Involved-field irradiation in definitive chemoradiotherapy for T4 squamous cell carcinoma of the esophagus

OBJECTIVES

Definitive concurrent chemoradiotherapy (ccrt) is currently a therapeutic option for locally advanced esophageal cancer. However, clinical practice differs with respect to the target volume for irradiation. The purpose of the present study was to analyze failure patterns and survival, and to determine the feasibility of using involved-field irradiation (ifi) with concurrent chemotherapy for T4 squamous cell carcinoma (scc) of the esophagus.

METHODS

Between January 2003 and January 2013, 56 patients with clinical T4M0 scc of the esophagus received ccrt using ifi. The radiation field included the primary tumour and clinically involved lymph nodes. Target volumes and sites of failure were analyzed, as were treatment-related toxicity and survival time.

RESULTS

In this 56-patient cohort, 13 patients (23.2%) achieved a complete response, and 21 (37.5%) achieved a partial response, for a total response rate of 60.7%. The major toxicities experienced were leucocytopenia and esophagitis, with 14 patients (25.0%) experiencing grade 3 toxicities. At a median follow-up of 34 months, 48 patients (85.7%) had experienced failure: 39 (69.6%) in-field, 7 (12.5%) elective nodal, and 19 (33.9%) distant. Only 1 patient (1.8%) experienced isolated elective nodal failure. The 1-, 2-, and 3-year survival rates were 39.3%, 21.4%, and 12.5% respectively.

CONCLUSIONS

For patients with T4M0 scc of the esophagus, definitive ccrt using ifi resulted in an acceptable rate of isolated elective nodal failure and an overall survival comparable to that achieved with elective nodal irradiation. A limited radiation therapy target volume, including only clinically involved lesions, would therefore be a feasible choice for this patient subgroup.

Perspectives of People with Dementia About Meaningful Activities: A Synthesis

Qualitative studies were synthesized to describe perspectives of people with dementia regarding meaningful activities. Themes of connectedness were identified using a meta-ethnography approach. The theme of being connected with self encompasses engagement for continuity, health promotion, and personal time. The theme of being connected with others includes being with others not to feel alone, doing an activity with others, and meaningful relationships. The theme of being connected with the environment encompasses being connected to one’s familiar environment, community, and nature. This synthesis suggests that connectedness is an important motivation for engagement in daily activities. Findings indicate that identifying the underlying motivation for an individual with dementia to engage in different activities is important for matching a person with activities that will be satisfying. This review may inform the development of interventions for engaging people with dementia in meaningful, daily activities and creating connectedness to self, others, and the environment.

Stress and Coping Associated With Acculturation Among North Korean Defectors

While adapting to a new culture, North Korean defectors may develop their own coping strategies and utilize coping resources to deal with acculturative stress. The purpose of this study was to identify the stress-coping strategies utilized by North Korean defectors. Using semistructured in-depth interviews, three salient themes as the major coping strategies were identified: (a) engagement in meaningful activities, (b) emotional and social support, and (c) personal growth. This study suggested that leisure professionals in South Korea create and provide a variety of recreational programs through which North Korean defectors can engage with host individuals in order to increase their health and well-being.

The importance of culturally meaningful activity for health benefits among older Korean immigrant living in the United States

Research indicates that participation in culturally meaningful activity is beneficial for immigrants' health and well-being, yet older Korean immigrants struggle with accepting new cultural perspectives, which can negatively affect their health and well-being. Using in-depth interviews, this study was designed to capture the value of culturally meaningful activities for health among older Korean immigrants. Three themes were identified: (a) improved psychological well-being, (b) enhanced positive emotions and feelings, and (c) social connections developed with others. The findings suggest that by engaging in various culturally meaningful activities, older Korean immigrants gain a sense of social, cultural, and psychological significance in life. This study also provided evidence that older Korean immigrants maintain and develop their cultural identity through culturally meaningful activities.

