocarcinoma. In patients with intraperitoneal hemorrhage caused by tumor rupture, selective arterial embolization should be used as emergency treatment to effectively control the bleeding, in order that patients will have a chance for further chemotherapy.

Spectral editing in 13C CP/MAS experiments at high magnetic field

We show that the spinning side-bands of protonated and non-protonated carbon atoms can be well separated by means of the standard SCP and LCPD experiments at a relatively slow sample spinning rate or at high magnetic field. These experiments offer a promising way of measuring the principal values of chemical shift anisotropies via spinning side-band analysis in a moderately complex system. General spectral editing in 13C cross-polarization magic-angle spinning (CP/MAS) experiments at high field is achieved by incorporating the total side-band suppression (TOSS) pulse sequence into the standard series of spectral editing pulse sequences. It is confirmed that the relative signal intensity for a certain kind of functional group obtained at different polarization, polarization-inversion and depolarization times is about the same as that obtained at low magnetic field, and that the signal intensity distortion introduced by the TOSS sequence for resonances having different chemical shift anisotropies does not interfere with the spectral editing process. However, quantitative results can only be expected in those cases where full restoration of the intensity of the central band can be achieved by the TOSS sequence. This new strategy at high field is demonstrated by using fumaric acid monoethyl ester as a model compound. A typical application to a Chinese resin is presented, where the relative ratio of each functional group in the aliphatic portion to the total number of aliphatic carbon atoms is determined from only three experimental spectra.

Estrogen-related receptor, hERR1, modulates estrogen receptor-mediated response of human lactoferrin gene promoter

We have shown previously that estrogen-stimulated transcription from the human lactoferrin gene in RL95-2 endometrium carcinoma cells is mediated through an imperfect estrogen response element (ERE) at the 5 -flanking region of the gene. Upstream from the ERE, a DNA sequence (-418 to -378, FP1) was selectively protected from DNase I digestion by nuclear extracts from endometrial and mammary gland cell lines. In this report, using the electrophoresis mobility shift assay, site-directed mutagenesis, and DNA methylation interference analyses, we show that three different nuclear proteins bind to the FP1 region (C1, C2, and C3 sites). The nuclear receptor, COUP-TF, binds to the C2 site. Mutations in the C1 binding region abolish C1 complex formation and reduce estrogen-dependent transcription from the lactoferrin ERE. When the imperfect ERE of the lactoferrin gene is converted to a perfect palindromic structure, the enhancing effect of the C1 binding element for estrogen responsiveness was abolished. We isolated a complementary DNA (cDNA) clone from an RL95-2 expression library that encodes the C1 site-binding protein. The encoded polypeptide maintains 99% amino acid identity with the previously described orphan nuclear receptor hERR1. A 2.2-kilobase mRNA was detected in RL95-2 cells by the newly isolated cDNA but not by the first 180 base pair of the published hERR1 sequence. By Western analysis, a major 42-kDa protein is detected in the RL95-2 nuclear extract with antibody generated against GST-hERR1 fusion protein. Finally, we show that the hERR1 interacts with the human estrogen receptor through protein-protein contacts.

High resolution 1H spectra of powdered solids observed by Hahn echo pulse sequence with magic-angle spinning

The 1H magic-angle spinning (MAS) spectrum for a typical powdered solid is composed of a high resolution component and a broadline component. The high resolution component can be well isolated from the broadline component by the Hahn echo sequence with a long echo time. Compared with CRAMPS experiment, which measures the proton system as a whole, the high resolution echo-MAS method measures only a fraction of the solid, which is usually small at room temperature and quite different from the majority of the solid in both molecular motion and chemical environment. It is shown that for a sample of fumaric acid monoethyl ester, the chemical shifts of the high resolution component are apparently distinguishable from the isotropic chemical shifts of the broadline component in the CRAMPS spectrum as the temperature approaches the melting point. In addition, for a sample of malonic acid, the echo-MAS spectrum is sensitive to moisture and temperature, while its corresponding CRAMPS spectrum is not. It is suggested that the molecules which produce the high resolution component are related to the lattice defects in a solid, including the surface disorder of the polycrystallites, while the molecules that generate the broadline component are located on the rigid lattice of the solid.

Molecular basis of charge movement in voltage-gated sodium channels

Voltage-dependent movement of a sodium channel S4 segment was examined by cysteine scanning mutagenesis and testing accessibility of the residues to hydrophilic cysteine-modifying reagents. These experiments indicate that 2 charged S4 residues move completely from an internally accessible to an externally accessible location in response to depolarization by passage through a short "channel" in the protein. The energetic problems of S4 movement have thus been solved in the same way that may ion channels achieve highly selective and rapid ion permeation through an open pore, by restricting the contact region between the permion and its channel.

