bluuebunny/crossref_metadata_2025 huggingface dataset:
Enolase-1 as a plasminogen receptor
Authors: Plow Edward F. , Das Riku
Published: May 2009

In this issue of Blood, Wygrecka and colleagues assign a major role to cell-surface enolase-1 as a plasminogen receptor, mediating LPS-induced invasion of monocytes into lungs in mice and humans.
Partially hydrolyzed guar gum supplement reduces high-fat diet increased blood lipids and oxidative stress and ameliorates FeCl3-induced acute arterial injury in hamsters
Authors: Kuo Dar-Chih , Hsu Shih-Ping , Chien Chiang-Ting
Published: May 2009

Increased reactive oxygen species (ROS) and hyperlipidemia can promote arterial thrombus. We evaluated the potential of a partially hydrolyzed guar gum (PHGG) as dietary fiber on lipid profiles and FeCl3-induced arterial thrombosis in the high fat-diet fed hamsters. Our in vitro results found that PHGG is efficient to scavenge O2
-•, H2O2, and HOCl. High fat-diet increased plasma triglyceride, total cholesterol, LDL, VLDL, methylguanidine and dityrosine level and accelerated FeCl3-induced arterial thrombosis formation (from 463 ± 51 to 303 ± 45 sec). Low dose PHGG supplement significantly decreased the total cholesterol, LDL, methylguanidine and dityrosine level and delayed the time for arterial thrombosis formation (528 ± 75 sec). High dose PHGG supplement decreased the level in triglyceride, total cholesterol, LDL and VLDL and further delayed the time for arterial thrombus (671 ± 36 sec). The increased Bax protein and decreased Bcl-2 and HSP-70 protein expression was found in the carotid and femoral arteries of high fat-diet hamsters. Low and high dose of PHGG supplement decreased Bax expression and increased Bcl-2 and HSP-70 protein expression. We found that FeCl3 significantly enhanced intercellular adhesion molecule-1 and 4-hydroxynonenal expression in the endothelial site of damaged artery after 150-sec FeCl3 stimulation. PHGG supplement decreased the endothelial ICAM-1 and 4-hydroxynonenal expression after 150-sec FeCl3 stimulation. Based on these results, we conclude that PHGG supplement can increase antioxidant protein expression and thus decrease oxidative stress induced arterial injury.
Characterization of dengue virus entry into HepG2 cells
Authors: Suksanpaisan Lukkana , Susantad Tharinee , Smith Duncan R
Published: May 2009

Background

Despite infections by the dengue virus being a significant problem in tropical and sub-tropical countries, the mechanism by which the dengue virus enters into mammalian cells remains poorly described.

Methods

A combination of biochemical inhibition, dominant negative transfection of Eps15 and siRNA mediated gene silencing was used to explore the entry mechanism of dengue into HepG2 cells.

Results

Results were consistent with entry via multiple pathways, specifically via clathrin coated pit mediated endocytosis and macropinocytosis, with clathrin mediated endocytosis being the predominant pathway.

Conclusion

We propose that entry of the dengue virus to mammalian cells can occur by multiple pathways, and this opens the possibility of the virus being directed to multiple cellular compartments. This would have significant implications in understanding the interaction of the dengue virus with the host cell machinery.
Telomerase prevents accelerated senescence in glucose-6-phosphate dehydrogenase (G6PD)-deficient human fibroblasts
Authors: Wu Yi-Hsuan , Cheng Mei-Ling , Ho Hung-Yao , Chiu Daniel Tsun-Yee , Wang Tzu-Chien V
Published: May 2009

Fibroblasts derived from glucose-6-phosphate dehydrogenase (G6PD)-deficient patients display retarded growth and accelerated cellular senescence that is attributable to increased accumulation of oxidative DNA damage and increased sensitivity to oxidant-induced senescence, but not to accelerated telomere attrition. Here, we show that ectopic expression of hTERT stimulates telomerase activity and prevents accelerated senescence in G6PD-deficient cells. Stable clones derived from hTERT-expressing normal and G6PD-deficient fibroblasts have normal karyotypes, and display no sign of senescence beyond 145 and 105 passages, respectively. Activation of telomerase, however, does not prevent telomere attrition in earlier-passage cells, but does stabilize telomere lengths at later passages. In addition, we provide evidence that ectopic expression of hTERT attenuates the increased sensitivity of G6PD-deficient fibroblasts to oxidant-induced senescence. These results suggest that ectopic expression of hTERT, in addition to acting in telomere length maintenance by activating telomerase, also functions in regulating senescence induction.
Regulation of multi-organ inflammation in the regulatory T cell-deficient scurfy mice
Authors: Sharma Rahul , Sung Sun-sang Joe , Fu Shu Man , Ju Shyr-Te
Published: May 2009

Scurfy mice display the most severe form of multi-organ inflammation due to total lack of the CD4+Foxp3+regulatory T cells (Treg) resulted from a mutation of the X-linked transcription factor Foxp3. A large repertoire of Treg-suppressible, inflammation-inducing T cells was demonstrated by adoptive transfer experiments usingRag1-/-mice as recipients and by prolongation of lifespan through breeding withFaslpr/lprmutant. Inflammation in the ear, eyes, skin, tail, salivary glands, lungs, stomach, pancreas, liver, small intestine, colon, skeletal muscle, and accessory reproductive organs are identified. Genetic and cellular regulations of specific organ inflammation are described. Sf mice may be useful for the identification of organ-specific antigens and Treg capable of suppressing inflammation in an organ-specific manner. Sf mice are also useful to determine the important inflammation process at the checkpoint after Treg regulation using genetic analysis through breeding.
Downregulation of developmentally regulated endothelial cell locus-1 inhibits the growth of colon cancer
Authors: Zou Xiaolong , Qiao Haiquan , Jiang Xian , Dong Xuesong , Jiang Hongchi , Sun Xueying
Published: May 2009