Biased signalling and proteinase-activated receptors (PARs): targeting inflammatory disease

Although it has been known since the 1960s that trypsin and chymotrypsin can mimic hormone action in tissues, it took until the 1990s to discover that serine proteinases can regulate cells by cleaving and activating a unique four-member family of GPCRs known as proteinase-activated receptors (PARs). PAR activation involves the proteolytic exposure of its N-terminal receptor sequence that folds back to function as a 'tethered' receptor-activating ligand (TL). A key N-terminal arginine in each of PARs 1 to 4 has been singled out as a target for cleavage by thrombin (PARs 1, 3 and 4), trypsin (PARs 2 and 4) or other proteases to unmask the TL that activates signalling via Gq , Gi or G12 /13 . Similarly, synthetic receptor-activating peptides, corresponding to the exposed 'TL sequences' (e.g. SFLLRN-, for PAR1 or SLIGRL- for PAR2) can, like proteinase activation, also drive signalling via Gq , Gi and G12 /13 , without requiring receptor cleavage. Recent data show, however, that distinct proteinase-revealed 'non-canonical' PAR tethered-ligand sequences and PAR-activating agonist and antagonist peptide analogues can induce 'biased' PAR signalling, for example, via G12 /13 -MAPKinase instead of Gq -calcium. This overview summarizes implications of this 'biased' signalling by PAR agonists and antagonists for the recognized roles the PARs play in inflammatory settings.

Health benefits of serious involvement in leisure activities among older Korean adults

The existing literature suggests that serious engagement in leisure activities leads to happiness, life satisfaction, and successful aging among older adults. This qualitative study was used to examine the benefits of serious involvement in leisure activities among older Korean adults who were members of a sports club. Using an analytic data analysis, we identified three main themes associated with the benefits of serious engagement in leisure activities: 1) the experience of psychological benefits, 2) the creation of social support, and 3) the enhancement of physical health. These themes indicate that, through serious involvement in certain physical activities, participants gain various health benefits, which may contribute to successful aging.

Pathway-selective antagonism of proteinase activated receptor 2

BACKGROUND AND PURPOSE

Proteinase activated receptor 2 (PAR2) is a GPCR associated with inflammation, metabolism and disease. Clues to understanding how to block PAR2 signalling associated with disease without inhibiting PAR2 activation in normal physiology could be provided by studies of biased signalling.

EXPERIMENTAL APPROACH

PAR2 ligand GB88 was profiled for PAR2 agonist and antagonist properties by several functional assays associated with intracellular G-protein-coupled signalling in vitro in three cell types and with PAR2-induced rat paw oedema in vivo.

KEY RESULTS

In HT29 cells, GB88 was a PAR2 antagonist in terms of Ca(2+) mobilization and PKC phosphorylation, but a PAR2 agonist in attenuating forskolin-induced cAMP accumulation, increasing ERK1/2 phosphorylation, RhoA activation, myosin phosphatase phosphorylation and actin filament rearrangement. In CHO-hPAR2 cells, GB88 inhibited Ca(2+) release, but activated G(i/o) and increased ERK1/2 phosphorylation. In human kidney tubule cells, GB88 inhibited cytokine secretion (IL6, IL8, GM-CSF, TNF-α) mediated by PAR2. A rat paw oedema induced by PAR2 agonists was also inhibited by orally administered GB88 and compared with effects of locally administered inhibitors of G-protein coupled pathways.

CONCLUSIONS AND IMPLICATIONS

GB88 is a biased antagonist of PAR2 that selectively inhibits PAR2/G(q/11)/Ca(2+)/PKC signalling, leading to anti-inflammatory activity in vivo, while being an agonist in activating three other PAR2-activated pathways (cAMP, ERK, Rho) in human cells. These findings highlight opportunities to design drugs to block specific PAR2-linked signalling pathways in disease, without blocking beneficial PAR2 signalling in normal physiology, and to dissect PAR2-associated mechanisms of disease in vivo.

