Cementless total hip arthroplasty in young Chinese patients: a comparison of 2 different prostheses

Sixty-one primary cementless total hip arthroplasties were performed in 45 Chinese patients <40 years old. There were 27 Anatomic Medullary Locking (AML, Depuy, Warsaw, IN) prostheses and 34 Porous Coated Anatomic (PCA, Howmedica, Rutherford, NJ) prostheses. The average follow-up was 7.6 years (range, 3-11 years). Ten hips (16%) were reoperated; the reason was polyethylene wear with or without osteolysis in 7 hips. Osteolytic lesion was present in 34 hips (56%). The cumulative successful rate at 10 years was 67% using reoperation for any reason as the endpoint. The cumulative successful rate was 98%, however, if revision for aseptic loosening was used as the endpoint. The 2 prostheses did not show significant differences in most parameters except that the PCA hips had significantly more acetabular loosening (P =.02) and periprosthetic osteolysis (P =.01).

Application of life-cycle assessment to type III environmental declarations

The objective of this research is to develop a desirable type III environmental declaration format for the industrial consumer. A total of five different scenarios were chosen for the presentation of life-cycle assessment results in a format that meets the requirements of a type III environmental declaration. Life-cycle assessment of an electronic component was performed for this purpose. Environmentally significant impact categories and input/output items of a product system derived from the life-cycle assessment are presented in this format. Presenting these information concisely in a standardized format would accelerate the communication of environmental aspects of materials and components in a product supply chain. Thus the type III environmental declaration can be a useful instrument for the manufacturing of an ecoproduct.

TGF-beta1 is the factor secreted by proliferative chondrocytes to inhibit neo-angiogenesis

Growth plate is an avascular tissue, which has been reported to be capable of retarding tumor spread. It is believed that angiogenic inhibitor(s) exist to inhibit the neo-vascularization of tumor, thus impeding the tumor growth. In this study, growth plate chondrocyte-derived TGFbeta1 was identified to be anti-angiogenic. It was found that growth plate chondrocytes (GPC) secreted TGFbeta1 mostly in latent form as demonstrated by gel filtration and immunoblotting. Enzyme-linked immunosorbent assay (ELISA) was followed to quantify TGFbeta1 in GPC conditioned medium (CM), in which 866 pg/ml of TGFbeta1 was found. Besides, the angiogenesis inhibitory effect of GPC CM was abolished by the addition of anti-TGFbeta1 antibody in the in vitro culture system and the in vivo chick chorioallantoic membrane (CAM) assay. This confirmed the anti-angiogenic properties of chondrocyte-derived TGFbeta1. TGFbeta1 was expressed predominantly in the proliferative zone of porcine growth plate. This explains the low incidence of tumor invasion across the entire growth plate. Also, this helps to explain the observation that tumor invasion across the physis increases with age as the proliferative zone gradually disappears. J. Cell. Biochem. Suppl. 36: 79-88, 2001.

Does computer-synthesized speech manifest personality? Experimental tests of recognition, similarity-attraction, and consistency-attraction

Would people exhibit similarity-attraction and consistency-attraction toward unambiguously computer-generated speech even when personality is clearly not relevant? In Experiment 1, participants (extrovert or introvert) heard a synthesized voice (extrovert or introvert) on a book-buying Web site. Participants accurately recognized personality cues in text to speech and showed similarity-attraction in their evaluation of the computer voice, the book reviews, and the reviewer. Experiment 2, in a Web auction context, added personality of the text to the previous design. The results replicated Experiment 1 and demonstrated consistency (voice and text personality)-attraction. To maximize liking and trust, designers should set parameters, for example, words per minute or frequency range, that create a personality that is consistent with the user and the content being presented.

The impact of risk on preference values: implications for evaluations of postmenopausal osteoporosis therapy

OBJECTIVE

The objective was to assess the impact of different levels of risk of disease on a woman's preferences for health states. Women were provided with health scenarios incorporating different levels of lifetime risks for breast cancer, hip fracture, and coronary heart disease (CHD). In this way, we were able to determine the incremental effect of changes in risks of each disease on preference values.

