Rotator cuff surgery in patients older than 75 years with large and massive tears

BACKGROUND

The purpose of this study was to evaluate whether rotator cuff repair improves subjective and functional outcomes in patients aged ≥75 years.

METHODS

From May 2005 to March 2013, 121 elderly patients who underwent rotator cuff repair for large and massive rotator cuff tears were evaluated retrospectively. Patients with an American Society of Anesthesiologists physical status classification system grade ≥4 were excluded. The patients were evaluated using visual analog scales, subjective satisfaction surveys, American Shoulder and Elbow Surgeons scores, and Constant scores. The Katz index of activity of daily living (ADL) and functional independence measure motor score were used to evaluate ADLs. Postoperative magnetic resonance imaging (MRI) was performed to investigate the structural integrity of repaired cuffs.

RESULTS

In total, 64 patients were enrolled in the study; 80% were satisfied with their results. Visual analog scale scores improved from 6.4 to 2.3, American Shoulder and Elbow Surgeons scores from 42 to 84, and Constant scores from 42 to 76. Katz ADL scores improved from 3.4 to 5.0. Functional independence measure motor score improved from 22 to 51. Of the 64 patients, 46 underwent MRI 1 year postoperatively. Follow-up MRI revealed retears in 26% of patients. All patients with retears had improved subjective outcomes and functional scores. No patients died or experienced complications requiring intensive care or extended hospitalization.

CONCLUSIONS

Surgical treatment for large to massive rotator cuff tears in elderly patients with American Society of Anesthesiologists grade <4 provides good functional outcomes without morbidity, even in those with retears.

Redisplacement of Distal Radius Fracture after Initial Closed Reduction: Analysis of Prognostic Factors

BACKGROUND

To evaluate risk factors of redisplacement and remind surgeons of key factors regarding conservative treatment of distal radius fracture.

METHODS

A total of 132 patients who received conservative treatment for distal radius fractures between March 2008 and February 2011 were included in this study. Radial inclination, radial length, volar tilting angle, ulnar variance, fragment translation, and presence of dorsal metaphyseal comminution were measured on the X-rays taken immediately after reduction, one week after injury during the first follow-up outpatient clinic visit, and after the gain of radiological union. Secondary displacement was defined as a loss of reduction during the follow-up period, and was divided into 'early' and 'late' categories. We analyzed the influence of initial displacement radiologic variables, dorsal cortex comminution, and patient age on the development of secondary displacement.

RESULTS

Development of secondary displacement was significantly associated only with initial displacement radiologic variables (p < 0.001), development of the late secondary displacement was significantly associated with age (p = 0.005), and initial displacement radiologic variables were associated significantly with a serial increase in ulnar variance (p = 0.003).

CONCLUSIONS

Greater displacement on the initial radiographs indicates a higher possibility of development for secondary displacement, and older patients had a higher probability of late secondary displacement development. Furthermore, dorsal comminutions did not affect secondary displacement directly.

Redisplacement of Distal Radius Fracture after Initial Closed Reduction: Analysis of Prognostic Factors

BACKGROUND

To evaluate risk factors of redisplacement and remind surgeons of key factors regarding conservative treatment of distal radius fracture.

METHODS

A total of 132 patients who received conservative treatment for distal radius fractures between March 2008 and February 2011 were included in this study. Radial inclination, radial length, volar tilting angle, ulnar variance, fragment translation, and presence of dorsal metaphyseal comminution were measured on the X-rays taken immediately after reduction, one week after injury during the first follow-up outpatient clinic visit, and after the gain of radiological union. Secondary displacement was defined as a loss of reduction during the follow-up period, and was divided into 'early' and 'late' categories. We analyzed the influence of initial displacement radiologic variables, dorsal cortex comminution, and patient age on the development of secondary displacement.