Developmentally regulated endothelial cell locus-1 (Del1) is an embryonic angiogenic factor expressed in early embryonic endothelial cells, but recently has been found to be expressed in some forms of cancers including colon and breast cancers, and melanoma, and human cancer cell lines. Overexpression of Del1 accelerates tumor growth by enhancing vascular formation, implying Del1 may be a potential target for anti-angiogenic cancer therapy. The study aims to investigate whether downregulation of Del1 could inhibit the growth of tumors established in nude Balb/c mice by subcutaneous implantation of human LS-174T colon cancer cells. The shRNA expression vectors targeting human Del1, and vascular endothelial growth factor (VEGF) were constructed. Gene transfection of Del1-shRNA downregulated expression of Del1 in LS-174T cells in vivo and in vitro, but did not alter the proliferative or survival properties of cells in vitro. Gene transfection of VEGF-shRNA downregulated expression of both VEGF and Del1 in LS-174T cells in vivo and in vitro. Both Del1-shRNA and VEGF-shRNA gene therapies exhibited anti-tumor activities and they also showed a synergistic effect in suppressing growth of colon tumors by anti-angiogenesis and anti-proliferation. Although further investigation to clarify the mechanisms explaining the role of Del1 in tumor growth, and the interaction between VEGF and Del1, is required, the results indicate that downregulation of Del1 presents a potent therapeutic strategy to combat colon cancer.
Persistent H. pylori colonization in early acquisition age of mice related with higher gastric sialylated Lewis x, IL-10, but lower interferon-γ expressions
Authors: Yang Yao-Jong , Yang Hsiao-Bai , Wu Jiunn-Jong , Sheu Bor-Shyang
Published: May 2009

Background

H. pyloriinfection is less prevalent in childhood. This study validated whether the rates ofH. pyloricolonization depend on different acquisition ages, and correlate with the different gastric Lewis antigens or cytokine expressions afterH. pyloriacquisition.

Methods

We applied a young (7-day-old) C57BL/6 mice group (n = 50) and adult (6-week-old) C57BL/6 mice group (n = 50). In each group, 30 mice were challenged withH. pyloriand 20 mice served as naïve control. The success ofH. pyloricolonization was assessed on the 2ndweek and the 8thweek, respectively. The intensity of the Lewis x, sialylated Lewis x(sialyl-Lex), and cytokine expressions, including TNF-α, IFN-γ, IL-6, IL-10, and IL-1β, were immunochemically stained and graded.

Results

On the 2ndweek afterH. pylorichallenge, the colonization rates ofH. pyloriwere similar between the young mice group and the adult mice group (89% vs. 100%,P> 0.05). However, on the 8thweek, theH. pyloricolonization rate was significantly lower in the young mice group than in the adult mice group (53% vs. 95%,P= 0.003). On the 8thweek, the young mice with a persistence ofH. pyloricolonization had higher sialyl-Lex, higher IL-10, and lower IFN-γ than those of the mice that lost colonization during the 2ndto the 8thweek (P< 0.05).

Conclusion

The persistence ofH. pyloricolonization could be an acquisition-age determinant process. AfterH. pyloriexposure at an early acquisition age, the host response with a higher sialyl-Lexand IL-10, but a lower IFN-γ correlates to the consequent persistence ofH. pyloricolonization.
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) interaction with 3' ends of Japanese encephalitis virus RNA and colocalization with the viral NS5 protein
Authors: Yang Shang-Hua , Liu Mei-Lan , Tien Chih-Feng , Chou Shih-Jie , Chang Ruey-Yi
Published: May 2009

Replication of the Japanese encephalitis virus (JEV) genome depends on host factors for successfully completing their life cycles; to do this, host factors have been recruited and/or relocated to the site of viral replication. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a cellular metabolic protein, was found to colocalize with viral RNA-dependent RNA polymerase (NS5) in JEV-infected cells. Subcellular fractionation further indicated that GAPDH remained relatively constant in the cytosol, while increasing at 12 to 24 hours postinfection (hpi) and decreasing at 36 hpi in the nuclear fraction of infected cells. In contrast, the redistribution patterns of GAPDH were not observed in the uninfected cells. Co-immunoprecipitation of GAPDH and JEV NS5 protein revealed no direct protein-protein interaction; instead, GAPDH binds to the 3' termini of plus- and minus-strand RNAs of JEV by electrophoretic mobility shift assays. Accordingly, GAPDH binds to the minus strand more efficiently than to the plus strand of JEV RNAs. This study highlights the findings that infection of JEV changes subcellular localization of GAPDH suggesting that this metabolic enzyme may play a role in JEV replication.
Neuroprotective mechanisms of puerarin in middle cerebral artery occlusion-induced brain infarction in rats
Authors: Chang Yi , Hsieh Cheng-Ying , Peng Zi-Aa , Yen Ting-Lin , Hsiao George , Chou Duen-Suey , Chen Chien-Ming , Sheu Joen-Rong
Published: May 2009