Regulation of vascular smooth muscle growth by alpha 1-adrenoreceptor subtypes in vitro and in situ

Rat aorta smooth muscle cells which express all three alpha 1-adrenoreceptors (alpha 1A, alpha 1B and alpha 1D) were used to determine the effect of stimulation of alpha 1-adrenergic receptor subtypes on cell growth. "Combined" alpha 1-adrenoreceptor subtype stimulation with norepinephrine alone caused a concentration-dependent, prazosin-sensitive increase in protein content and synthesis: 48 h of stimulation at 1 microM increased cell protein to 216 +/- 40% of time-matched controls (p = 0.008) and RNA to 140 +/- 13% (p = 0.03); protein synthesis increased to 167 +/- 13% (p < 0.01) after 24 h. Stimulation with norepinephrine plus the selective alpha 1A/alpha 1D antagonist 5-methylurapidil produced greater increases in alpha-actin mRNA (270 +/- 40% at 8 h; p = 0.007), total cell protein (220 +/- 45% at 24 h; p = 0.004), and RNA (135 +/- 8% at 24 h; p = 0.01). These effects were prevented by pretreatment with the selective alpha 1B antagonist chloroethylclonidine. Comparable results were obtained for intact aortae. Stimulation with norepinephrine plus 5-methylurapidil increased (p < 0.05) tissue protein, RNA, dry weight, and alpha-actin mRNA; and as in culture cells, combined stimulation with norepinephrine alone attenuated these responses. By comparison, adventitia (fibroblasts) was unaffected. Removal of endothelial cells had no effect. alpha 1B mRNA decreased by 42 +/- 12% (p = 0.01) in cultured cells during combined alpha 1-adrenoreceptor stimulation and by 23 +/- 8% (p = 0.03) for intact aorta. alpha 1D and beta-actin mRNA were unchanged in cultured cells, aorta media, and adventitia. These findings suggest that prolonged stimulation of chloroethylclonidine-sensitive, possibly alpha 1B-adrenoceptors induces hypertrophy of arterial smooth muscle cells and that stimulation of 5-methylurapidil-sensitive, non-alpha 1B-adrenoreceptors attenuates this growth response.

Evidence for voltage-dependent S4 movement in sodium channels

The mutation R1448C substitutes a cysteine for the outermost arginine in the fourth transmembrane segment (S4) of domain 4 in skeletal muscle sodium channels. We tested the accessibility of this cysteine residue to hydrophilic methanethiosulfonate reagents applied to the extracellular surface of cells expressing these mutant channels. The reagents irreversibly increase the rate of inactivation of R1448C, but not wild-type, channels. Cysteine modification is voltage dependent, as if depolarization extends this residue into the extracellular space. The rate of cysteine modification increases with depolarization and has the voltage dependence and kinetics expected for the movement of a voltage sensor controlling channel gating.

Molecular cloning of the gene encoding RecF, a DNA repair enzyme, from Streptococcus pyogenes

RecF is a component of one of the bacterial DNA repair systems. The start codon of the recF gene of Streptococcus pyogenes resides about 4.4 kb downstream from the end of hasA, the hyaluronan synthase-encoding gene, which is transcribed in the opposite orientation. The deduced 368-amino-acid RecF protein is 43.5% identical to its homolog from Bacillus subtilis. When cloned on a plasmid, recF could complement a S. pyogenes deletion mutant that was sensitive to ultraviolet irradiation and chemical mutagens. This is the first report of a recF sequence from a Gram+ pathogen.

[Chemotherapy through selective pelvic artery catheterization complicated by mural thrombosis]

Through catheter on uterine artery digital subtractive angiography (DSA) intraarterial infusion of chemotherapeutic agents for the treatment of malignant trophoblastic diseases can raise local drug concentration, improve therapeutic results and reduce general side-effects. But mural thrombosis, a possible complication of intra arterial catheterization, should not be overlooked. This study reports 2 cases of mural thrombosis complication in selective pelvic artery catheterization for chemotherapy. The incidence, relevant factors to its occurrence such as technique of catheterization and the duration of catheter retention, as well as measures of prevention and treatment of mural thrombosis are discussed together with review of literature. With regards to prevention of mural thrombosis, stress is being laid on the importance of the technique of catheterization. Preliminary comments on the problem of heparin administration as a preventive measure of mural thrombosis are made.