RESULTS

Development of secondary displacement was significantly associated only with initial displacement radiologic variables (p < 0.001), development of the late secondary displacement was significantly associated with age (p = 0.005), and initial displacement radiologic variables were associated significantly with a serial increase in ulnar variance (p = 0.003).

CONCLUSIONS

Greater displacement on the initial radiographs indicates a higher possibility of development for secondary displacement, and older patients had a higher probability of late secondary displacement development. Furthermore, dorsal comminutions did not affect secondary displacement directly.

Inguinal approach for the management of unilateral non-palpable testis: is diagnostic laparoscopy necessary?

OBJECTIVE

During the last decade laparoscopy has increasingly been advocated as the primary investigative procedure for the management of the non-palpable testis. We reviewed the medical records in a consecutive series of boys with non-palpable testis to examine the contribution of the initial inguinal approach in the management of unilateral non-palpable testis.

MATERIALS AND METHODS

Among the 183 consecutive patients with cryptorchidism from 2003 to 2012, there were 21 patients with unilateral and three with bilateral non-palpable testes. All unilateral patients then underwent inguinal and scrotal exploration through an inguinal incision. For those patients with an intra-abdominal peeping testis, the gonad was placed into the scrotum after meticulous cranial mobilization of the spermatic cord.

RESULTS

Patient age ranged from 11 months to 144 months (mean age: 23 months). Among the 21 unilateral cases, testicular absence or atrophy was confirmed in seven patients with a scrotal nubbin in six, and blind-ending vas and vessels at the external inguinal ring in one patient. Among the remaining 14 patients with sizeable testes, 12 testes were intra-abdominal peeping testes and two testicles were seen within the distal inguinal canal, which may be missed on physical examination owing to patient obesity. The intra-abdominal peeping testicle had the opened processus vaginalis entering the internal ring in which testicle was found. These were fixed into the scrotum successfully by cranial mobilization of spermatic vessel sometimes cutting the internal oblique muscle and by Prentiss and Fowler-Stephen's maneuver. Diagnostic laparoscopy was done on three patients with bilateral cases.

CONCLUSIONS

Given the result that most of nubbins are within the scrotum and testes with intra-abdominal peeping testes are fixed down safely into the scrotum, the inguinal approach may suffice for the management of unilateral non-palpable testis. Laparoscopy should be reserved for patients with bilateral non-palpable undescended testes.

Antitumor activity of Ad-IU2, a prostate-specific replication-competent adenovirus encoding the apoptosis inducer, TRAIL

In this study, we investigated the preclinical utility and antitumor efficacy of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) delivered by Ad-IU2, a prostate-specific replication-competent adenovirus (PSRCA), against androgen-independent prostate cancer. Through transcriptional control of adenoviral early genes E1a, E1b and E4, as well as TRAIL by two bidirectional prostate-specific enhancing sequences (PSES), expression of TRAIL as well adenoviral replication was limited to prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA)-positive cells. Ad-IU2 induced 5-fold greater apoptosis selectively in PSA/PSMA-positive CWR22rv and C4-2 cells than an oncolytic adenoviral control. Furthermore, prolonged infection with Ad-IU2 reversed TRAIL resistance in LNCaP cells. Ad-IU2 exhibited superior killing efficiency in PSA/PSMA-positive prostate cancer cells at doses 5- to 8-fold lower than required by a PSRCA to produce a similar effect. This cytotoxic effect was not observed in non-prostatic cells, however. As an enhancement of its therapeutic efficacy, Ad-IU2 exerted a TRAIL-mediated bystander effect through direct cell-to-cell contact and soluble factors such as apoptotic bodies. In vivo, Ad-IU2 markedly suppressed the growth of subcutaneous androgen-independent CWR22rv xenografts compared to a PSRCA at six weeks post-treatment (3.1- vs. 17.1-fold growth of tumor). This study demonstrates the potential clinical utility of a PSRCA armed with an apoptosis-inducing ligand.