Puerarin, a major isoflavonoid derived from the Chinese medical herb Radix puerariae (kudzu root), has been reported to be useful in the treatment of various cardiovascular diseases. In the present study, we examined the detailed mechanisms underlying the inhibitory effects of puerarin on inflammatory and apoptotic responses induced by middle cerebral artery occlusion (MCAO) in rats. Treatment of puerarin (25 and 50 mg/kg; intraperitoneally) 10 min before MCAO dose-dependently attenuated focal cerebral ischemia in rats. Administration of puerarin at 50 mg/kg, showed marked reduction in infarct size compared with that of control rats. MCAO-induced focal cerebral ischemia was associated with increases in hypoxia-inducible factor-1α (HIF-1α), inducible nitric oxide synthase (iNOS), and active caspase-3 protein expressions as well as the mRNA expression of tumor necrosis factor-α (TNF-α) in ischemic regions. These expressions were markedly inhibited by the treatment of puerarin (50 mg/kg). In addition, puerarin (10~50 μM) concentration-dependently inhibited respiratory bursts in human neutrophils stimulated by formyl-Met-Leu-Phe. On the other hand, puerarin (20~500 μM) did not significantly inhibit the thiobarbituric acid-reactive substance reaction in rat brain homogenates. An electron spin resonance (ESR) method was conducted on the scavenging activity of puerarin on the free radicals formed. Puerarin (200 and 500 μM) did not reduce the ESR signal intensity of hydroxyl radical formation. In conclusion, we demonstrate that puerarin is a potent neuroprotective agent on MCAO-induced focal cerebral ischemia in vivo. This effect may be mediated, at least in part, by the inhibition of both HIF-1α and TNF-α activation, followed by the inhibition of inflammatory responses (i.e., iNOS expression), apoptosis formation (active caspase-3), and neutrophil activation, resulting in a reduction in the infarct volume in ischemia-reperfusion brain injury. Thus, puerarin treatment may represent a novel approach to lowering the risk of or improving function in ischemia-reperfusion brain injury-related disorders.
DDX11L: a novel transcript family emerging from human subtelomeric regions
Authors: Costa Valerio , Casamassimi Amelia , Roberto Roberta , Gianfrancesco Fernando , Matarazzo Maria R , D'Urso Michele , D'Esposito Maurizio , Rocchi Mariano , Ciccodicola Alfredo
Published: May 2009

Background

The subtelomeric regions of human chromosomes exhibit an extraordinary plasticity. To date, due to the high GC content and to the presence of telomeric repeats, the subtelomeric sequences are underrepresented in the genomic libraries and consequently their sequences are incomplete in the finished human genome sequence, and still much remains to be learned about subtelomere organization, evolution and function. Indeed, only in recent years, several studies have disclosed, within human subtelomeres, novel gene family members.

Results

During a project aimed to analyze genes located in the telomeric region of the long arm of the human X chromosome, we have identified a novel transcript family, DDX11L, members of which map to 1pter, 2q13/14.1, 2qter, 3qter, 6pter, 9pter/9qter, 11pter, 12pter, 15qter, 16pter, 17pter, 19pter, 20pter/20qter, Xpter/Xqter and Yqter. Furthermore, we partially sequenced the underrepresented subtelomeres of human chromosomes showing a common evolutionary origin.

Conclusion

Our data indicate that an ancestral gene, originated as a rearranged portion of the primate DDX11 gene, and propagated along many subtelomeric locations, is emerging within subtelomeres of human chromosomes, defining a novel gene family. These findings support the possibility that the high plasticity of these regions, sites of DNA exchange among different chromosomes, could trigger the emergence of new genes.
High-sensitive and rapid detection of Mycobacterium tuberculosis infection by IFN-γ release assay among HIV-infected individuals in BCG-vaccinated area
Authors: Jiang Weimin , Shao Lingyun , Zhang Ying , Zhang Shu , Meng Chengyan , Xu Yunya , Huang Lingli , Wang Yun , Wang Ying , Weng Xinhua , Zhang Wenhong
Published: May 2009

Background

An accurate test for Mycobacterium tuberculosis infection is urgently needed in immunosuppressed populations. The aim of this study was to investigate the diagnostic power of enzyme-linked immunospot (ELISPOT)-based IFN-γ release assay in detecting active and latent tuberculosis in HIV-infected population in bacillus Calmette-Guerin (BCG)-vaccinated area. A total of 100 HIV-infected individuals including 32 active tuberculosis patients were recruited. An ELISPOT-based IFN-γ release assay, T-SPOT.TB, was used to evaluate the M. tuberculosis ESAT-6 and CFP-10 specific IFN-γ response. Tuberculin skin test (TST) was performed for all recruited subjects.

Results

The subjects were divided into group HIV+ATB (HIV-infected individuals with active tuberculosis, n = 32), group HIV+LTB (HIV-infected individuals with positive results of T-SPOT.TB assay, n = 46) and group HIV only (HIV-infected individuals with negative results of T-SPOT.TB assay and without evidence of tuberculosis infection, n = 22). In group HIV+ATB and HIV+LTB, T-SPOT.TB positive rate in subjects with TST <5 mm were 50% (16/32) and 41.3% (19/46), respectively. Individuals in group HIV+ATB and HIV+LTB with CD4+ T cells <500/μl, T-SPOT.TB showed a higher sensitivity than TST (64.5% vs. 22.6% and 62.2% vs. 29.7%, respectively, both P < 0.0001). In addition, the sensitivity of T-SPOT.TB assay in group HIV+ATB increased to >85% in patients with TB treatment for less than 1 month and CD4+ T cells ≥200/μl, while for patients treated for more than 3 months and CD4+ T cells <200/μl, the sensitivity was decreased to only 33.3%. Furthermore, the results could be generated by T-SPOT.TB assay within 24 hours, which was more rapid than TST with 48–72 hours.