Sodium channel mutations in paramyotonia congenita exhibit similar biophysical phenotypes in vitro

Mutations in the skeletal muscle voltage-gated Na+ channel alpha-subunit have been found in patients with two distinct hereditary disorders of sarcolemmal excitation: hyperkalemic periodic paralysis (HYPP) and paramyotonia congenita (PC). Six of these mutations have been functionally expressed in a heterologous cell line (tsA201 cells) using the recombinant human skeletal muscle Na+ channel alpha-subunit cDNA hSkM1. PC mutants from diverse locations in this subunit (T1313M, L1433R, R1448H, R1448C, A1156T) all exhibit a similar disturbance in channel inactivation characterized by reduced macroscopic rate, accelerated recovery, and altered voltage dependence. PC mutants had no significant abnormality in activation. In contrast, one HYPP mutation studied (T704M) has a normal inactivation rate but exhibits shifts in the midpoints of steady-state activation and inactivation along the voltage axis. These findings help to explain the phenotypic differences between HYPP and PC at the molecular and biophysical level and contribute to our understanding of Na+ channel structure and function.

[The effect of nutrition support and recombinant growth hormone on body composition and muscle function in postoperative patients]

To determine the effects of nutritional support and recombinant human growth hormone (GH) on body composition and muscle function, we performed a randomized double-blind trial in 18 patients after elective gastrectomy or colectomy. Same amount of calories and amino acids were administered. Daily injection of GH or placebo was given during the first postoperative week. The GH dose was 0.2 IU/kg/d. The study of body composition demonstrated that control subjects lost lean body mass and fat 2.8 +/- 1.46kg and 0.49 +/- 1.3kg, respectively. In contrast, study group subjects lost the fat 0.95 +/- 0.46kg. Hand grip strength fell with time in the control group (P < 0.05). In contrast, grip strength of GH-treated subjects was significantly different from controls (P < 0.01). The study results demonstrated that nutritional support and growth hormone can maintain lean body mass and muscle function in postoperative patients.

Glyceryl-ether monooxygenase (EC 1.14.16.5): nature of the glyceryl-ether lipid substrates in aqueous buffer

The kinetics of inhibition of glyceryl-ether monooxygenase with 6-methyl-5,6,7,8-tetrahydropterin as cofactor (saturating) by the detergent Mega-10 with batyl alcohol and (RS)-3-(1-hexadecyloxy)-2-hydroxypropane-1-phosphocholine as substrates exhibited noncompetitive inhibition with apparent Ki values of 1.74 +/- 0.37 mM and 185 +/- 23 microM, respectively. Inhibition by octadecan-1-ol (with batyl alcohol as substrate in the presence of 2.3 mM Mega-10) was competitive with an apparent Ki value of 765 +/- 80 microM. The critical micelle concentration values of various solutions of Mega-10 were determined and used to show that the active ether-lipid substrates were in micelle form (for a water soluble substrate) or mixed micelle form (for substrates solubilised with Mega-10).

Transcription function of each base pair in the control region of the adenovirus VARNA1 gene

Eighty-seven mutants with single-base substitution in the control region (from -44 to +70) of the adenovirus VARNA1 gene were generated, including nearly every base pair, to examine the role of DNA sequences within this control region for regulating transcription. The effect of these mutations on transcription of the gene was determined in vitro using cytoplasmic S100 extracts from human KB cells. Mutations at -37T, -35A, -29T, -28A, -25C, -18A, -17A, -16A, -13A, -9C, -8C, and -1C in the 5'-flanking region reduced transcription of the gene. Thus two positive regulatory elements, from -44 to -25 and from -18 to +2, interspersed with a putative negative regulatory element were defined. Furthermore, a distinct A-rich purine stretch in the -18 to +2 element was identified. Point mutations in the pyrimidine-rich sequence immediately upstream of the A block promoter element reduced transcription of the gene. Mutations in the GTGG direct repeats of the A block promoter element drastically decreased transcription. Furthermore, mutations that altered the AT-rich sequence immediately downstream of the A block element to become less AT-rich decreased transcription. Mutations of the base pairs at +43C, +45T, and +51A in the inter-block element moderately reduced transcription efficiency of the gene. Mutations at the central four base pairs, GTTC, of the B block palindrome severely affected transcription. These unique sequence motifs and their exact base pairs were proven to be important for regulating transcription of the VARNA1 gene.

The Streptococcus pyogenes hyaluronan synthase: sequence comparison and conservation among various group A strains

We recently cloned the hyaluronan synthase gene (hasA) from Streptococcus pyogenes (DeAngelis et al., J. Biol. Chem. 268, 19181, 1993). Since this is the first glycosaminoglycan synthase gene to be cloned and these enzymes have also not been purified, nothing is yet known at the molecular level about the similarity or relatedness of hyaluronan synthase to other gene products. We found several proteins in the sequence database with substantial similarities to hyaluronan synthase (HasA), including NodC from Rhizobium, DG42 from Xenopus, and the three chitin synthases (Chs) from Saccharomyces. Like HasA, NodC and the Chs proteins all have at least an N-acetylglucosaminyl transferase activity in common and are membrane-associated. The polymerase chain reaction was also used to show that HasA, and probably the two gene operon for hyaluronan biosynthesis (hasA/hasB), is highly conserved among Group A streptococcal strains. In nine strains, isolated from 1917 through 1993, only five silent mutations were detected. The results show that hyaluronan synthase is highly conserved within Group A strains, although another virulence factor, the M protein, varies considerably in these same strains.

