Prediction of muscle strength and postoperative function after knee flexor muscle resection for soft tissue sarcoma of the lower limbs

INTRODUCTION

Oncological margins and prognosis are the most important factors for operative planning of soft tissue sarcomas, but prediction of postoperative function is also necessary. The purpose of this study was to predict the knee flexion strength and postoperative function after knee flexor muscle resection for soft tissue sarcoma of the lower limbs.

MATERIALS AND METHODS

Seventeen patients underwent knee flexor muscle resection for soft tissue sarcoma of the lower limbs between 1991 and 2015. The type of resected muscles was surveyed, knee flexion strength (ratio of affected to unaffected side) was evaluated using the Biodex System isokinetic dynamometer, and differences between the type of resected muscles were examined. The Musculoskeletal Tumor Society (MSTS) score, Toronto Extremity Salvage Score (TESS), European Quality of Life-5 Dimensions (EQ-5D), and Short Form 8 (SF-8) were used to assess postoperative function and examine correlations with flexion strength. The cutoff value for flexion strength to predict good postoperative results was calculated by a receiver operating characteristic (ROC) curve and Fisher's exact test.

RESULTS

Median flexion strength decreased in the resection of sartorius (97.8%), gracilis (95.4%), gastrocnemius (85.2%; interquartile range (IQR): 85.0-86.2), medial hamstrings (semimembranosus and semitendinosus, 76.2%; IQR: 73.3-78.0), lateral hamstrings (long and short head of biceps femoris, 66.1%; IQR: 65.9-70.4), and bilateral hamstrings (27.3%; IQR: 26.6-31.5). A significant difference was observed between lateral and bilateral hamstrings resection (P=0.049). Flexion strength was associated with lower functional scales (MSTS score, P=0.021; TESS, P=0.008; EQ-5D, P=0.034). Satisfactory function was obtained at a flexion strength cutoff value of 65.7%, and strength remained above the cutoff value up to unilateral hamstrings resection.

DISCUSSION

Greater knee flexor muscles resection can result in functional deficits that are associated with decreased flexion strength. If continuity of unilateral hamstrings is maintained, good postoperative results can be expected.

LEVEL OF EVIDENCE

IV, retrospective study.

Knee extension strength and post-operative functional prediction in quadriceps resection for soft-tissue sarcoma of the thigh

Objectives

Our objective was to predict the knee extension strength and post-operative function in quadriceps resection for soft-tissue sarcoma of the thigh.

Methods

A total of 18 patients (14 men, four women) underwent total or partial quadriceps resection for soft-tissue sarcoma of the thigh between 2002 and 2014. The number of resected quadriceps was surveyed, knee extension strength was measured with the Biodex isokinetic dynamometer system (affected side/unaffected side) and relationships between these were examined. The Musculoskeletal Tumor Society (MSTS) score, Toronto Extremity Salvage Score (TESS), European Quality of Life-5 Dimensions (EQ-5D) score and the Short Form 8 were used to evaluate post-operative function and examine correlations with extension strength. The cutoff value for extension strength to expect good post-operative function was also calculated using a receiver operating characteristic (ROC) curve and Fisher’s exact test.

Results

Extension strength decreased when the number of resected quadriceps increased (p < 0.001), and was associated with lower MSTS score, TESS and EQ-5D (p = 0.004, p = 0.005, p = 0.006, respectively). Based on the functional evaluation scales, the cutoff value of extension strength was 56.2%, the equivalent to muscle strength with resection of up to two muscles.

Conclusion

Good post-operative results can be expected if at least two quadriceps muscles are preserved.

Cite this article: A. Tanaka, Y. Yoshimura, K. Aoki, M. Kito, M. Okamoto, S. Suzuki, T. Momose, H. Kato. Knee extension strength and post-operative functional prediction in quadriceps resection for soft-tissue sarcoma of the thigh. Bone Joint Res 2016;5:232–238. DOI: 10.1302/2046-3758.56.2000631.

Clinical outcome of deep-seated atypical lipomatous tumor of the extremities with median-term follow-up study

AIMS

There is no consensus on the best surgical treatment for deep-seated atypical lipomatous tumor (ALT) of the extremities; furthermore, the appropriate duration for follow-up observation remains unclear. We investigated clinical and functional median-term outcomes in the primary operations for ALT of the extremities in order to find its best treatment methods and observation periods.

METHODS

From 1996 to 2009, we diagnosed 41 patients with deep-seated ALT of the extremities. Wide resection was performed on 11 patients and marginal resection was performed on 30 patients. The minimum follow-up was 5 years (median, 8.5; range, 5-17.4). Patients were evaluated for their local recurrence, dedifferentiation, and post-operative function using the ISOLS/MSTS scoring system.

RESULTS

Recurrence and dedifferentiation rates were both 0% for the wide resection group, while the rates were 23% (7/30) and 3% (1/30) for the marginal resection group, respectively. Median duration before recurrence was 7.2 years (range, 4.0-14.2). Local recurrence-free survival rate was significantly higher in the wide resection group (P = 0.013). In the marginal resection group, 10% (3/30) of the cases showed residual tumor. The localization of these tumors was all intermuscular. The ISOLS/MSTS scores were 98% (range, 90-100) for wide resection and 99% (range, 93-100) for marginal resection, with no statistical difference (P = 0.694). No ALT-related deaths occurred during the observation period.

CONCLUSIONS

In addition to long-term (at least 8 years) of continuous observation, a wide resection is necessary in order to prevent recurrence, dedifferentiation, and residual tumor.