METHODS AND DATA

Preference values and utility scores were obtained for six health scenarios by both the feeling thermometer (FT) and standard gamble (SG) methods. Scenarios presented the different lifetime risks of CHD, breast cancer, and hip fracture associated with and not associated with long-term use of hormone replacement therapy (HRT) and raloxifene. Risks of breast cancer were based on perceived risks and population risks. The sample population consisted of 40 healthy female volunteers aged between 45 and 65 years randomly selected from the Ottawa-Carleton district.

RESULTS

Based on their perceived risk of breast cancer, the women had higher value scores for the raloxifene risk profile than for both HRT (p = .002) and no therapy (p = .003), with similar results for analyses based on population risks and from utility scores. Regression analysis showed that the risk of breast cancer (p < .001) was the only disease risk that was statistically significantly associated with women's preferences.

CONCLUSIONS

Women had significant preferences over the different risk profiles, primarily due to the incremental effect on changes in values for the risk of breast cancer. Therefore, studies evaluating therapies for osteoporosis should consider patient preferences for living with different risk profiles.

Dual functions of largest NURF subunit NURF301 in nucleosome sliding and transcription factor interactions

NURF is an ISWI complex of four proteins that uses the energy of ATP hydrolysis to catalyze nucleosome sliding. Three NURF components have been identified previously. We have cloned cDNA encoding the largest NURF subunit, revealing a 301 kDa polypeptide (NURF301) that shares structural motifs with ACF1. We have reconstituted full and partial NURF complexes from recombinant proteins and show that NURF301 and the ISWI ATPase are necessary and sufficient for accurate and efficient nucleosome sliding. An HMGA/HMGI(Y)-like domain of NURF301 that facilitates nucleosome sliding indicates the importance of DNA conformational changes in the sliding mechanism. NURF301 also shows interactions with sequence-specific transcription factors, providing a basis for targeted recruitment of the NURF complex to specific genes.

Comparison between anisometropic and strabismic amblyopia using functional magnetic resonance imaging

AIMS

To assess calcarine activation with functional magnetic resonance imaging (fMRI) in patients with anisometropic and strabismic amblyopia.

METHODS

14 amblyopes (eight anisometropic and six strabismic) were studied with fMRI using stimuli of checkerboards of various checker sizes and temporal frequencies. While T2* weighted MRI were obtained every 3 seconds for 6 minutes, patients viewed the stimuli monocularly with either the amblyopic or sound eye.

RESULTS

Amblyopic eyes showed reduced calcarine activation compared with contralateral sound eyes in fMRI in all subjects. The calcarine activation from amblyopic eyes in anisometropic amblyopes was more suppressed at higher spatial frequencies, while that from amblyopic eyes in strabismic amblyopes was more suppressed at lower spatial frequencies.

CONCLUSION

These results suggest that fMRI is a useful tool for the study of amblyopia in humans. The calcarine activation via amblyopic eyes because of anisometropia or strabismus has different temporospatial characteristics, which suggests differences in the neurophysiological mechanisms between two types of amblyopia.

Oxidative stress is more important than acid in the pathogenesis of reflux oesophagitis in rats

BACKGROUND

Although antisecretory medications such as histamine type II receptor antagonists or proton pump inhibitors have been used to treat reflux oesophagitis, a considerable number of patients do not achieve complete mucosal healing or suffer from either sustained symptoms or ensuing complications, suggesting other damaging factors or impaired mucosal resistance are also involved in the pathogenesis of reflux oesophagitis.

AIMS

The present study was designed to evaluate oxidative stress as the major pathogenic factor of reflux oesophagitis and to determine the usefulness of antioxidants in the treatment of reflux oesophagitis.

MATERIALS AND METHODS

Reflux oesophagitis was induced by insertion of a 3 mm calibre ring into the duodenum, 1 cm distal to the ligament of Treitz, in Sprague-Dawley rats.

RESULTS

DA-9601, a novel antioxidant substance, significantly attenuated the gross and histopathological scores of reflux oesophagitis compared with those treated with ranitidine alone or reflux oesophagitis controls in a dose dependent manner. Only scattered erosions were observed in the antioxidant pretreated group but acid suppression by ranitidine was not effective in decreasing the severity of reflux oesophagitis. Significantly increased amounts of malondialdehyde (MDA), increased nuclear factor kappaB (NFkappaB) activation, and depletion of reduced glutathione (GSH) were observed in experimentally induced reflux oesophagitis. DA-9601 pretreatment attenuated the decrement in mucosal GSH levels and decreased MDA formation significantly. DA-9601 treatment caused significant reductions in activation of NFkappaB transcription factor, especially the p50 subunit, in accordance with the significantly higher levels of inhibitory protein of NFkappaB expression.