VDUP1 potentiates Ras-mediated angiogenesis via ROS production in endothelial cells

Vitamin D3 up-regulated protein 1 (VDUP1) is a tumor suppressor of which expression is reduced in a variety of cancer cells, and enforced expression inhibits the tumor cell proliferation. It inhibits the activity of thioredoxin, thus contributing cellular ROS generation. Since ROS is a critical factor for angiogenesis, we investigated the role of VDUP1 in angiogenesis and endothelial proliferation. The expression of VDUP1 was upregulated by overexpression of an oncogene, Ras. Enforced expression of VDUP1 increases ROS production and proliferation of Ras-overexpressing endothelial cells. Overexpression of VDUP1 increases the resistance to the anchorage-dependent cell death and tube formation of the Ras-overexpressing endothelial cell. In addition, the removal of ROS by ROS scavenger attenuates the effect of VDUP1 on tube formation. These results suggest that VDUP1 is involved in Ras-mediated angiogenesis via ROS generation in endothelial cells.

A comparison of oral health related quality of life between complete and partial removable denture-wearing older adults in Korea

The purpose of this study was to compare the oral health related quality of life (OHRQoL) between older Korean adults with complete and partial removable dentures using oral health impact profile (OHIP). A pool of 4250 Korean older adults was identified by random stratification by area from the sample cohort of Korean National Survey of Oral Health in the year of 2000. Out of the potential pool, 445 subjects with removable partial dentures (RPDs) or complete dentures (CDs) agreed to be interviewed by telephone. Each question in the survey was about how frequently each event was experienced during the past 12 months. To analyse the association between OHIP scores and removable denture status, bivariable analysis and multiple linear regression analysis were used. RPD users showed higher scores on eight items than CD users. They were 'breath stale', 'food catching', 'sensitive teeth', 'toothache', 'tense', 'unable to brush teeth', 'less tolerant to family members' and 'irritable with others'. RPD users might be associated with higher scores of functional limitation, physical pain and psychological discomfort than CD users. RPD users had slight tendency to be associated with higher OHIP-49 score than CD users, but it was not statistically significant. The findings of the present study confirm that there is no general OHRQoL difference between RPD and CD users. But in the items and subscales of OHIP, RPD users might experience more impaired OHRQoL than CD users.

RPA governs endonuclease switching during processing of Okazaki fragments in eukaryotes

Extensive work on the maturation of lagging strands during the replication of simian virus 40 DNA suggests that the initiator RNA primers of Okazaki fragments are removed by the combined action of two nucleases, RNase HI and Fen1, before the Okazaki fragments join. Despite the well established in vitro roles of these two enzymes, genetic analyses in yeast revealed that null mutants of RNase HI and/or Fen1 are not lethal, suggesting that an additional enzymatic activity may be required for the removal of RNA. One such enzyme is the Saccharomyces cerevisiae Dna2 helicase/endonuclease, which is essential for cell viability and is well suited to removing RNA primers of Okazaki fragments. In addition, Dna2 interacts genetically and physically with several proteins involved in the elongation or maturation of Okazaki fragments. Here we show that the endonucleases Dna2 and Fen1 act sequentially to facilitate the complete removal of the primer RNA. The sequential action of these enzymes is governed by a single-stranded DNA-binding protein, replication protein-A (RPA). Our results demonstrate that the processing of Okazaki fragments in eukaryotes differs significantly from, and is more complicated than, that occurring in prokaryotes. We propose a novel biochemical mechanism for the maturation of eukaryotic Okazaki fragments.