Discovery, structure–activity relationship study, and oral analgesic efficacy of cyproheptadine derivatives possessing N-type calcium channel inhibitory activity

Antiallergic drug cyproheptadine (Cyp) is known to have inhibitory activities for L-type calcium channels in addition to histamine and serotonin receptors. Since we found that Cyp had an inhibitory activity against N-type calcium channel, Cyp was optimized to obtain more selective N-type calcium channel blocker with analgesic action. As a consequence of the optimization, we found 13 with potent N-type calcium channel inhibitory activity which had lower inhibitory activities against L-type calcium channel, histamine (H1), and serotonin (5-HT2A) receptors than those of Cyp. 13 showed an oral analgesic activity in rat formalin-induced pain model.

Biological function of the pld gene product that degrades -poly-l-lysine in Streptomyces albulus

Epsilon-poly-L-lysine (epsilon-PL) is one of the few naturally occurring biopolymers and is characterized by a peptide bond between the alpha-carboxyl and epsilon-amino groups. Previously, we purified and characterized the epsilon-PL-degrading enzyme (Pld) from Streptomyces albulus, which is an epsilon-PL producer, and this enzyme was expected to confer self-resistance to the epsilon-PL produced by the organism itself. The gene encoding Pld was cloned based on the N-terminal amino acid sequence determined in this study, and a sequencing analysis revealed eight open reading frames (ORFs), i.e., ORF1 to ORF8 in the flanking region surrounding the pld gene (present in ORF5). To investigate the biological function of Pld, we constructed a knockout mutant in which the pld gene is inactivated. Studies on epsilon-PL susceptibility, epsilon-PL-degrading activity, and epsilon-PL productivity demonstrated that the pld gene does play a partial role in self-resistance and that S. albulus was found to produce other epsilon-PL-degrading enzyme(s) in addition to Pld. To the best of our knowledge, this is the first report on a self-resistance gene for a biopolymer possessing antibacterial activity.

Structure–activity relationship study of 1,4-dihydropyridine derivatives blocking N-type calcium channels

Cilnidipine is a 1,4-dihydropyridine derived L/N-type calcium channel dual blocker possessing neuroprotective and analgesic effects which are related to its N-type calcium channel inhibitory activity. In order to find specific N-type calcium channel blockers with the least effects on cardiovascular system, we performed structure-activity relationship study on APJ2708, which is a derivative of cilnidipine, and found a promising N-type calcium channel blocker 21b possessing analgesic effect in vivo with a 1600-fold lower activity against L-type calcium channels than that of cilnidipine.

Shielding the front-strand beta 3 of the von Willebrand factor A1 domain inhibits its binding to platelet glycoprotein Ibalpha

Platelet adhesion to damaged vessel wall and shear-induced platelet aggregation necessitate binding of the von Willebrand factor (VWF) A1 domain to platelet GPIbalpha. Blocking this interaction represents a promising approach to the treatment of arterial thrombosis. Comparison of amino acid sequences of the VWF A1 domain in several species, expressing VWF recognized by the blocking monoclonal antibody AJvW-2, suggested 9 residues (His563, Ile566, Asp570, Ala581, Val584, Ala587, Arg616, Ala618, and Met622) to contribute to the epitope for AJvW-2 or to be part of the GPIbalpha-binding site. Glutathione-S-transferase (GST)-human VWF A1 fusion proteins, in which these amino acids were mutated to their murine counterparts, were tested for their capacity to bind AJvW-2 or heparin, to interfere with botrocetin- or ristocetin-mediated VWF binding to GPIb, or to induce flow-dependent platelet tethering in a perfusion chamber. Thus, mutations His563Arg, Ile566Leu, Asp570Ala, and Ala587Thr, clustered on the outer surface of the A1 domain, dramatically impaired binding of AJvW-2 to A1. The His563Arg, Ile566Leu, and Asp570Ala mutations also impaired the binding of heparin, which competes with AJvW-2 for binding to A1. Perfusion studies revealed that His563, Ile566, Asp570, Arg616, and Ala618 take part in GPIbalpha binding, their mutation-impairing platelet recruitment. In agreement with the surface distribution of VWF type 2M mutations, this study demonstrates overlapping of the epitope for AJvW-2 and the GPIbalpha-binding site, located around the front pocket of the A1 domain and defined by strands beta3, beta4, and helix alpha3, and it provides a mechanistic basis for VWF neutralization by this antibody.

Construction of engineered CHO strains for high-level production of recombinant proteins

We constructed engineered CHO strains that can be used for high-level production of foreign proteins by gene-targeting. After transfecting dihydroforate reductase (DHFR)-deficient CHO cells with a plasmid carrying a loxP-green fluorescent protein (GFP) fusion gene and a DHFR gene, we screened colonies by fluorescent intensity. We selected 16 clones that expressed high levels of GFP and carried one copy of the plasmid in their chromosomes and treated them with methotrexate (MTX) to examine their ability for DHFR-mediated gene amplification. Two clones, MK1 and MK2, showed increased GFP expression upon gene amplification. In those clones, the loxP-GFP gene was integrated at a transcription-active, DHFR-mediated, gene-amplifiable locus in the chromosomes. A gene-targeting vector, carrying a loxP-fused hygromycin-resistance gene, was constructed to target desired genes in chromosomal loxP by Cre recombinase-mediated site-specific recombination. Using this cell-vector system, we could reproducibly obtain high producers of recombinant proteins by gene-targeting and gene amplification. In human monoclonal antibody production, after gene-targeting of loxP in MK2 and gene amplification with MTX, the MTX-resistant colonies showed high levels of antibody production. The most productive clone was able to produce 160 mg/l in 7 days in a low-protein medium in a spinner-flask.