CONCLUSION

Reflux oesophagitis caused considerable levels of oxidative stress in the oesophageal mucosa and antioxidant treatment should be considered as supplementary therapy in the prevention or treatment of reflux oesophagitis with acid suppression.

Differential gene expression in a murine model of cancer cachexia

Murine adenocarcinoma 16 (MAC16) tumors and cell lines induce cachexia in NMRI nude mice, whereas histologically similar MAC13 tumors do not. After confirming these findings in BALB/c nude mice, we demonstrated that this tissue wasting was not related to decreased food intake or increased total body oxidative metabolism. Previous studies have suggested that MAC16's cachexigenic properties may involve the production of tumor-specific factors. We therefore screened for genes having increased expression in the MAC16 compared with the MAC13 cell line by performing hybridization to a murine cDNA expression array, by generation and comparison of cDNA libraries from each cell line, and by PCR-based subtractive hybridization. Northern blot hybridization was performed to confirm differences in transcript expression. Transcripts encoding insulin-like growth factor binding protein-4, cathepsin B, ferritin light and heavy chain, endogenous long-terminal repeat sequences, and a viral envelope glycoprotein demonstrated increased expression in the MAC16 cell line. The roles of a number of these genes in known metabolic pathways identify them as potential participants in the induction of cachexia.

Molecular authentication of Panax ginseng species by RAPD analysis and PCR-RFLP

In order to develop convenient and reproducible methods for the identification of ginseng drugs at a DNA level, randomly amplified polymorphic DNA (RAPD) and PCR-restriction fragment length polymorphism (PCR-RFLP) analyses were applied within Panax species. To authenticate Panax ginseng among ginseng populations, RAPD analysis was carried out using a 20 mer-random primer. The similarity coefficients among the DNA of ginseng plants analyzed were low, ranging from 0.197 to 0.491. In addition, by using PCR-RFLP analysis, very different fingerprints were obtained within Korean ginseng plants. These results suggest that these methods are able to authenticate the concerned Panax species. Broader application of this approach to authenticate other morphologically similar medicinal materials is rationalized.

Parity problem with a cellular automaton solution

The parity of a bit string of length N is a global quantity that can be efficiently computed using a global counter in O(N) time. But is it possible to find the parity using cellular automata with a set of local rule tables without using any global counter? Here, we report a way to solve this problem using a number of r=1 binary, uniform, parallel, and deterministic cellular automata applied in succession for a total of O(N2) time.

Functional magnetic resonance imaging during pantomiming tool-use gestures

The purpose of this study was to identify the functional fields activated in relation to gestural movements. Using functional magnetic resonance imaging (fMRI), we mapped brain activity in ten right-handed, normal volunteers during activation and control tasks. The activation condition consisted of pantomiming tool-use gestures with either the left hand or right hand, whereas the control condition comprised repetitive, oppositional movements between thumb and index finger. Activated cortical regions were highly lateralized to the left hemisphere during pantomiming of tool use regardless of hand used. Praxis with either hand commonly activated the superior parietal lobule, supplementary motor area, premotor area of the left hemisphere, and cerebellar vermis. However, minimal activation occurred in the inferior parietal lobule, which has been known to be a critical area for praxis generation. Compared with left-hand praxis, right-hand praxis exhibited additional activation in the left putamen and posterior part of the left inferior temporal region. Our findings concur with neuropsychological observations that the left hemisphere in right-handers mediates programming and executing skilled movements and that, within the left hemisphere, praxis is predominantly subserved by the parietal lobe, supplementary motor area, and premotor area. However, unlike previous lesion studies, the results of our fMRI study suggested that the superior parietal lobule more likely than the inferior parietal lobule play an important role in gesture production.