Tripartite structure of Saccharomyces cerevisiae Dna2 helicase/endonuclease

In order to gain insights into the structural basis of the multifunctional Dna2 enzyme involved in Okazaki fragment processing, we performed biochemical, biophysical and genetic studies to dissect the domain structure of Dna2. Proteolytic digestion of Dna2 using subtilisin produced a 127 kDa polypeptide that lacked the 45 kDa N-terminal region of Dna2. Further digestion generated two subtilisin-resistant core fragments of approximately equal size, 58 and 60 kDa. Surprisingly, digestion resulted in a significant (3- to 8-fold) increase in both ATPase and endonuclease activities compared to the intact enzyme. However, cells with a mutant DNA2 allele lacking the corresponding N-terminal region were severely impaired in growth, being unable to grow at 37 degrees C, indicating that the N-terminal region contains a domain critical for a cellular function(s) of Dna2. Analyses of the hydrodynamic properties of and in vivo complex formation by wild-type and/or mutant Dna2 lacking the N-terminal 45 kDa domain revealed that Dna2 is active as the monomer and thus the defect in the mutant Dna2 protein is not due to its inability to multimerize. In addition, we found that the N-terminal 45 kDa domain interacts physically with a central region located between the two catalytic domains. Our results suggest that the N-terminal 45 kDa domain of Dna2 plays a critical role in regulation of the enzymatic activities of Dna2 by serving as a site for intra- and intermolecular interactions essential for optimal function of Dna2 in Okazaki fragment processing. The possible mode of regulation of Dna2 is discussed based upon our recent finding that replication protein A interacts functionally and physically with Dna2 during Okazaki fragment processing.

Enhancement of secretion and extracellular stability of staphylokinase in Bacillus subtilis by wprA gene disruption

Staphylokinase (SAK), a polypeptide secreted by Staphylococcus aureus, is a plasminogen activator with a therapeutic potential in thrombosis diseases. A Bacillus subtilis strain which is multiply deficient in exoproteases was transformed by an expression plasmid carrying a promoter and a signal sequence of subtilisin fused in frame with the sak open reading frame. However, the amount of SAK secretion was marginal (45 mg/liter). In contrast, disruption of the wprA gene, which encodes a subtilisin-type protease, strongly promoted the production of SAK in the stationary phase (181 mg/liter). In addition, the extracellular stability of mature SAK was dramatically enhanced. These data indicate a significant role of the wprA gene product in degrading foreign proteins, both during secretion and in the extracellular milieu.

Antifungal activity of magnolol and honokiol

Two neolignan compounds, magnolol (5,5'-diallyl-2,2'-dihydroxybiphenyl, 1) and honokiol (5,5'-diallyl-2,4'-dihydroxybiphenyl, 2), were isolated from the stem bark of Magnolia obovata and evaluated for antifungal activity against various human pathogenic fungi. Compound 1 and 2 showed significant inhibitory activities against Trichophyton mentagrophytes, Microsporium gypseum, Epidermophyton floccosum, Aspergillus niger, Cryptococcus neoformans, and Candida albicans with minimum inhibitory concentrations (MIC) in a range of 25-100 microg/ml. Therefore, compound 1 and 2 could be used as lead compounds for the development of novel antifungal agents.

Screening of Korean plants against human immunodeficiency virus type 1 protease

With the aim of finding novel anti-human immunodeficiency virus agents from natural products, 93 MeOH extracts of Korean plants were screened for their inhibitory activities against HIV-1 protease. The most potent inhibition was shown by the root of Rodiola rosea with 70.4% inhibition at a concentration of 100 microg/mL.

Cholesterol-lowering activity of naringenin via inhibition of 3-hydroxy-3-methylglutaryl coenzyme A reductase and acyl coenzyme A:cholesterol acyltransferase in rats