Gelastic seizures in clusters in a case of West syndrome after perinatal hypothalamic hemorrhage

We describe a 4-month-old Japanese infant with West syndrome with gelastic seizures in clusters. Smile developed around 3 months and gradually increased in frequency and intensity. Positron emission tomography showed hypoperfusion in bilateral hypothalamus. Interictal electroencephalogram (EEG) showed hypsarrythmia. Simultaneous video/EEG monitoring was performed. At first, a smile-like episode developed every several seconds, gradually increased to an abrupt flexion of the neck and extremities, and gradually decreased to a smile-like episode at the end. Ictal EEG revealed desynchronization. ACTH was effective. Smiles are common emotional responses in infancy. However, EEG and neuroimaging should be considered in a case of perinatal asphyxia and delayed development.

Reduction by phytate-reduced soybean beta-conglycinin of plasma triglyceride level of young and adult rats

This study examined the effects of soybean beta-conglycinin, from which phytate was mostly removed, on the plasma lipids in young and adult rats. Male Wistar young (6 week-old) and adult (21 week-old) rats were fed high cholesterol diets containing 20% casein, soy protein isolate (SPI), or soybean beta-conglycinin for 10 days. In young rats, although the food intake of the beta-conglycinin group was higher than those of the casein and SPI groups, the weight gain was significantly lower than those of the other groups. However, in adult rats, the weight gain was not different among the groups. In young and adult rats, relative liver weights of SPI and beta-conglycinin groups were significantly lower than that of the casein group, and the degree of the reduction was more marked in the beta-conglycinin group than in the SPI group. In young rats, the plasma triglyceride level was significantly lower in the SPI and beta-conglycinin groups than that in the casein group. In addition, the plasma triglyceride level of the beta-conglycinin group was significantly lower than that of the SPI group. Plasma total cholesterol levels of the SPI and beta-conglycinin groups were significantly lower than that of the casein group. However, there was little difference in the lowering effect between SPI and beta-conglycinin. These results indicate that soybean beta-conglycinin may have lowering functions not only on plasma total cholesterol level, but also on plasma triglyceride level.

A multidisciplinary approach to the treatment of malignant pelvic bone tumors: results with eight consecutive patients

The prognosis for malignant pelvic bone tumors is worse than that for malignant bone tumors of the extremities because definitive surgery in the pelvis is often difficult to accomplish. The results for eight patients who were treated consecutively with a multidisciplinary approach, from 1990, were analyzed. The histologic diagnosis was osteosarcoma in five patients, chondrosarcoma in two, and Ewing's sarcoma in one. Five lesions arose in the ilium and three in the pubis. The extraosseous tumors decreased in size and/or were encapsulated as a result of preoperative chemotherapy in six patients, four of these achieving a wide surgical margin. With respect to tumor location and surgical margin, all five lesions in the ilium involved the sacrum, four of these being resected with an inadequate margin. The three lesions in the pubis were resected with an adequate margin. Local recurrence was observed in two patients who had been treated with an inappropriate margin. During the period between 18 and 57 months after the first operation, five patients were continuously free of disease and one was still alive but had lung metastases. Our results indicate that a patient's chances of definitive surgery may be enhanced by a multidisciplinary approach, although the management of sacroiliac involvement remains challenging.

Novel method using phytase for separating soybean beta-conglycinin and glycinin

A novel method for separating soybean beta-conglycinin and glycinin from defatted soymilk by a phytase treatment was developed. Phytase was added to defatted soymilk (1000FYT/100 g of protein) at pH 6.0, and the mixture incubated for 1 h at 40 degrees C. This procedure separated beta-conglycinin and glycinin without needing a reducing agent or cooling into the soluble and insoluble fractions, respectively. Simultaneously, most of the phytate in both proteins was removed.

3-Hydroxy-3-methylglutaryl Coenzyme A Reductase Is Sterol-Dependently Cleaved by Cathepsin L-Type Cysteine Protease in the Isolated Endoplasmic Reticulum

We have recently shown that 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, an endoplasmic reticulum (ER) membrane protein, is degraded in ER membranes prepared from sterol pretreated cells and that such degradation is catalyzed by a cysteine protease within the reductase membrane domain. The use of various protease inhibitors suggested that degradation of HMG-CoA reductase in vitro is catalyzed by a cathepsin L-type cysteine protease. Purified ER contains E-64-sensitive cathepsin L activity whose inhibitor sensitivity was well matched to that of HMG-CoA reductase degradation in vitro. CLIK-148 (cathepsin L inhibitor) inhibited degradation of HMG-CoA reductase in vitro. Purified cathepsin L also efficiently cleaved HMG-CoA reductase in isolated ER preparations. To determine whether a cathepsin L-type cysteine protease is involved in sterol-regulated degradation of HMG-CoA reductase in vivo, we examined the effect of E-64d, a membrane-permeable cysteine protease inhibitor, in living cells. While lactacystin, a proteasome-specific inhibitor, inhibited sterol-dependent degradation of HMG-CoA reductase, E-64d failed to do so. In contrast, degradation of HMG-CoA reductase in sonicated cells was inhibited by E-64d, CLIK-148, and leupeptin but not by lactacystin. Our results indicate that HMG-CoA reductase is degraded by the proteasome under normal conditions in living cells and that it is cleaved by cathepsin L leaked from lysosomes during preparation of the ER, thus clarifying the apparently paradoxical in vivo and in vitro results. Cathepsin L-dependent proteolysis was observed to occur preferentially in sterol-pretreated cells, suggesting that sterol treatment results in conformational changes in HMG-CoA reductase that make it more susceptible to such cleavage.