In situ model for studying potassium currents in various growth plate chondrocyte subpopulations

A new in situ model of partially digested growth plate cartilage suitable for patch clamp study of membrane currents of chondrocytes from various differentiation stages was developed. Thin sections of growth plate were enzyme digested to expose intact membranes of chondrocytes previously covered by extracellular matrix. This treatment dramatically increased the success rate of tight-seal formation from virtually 0% up to 40%. Whole-cell patch clamp recording revealed a delayed outward rectifying current as the major macroscopic current in chondrocytes of all differentiation stages. This current was sensitive to tetraethylammonium chloride and reversed polarity at a membrane potential close to the equilibrium potential of K+. Chondrocytes at resting stage expressed a much smaller K+ current than the proliferative and hypertrophic chondrocytes. When the current amplitudes were normalized for the cell membrane area, proliferative cells expressed a significantly higher outward current density.

Identification of the self-interaction of rat TCTP/IgE-dependent histamine-releasing factor using yeast two-hybrid system

To further understand the biological function of translationally controlled tumor protein (TCTP), also known as IgE-dependent histamine-releasing factor (HRF), the yeast two-hybrid system was used to screen interacting molecules. We isolated cDNA clones coding for TCTP/HRF, suggesting that it may have a self-interacting property. Domain mapping of the interaction revealed that the C-terminal region of residue 126-172 is involved in self-interaction. The self-interacting property of TCTP/HRF was further supported by FPLC gel-filtration chromatography and coimmunoprecipitation analysis from transfected COS-7 cells. Our data suggests that TCTP/HRF may have a potential to self-interact through the C-terminal region, and the self-interaction property may be related to its biological function.

Binocularity and spatial frequency dependence of calcarine activation in two types of amblyopia

OBJECTIVE AND BACKGROUND

Strabismus and anisometropia early in life frequently causes monocular amblyopia. Activation of the visual cortex is compared between the two types of amblyopia to elucidate differences in the pathogenetic mechanism of the disease.

METHODS

Using an EPI gradient echo sequence in 1.5T MRI, calcarine activation by monocular viewing of checkerboard patterns with reversal was examined in terms of binocularity of the activation and dependence on the spatial frequency of the stimuli.

RESULTS

First, the proportion of voxels activated by both normal and amblyopic eye monocular stimulations is lower in the strabismic group than in the anisometropic group. Second, the activation by higher-spatial-frequency stimuli is reduced in the anisometropic group, but not in the strabismic group.

CONCLUSIONS

These findings from the human visual cortex are consistent with the view proposed based on animal research that the loss of binocular interaction and the undersampling of high-spatial-frequency components of visual stimuli are each one of the underlying changes in strabismic and anisometropic amblyopia, respectively.

Emergence of vaccine-induced escape mutant of hepatitis B virus with multiple surface gene mutations in a Korean child

The S protein of hepatitis B virus is the principal component of virus envelope and the primary target of anti-HBs response. Mutants or variants that escape neutralization by anti-HBs have been selected during immunoprophylaxis of HBV after birth and liver transplantation. We investigated a case of a Korean child who was vaccinated at birth against hepatitis B and also given hepatitis B immunoglobulin, but nevertheless later became infected with the virus. Hepatitis B virus-specific deoxyribonucleic acid covering the region of genome encoding the predominant "a" determinant of hepatitis surface antigen was amplified using polymerase chain reaction, and the nucleotide sequence was determined. We present for the first time in Korea the independent emergence of an escape mutant with substitution of arginine for glycine at amino acid 145 and proline for glutamate at amino acid 120 in "a" determinant after immunization.

Danchunhwan water extract prevents apoptotic death by peroxynitrite and nitric oxide in human dopaminergic neuroblastoma SH-SY5Y cells

In the present study, the protective effects of Danchunhwan on the cytotoxicity by peroxynitrite and nitric oxide (NO) were investigated in human dopaminergic neuroblastoma SH-SYSY cells. Danchunhwan has been used to treat infarction and cerebrovascular diseases in Oriental medicine for centuries. Cells were pretreated with Danchunhwan and exposed to sodium nitroprusside (SNP), an NO donor, and 3-morpholinosydnonimine (SIN-1) which simultaneously generates NO and superoxide, thus possibly forming peroxynitrite. Exposure of cells to SIN-1 for 24 hr induced 75% of apoptotic cell death, as evaluated by ladder-pattern fragmentation of genomic DNA and characteristic of apoptosis using 4', 6-diamidino-2-phenylinol (DAPI). However, pretreatment of SH-SY5Y cells with Danchunhwan inhibited the apoptotic cell death in a dose-dependent manner. Even though Danchunhwan was washed out after preincubation for 12 hr, cells were still remained to be resistant against cytotoxicity of SIN-1. It also inhibited SIN-1-induced activation of caspase 3-like protease in a dose-dependent fashion. Furthermore, Danchunhwan recovered the levels of intracellular antioxidant system, reduced glutathione (GSH) (83%), which was decreased by the addition of SIN-1 (63%). Taken together, we suggest that Danchunhwan protects human neuroblastoma SH-SY5Y cells from apoptotic death by free radicals including peroxynitrite and NO via generation of antioxidant, GSH.