The human ecology of tornadoes

This paper offers an empirical test of the impact of human ecological patterns and other known correlates on tornado occurrence. It uses the National Severe Storms Forecast Center's information on tornadoes from 1950 through 1990 and employs ecological data from the U.S. Bureau of the Census and the Environmental Protection Agency. The results show that metropolitan and other urban counties have higher odds of tornado occurrence than rural counties, and that the probability of occurrence of tornadoes increases with increases in the number of previous tornadoes. The paper assesses the meaning of this finding for demographers, atmospheric scientists, engineers, and disaster managers.

Insertional editing in mitochondria of Physarum

RNA produced from a number of genes on the mitochondrial (mt) DNA of Physarum polycephalum have nucleotides inserted at specific sites in their sequence. These insertions are spaced at approximately 25 nucleotide intervals and create open reading frames in mRNA and functional structure in tRNAs and rRNAs. Although most of the insertions at a site are single cytidines; single uridines and certain dinucleotides containing adenosine and guanosine as well as cytidine and uridine are also occasionally inserted at certain sites. This mixed nucleotide insertional RNA editing is unique among currently characterized editing systems.

COUP-TF acts as a competitive repressor for estrogen receptor-mediated activation of the mouse lactoferrin gene

We previously demonstrated that the estrogen response module (mERM) of the mouse lactoferrin gene, which contains an overlapping chicken ovalbumin upstream promoter transcription factor (COUP-TF)- and estrogen receptor-binding element, is responsible for estrogen induction. In this report we show that COUP-TF represses the mERM response to estrogen stimulation. Mutation and deletion of the COUP-TF-binding element or reduction of the endogenous COUP-TF increases mERM estrogen responsiveness. Likewise, overexpression of the COUP-TF expression vector blocked the estrogen-stimulated response of mERM in transfected cells. The molecular mechanism of this repression is due to the competition between COUP-TF and the estrogen receptor for binding at identical contact sites in the overlapping region of the mERM. Our results indicate that two members of the steroid-thyroid receptor superfamily work in concert to modulate lactoferrin gene expression.

[The kinetic observation of serum ketone body levels in surgical patients receiving MCT or LCT emulsions]

The changes of serum beta-hydroxybutyrate concentrations in patients after receiving medium chain triglycerides (MCT) or long chain triglycerides (LCT) were studied. The patients were divided into two groups: in Group 1, the dose of fat was 0.14 g/kg.h for fat emulsion clearance test: and in Group 2, the dose was 0.06 g/kg.h for total parenteral nutrition (TPN) support. The beta-hydroxybutyrate concentrations were estimated by an enzymatic method using Sigma's beta-hydroxybutyrate kit (Sigma Diagnostics, MO 63178, USA). The normal range of beta-hydroxybutyrate concentration in 30 healthy Chinese subjects was 1.04 +/- 1.42 mg/dl (range 0-3.88 mg/dl). In Group 1, we found that the concentrations of beta-hydroxybutyrate rose steadily after fat emulsion infusion. The concentrations in the medium chain triglyceride group were higher than those in long chain triglyceride group. The elevated concentrations of beta-hydroxybutyrate gradually returned to normal levels when the emulsion infusion was stopped. In Group 2, the concentrations of beta-hydroxybutyrate in the patients were within the normal range.

Development of human ABO blood group A antigen on Escherichia coli Y1089 and Y1090

Studies by other workers have shown that some strains of Escherichia coli have surface antigens analogous to the human blood group ABH antigens, and that these are carbohydrates associated with membrane lipopolysaccharides. This study has demonstrated that E. coli strains Y1089 and Y1090 possess the H antigen, which can be converted to the A antigen by incubation with A-transferase (N-acetyl-galactosaminyl transferase) and A-sugar (UDP-N-acetyl-galactosamine). Such cells will then form mixed agglutinates with human A red cells and human polyclonal (but not mouse monoclonal) anti-A antibodies. E. coli Y1089 and Y1090 have endogenous enzymes that use the A-sugar (in the absence of A-transferase) to produce a variant A antigen. Cells expressing this variant antigen adsorb anti-A antibodies but do not participate in mixed agglutination with human group A red cells. It is estimated that E. coli Y1089 and Y1090 possess approximately 5000 H epitopes per cell that can be converted to A epitopes.