Primary extracranial meningioma of the foot: a case report

We present a rare case of primary extracranial meningioma in a 36-year-old man, who had a solitary multinodular mass located in the plantar muscle of the foot. The histology of specimens from simple excision was typical of meningioma, showing bland spindle cell proliferation with a whorl pattern. Immunohistochemical analysis demonstrated that the tumor cells showed diffuse and strong positivity for epithelial membrane antigen as well as moderate reactivity for cytokeratin and vimentin. Ultrastructurally, the tumor cells were characterized by thin bipolar cytoplasmic processes and joined by multiple small desmosomes. There were frequent pinocytotic vesicles and a distinct external lamina on the cell surface. These findings suggest that this primary ectopic meningioma, arising in the soft tissue, may have been derived from perineurial cells of the peripheral nerve, but was morphologically distinguishable from perineurioma. Primary extracranial meningioma should be included in the differential diagnosis of soft-tissue spindle cell tumors, especially those of peripheral nerve origin.

Accumulation and degradation in the endoplasmic reticulum of a truncated ER-60 devoid of C-terminal amino acid residues

The accumulation and degradation in the endoplasmic reticulum (ER) of a truncated ER-60 protease, from which the C-terminal 89 amino acid residues have been deleted (K 417 ochre), was examined. K 417 ochre overexpressed in COS-1 cells is not secreted into the medium, but accumulates as insoluble aggregates in non-ionic detergent without degradation in unusual clump membrane structures. K 417 ochre, stably expressed, forms soluble aggregates in non-ionic detergent and is distributed in the reticular structures of ER. Under these conditions, K 417 ochre is not secreted into the medium but is degraded with a half-life time of more than 8 h. Since K 417 ochre/C all S, in which all the Cys residues of K 417 ochre are replaced by Ser, also forms aggregates, an inter-disulfide bond appears unnecessary for aggregation. In both types of aggregates, Ig heavy chain binding protein, calnexin, glucose regulated protein 94, calreticulin, ERp72, and protein disulfide isomerase are scarcely found. Since degradation of the stably expressed K 417 ochre was not inhibited by lactacystin, leupeptin, NH(4)Cl, or cytocharasin B, but was inhibited by N-acetyl-leucyl-leucyl-norleucinal, the self-aggregated abnormal protein in the lumen of ER is assumed to be degraded by an unknown protease system other than proteasome, lysosome or autophagy.

Catalytic cysteine residues of ER-60 protease

ER-60 protease contains two CGHC motifs that appear to include an active site cysteine residue(s). Its proteolytic activity was lost with a double mutation of the C-terminal cysteines of the two motifs to alanine, but not with a single mutation of the C-terminal cysteine of either of the motifs to alanine. This suggests that these C-terminal cysteines independently constitute the catalytic active site. A mutation of both histidine residues in the two CGHC motifs to serine did not abolish the proteolytic activity, suggesting these histidine residues in the CGHC motifs do not constitute the catalytic dyad of ER-60 protease.

Safety assessment of transgenic potatoes with soybean glycinin by feeding studies in rats

Feeding studies of transgenic potatoes with native and designed soybean glycinins in rats were done for four weeks. The designed glycinin has four additional methioninyl residues in the middle of the glycinin molecule. Rats were divided into four groups fed (I) only a commercial diet, (II) the diet plus non-transgenic potatoes, (III) the diet plus transgenic potatoes with native glycinin, and (IV) the diet plus transgenic potatoes with designed glycinin. Rats were fed 2,000 mg/kg-weight potatoes every day by oral administration. During the period tested, rats in each group (groups II, III, and IV) grew well without marked differences in appearance, food intake, body weight, or in cumulative body weight gain. No significant differences were also found in blood count, blood composition, and in internal organ weights among the rats after feeding potatoes (groups II, III, and IV) for four weeks. Necropsy at the end of experiment indicated neither pathologic symptoms in all rats tested nor histopathological abnormalities in liver and kidney. Judging from these results, the transgenic potatoes with glycinins are confirmed to have nearly the same nutritional and biochemical characteristics as non-transgenic one.

Purification and characterization of diacylglycerol lipase from human platelets

Diacylglycerol lipase (DGL) was solubilized from human platelet microsomes with heptyl-beta-D-thioglucoside, and purified to homogeneity on SDS-PAGE using a combination of chromatographic and electrophoretic methods. The molecular mass of the purified DGL was estimated to be 33 kDa. Its apparent pI was pH 6.0, as determined by Immobiline isoelectro-focusing. The enzymatic activity of the partially purified DGL was investigated in the presence of a variety of inhibitors and reagents, as well as its pH and calcium dependence. Thiol reagents such as p-chloromercurubenzoic acid (pCMB), N-ethylmaleimide (NEM), and HgCl2 inhibited the activity, while dithiothreitol (DTT) and reduced glutathione (GSH) enhanced it. In addition, the enzymatic activity was inhibited by two serine blockers, phenylmethylsulfonyl fluoride (PMSF) and diisopropyl fluorophosphate (DFP), and by a histidine modifying reagent, p-bromophenacyl bromide (pBPB). These results suggest that cysteine, serine and histidine residues are required for the enzymatic activity of DGL. DGL was optimally active in the pH range of 7-8 and its activity did not change significantly in the presence of various calcium concentrations, even in the presence of 2 mM EGTA. This indicates that DGL can hydrolyze substrates with a basal cytosolic free Ca2+ level in the physiological pH range. A DGL inhibitor, RHC-80267, inhibited DGL activity in a dose-dependent manner with an IC50 (the concentration required for 50% inhibition) of about 5 microM. Unexpectedly, several phospholipase A2 (PLA2) inhibitors were potent inhibitors of DGL activity (IC50<5 microM), suggesting that the catalytic mechanisms of DGL and PLA2 may be similar. Finally, we show that DGL activity was inhibited by 2-monoacylglycerols (2-MGs), the reaction products of this enzyme. Among the three 2-MGs tested (2-arachidonoyl glycerol, 2-stearoyl glycerol, and 2-oleoyl glycerol), 2-arachidonoyl glycerol was the most potent inhibitor.