Conclusion

ELISPOT-based IFN-γ release assay is more sensitive and rapid for the diagnosis of TB infection in Chinese HIV-infected individuals with history of BCG vaccination, and could be an effective tool for guiding preventive treatment with isoniazid in latently infected people and for TB control in China.
Chitobiose utilization in Borrelia burgdorferi is dually regulated by RpoD and RpoS
Authors: Rhodes Ryan G , Coy Wendy , Nelson David R
Published: May 2009

Background

Borrelia burgdorferi has limited biosynthetic capabilities and must scavenge N-acetylglucosamine (GlcNAc), an essential component of the microbial cell wall, from the surrounding environment. Spirochetes cultured in the absence of free GlcNAc exhibit biphasic growth; however, addition of chitobiose (a dimer of GlcNAc) substitutes for free GlcNAc resulting in a single exponential phase. We evaluated the effect of RpoS and RpoN, the only alternative sigma factors in B. burgdorferi, on biphasic growth and chitobiose utilization in the absence of free GlcNAc. In addition, we investigated the source of GlcNAc in the second exponential phase.

Results

By comparing the growth of wild-type cells to insertional mutants for rpoS and rpoN we determined that RpoS, but not RpoN, partially regulates both biphasic growth and chitobiose utilization. The rpoS mutant, cultured in the absence of free GlcNAc, exhibited a significant delay in the ability to initiate a second exponential phase compared to the wild type and rpoS complemented mutant. Expression analysis of chbC, which encodes the membrane-spanning protein of the chitobiose phosphotransferase system, suggests the delay is due to the inability of the rpoS mutant to up regulate chbC. Furthermore, supplementing GlcNAc starved cultures with high concentrations (75 or 150 μM) of chitobiose resulted in biphasic growth of the rpoS mutant compared to a single exponential phase for the wild type and rpoS complemented mutant. In contrast, growth of the rpoN mutant under all conditions was similar to the wild type. 5' Rapid amplification of cDNA ends (5' RACE) revealed the transcriptional start site for chbC to be 42 bp upstream of the translational start site. Analysis of the chbC promoter region revealed homology to previously described RpoD and RpoS B. burgdorferi promoters. We also determined that yeastolate, a component of the growth medium (BSK-II), is not essential for second exponential phase growth.

Conclusion

Together these results suggest that RpoD and RpoS, but not RpoN, regulate biphasic growth and chitobiose utilization in B. burgdorferi by regulating the expression of the chitobiose transporter (chbC). The data also demonstrate that the second exponential phase observed in wild-type cells in the absence of free GlcNAc is not due to free chitobiose or GlcNAc oligomers present in the medium.
Involvement of RNA-binding protein Hfq in the osmotic-response regulation of invE gene expression in Shigella sonnei
Authors: Mitobe Jiro , Morita-Ishihara Tomoko , Ishihama Akira , Watanabe Haruo
Published: May 2009

Background

The expression of Type III secretion system (TTSS) in Shigella is regulated in response to changes in environmental osmolarity and temperature. Temperature-dependent regulation of virF, the master regulator of TTSS synthesis, is believed to occur at the transcriptional level. We recently demonstrated, however, that TTSS synthesis also involves post-transcriptional regulation of the synthesis of InvE, a target of virF and key regulator of TTSS synthesis. The mRNA levels of invE (virB) are stable at 37°C, but mRNA stability markedly decreases at low temperatures where the TTSS synthesis is tightly repressed. Deletion of hfq, which encodes an RNA chaperone in Gram-negative bacteria, results in the restoration of expression of invE and other TTSS genes at low temperature due to an increase in the stability of invE mRNA. To date, the molecular details of the regulation of TTSS expression in response to osmotic pressure are not known. In the current study, we investigated the mechanism of regulation of TTSS by osmotic pressure.

Results

Transcription of virF, which encodes the master regulator of TTSS expression, was partially repressed under low osmotic conditions. Several lines of evidence indicated that osmolarity-dependent changes in TTSS synthesis are controlled at the post-transcriptional level, through the regulation of InvE synthesis. First, the expression InvE protein was tightly repressed under low osmotic growth conditions, even though invE mRNA transcripts were readily detectable. Second, under low osmotic conditions, invE mRNA was rapidly degraded, whereas deletion of hfq, which encodes an RNA chaperone, resulted in increased invE mRNA stability and the production of InvE protein. Third, the binding of purified Hfq in vitro to invE RNA was stronger in low-salt buffer, as assessed by gel-shift analysis and surface plasmon resonance (Biacore analysis).