Steroid-induced acute psychosis in a child with asthma: report of one case

A 5-year-old girl was admitted due to severe asthmatic attack. She was treated with methylprednisolone (40 mg i.v. q6h), aminophylline (loading with 5 mg/kg and maintained with 0.6 mg/kg/hr i.v. drip), nebulized terbutaline sulphate (5 mg q6h), oral procaterol 12.5 micrograms bid, along with oxygen therapy. Acute psychotic reaction with visual hallucination, delusion, panic reaction and myoclonic movement of hands developed on day 3 of admission. The patient had no previous history of psychiatric problems. The theophylline level was 9.89 micrograms/ml at the moment of psychotic reaction. After the dose of methylprednisolone was reduced from 40 mg to 20 mg i.v. q6h and shifted to other anti-asthma treatment by procaterol metered dose inhaler via spacer, the psychotic reaction disappeared a few hours later. The psychotic reaction was thought to be due to steroid therapy since no other causes could explain the psychotic reaction.

Protective effects of morphine in peroxynitrite-induced apoptosis of primary rat neonatal astrocytes: potential involvement of G protein and phosphatidylinositol 3-kinase (PI3 kinase)

Opiates, such as morphine, have been used extensively in the clinical management of pain due to their potent analgesic effect. Astrocytes, representing a major non-neuronal cell population in the CNS, contain opioid receptors that are actively involved in several brain functions. This study was designed to evaluate the effects by which morphine, a preferential mu-opioid receptor agonist, contributes to cytotoxicity of nitric oxide (NO) species, including NO and peroxynitrite (ONOO-), in primary rat neonatal astrocytes. Primary astrocytes isolated from the cerebral cortex of 1- to 2-day-old Sprague-Dawley rats were treated with morphine, naloxone, and 3-morpholinosydnonimine (SIN-1), a donor of peroxynitrite. Morphine significantly protected primary rat astrocytes from apoptosis mediated by sodium nitroprusside, an NO donor, and SIN-1 in a dose-dependent manner, whereas it did not in other types of cells including C6 glioma, RAW 264.7, and HL-60 cells. Moreover, naloxone antagonized the protective effects of morphine on SIN-1-induced apoptosis. Morphine also inhibited the nuclear condensation and fragmentation of SIN-1-treated cells that was antagonized by naloxone pretreatment. The protective role of morphine in SIN-1-induced apoptosis was dependent on an intracellular antioxidant system such as GSH. Furthermore, the effects of morphine on SIN-1-induced cytotoxicity were prohibited by pretreatment with the G(i) protein inhibitor, pertussis toxin, and the phosphatidylinositol 3-kinase (PI3 kinase) inhibitors, wortmannin and LY294002. Taken together, these results suggest that morphine may protect primary rat astrocytes from apoptosis by NO species via the signaling cascades that involve both G protein and PI3 kinase.

ctr1, a gene involved in a signal transduction pathway of the gliding motility in the cyanobacterium Synechocystis sp. PCC 6803

We generated random Tn5 mutations in Synechocystis sp. PCC 6803 in search for genes involved in the signal transduction cascade for the cyanobacterial gliding motility. One of the non-gliding Tn5 mutants, S1-105, had an insertional inactivation in the slr1044 gene encoding a putative methyl-accepting chemotaxis protein. Interposon mutation on the slr1044 (named ctr1) in the bacterium also eliminated gliding motility. In the interposon mutant, the expression of pilA1 was 5-fold decreased compared with that of wild-type and thick pili, that are believed to be the motor for gliding, could not be observed by an electron microscope. Therefore, we suggest that the Ctr1 protein functions as a transducer that regulates the expression of pilA1, and thus is required for the biogenesis of thick pili.