A case of acquired zinc deficiency in a mature breast-fed infant

We describe a 5-month-old Japanese infant with zinc deficiency, who was exclusively breast-fed and showed improvement after zinc supplement was administered. His serum zinc level and the zinc content of breast milk from his mother were extremely low, although the mother's serum zinc level was within normal limits. Zinc deficiency would not be latently uncommon in a mature breast-fed infant.

Three types of voltage-dependent calcium currents developing in cultured human neuroblastoma cells

Voltage-dependent calcium currents (ICa), which developed in cultured human neuroblastoma cells (NB-I), were studied using a whole-cell recording technique. Three types (T-, N- and L-type) of ICa were identified based on their biological and pharmacological properties. The T-type ICa was observed in about 60% of the cells from day 2 to day 12 and in about 20% after day 14. Likewise, the amplitude gradually decreased from -61.7 +/- 10.1 pA on day 2 to -18.3 +/- 9.1 pA on day 18. The N-type ICa appeared on day 6, with the number of cells exhibiting this current increasing up to 90.9% (-73.4 +/- 16.0 pA) on day 14 and immediately decreasing thereafter. The L-type ICa was observed in 50.0% of the cells on day 2, increasing to 84.6% of the cells on day 6 and remaining thereafter, while the amplitude gradually increased from -37.8 +/- 14.0 pA on day 2 to -158.8 +/- 22.8 pA on day 18, and decreased thereafter. These findings indicate that the expression of the voltage-dependent Ca2+ channels is strongly regulated by the developmental stage of the cell.

Induction of apoptosis in cultured colon cancer cells by transfection with human interferon beta gene

The growth of SW480 colon cancer cells following the transfection with the human interferon beta (hIFNbeta) gene entrapped in cationic multilamellar liposomes was effectively inhibited, but not that of the cells transfected with the gene from which the secretion signal sequence of hIFNbeta had been deleted. The amount of hIFNbeta secreted in the medium from SW480 cells transfected with hIFNbeta gradually increased and became maximum 3 days after the transfection, but no hIFNbeta was detected in the medium of the cells transfected with the secretion signal-deleted hIFNbeta. These findings indicate that the growth inhibition of SW480 cells after the transfection with hIFNbeta was caused by hIFNbeta secreted from the transfected cells. At that time, SW480 cells were induced to undergo apoptosis, which was identified by morphological aspects, viz., chromatin condensation, nuclear segmentation, and nucleosomal DNA fragmentation. The hIFNbeta-induced apoptosis was found to be linked to the activation of caspases 3 and 8 as evidenced by immunoblot, enzymological, and cell death inhibition analyses.

Autodegradation of protein disulfide isomerase

Protein disulfide isomerase (PDI) and its degradation products were found in HepG2, COS-1, and CHO-K1 cells. Whether or not the products were formed through autodegradation of PDI was examined, since PDI contains the CGHC motif, which is the active center of proteolytic activity in ER-60 protease. Commercial bovine PDI was autodegraded to produce a trimmed PDI. In addition, human recombinant PDI also had autodegradation activity. Mutant recombinant PDIs with CGHC motifs of which cysteine residues were replaced with serine or alanine residues were prepared. However, they were not autodegraded, suggesting the cysteine residues of motifs are necessary for autodegradation.

Quality and safety evaluation of genetically engineered rice with soybean glycinin: analyses of the grain composition and digestibility of glycinin in transgenic rice

The composition of nutritionally and physiologically important molecules in transgenic rice with the soybean glycinin gene was determined and compared with that of a non-transgenic control. Except for the levels of protein, amino acids and moisture, no marked differences were found between the two kinds of rice. The protein content of the transgenic rice was about 20% higher than the control (control, 6.5 g/100 g; transgenic, 8.0 g/100 g) with a concomitantly lower moisture content. This increased protein content mainly resulted from the increased glycinin expressed in the transgenic rice, and the protein was susceptible to gastric and intestinal digestion juices. In parallel with the increased protein content, some important amino acids lacking in quantity in normal rice were replenished.

[Chemotherapy for pulmonary metastases of soft tissue sarcoma]

The role and value of chemotherapy for soft tissue sarcomas remain unclear. Seventeen patients with pulmonary metastatic soft tissue sarcomas underwent treatment with chemotherapy, and the clinical efficacy and prognosis were studied. Six patients with synovial sarcomas, 4 with malignant fibrous histiocytomas, 4 with neurosarcomas, and the remaining 3 patients with leiomyosarcoma, extraskeletal osteosarcoma, and extraskeletal chondrosarcoma, were studied. Cases with small round cell sarcomas were excluded. The chemotherapy agents were ifosfamide in 10 cases, combination of ifosfamide and adriamycin in 5 cases, or cisplatin and adriamycin in 2 cases. Of the 17 patients, seven had partial responses radiographically and five had pulmonary metastases from synovial sarcoma. Eight patients underwent resection of pulmonary metastases following chemotherapy, and they were found to be residual tumor cells histologically. Twelve of the patients died of disease at 6-108 months (median, 30 months) from the time of the initial therapy, and five patients have survived from 1-53 months (median, 30 months). The absolute three-year survival rate, according to the Kaplan-Meier method, for all 17 patients was 39%. In the two cases with no change and progressive disease, all patients were dead within 2 years, while in the seven partial response cases, two patients were dead, four were alive with pulmonary metastases, and only one case was disease-free at this writing. The survival rate for patients with partial response was significantly higher than for patients with no response. Although the cure rate of pulmonary metastatic soft tissue sarcomas is still low, the combination of chemotherapy and surgery has been shown to result in prolonged survival.