Conclusion

Osmolarity-dependent changes in TTSS synthesis in Shigella involve the post-transcriptional regulation of InvE expression, in addition to partial transcriptional activation by virF. The stability of invE mRNA is reduced under low osmotic conditions, similar to the effect of temperature. Deletion of an RNA chaperone gene (hfq) abolished the repression of TTSS synthesis at low osmolarity through a mechanism that involved increased stability of invE mRNA. We propose that the expression of Shigella virulence genes in response to both osmolarity and temperature involves the post-transcriptional regulation of expression of InvE, a critical regulator of TTSS synthesis.
The association of CD81 with tetraspanin-enriched microdomains is not essential for Hepatitis C virus entry
Authors: Rocha-Perugini Vera , Lavie Muriel , Delgrange David , Canton Jonathan , Pillez André , Potel Julie , Lecoeur Cécile , Rubinstein Eric , Dubuisson Jean , Wychowski Czeslaw , Cocquerel Laurence
Published: May 2009

Background

Three percent of the world's population is chronically infected with hepatitis C virus (HCV) and thus at risk of developing liver cancer. Although precise mechanisms regulating HCV entry into hepatic cells are still unknown, several cell surface proteins have been identified as entry factors for this virus. Among these molecules, the tetraspanin CD81 is essential for HCV entry. Interestingly, CD81 is also required for Plasmodium infection. A major characteristic of tetraspanins is their ability to interact with each other and other transmembrane proteins to build tetraspanin-enriched microdomains (TEM).

Results

In our study, we describe a human hepatoma Huh-7 cell clone (Huh-7w7) which has lost CD81 expression and can be infected by HCV when human CD81 (hCD81) or mouse CD81 (mCD81) is ectopically expressed. We took advantage of these permissive cells expressing mCD81 and the previously described MT81/MT81w mAbs to analyze the role of TEM-associated CD81 in HCV infection. Importantly, MT81w antibody, which only recognizes TEM-associated mCD81, did not strongly affect HCV infection. Furthermore, cholesterol depletion, which inhibits HCV infection and reduces total cell surface expression of CD81, did not affect TEM-associated CD81 levels. In addition, sphingomyelinase treatment, which also reduces HCV infection and cell surface expression of total CD81, raised TEM-associated CD81 levels.

Conclusion

In contrast to Plasmodium infection, our data show that association of CD81 with TEM is not essential for the early steps of HCV life cycle, indicating that these two pathogens, while using the same molecules, invade their host by different mechanisms.
Cemented versus non-cemented hemiarthroplasty of the hip as a treatment for a displaced femoral neck fracture: design of a randomised controlled trial
Authors: Vochteloo Anne JH , Niesten DieuDonné , Riedijk Roeland , Rijnberg Willard J , Bolder Stefan BT , Koëter Sander , Hei Keetie Kremers-van de , Gosens Taco , Pilot Peter
Published: May 2009

Background

A discussion is ongoing whether displaced femoral neck fractures in elderly patients should be treated with a non-cemented or a cemented hemiarthroplasty. A recent Cochrane analysis stresses the importance of further research into the relative merits of these techniques. We hypothesise that non-cemented hemiarthroplasty will result in at least the same technical-functional outcome and complication rate, with a shorter operation time.

Methods and design

A randomised controlled multicentre trial will be performed.

The study population consists of 200 patients of 70 years and older. Patients with a displaced femoral neck fracture will be allocated randomly to have a cemented or a non-cemented hemiarthroplasty. Data will be collected preoperatively, immediately postoperatively, and 6 weeks, 3 months and 1 year postoperatively.

The main outcome measures of this study are technical-functional results of the hemiarthroplasty, duration of surgery, complications, and mid-thigh pain. Secondary outcome measures are living conditions at final follow up, self-reported health-related quality of life, and radiological evaluation of the hemiarthroplasty.

Conclusion

A recent Cochrane analysis did not find arguments in favour of either non-cemented or cemented hemiarthroplasty. The forthcoming trial will compare treatment for a displaced femoral neck fracture by cemented versus non-cemented hemiarthroplasty. Our results will be published as soon as they become available.

Trial Registration

Trial Registration Number NTR1508
Analysis of proteins with the 'hot dog' fold: Prediction of function and identification of catalytic residues of hypothetical proteins
Authors: Pidugu Lakshmi S , Maity Koustav , Ramaswamy Karthikeyan , Surolia Namita , Suguna Kaza
Published: May 2009

Background

The hot dog fold has been found in more than sixty proteins since the first report of its existence about a decade ago. The fold appears to have a strong association with fatty acid biosynthesis, its regulation and metabolism, as the proteins with this fold are predominantly coenzyme A-binding enzymes with a variety of substrates located at their active sites.

Results

We have analyzed the structural features and sequences of proteins having the hot dog fold. This study reveals that though the basic architecture of the fold is well conserved in these proteins, significant differences exist in their sequence, nature of substrate and oligomerization. Segments with certain conserved sequence motifs seem to play crucial structural and functional roles in various classes of these proteins.

Conclusion

The analysis led to predictions regarding the functional classification and identification of possible catalytic residues of a number of hot dog fold-containing hypothetical proteins whose structures were determined in high throughput structural genomics projects.
Modeling of solvent-dependent conformational transitions in Burkholderia cepacia lipase
Authors: Trodler Peter , Schmid Rolf D , Pleiss Jürgen
Published: May 2009

Background

The characteristic of most lipases is the interfacial activation at a lipid interface or in non-polar solvents. Interfacial activation is linked to a large conformational change of a lid, from a closed to an open conformation which makes the active site accessible for substrates. While for many lipases crystal structures of the closed and open conformation have been determined, the pathway of the conformational transition and possible bottlenecks are unknown. Therefore, molecular dynamics simulations of a closed homology model and an open crystal structure of Burkholderia cepacia lipase in water and toluene were performed to investigate the influence of solvents on structure, dynamics, and the conformational transition of the lid.