The effects of dietary supplementation of a citrus bioflavonoid, naringenin, on the cholesterol metabolism were studied. For 42 days male rats were fed a 1% (wt/wt) high-cholesterol diet with or without a naringenin supplementation (0.1%, wt/wt) to study its effect on plasma lipid levels, hepatic lipid contents, activities of hepatic acyl coenzyme A:cholesterol O-acyltransferase (ACAT) and 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, and the excretion of fecal neutral sterols. Naringenin did not significantly alter the concentration of plasma triglycerides, but lowered the plasma cholesterol (3.80 vs. 3.12 mmol/l) concentration and the hepatic cholesterol content (70.3 vs. 54.0 mg/g) significantly (p < 0.05) compared to those of the controls. HMG-CoA reductase (1,879.0 vs. 1,715.0 pmol/min/mg) and ACAT activities (806.0 vs. 563.0 pmol/min/mg) were significantly lower in the naringenin-supplemented group than in controls. Naringenin supplementation caused a marked decrease in the excretion of fecal neutral sterols (242.9 mg/day) compared to the controls (521.9 mg/day). These results show that naringenin lowers the plasma and hepatic cholesterol concentrations by suppressing HMG-CoA reductase and ACAT in rats fed a high-cholesterol diet.

Hypocholesterolemic effect of naringin associated with hepatic cholesterol regulating enzyme changes in rats

The effects of the citrus bioflavonoid naringin were tested by using it as a supplement in a high-cholesterol diet. Male rats were fed for 42 days with a 1% (wt/wt) high cholesterol diet either with or without naringin-supplementation (0.1%, wt/wt) to study the effect on plasma lipid levels, hepatic lipid contents, hepatic enzyme activity, and the excretion of fecal neutral sterols. Naringin did not significantly alter the levels of plasma triglycerides, however, the levels of plasma cholesterol (3.80 +/- 0.31 mmol/L vs. 2.61 +/- 0.30 mmol/L, mean +/- SE; p < 0.05) and hepatic cholesterol (70.3 +/- 4.3 mg/g vs. 54.3 +/- 3.8 mg/g, mean +/- SD; p < 0.05) were significantly lowered compared to those of the control. HMG-CoA reductase (2487.0 +/- 210.0 pmole/min/mg vs. 1879.0 +/- 236.0 pmole/min/mg, mean +/- SE; p < 0.05) and ACAT (806.0 +/- 105.0 pmole/min/mg vs. 643.0 +/- 80.0 pmole/min/mg, mean +/- SE; p < 0.05) activities were both substantially lower in the naringin-supplemented group than in the control. The naringin supplementation markedly decreased the excretion of fecal neutral sterols (204.7 +/- 28.5 mg/day) compared to the control (521.9 +/- 53.9 mg/day). The combination of the inhibited HMG-CoA reductase (-24.4%) and ACAT (-20.2%) activities as a result of naringin supplementation could account for the decrease of fecal neutral sterols.

Two new lignans from Lindera obtusiloba blume

Two new furanolignans (3, 5), together with three known lignans (1, 2, 4), were isolated from the stem of Lindera obtusiloba (Lauraceae). The structures of the compounds were determined as actifolin (1), pluviatilol (2), 5,6-dihydroxymatairesinol (3), (+)-syringaresinol (4), and (+)-9'-O-trans-feruloyl-5,5'-dimethoxylariciresinol (5) on the basis of physicochemical and spectroscopic evidences. Compounds 1, 2, 3, and 5 showed cytotoxicity against a small panel of human tumor cell lines with ED50 values of 3.40 to approximately 19.27 microg/ml.

Plasma and hepatic cholesterol and hepatic activities of 3-hydroxy-3-methyl-glutaryl-CoA reductase and acyl CoA: cholesterol transferase are lower in rats fed citrus peel extract or a mixture of citrus bioflavonoids