Safety assessment of genetically engineered food: detection and monitoring of glyphosate-tolerant soybeans

A detection technique for the genetically engineered food, glyphosate-tolerant soybean (GTS), was designed. Commercial soybeans imported from North America were cultured in pots and genomic DNA was isolated from their leaves. To detect the genes, promoter and terminator, involved in the expression of glyphosate tolerance, PCR was done using the genomic DNA and chemically synthesized primers specific to the genes. DNAs with predicted sizes were amplified and confirmed by DNA sequencing to be the genes responsible for the expression of glyphosate tolerance. Glyphosate-tolerant soybeans were found to form approximately 1.1% of the commercial soybeans, when commercially available soybeans were cultivated and number of soybeans resistant to glyphosate was found. This level is somewhat lower than an estimated value announced officially on the basis of the cultivation area of the glyphosate-tolerant soybeans.

Effect on colon cancer cells of human interferon-beta gene entrapped in cationic multilamellar liposomes

When cultured cells of human colon cancer cell line SW480 were transfected with human interferon-beta (hIFN-beta) gene by means of cationic multilamellar liposomes, the endogenously produced hIFN-beta exhibited a remarkable anti-proliferative effect on the cells, which was more effective than that of exogenously added hIFN-beta. This effect lasted for several days, and was blocked completely by the addition of sufficient amounts of anti-hIFN-beta antibody. From experiments using a transwell plate and an infusion pump, we found that endogenously produced hIFN-beta acted effectively on the cells around the transfectants and that the growth-inhibitory effect was totally retained upon continuous dilution of the medium. These data indicate that hIFN-beta expressed endogenously by transfer of its gene acted on these cancer cells mainly in a paracrine manner. Although the transfection with hIFN-gamma gene also revealed a definite growth-inhibitory effect on the same tumor cells, the extent was less than that of hIFN-beta gene.

Functions of characteristic Cys-Gly-His-Cys (CGHC) and Gln-Glu-Asp-Leu (QEDL) motifs of microsomal ER-60 protease

The human ER-60 protease cDNA was expressed in Escherichia coli BL21 (DE3) cells using the pET-20b(+) T7 promoter. The recombinant ER-60 protease was obtained in a water-soluble form and purified through four sequential chromatographies. The ER-60 protease contains two CGHC motifs. When an alanine residue was substituted for the N-terminal cysteine residue in both motifs, the protease activity was not lost. However, when the C-terminal cysteine residue in both motifs was replaced by a serine residue, the cysteine protease activity, which was inhibited by p-chloromercuribenzoic acid (pCMB) but not by diisopropyl fluorophosphate (DFP), changed to serine protease activity, which was inhibited by DFP but not by pCMB. These results indicate that the C-terminal cysteine residue(s) of the CGHC motifs may constitute the active site(s) of ER-60 protease. The ER-60 protease has a C-terminal QEDL sequence, which was proved to serve as an ER-retention signal by deletion of the QEDL sequence. However, because QEDL could not serve as the ER-retention signal for protein disulfide isomerase or ERp72, it is suggested that amino acid residue(s) of ER-60 protease, other than the QEDL sequence itself, is complimentarily responsible for the ER retention of this protein.

Apolipoprotein B is intracellularly associated with an ER-60 protease homologue in HepG2 cells

Two ALLN (N-acetyl-leucyl-leucyl-norleucinal)-sensitive endoplasmic reticulum (ER)-localized proteases (ER-60 and ER-72) were recently purified from rat liver. We used an antibody to rat ER-60 to investigate the possible role of this protease in apolipoprotein B (apoB) degradation. First, immunoprecipitation and immunoblotting experiments with the anti-rat ER-60 antibody suggested that HepG2 cells contain a homologue of ER-60 with an approximate molecular mass of 58-60 kDa. The ER-60 homologue was mostly associated with the luminal contents of HepG2 microsomes. Evidence from co-immunoprecipitation and cross-linking experiments appear to suggest that the ER-60 homologue in HepG2 cells is associated with apoB intracellularly. A small pool of apoB was recovered when HepG2 lysates were subjected to immunoprecipitation with anti-rat ER-60 antibody followed by a second immunoprecipitation with anti-apoB antibody. Furthermore, cross-linking of permeabilized cells with dithiobis(succinimidylpropionate) further demonstrated association of apoB with the ER-60 homologue in HepG2 cells. Three polypeptides with molecular masses of 78, 66, and 50 kDa were consistently found to be associated with apoB as well as the 58-kDa ER-60 homologue. The 78-kDa protein associated with both apoB and ER-60 appeared to represent immunoglobulin heavy chain-binding protein (BiP) based on immunoprecipitation with a monoclonal antibody. Cross-linking and immunoblotting experiments suggested the association of the 78-kDa BiP with both the 58-kDa ER-60 homologue as well as the 550-kDa apoB. In summary, the data suggests that HepG2 cells contain a 58-kDa protein which is homologous to the rat liver ER-60 in size, antigenecity, and intracellular localization. The ER-60 homologue in HepG2 cells appears to be closely associated with apoB, as well as other proteins possibly representing ER chaperones such as BiP. We hypothesize that the ER-60 homologue may be involved in the degradation of apoB in the ER lumen of HepG2 cells.