De novo prediction of PTBP1 binding and splicing targets reveals unexpected features of its RNA recognition and function

The splicing regulator Polypyrimidine Tract Binding Protein (PTBP1) has four RNA binding domains that each binds a short pyrimidine element, allowing recognition of diverse pyrimidine-rich sequences. This variation makes it difficult to evaluate PTBP1 binding to particular sites based on sequence alone and thus to identify target RNAs. Conversely, transcriptome-wide binding assays such as CLIP identify many in vivo targets, but do not provide a quantitative assessment of binding and are informative only for the cells where the analysis is performed. A general method of predicting PTBP1 binding and possible targets in any cell type is needed. We developed computational models that predict the binding and splicing targets of PTBP1. A Hidden Markov Model (HMM), trained on CLIP-seq data, was used to score probable PTBP1 binding sites. Scores from this model are highly correlated (ρ = −0.9) with experimentally determined dissociation constants. Notably, we find that the protein is not strictly pyrimidine specific, as interspersed Guanosine residues are well tolerated within PTBP1 binding sites. This model identifies many previously unrecognized PTBP1 binding sites, and can score PTBP1 binding across the transcriptome in the absence of CLIP data. Using this model to examine the placement of PTBP1 binding sites in controlling splicing, we trained a multinomial logistic model on sets of PTBP1 regulated and unregulated exons. Applying this model to rank exons across the mouse transcriptome identifies known PTBP1 targets and many new exons that were confirmed as PTBP1-repressed by RT-PCR and RNA-seq after PTBP1 depletion. We find that PTBP1 dependent exons are diverse in structure and do not all fit previous descriptions of the placement of PTBP1 binding sites. Our study uncovers new features of RNA recognition and splicing regulation by PTBP1. This approach can be applied to other multi-RRM domain proteins to assess binding site degeneracy and multifactorial splicing regulation.

A key step in the regulation of mammalian genes is the splicing of the messenger RNA precursor to produce a mature mRNA that can be translated into a particular protein needed by the cell. Through the process of alternative splicing, mRNAs encoding different proteins can be derived from the same primary gene transcript. The regulation of this process plays essential roles in the development of differentiated tissues and is mediated by special pre-mRNA binding proteins. To understand how these proteins control gene expression, one must characterize what they recognize in RNA and identify these binding sites across the genome in order to predict their targets. Models that allow this prediction are essential to understanding developmental regulatory programs and their perturbation by disease causing mutations. In this study, we use statistical methods to build models of RNA recognition by the important splicing regulator PTBP1 and then apply these models to predict PTBP1 regulation of new gene transcripts. We show that PTBP1 has different specificity for RNA than was previously recognized and that its target exons are more diverse than was known before. There are many similar splicing regulators in mammalian cells, and these analyses provide a general framework for the computational analysis of their RNA binding and target identification.

The splicing regulator PTBP2 controls a program of embryonic splicing required for neuronal maturation

We show that the splicing regulator PTBP2 controls a genetic program essential for neuronal maturation. Depletion of PTBP2 in developing mouse cortex leads to degeneration of these tissues over the first three postnatal weeks, a time when the normal cortex expands and develops mature circuits. Cultured Ptbp2(-/-) neurons exhibit the same initial viability as wild type, with proper neurite outgrowth and marker expression. However, these mutant cells subsequently fail to mature and die after a week in culture. Transcriptome-wide analyses identify many exons that share a pattern of mis-regulation in the mutant brains, where isoforms normally found in adults are precociously expressed in the developing embryo. These transcripts encode proteins affecting neurite growth, pre- and post-synaptic assembly, and synaptic transmission. Our results define a new genetic regulatory program, where PTBP2 acts to temporarily repress expression of adult protein isoforms until the final maturation of the neuron. DOI: http://dx.doi.org/10.7554/eLife.01201.001.

Abstract P6-06-25: Usefulness of pretreatment NLR as prognostic factor of late recurrence, 5-year after primary treatment

Background

Prognostic factor and predictive factors are well established in early-stage breast cancer, but less is known about recurrence, especially 5-year after primary treatment. While mortality of breast cancer is from organic dysfunction with metastatic disease, not from the diseased breast itself, still we do not have adequate information about metastatic disease as we do about primary breast cancer itself.