Parvalbumin Expression Is Downregulated in Rat Fast-Twitch Skeletal Muscles during Aging

In this study, the protein expression profile of extensor digitorum longous (EDL) and Soleus (SOL) muscles, representing fast- and slow-twitch skeletal muscles, respectively, was established using high resolution two-dimensional electrophoresis (2-DE). One protein spot was found uniquely expressed in EDL muscle. N-terminal sequence analysis identified the protein as parvalbumin. Parvalbumin is a high affinity calcium binding protein that regulates muscle contraction and relaxation. Our experiments revealed that parvalbumin expression in EDL muscle was down-regulated during aging. In addition, high-intensity exercise could reverse this age-related change. Soleus muscles do not normally express parvalbumin, but high-intensity exercise could ectopically induce its expression in both young and old SOL muscles. We have also confirmed our 2-DE findings by immunohistochemistry on muscle sections. Our results suggest that high-intensity training could be used to improve muscle functions during aging because parvalbumin play an important role in regulating skeletal muscle contraction and relaxation.

Microbiologic aspects of predominant bacteria isolated from the burn patients in Korea

The risk of infection in burns is well-known. In recent decades, the antimicrobial resistance of bacteria isolated from burn patients has increased. For this reason, we have carried out a study of the predominant bacterial profiles and antimicrobial resistance patterns of isolates from a burn center in Korea. A retrospective study was undertaken at Hallym University, Hangang Sacred Heart Hospital to examine the bacterial isolates from the burn patients and to compare the antibiograms of the predominant bacteria isolated from these patients with those of the other wards over a period of 3 years. Pseudomonas aeruginosa was the most common (n=2997, 45.7%) isolate from the burn patients followed by Staphylococcus aureus (n=21261, 19.2%) and Acinetobacter baumannii (n=878, 13.4%). These bacteria, isolated from the burn patients, were almost all higher in antimicrobial resistance rate than those in the non-burn patients (P<0.05). Because these bacteria showed very high resistant rates, they must be avoided in order to control a hospital-acquired infection. Our results seem helpful in providing useful guidelines for choosing effective empiric antimicrobial therapy against bacteria isolated from the burn patients in Korea.

QscR, a modulator of quorum-sensing signal synthesis and virulence in Pseudomonas aeruginosa

The opportunistic pathogenic bacterium Pseudomonas aeruginosa uses quorum-sensing signaling systems as global regulators of virulence genes. There are two quorum-sensing signal receptor and signal generator pairs, LasR-LasI and RhlR-RhlI. The recently completed P. aeruginosa genome-sequencing project revealed a gene coding for a homolog of the signal receptors, LasR and RhlR. Here we describe a role for this gene, which we call qscR. The qscR gene product governs the timing of quorum-sensing-controlled gene expression and it dampens virulence in an insect model. We present evidence that suggests the primary role of QscR is repression of lasI. A qscR mutant produces the LasI-generated signal prematurely, and this results in premature transcription of a number of quorum-sensing-regulated genes. When fed to Drosophila melanogaster, the qscR mutant kills the animals more rapidly than the parental P. aeruginosa. The repression of lasI by QscR could serve to ensure that quorum-sensing-controlled genes are not activated in environments where they are not useful.

Growth plate chondrocytes inhibit neo-angiogenesis -- a possible mechanism for tumor control

Clinically, tumors seldom grow across the articular cartilage and physeal plate. It is believed that avascular cartilage may inhibit the neo-vascularization of tumor spread. The conditioned medium of growth plate chondrocytes resisted the migration of ECV304 by approximately 41% in invasion assay. Growth plate chondrocytes were shown by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay to have an insignificant effect on the viability of human endothelial cells and fibroblasts. However, the proliferation of human endothelial cells was significantly inhibited by growth plate chondrocytes. The inhibitory activity was up to 35% and specific to endothelial cells. Inhibition of blood vessel formation was also demonstrated in the chick chorioallantoic membrane (CAM) assay. These findings demonstrated that growth plate chondrocytes secrete anti-angiogenesis factor(s) which specifically inhibit both the migration and proliferation of endothelial cells.