Severe myoclonic epilepsy in infancy: evolution of seizures

Changes in seizure type of severe myoclonic epilepsy (SME) in infancy were reviewed retrospectively in 14 patients (11 males and 3 females) who were followed-up to the age of 7 years or more. The observation period ranged from 5 to 16 years with a mean of 10 years. During the follow-up, three or four types of seizures were seen per patient, but the pattern of appearance and disappearance of each seizure type varied considerably among the patients. Tonic-clonic convulsion, either generalized or unilateral, was seen most consistently through the entire course, and it continued to the end of follow-up in 11 patients (79%). On the contrary, myoclonic seizure, complex partial seizure, and atypical absence often disappeared and reappeared repeatedly during the course. In SME, seizure symptoms varied widely among patients in comparison with other neurological symptoms, and the most consistent core seizure type was tonic-clonic convulsions.

Selective incorporation of polyunsaturated fatty acids into organelle phospholipids of animal cells

The selective incorporation of linoleic (18:2(n-6)) and docosahexaenoic (22:6(n-3)) acids into phospholipids of mitochondria, endoplasmic reticulum, and plasma membrane was investigated by changing the ratio of 22:6(n-3) against 18:2(n-6) in a medium, in which Chinese hamster V79-R cells were grown. In those organelles, 18:2(n-6) and its elongation product (eicosadienoic acid) (20:2 (n-6)) were predominantly incorporated into phosphatidylcholine. However, 22:6(n-3) was incorporated more selectively into phosphatidylethanolamine than 18:2(n-6) and 20:2(n-6).

Identification and expression of the cDNA-encoding human mesotrypsin(ogen), an isoform of trypsin with inhibitor resistance

The cDNA encoding a novel isoform of human trypsinogen was identified. The isoelectric points of the proenzyme and active forms calculated from the deduced amino acid sequence are consistent with those of mesotrypsin(ogen), known to be an inhibitor-resistant trypsin isoform. The cDNA attached with a bacterial signal peptide sequence was expressed in Escherichia coli. The recombinant proenzyme purified from periplasm showed enterokinase-dependent activation similar to a major isoform of human trypsinogen. The enzyme was far less inhibited by trypsin inhibitors such as soybean trypsin inhibitor, aprotinin, or pancreatic secretory trypsin inhibitor than the control trypsin. A gel filtration assay showed that the enzyme and aprotinin did not form a stable complex. It is noteworthy that the amino acid at position 198, which is in close vicinity to the active Ser, is Arg while those of other major trypsins are all Gly. It is concluded that the cloned cDNA encodes human mesotrypsinogen, a unique isoform of trypsinogen with inhibitor resistance.

Hepatocyte growth factor activator inhibitor, a novel Kunitz-type serine protease inhibitor

Hepatocyte growth factor (HGF) activator is a serine protease that is produced and secreted by the liver and circulates in the blood as an inactive zymogen. In response to tissue injury, the HGF activator zymogen is converted to the active form by limited proteolysis. The activated HGF activator converts an inactive single chain precursor of HGF to a biologically active heterodimer in injured tissue. The activated HGF may be involved in the regeneration of the injured tissue. In this study, we purified an inhibitor of HGF activator from the conditioned medium of a human MKN45 stomach carcinoma cell line and molecularly cloned its cDNA. The sequence of the cDNA revealed that the inhibitor has two well defined Kunitz domains, suggesting that the inhibitor is a member of the Kunitz family of serine protease inhibitors. The sequence also showed that the primary translation product of the inhibitor has a hydrophobic sequence at the COOH-terminal region. Inhibitory activity toward HGF activator was detected in the membrane fraction as well as in the conditioned medium of MKN45 cells. These results suggest that the inhibitor may be produced as a membrane-associated form and secreted by the producing cells as a proteolytically truncated form.

Extensive facial strawberry mark associated with cerebellar hypoplasia and vascular abnormalities

Strawberry mark is considered a benign hemangioma with a tendency toward spontaneous regression and a benign prognosis. Recently, some papers have reported complications of large facial strawberry marks. We report a infant girl with an extensive strawberry mark on the left side of the face associated with ipsilateral cerebellar hypoplasia and Dandy-Walker malformation. Abnormal branching of the aortic arch was also found.

Increase in lysophosphatidylethanolamine in the cell membrane upon the regulated exocytosis of pancreatic acinar AR42J cells

A specific cytosolic phospholipase A2 inhibitor, arachidonyl trifluoromethyl ketone (AACOCF3), was found to inhibit the regulated exocytosis of pancreatic acinar AR42J cells. When AR42J cells were stimulated with cholecystokinin octapeptide (CCK-8), the regulated exocytosis monitored by amylase release was rapidly activated and increased by 2.5-fold during one hour. After AR42J cells were treated with AACOCF3, amylase release by CCK-8 remained at the basal level. Thus, changes in the composition of membrane phospholipids before and after stimulation were investigated. Within 1 min after CCK-8 stimulation, lysophosphatidylethanolamine (lysoPE) in the cellular membranes of AR42J was increased while lysophosphatidylcholine stayed unchanged. In the presence of AACOCF3, lysoPE was not increased by CCK-8. Those results indicate that the increment of lysoPE is linked to the regulated exocytosis.

Three cases of Pasteurella multocida skin infection from pet cats

We encountered three cases of Pasteurella multocida skin infection from pet cats. P. multocida wound infections are characterized by acute onset of erythema, pain, and swelling. This infection has rarely been reported in dermatology journals from Japan.