The aim of this study is to investigate of usefulness of pretreatment NLR(neutrophil to lymphocyte ratio) as prognostic factor that can tell risk of recurrence 5- year after primary treatment.

Patients and methods

A retrospective review of invasive breast cancer patients surgically resected between January 2001 and December 2007. Exclusion criteria were as followings: patients with recurrence or death within 5yrs.

Results

A total of 301 patients were included and 13 patients experienced with recurrence after 5 years.

Table 1. Patients' characteristics Total (n = 301) N (%)Age*48.8(±11.4)Age ≤3525(8.3)35< ≤50165(54.8)50<111(36.9)Histology Ductal270(89.7)Lobular7(2.3)Others24(8.0)Tumor size (cm)*2.73(±1.64)T stage T1126(41.9)T2158(52.5)T317(5.6)N stage N0199(66.1)N167(22.3)N220(6.6)N311(3.7)unknown4(1.3)Histologic grade I72(23.9)II110(36.5)III70 (23.3)unknown49(16.3)Estrogen receptor Negative111(36.9)Positive185(61.5)unknown5(1.6)Progesterone receptor Negative129(42.9)Positive167(55.5)Unknown5(1.6)HER-2 Negative196(65.1)Positive98(32.6)unknown7(2.3)Molecular subtype Luminal A136(45.2)Luminal B66(21.9)HER-2 enriched32(10.6)Triple negative60(20.0)unknown7(2.3)Late recur Yes13(4.3)No288(95.7)*mean±SD

Overall average of NLR value was 2.16, median value was 1.83. The average NLR were 2.80±1.68 in patients with recurrences occurred after 5 years and 2.13±1.15 in patients without recurrence. The NLR cutoff value of 1.83 was determined by median value.

In 1.83≤NLR group has a higher incidence of recurrence after 5 years compared with NLR<1.83 group (8yr DFS 99.2% vs. 93.3%, p = 0.021). Especially in luminal A(ER (+) or PR (+), HER-2(-)), 1.83≤NLR group has a higher incidence of recurrence after 5 years compared with NLR<1.83 group (8yr DFS 100% vs. 87.0%, p = 0.015).

Conclusion

We found that pretreatment NLR is associated with late recurrence that occurs after five years. And we suggest that NLR could be used as one of the prognostic factor that can tell about late recurrence, 5-year after primary treatment.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-06-25.

Effects of maltitol and xylitol chewing-gums on parameters involved in dental caries development

AIM

The effects on plaque parameters of sugar free chewing-gums (CG) sweetened with either maltitol or xylitol were assessed to better understand the role polyols can play in dental caries prevention.

MATERIALS AND METHODS

A double-blind, parallel, randomised, controlled study was conducted in China. Subjects (N = 258, age = 13 to 15 years-old) were divided into 4 groups: 2 receiving polyols CG, containing respectively maltitol or xylitol, a group receiving gum base (placebo) and a negative control group not receiving any gum. CG were chewed for 30 days. This corresponds to a 10 g consumption of polyol per day. Plaque parameters (growth, pH, bacteria and insoluble glucans) were evaluated throughout the experimental period.

RESULTS

All parameters studied were significantly modified with gum base compared to no-gum: plaque pH increased; plaque growth, bacteria (S. mutans, S. sobrinus, A. viscosus and Lactobacillus) and insoluble glucans decreased. Maltitol and xylitol CG led similarly to a higher plaque pH (AUC, p⋜0.05) on short (at baseline after the first CG consumption) and long term (after 4 weeks of daily CG consumption), with or without saliva stimulation compared to both control and placebo groups. They led to a decrease in plaque growth (p=0.02) over the experimental period compared to controls. Moreover, they significantly reduced the concentration of 4 cariogenic bacteria species (p⋜0.05) in dental plaque compared to gum base.