Results

The conformational transition of B. cepacia lipase was dependent on the solvent. In simulations of closed B. cepacia lipase in water no conformational transition was observed, while in three independent simulations of the closed lipase in toluene the lid gradually opened during the first 10–15 ns. The pathway of conformational transition was accessible and a barrier was identified, where a helix prevented the lid from opening to the completely open conformation. The open structure in toluene was stabilized by the formation of hydrogen bonds.

In simulations of open lipase in water, the lid closed slowly during 30 ns nearly reaching its position in the closed crystal structure, while a further lid opening compared to the crystal structure was observed in toluene. While the helical structure of the lid was intact during opening in toluene, it partially unfolded upon closing in water. The closing of the lid in water was also observed, when with eight intermediate structures between the closed and the open conformation as derived from the simulations in toluene were taken as starting structures. A hydrophobic β-hairpin was moving away from the lid in all simulations in water, which was not observed in simulations in toluene. The conformational transition of the lid was not correlated to the motions of the β-hairpin structure.

Conclusion

Conformational transitions between the experimentally observed closed and open conformation of the lid were observed by multiple molecular dynamics simulations of B. cepacia lipase. Transitions in both directions occurred without applying restraints or external forces. The opening and closing were driven by the solvent and independent of a bound substrate molecule.
QDs versus Alexa: reality of promising tools for immunocytochemistry
Authors: Montón Helena , Nogués Carme , Rossinyol Emma , Castell Onofre , Roldán Mònica
Published: May 2009

Background

The unique photonic properties of the recently developed fluorescent semiconductor nanocrystals (QDs) have made them a potential tool in biological research. However, QDs are not yet a part of routine laboratory techniques. Double and triple immunocytochemistries were performed in HeLa cell cultures with commercial CdSe QDs conjugated to antibodies. The optical characteristics, due to which QDs can be used as immunolabels, were evaluated in terms of emission spectra, photostability and specificity.

Results

QDs were used as secondary and tertiary antibodies to detect β-tubulin (microtubule network), GM130 (Golgi complex) and EEA1 (endosomal system). The data obtained were compared to homologous Alexa Fluor 594 organic dyes. It was found that QDs are excellent fluorochromes with higher intensity, narrower bandwidth values and higher photostability than Alexa dyes in an immunocytochemical process. In terms of specificity, QDs showed high specificity against GM130 and EEA1 primary antibodies, but poor specificity against β-tubulin. Alexa dyes showed good specificity for all the targets tested.

Conclusion

This study demonstrates the great potential of QDs, as they are shown to have superior properties to Alexa dyes. Although their specificity still needs to be improved in some cases, QDs conjugated to antibodies can be used instead of organic molecules in routine immunocytochemistry.
Progesterone receptor does not improve the performance and test effectiveness of the conventional 3-marker panel, consisting of estrogen receptor, vimentin and carcinoembryonic antigen in distinguishing between primary endocervical and endometrial adenocarcinomas in a tissue microarray extension study
Authors: Liao Chiung-Ling , Lee Ming-Yung , Tyan Yeu-Sheng , Kok Lai-Fong , Wu Tina S , Koo Chiew-Loon , Wang Po-Hui , Chao Kuan-Chong , Han Chih-Ping
Published: May 2009

Objective

Endocervical adenocarcinomas (ECA) and endometrial adenocarcinomas (EMA) are uterine malignancies that have differing biological behaviors. The choice of an appropriate therapeutic plan rests on the tumor's site of origin. In this study, we propose to evaluate whether PR adds value to the performance and test effectiveness of the conventional 3-marker (ER/Vim/CEA) panel in distinguishing between primary ECA and EMA.

Methods

A tissue microarray was constructed using paraffin-embedded, formalin-fixed tissues from 38 hysterectomy specimens, including 14 ECA and 24 EMA. Tissue microarray (TMA) sections were immunostained with 4 antibodies, using the avidin-biotin complex (ABC) method for antigen visualization. The staining intensity and extent of the immunohistochemical (IHC) reactions were appraised using a semi-quantitative scoring system.

Results

The three markers (ER, Vim and CEA) and their respective panel expressions showed statistically significant (p < 0.05) frequency differences between ECA and EMA tumors. Although the additional ancillary PR-marker also revealed a significant frequency difference (p < 0.05) between ECA and EMA tumors, it did not demonstrate any supplementary benefit to the 3-marker panel.

Conclusion

According to our data, when histomorphological and clinical doubt exists as to the primary site of origin, we recommend that the conventional 3-marker (ER/Vim/CEA) panel is easier, sufficient and appropriate to use in distinguishing between primary ECA and EMA. Although the 4-marker panel containing PR also reveals statistically significant results, the PR-marker offers no supplemental benefit to the pre-existing 3-marker (ER/Vim/CEA) panel in the diagnostic distinction between ECA and EMA.
Varicella vaccination in Europe – taking the practical approach
Authors: Bonanni Paolo , Breuer Judith , Gershon Anne , Gershon Michael , Hryniewicz Waleria , Papaevangelou Vana , Rentier Bernard , Rümke Hans , Sadzot-Delvaux Catherine , Senterre Jacques , Weil-Olivier Catherine , Wutzler Peter
Published: May 2009

Varicella is a common viral disease affecting almost the entire birth cohort. Although usually self-limiting, some cases of varicella can be serious, with 2 to 6% of cases attending a general practice resulting in complications. The hospitalisation rate for varicella in Europe ranges from 1.3 to 4.5 per 100,000 population/year and up to 10.1% of hospitalised patients report permanent or possible permanent sequelae (for example, scarring or ataxia). However, in many countries the epidemiology of varicella remains largely unknown or incomplete.