The cholesterol-lowering effects of tangerine peel extract and a mixture of two citrus flavonoids were tested. Male rats were fed a 1 g/100 g high-cholesterol diet for 42 d with supplements of either tangerine-peel extract or a mixture of naringin and hesperidin (0.5 g/100 g) to study the effects of plasma and hepatic lipids, hepatic enzyme activities, and the excretion of fecal neutral sterols. Both the tangerine-peel extract and mixture of two flavonoids significantly lowered the levels (mean +/- SE) of plasma (2.44 +/- 0. 59 and 2.42 +/- 0.31 mmol/L, vs. 3.80 +/- 0.28 mmol/L, P < 0.05), hepatic cholesterol (0.143 +/- 0.017 and 0.131 +/- 0.010 mmol/g vs. 0.181 +/- 0.003 mmol/g, P < 0.05), and hepatic triglycerides (0.069 +/- 0.007 and 0.075 +/- 0.006 mmol/g vs. 0.095 +/- 0.002 mmol/g, P < 0.05) compared to those of the control. The 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase (1565.0 +/- 106. 0 pmol. min-1. mg protein-1 and 1783.0 +/- 282 pmol. min-1. mg protein-1 vs. 2487.0 +/- 210.0 pmol. min-1. mg protein-1, P < 0.05) and acyl CoA: cholesterol O-acyltransferase (ACAT) activities (548.0 +/- 65.0 and 615.0 +/- 80.0 pmol. min-1. mg protein-1 vs. 806.0 +/- 105.0 pmol. min-1. mg protein-1, P < 0.05) were significantly lower in the experimental groups than in the control. These supplements also substantially reduced the excretion of fecal neutral sterols compared to the control (211.1 +/- 26.7 and 208.2 +/- 31.6 mg/d vs. 521.9 +/- 53.9 mg/d). The inhibition of HMG-CoA reductase and ACAT activities resulting from the supplementation of either tangerine-peel extract or a combination of its bioflavonoids could account for the decrease in fecal neutral sterol that appears to compensate for the decreased cholesterol biosynthesis in the liver.

Chitin synthase II inhibitory activity of ursolic acid, isolated from Crataegus pinnatifida

Two triterpenoid compounds, ursolic acid and uvaol, were isolated from Crataegus pinnatifida Bunge leaves. Ursolic acid inhibits chitin synthase II from S. cerevisiae with an IC50 value of 0.84 microgram/ml and the inhibition appears to be selective for chitin synthase II, whereas uvaol has no inhibitory activity up to 280 micrograms/ml. Oleanolic acid, alpha-hederin hydrate, and betulic acid inhibited the chitin synthase II activity under the same conditions with an IC50 of 5.6, 64.3, and 98.7 micrograms/ml, respectively.

Acyl-CoA:Cholesterol Acyltransferase Inhibitory Activity of Lignans Isolated from Schizandra, Machilus and Magnolia Species

Fifteen lignans were isolated from the fruits of SCHIZANDRA CHINENSIS, the leaves of MACHILUS THUNBERGII, and the flower buds of MAGNOLIA DENUDATA. They were identified as gomisins, schizandrin, wuweizisu, schizantherin, licarins, and machilin, which inhibited rat liver ACAT with IC (50) values of 25-200 microM. Comisin N is the most potent inhibitor with IC (50) value of 25 microM in these lignans.

Dimeric beta-cyclodextrin-based supramolecular ligands and their copper(II) complexes as metalloenzyme models

New supramolecular ligands possessing linear 13- and 15-membered pyridine diamidetriamine chelators between the primary sides of two beta-cyclodextrin cavities were synthesized, and characterized by MALDI-MS, NMR, IR and UV-Visible spectroscopy. Fluorescence and pH-metric titration were carried out in order to ascertain their behavior as bifunctional hosts for fluorescent guests and Cu(II) ion. The pKa value for the Cu(II) promoted deprotonation of amide ligands was determined to be 6.2 from pH-absorbance profile. Above pH 8.0, two deprotonated amides and three amino groups chelated Cu(II) ion, and yielded penta-coordinated Cu(II) complexes. The Cu(II) complexes catalyzed the hydrolysis of p-nitrophenyl acetate, adamantate and amino acids. Especially, the complex containing 13-membered chelator is an artificial metalloesterase with catalytic rate constant kcat = 3.8 x 10(-3) min-1 and Michaelis constant K(m) = 3.5 x 10(-4) M for the hydrolysis of p-nitrophenyl adamantate via metal-hydroxide mechanism.