CONCLUSION

Sugar free CG sweetened with either maltitol or xylitol can similarly reduce plaque acidogenicity compared to gum base through a decrease in oral bacteria presence. The use of a gum base placebo allowed to isolate effects on parameters involved in dental caries development specific to maltitol and xylitol, and to show these effects were similar.

Abstract P6-07-40: Initial Neutrophil-to-Lymphocyte ratio in primary breast cancer patients: a simple and useful biomarker as prognostic factor

Background: Increasing neutrophil/lymphocyte ratios (NLR) on preoperative blood tests have been associated with worse survival of patients with colorectal, gastric, hepatocellular, pancreatic and lung cancer. However the utility of NLR to predict mortality in breast cancer patients has not been studied. The aim of our study was to determine whether the NLR is predictive of disease specific mortality in breast cancer and subtype-adjusted prognostic effect in breast cancer patients.

Methods: We retrospectively identified all the patients with primary breast cancer diagnosed at Yonsei University Wonju Medical School between January 2000 and June 2011 who underwent primary surgery and completed all phase of their treatment. Breast cancer with infiltrating ductal histology was included and divided into 4 subtypes: Luminal A, Luminal B, Her2-enriched, and basal type. Each immunohistochemical characteristics are as followings: Luminal A: ER and/or PgR positive and negative Her2, Luminal B: ER and/or PgR positive with positive HER2, Her2-enriched: negative ER and PR with positive Her2, and triple negative as basal.

Results: Patients with NLR≥2.5 showed significantly lower 5-year, 10-year breast cancer specific survival than patients with NLR<2.5. (5-year survival; 88.6% vs. 96.4%, p = 0.009, 10-year survival; 84.3% vs. 92.2%, p = 0.006). Cox proportional multivariate hazard model for cancer-specific mortality showed that patients with NLR≥2.5 has hazard ratio 4.71 with 95% confidence interval 1.77–12.53. Further analysis was done according to stratified patients' subgroup with intrinsic subtype. In Luminal A subtype, patients with NLR≥2.5 showed higher mortality rate(p = 0.014), while NLR≥2.5 failed to show statistical significance in the other subtype such as Luminal B, Her2 enriched, and triple negative subtype.

Conclusion: Increased preoperative NLR is a significant prognostic factor in breast cancer specific survival and relevant in Luminal A subtype. This study shows that NLR could be a useful prognostic factor for breast cancer specific survival. And this study suggests that different factors could contribute as prognostic factor to each subtype, such as NLR was significant prognostic factor in Luminal A, while we couldn't find increased NLR is significant in other subtypes.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-07-40.

Photocrosslinking of RNA and photoMet-containing amphiphilic alpha-helical peptides

Discovering RNA-protein interactions: A library of photoMet-containing peptides was synthesized by using an Arg- and Leu-rich alpha-helical amphiphilic peptide. Irradiation of mixtures of these peptides and Rev-responsive element (RRE) hairpin RNA promoted formation of covalent adducts. Analysis of one adduct showed that U26 in the bulged stem is responsible for covalent bond formation with the carbene intermediate. This strategy can provide important structural information about RNA-peptide interactions.

MADS: a new and improved method for analysis of differential alternative splicing by exon-tiling microarrays

We describe a method, microarray analysis of differential splicing (MADS), for discovery of differential alternative splicing from exon-tiling microarray data. MADS incorporates a series of low-level analysis algorithms motivated by the "probe-rich" design of exon arrays, including background correction, iterative probe selection, and removal of sequence-specific cross-hybridization to off-target transcripts. We used MADS to analyze Affymetrix Exon 1.0 array data on a mouse neuroblastoma cell line after shRNA-mediated knockdown of the splicing factor polypyrimidine tract binding protein (PTB). From a list of exons with predetermined inclusion/exclusion profiles in response to PTB depletion, MADS recognized all exons known to have large changes in transcript inclusion levels and offered improvement over Affymetrix's analysis procedure. We also identified numerous novel PTB-dependent splicing events. Thirty novel events were tested by RT-PCR and 27 were confirmed. This work demonstrates that the exon-tiling microarray design is an efficient and powerful approach for global, unbiased analysis of pre-mRNA splicing.