In countries where routine childhood vaccination against varicella has been implemented, it has had a positive effect on disease prevention and control. Furthermore, mathematical models indicate that this intervention strategy may provide economic benefits for the individual and society. Despite this evidence and recommendations for varicella vaccination by official bodies such as the World Health Organization, and scientific experts in the field, the majority of European countries (with the exception of Germany and Greece) have delayed decisions on implementation of routine childhood varicella vaccination, choosing instead to vaccinate high-risk groups or not to vaccinate at all.

In this paper, members of the Working Against Varicella in Europe group consider the practicalities of introducing routine childhood varicella vaccination in Europe, discussing the benefits and challenges of different vaccination options (vaccination vs. no vaccination, routine vaccination of infants vs. vaccination of susceptible adolescents or adults, two doses vs. one dose of varicella vaccine, monovalent varicella vaccines vs. tetravalent measles, mumps, rubella and varicella vaccines, as well as the optimal interval between two doses of measles, mumps, rubella and varicella vaccines).

Assessment of the epidemiology of varicella in Europe and evidence for the effectiveness of varicella vaccination provides support for routine childhood programmes in Europe. Although European countries are faced with challenges or uncertainties that may have delayed implementation of a childhood vaccination programme, many of these concerns remain hypothetical and with new opportunities offered by combined measles, mumps, rubella and varicella vaccines, reassessment may be timely.
ApoE isoform-dependent changes in hippocampal synaptic function
Authors: Korwek Kimberly M , Trotter Justin H , LaDu Mary Jo , Sullivan Patrick M , Weeber Edwin J
Published: May 2009

The lipoprotein receptor system in the hippocampus is intimately involved in the modulation of synaptic transmission and plasticity. The association of specific apoE isoform expression with human neurodegenerative disorders has focused attention on the role of these apoE isoforms in lipoprotein receptor-dependent synaptic modulation. In the present study, we used the apoE2, apoE3 and apoE4 targeted replacement (TR) mice along with recombinant human apoE isoforms to determine the role of apoE isoforms in hippocampus area CA1 synaptic function. While synaptic transmission is unaffected by apoE isoform, long-term potentiation (LTP) is significantly enhanced in apoE4 TR mice versus apoE2 TR mice. ApoE isoform-dependent differences in LTP induction require NMDA-receptor function, and apoE isoform expression alters activation of both ERK and JNK signal transduction. Acute application of specific apoE isoforms also alters LTP induction while decreasing NMDA-receptor mediated field potentials. Furthermore, acute apoE isoform application does not have the same effects on ERK and JNK activation. These findings demonstrate specific, isoform-dependent effects of human apoE isoforms on adult hippocampus synaptic plasticity and highlight mechanistic differences between chronic apoE isoform expression and acute apoE isoform exposure.
Expressions of IGFBP-5, cFLIP in cervical intraepithelial neoplasia, cervical carcinoma and their clinical significances: a molecular pathology
Authors: Hou Xue-Jing , Zhang You-Zhong , Liu Xin , Meng Li-Hua , Qiao Yun-Bo
Published: May 2009

Background

Insulin-like growth factor binding protein (IGFBPs) have been as potential tumor suppressors in the occurrence and development of tumors. Cellular Fas-associated death domain-like interleukin-1β-converting enzyme (FLICE)-like inhibitory protein (cFLIP) contains a death effect domain (DED), which blocks death receptor pathway and inhibits apoptosis.

Methods

We collected normal cervical tissues from 28 subjects, CIN samples from 37 patients, and cervical cancer tissues from 40 patients. In these samples, we then measured the expression levels of IGFBP-5 and cFLIP via RT-PCR and immunohistochemistry, and we detected the presence of high-risk HPV by Hybrid capture II assays in cervical secretions provided by the subjects.

Results

significant differences in the expression of IGFBP-5 protein among the normal, CIN, and CC tissues (P < 0.05). The highest expression of IGFBP-5 protein was found in CIN stage II and III tissues, whereas the expression of IGFBP-5 in CC samples was decreased relative to controls. The expression level was affected by factors such as clinical stage, pathological differentiation, and lymph node metastasis. Relative to the controls, IGFBP-5 mRNA content was higher in the CC group and lower in the CIN group (P < 0.05). No expression of cFLIP protein or mRNA was detected in normal cervical tissues. However, the degree of pathological changes correlated with increasing expression of cFLIP protein and mRNA, and significant differences were therefore detected between groups (P < 0.05). The HPV infection rates in the CIN and CC groups were much higher than in the normal group (P < 0.05).

Conclusion

IGFBP-5 expression is up-regulated in response to progression of CIN and down-regulated in invasive cervical carcinoma. Detection of IGFBP-5 and cFLIP expression levels, may prove particularly useful for diagnosing and differentiating CIN and CC.
Regulation of catabolic gene expression in normal and degenerate human intervertebral disc cells: implications for the pathogenesis of intervertebral disc degeneration
Authors: Millward-Sadler S Jane , Costello Patrick W , Freemont Anthony J , Hoyland Judith A
Published: May 2009

Introduction

The aim of this study was to compare the effects of tumour necrosis factor-alpha (TNF-α) and interleukin-1-beta (IL-1β) on protease and catabolic cytokine and receptor gene expression in normal and degenerate human nucleus pulposus cells in alginate culture.