Streptokinase secretion by Serratia marcescens signaled by the C-terminal 41 amino acid segment of metalloprotease

In order to investigate the secretion signal of Serratia marcescens metalloprotease (SMP) and examine the ability of the secretion signal to secrete foreign proteins, hybrid genes encoding the passenger-SMP C-terminal segments were constructed. As a passenger protein, streptokinase (SK) deprived of its signal peptide was used. Three kinds of SMP C-terminal segments containing 41, 80, or 220 amino acid residues were fused to the C-terminus of SK as secretion signals. The SK-SMP chimeric proteins containing 41 or 220 amino acid segments of the SMP C-terminus were secreted into the culture medium by the SMP transporter of S. marcescens. This result suggests that cytoplasmic SK is secreted into the external medium by the C-terminal segments of SMP and also shows that the smallest, 41 amino acid segment of the SMP C-terminus functions as a secretion signal of foreign proteins as well as SMP.

The Leu-3 residue of Serratia marcescens metalloprotease inhibitor is important in inhibitory activity and binding with Serratia marcescens metalloprotease

Serratia marcescens metalloprotease inhibitor (SmaPI) is a proteinase inhibitor toward Serratia marcescens metalloprotease (SMP). In sequential deletion analysis of the N-terminal region of the SmaPI, SmaPIs starting at Ser-2 and Leu-3 residues, respectively, had nearly a full inhibitory activity toward SMP. However, SmaPI starting at Ala-4 residue showed severely decreased inhibitory activity. Furthermore, kinetic analysis demonstrated that SmaPI starting at the Ala-4 residue had an inhibition constant for SMP approximately fourfold higher than that of wild-type SmaPI. The interactions of Leu-3 with SMP contribute 0.73 kcal mol-1 to the overall stability of the SMP-SmaPI complex (8.44 kcal mol-1). To elucidate the detailed role of the Leu-3 residue in inhibitory activity of SmaPI, several site-directed mutations were introduced. The inhibitory activities of Leu-3 mutants in which the Leu-3 has been converted to Ala, Asp, Gly, Ile, Lys, Phe, or Pro were correlated with the hydrophobicities of substituted amino acids. About 0.3 kcal mol-1 is attributable to the side chain of the Leu-3 residue in the binding with SMP. From these results, it is suggested that (i) in contrast with the Erwinia chrysanthemi inhibitor, Gly-1 and Ser-2 of SmaPI are not critical and (ii) the hydrophobicity of Leu-3 may be important in its inhibitory activity and binding with SMP.

Lathyrus saponin, a new trisaccharide glycoside from Lathyrus japonicus

A new triterpenoid saponin, named Lathyrus saponin (3), was isolated from the whole plant of Lathyrus japonicus Willd. together with two known saponins, azukisaponins II (1) and V (2). as their methyl esters. The structure of 3 was determined to be soyasapogenol B 3-0-beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl(1-->2)-beta-D-glu curonopyranoside on the basis of physicochemical and spectroscopic methods.

Effect on product specificity of cyclodextrin glycosyltransferase by site-directed mutagenesis

Cyclodextrin glycosyltransferase (CGTase; EC 2.4.1.19) catalyzes the degradation of starch into cyclodextrins through an intramolecular transglycosylation reaction. Tyr-89, Asn-94, and Tyr-100 are located near the putative active center. To analyze their roles in product specificity, Tyr-89, Asn-94, and Tyr-100 of CGTase from alkalophilic Bacillus sp. I-5 were replaced with different amino acids. Among the mutants, the N94S mutant protein produced about two times more alpha-cyclodextrin than the wild-type at all incubation times. The Y89F and Y100F mutant proteins were changed to more beta-specific enzymes. From these results it is suggested that the changing of the residues located at the near active site can change the product specificity of CGTase.