Mechanisms of T-type calcium channel blockade by zonisamide

We investigated the effects of zonisamide, a new antiepileptic drug, on voltage-dependent T-type calcium current (ICa) in cultured neuroblastoma cells of human origin (NB-I). Zonisamide reduced T-type ICa in a concentration-dependent manner without evoking any change in its inactivation kinetics or voltage dependence of action. The mean percent reduction was 38.3 +/- 5.8% at 50 microM. Further, zonisamide shifted the inactivation curve approximately 20 mV negative compared to the control. These resting blocking actions suggest that zonisamide shifts the channel population toward the inactivation state, allowing fewer channels to open during membrane depolarization. The blockade of T-type calcium channels by zonisamide could suppress an important component of inward current that underlies epileptiform cellular bursting, thereby inhibiting the spread of seizure activity.

Inhibition assay for the binding of biotinylated von Willebrand factor to platelet-bound microtiter wells in the presence of ristocetin or botrocetin

We developed a solid-phase inhibition assay for the binding of biotinylated von Willebrand factor (vWF) to platelet glycoprotein (GP)Ib based on an enzyme-linked immunosorbent assay (ELISA) with platelet-bound microtiter wells. Washed platelets were immobilized onto the microplates via the anti-GPIIb/IIIa monoclonal antibody (mAb) VNR-5. In the presence of an antibiotic ristocetin (1 mg/ml, final) or the snake venom botrocetin (2 micrograms/ml, final), biotinylated vWF bound to the affixed platelets with half-maximal binding occurring at a vWF concentration of approximately 2 micrograms/ml. Several specific inhibitors of the binding of vWF to GPIb abolished the interaction of biotinylated vWF with GPIb in a dose-dependent fashion, with comparable protein concentrations to those seen in the liquid-phase inhibition assay using 125I-vWF. These inhibitors included mAb against vWF (NMC-4), mAb against GPIb (AP-1), and two vWF fragments containing vWF's putative GPIb-binding domain, namely a 39/34-kDa dispase-digested vWF fragment and a recombinant vWF fragment. Thus, this new assay is a convenient alternative to the conventional inhibition assay using 125I-vWF.

Calcium and SLY genes suppress the temperature-sensitive secretion defect of Saccharomyces cerevisiae uso1 mutant

Saccharomyces cerevisiae uso1-1 mutant stops the transport of secretory proteins from the endoplasmic reticulum to the Golgi apparatus at 37 degrees C. We found that this temperature-sensitive defect was suppressed either by increasing the concentration of calcium ion in the medium or by introducing in the cell the SLY genes which suppress the defect of Ypt1 protein, a small GTP-binding protein. The common phenotype and suppression of the mutants suggest that Uso1 and Ypt1 proteins function in the same process of protein transport, i.e., targeting or fusion of the transport vesicles to the Golgi membrane.

Modification tolerability of soybean proglycinin

Proglycinins containing multiple modifications, that is, with two kinds of single modifications, designed previously to improve food functions, were assessed for ability to form proper conformations. This was done to discover the modification tolerability of proglycinin. Based on our results, three new criteria are proposed for judging formation of proper conformations. Our results suggest that proglycinin molecules tolerate different combinations of single modifications without misfolding.

A possible role of ER-60 protease in the degradation of misfolded proteins in the endoplasmic reticulum

Wild-type human lysozyme (hLZM) is secreted when expressed in mouse L cells, whereas misfolded mutant hLZMs are retained and eventually degraded in a pre-Golgi compartment (Omura, F., Otsu, M., Yoshimori, T., Tashiro, Y., and Kikuchi, M. (1992) Eur. J. Biochem. 210, 591-599). These misfolded mutant hLZMs are associated with protein disulfide isomerase (Otsu, M., Omura, F., Yoshimori, T., and Kikuchi, M. (1994) J. Biol. Chem. 269, 6874-6877). From the observation that this degradation is sensitive to cysteine protease inhibitors, such as N-acetyl-leucyl-leucyl-norleucinal and N-acetyl-leucyl-leucyl-methioninal, but not to the serine protease inhibitors, 1-chloro-3-tosylamido-7-amino-2-heptanone and (p-amidinophenyl)methanesulfonyl fluoride, it was suggested that some cysteine proteases are likely responsible for the degradation of abnormal proteins in the endoplasmic reticulum (ER). ER-60 protease (ER-60), an ER resident protein with cysteine protease activity (Urade, R., Nasu, M., Moriyama, T., Wada, K., and Kito, M. (1992) J. Biol. Chem. 267, 15152-15159), was found to associate with misfolded hLZMs, but not with the wild-type protein, in mouse L cells. Furthermore, denatured hLZM is degraded by ER-60 in vitro, whereas native hLZM is not. These results suggest that ER-60 could be a component of the proteolytic machinery for the degradation of misfolded mutant hLZMs in the ER.

Selective incorporation of n-3 and n-6 unsaturated fatty acids into animal cell phospholipids

The selective incorporation of n-3 and n-6 unsaturated fatty acids into phospholipids was investigated by changing the ratio of n-3 unsaturated fatty acids against n-6 unsaturated fatty acids in the medium where Chinese hamster V79-R cells were grown. Unsaturated fatty acids with lower degrees of unsaturation were abundantly incorporated into phosphatidylcholine independently of n-3 and n-6. Unsaturated fatty acids with higher degrees of unsaturation were more predominantly incorporated into phosphatidylethanolamine. When the difference in the numbers of double bond between unsaturated fatty acids was more than two, the unsaturated fatty acids with a higher degree of unsaturation was more selectively incorporated into phosphatidylethanolamine than the unsaturated fatty acids with a lower degree of unsaturation. By the analysis of molecular species, n-3 and n-6 unsaturated fatty acids with higher degrees of unsaturation were incorporated competitively into phosphatidylethanolamine. Finally, docosahexaenoic acid was incorporated into diacyl phosphatidylethanolamine more selectively than the other unsaturated fatty acids.