Methods

Cells isolated from normal and degenerate nucleus pulposus regions of human intervertebral discs were cultured in alginate pellets and stimulated by the addition of 10 ng/mL TNF-α or IL-1β for 48 hours prior to RNA extraction. Quantitative real-time polymerase chain reaction was used to assess the effect of TNF-α or IL-β stimulation on the expression of matrix metalloproteinase (MMP)-3, -9 and -13, TNF-α, TNF receptor 1 (TNF-R1), TNF receptor 2 (TNF-R2), IL-1α, IL-1β, IL-1 receptor 1 (IL-1R1) and IL-1 receptor antagonist (IL-1Ra).

Results

MMP-3 and MMP-9 gene expressions were upregulated to a greater level by IL-1β than TNF-α. MMP-13 was upregulated by each cytokine to a similar extent. TNF-α and TNF-R2 expressions were upregulated by both TNF-α and IL-β, whereas TNF-R1 expression was not significantly affected by either cytokine. IL-1β and IL-1Ra expressions were significantly upregulated by TNF-α, whereas IL-1α and IL-1R1 were unchanged.

Conclusions

TNF-α does not induce MMP expression to the same degree as stimulation by IL-1β, but it does act to upregulate IL-1β expression as well as TNF-α and TNF-R2. The net result of this would be an increased inflammatory environment and accelerated degradation of the matrix. These results support the hypothesis that, while TNF-α may be an important initiating factor in matrix degeneration, IL-1β plays a greater role in established pathological degradation.
Patient information leaflets on psychotropic drugs: opinions and use by psychiatrists
Authors: Vaitheswaran Sridhar , MacManus Angela , Hamilton Ross
Published: May 2009

Aims and Method

To assess circumstances and frequency of use, opinions and suggestions for improvement from psychiatrists in a teaching hospital on UK Psychiatric Pharmacy Group patient information leaflets for psychotropic drugs. We also sought information from psychiatrists regarding use of alternate sources of information provision for their patients on psychotropic drugs. A questionnaire was designed, piloted and distributed.

Results

Sixty-one psychiatrists were approached, of whom 49 (80%) responded. the most common indications for use were when initiating a new treatment and when information is sought by the individual or their carers. the most common reason for not using these leaflets was lack of awareness of their existence. Although 33 (67%) responders were of the opinion that these leaflets were useful for patients, only a small proportion was using them frequently.

Clinical Implications

Our study suggested increasing awareness among psychiatrists to encourage the use of patient information leaflets. Various other themes to improve their use also emerged including easy accessibility to the patient information leaflets, modification in the content and structure, and recording the provision of patient information leaflets in the case records.
The trouble with NHS psychiatry in England
Authors: John-Smith Paul St , McQueen Daniel , Michael Albert , Ikkos George , Denman Chess , Maier Michael , Tobiansky Robert , Pathmanandam Hemachandran , Davies Teifon , Babu V. Sunil , Thachil Omana , Iqbal Furhan , Rao Ranga
Published: May 2009

In ‘Wake-up call for British psychiatry’ Craddock et al explained how recent attempts to improve psychosocial care for people with mental illness focus on non-specific psychosocial support. This has been at the expense of proper diagnostic assessment and prescription of treatment by psychiatrists aimed at treatment of specific disorders and recovery. They describe a creeping devaluation of psychiatry which is caricatured as narrow, biological, reductionist, oppressive, discriminatory and stigmatising. Some trusts have implemented ‘New Ways of Working for Psychiatrists’ in a way that undermines the central importance of psychiatrists in mental healthcare. Consequently, patients may be treated in secondary care without ever being seen by a psychiatrist. We consider a number of different changes that have interacted in unforeseen ways, with unintended adverse consequences for psychiatric services in England. We aim to continue the debate here.
The ‘Count Me In’ psychiatric in-patient census for 2007 and the elderly: evidence of improvement or cause for concern?
Authors: Shah Ajit
Published: May 2009

The recently published Count Me In 2007 census specifically reported age-standardised admission rates for individuals aged over 65 years from different Black and minority ethnic groups. the standardised admission ratio was higher in the White Irish, other White, White and Black Caribbean, other Asian, Black Caribbean, Black African and other Black ethnic groups; and lower in the White British and Chinese ethnic groups. As this census was undertaken on a single day for all psychiatric in-patients, it measured bed occupancy rather than admission rates and so it was actually referring to standardised bed occupancy ratios. Bed occupancy is a function of admission rates and length of stay. This editorial critically explores factors (including those related to institutional racism) that may affect both admission rates and length of stay, and ultimately bed occupancy, of Black and minority ethnic elders.
The Realization of Partimenti
Authors: Sanguinetti Giorgio
Published: May 2009

A partimento is a linear guide for the improvisation of a keyboard piece. Partimenti were developed for the training of composers in the conservatories of Naples during the eighteenth century. They contain all the information needed for the realization of complete pieces of music, and their practice bestowed on practitioners a fluency in composition unparalleled since then. The Neapolitan masters usually recommended different stages of realization, from the simplest (con le sole consonanze) to highly elaborate textures. The rules for the realization of partimenti have survived in many sources, but they cover only the first stage of realization because the techniques for more advanced realizations were transmitted orally. With the decadence and extinction of the living tradition, the realization of partimenti became a lost art. However, some principles for advanced realization may be inferred from the surviving written realizations, and from the analysis of the partimento in question. Relying on the foundation formed by the rules, and integrating them with these principles, the present article shows some examples of how a present-day musician can create a satisfying realization.