Pharmacological effects of methanolic extract from the root of Scutellaria baicalensis and its flavonoids on human gingival fibroblast

The methanolic extract from the root of Scutellaria baicalensis Georgi and its flavonoids, wogonin, baicalein, and baicalin were evaluated for anti-inflammatory action and the activatory effect on gingival fibroblasts. In LPS-induced production of IL-1 beta, three flavonoids at 1 microgram/ml expressed a significant (> 50%) inhibitory effect, similar to that of prednisolone. Moreover, the flavonoids inhibited IL-1 beta-induced synthesis of PGE2 and LTB4 considerably, although the effect of wogonin on LTB4 synthesis was marginal. In addition, three flavonoids exerted a moderate inhibition (33-36%) of collagenolytic activity, comparable to 40% inhibition by tetracycline. Meanwhile, the cellular activity of fibroblasts was augmented remarkably (40%) by baicalein (2) and slightly by baicalin (3) or wogonin (1). Consistent with the cellular activation, flavonoids enhanced the synthesis of both collagen and total protein in fibroblasts, in contrast to growth factors which increased only the synthesis of total protein. Although the effects of the methanolic extract resembled those of the flavonoids, the extract expressed a preferential effect on the synthesis of collagen and total protein.

Improvement of thermal stability of subtilisin J by changing the primary autolysis site

The thermostability of subtilisin J, an extracellular serine protease secreted from Bacillus stearothermophilus, has been improved by changing the primary autolysis site of the Asp-49 mutant protein. Previously we have shown that the Asp-49 mutant protein has proteolytic activity, but so unstable that it was primarily autolyzed in Tyr-58-Gln-59 peptide bond during cultivation (Jang et al. Biochim. Biophys. Acta. 1162, 233-235 1993). In the present study, to mitigate the autolytic degradation and increase the thermostability, we deleted the Tyr-58 residue using the Asp-49 mutant as a template. This mutant (Asp-49/delta Tyr-58 mutant) protein showed an improved resistance to heat treatment without changing the catalytic efficiency of the enzyme. These results show that change of primary autolysis site can stabilize the subtilisin.

Effect of the weak Ca2+-binding site of subtilisin J by site-directed mutagenesis on heat stability

The functional role of the negatively charged amino acid residue in subtilisin J from Bacillus stearothermophilus has been investigated by site-directed mutagenesis. Glu-195 located at the weak Ca2+-binding site was replaced with Gln to examine the role of Glu-195 in the heat stability of subtilisin J. Mutant enzyme was expressed in Bacillus subtilis and was purified from the culture supernatant. When the mutant enzyme was expressed at 37 degrees C in the presence of 2mM calcium chloride, the pattern of enzyme production was quite different from that of wild-type. The purified Gln-195 mutant enzyme was analyzed with respect to optimal temperature, optimal pH, and heat stability. The mutation was found to decrease the heat stability but not catalytic efficiency (kcat/Km) and optimal pH. These results demonstrate the important role of the negatively charged side chains at the weak Ca(2+)-binding site in the heat stability of subtilisin.

Synthesis and antibacterial activities of 4-hydroxy-o-phenylphenol and 3,6-diallyl-4-hydroxy-o-phenylphenol against a cariogenic bacterium Streptococcus mutans OMZ 176

For the purpose of survey of the antibacterial activity against a cariogenic bacterium Streptococcus mutans OMZ 176 with the introduction of hydroxyl and allyl groups to o-phenylphenol (Fig. 2, 1), 4-hydroxy-o-phenylphenol (2), and 3,6-diallyl-4-hydroxy-o-phenylphenol (4) were synthesized, successively. The synthesized compounds, 2 and 4 showed more potent antibacterial activity than the starting material, 1. The hydroxyl group was supposed to the essential element for the antibacterial activity and the introduction of allyl group to phenolic ring to be another element to increase the activity.