Effects of the addition of electrolyte on liquid infiltration in a hydrophobic nanoporous silica gel

In this letter, we report the experimental results of pressure induced infiltration in the hydrophobic nanopores of a silica gel. The infiltration pressure increases with the prolonged surface treatment time, whereas the infiltration volume is not dependent on the surface coverage. When temperature increases, if the liquid phase is pure water, the infiltration pressure would decrease, which is in agreement with the classic contact angle measurement results at large solid surfaces. As an electrolyte is added, however, the variation in infiltration pressure is negligible over a broad temperature range.

Upper sphincter function during transient lower oesophageal sphincter relaxation (tLOSR); it is mainly about microburps

Transient lower oesophageal sphincter relaxations (tLOSRs) are both a dominant mechanism of reflux and an element of the belch reflex. This study aimed to analyse the interplay between reflux and upper oesophageal sphincter (UOS) activity during meal-induced tLOSRs. Fifteen normal subjects were studied with a solid-state high-resolution manometry assembly positioned to record from the hypopharynx to the stomach and a catheter pH electrode 5 cm above the LOS. Subjects ate a 1000-calorie high-fat meal and were monitored for 120 min in a sitting posture. The relationship among tLOSRs, common cavities, pressure changes within the oesophagus and UOS contractile activity were analysed. A total of 218 tLOSRs occurred among the 15 subjects. The majority (79%) were coupled with UOS relaxation and 84% (145/173) of these occurred in association with a common cavity. Upper oesophageal sphincter relaxation was usually preceded by a pressure change in the oesophagus; however, some relaxations (16%) occurred without a discernable increase in pressure or before the pressure increase began. Acid reflux did not appear to play a role in determining UOS response to tLOSRs. The majority of post-prandial tLOSRs were associated with brief periods of UOS relaxation, likely permissive of gas venting (microburps). Intraoesophageal pressure changes likely modulate this UOS response; however, an anticipatory characteristic was evident in some subjects. Whether or not GORD patients with extra-oesophageal symptoms exhibit an exaggeration of the UOS relaxation response during reflux is yet to be determined.

Use of army weapons and private firearms for suicide and homicide in the region of Basel, Switzerland

OBJECTIVES

Switzerland has one of the highest rates of firearm suicides in the world. International studies show a positive correlation between the rate of households with guns and femicides with guns. Because its defense system requires a militia to keep personal firearms at home, Switzerland has a high rate of households with a gun.

METHODS

Records of suicides in the region of Basel between 1992 and 1996 were reviewed. Suicides with either army weapons or private firearms and suicides by other means were compared. Methods and types of homicides that occurred in the region at the same time were also analyzed.

FINDINGS

Firearm suicides were clearly the most frequent means of suicide. They were also used in 30.0% of domestic homicides, although other means were used at similar rates. Firearms for suicide were mainly used by men, especially army weapons. These men were younger, professionally better qualified, and fewer had ever been treated in one of the local state psychiatric services.

DISCUSSION

The use of firearms for suicide, rather than homicide, and particularly of army weapons by young, well-educated men, requires more attention in debates and informed policy regarding access to firearms and suicide prevention in Switzerland.

SNP2NMD: A database of human single nucleotide polymorphisms causing nonsense-mediated mRNA decay

Elucidating the effects of genetic polymorphisms on genes and gene networks is an important step in disease association studies. We developed the SNP2NMD database for human SNPs (single nucleotide polymorphisms) that result in PTCs (premature termination codons) and trigger nonsense-mediated mRNA decay (NMD). The SNP2NMD Web interfaces provide extensive genetic information on and graphical views of the queried SNP, gene, and disease terms.

AVAILABILITY

SNP2NMD is available from http://variome.net, or directly from http://bioportal.kobic.re.kr/SNP2NMD.

SUPPLEMENTARY INFORMATION

http://bioportal.kobic.re.kr/SNP2NMD/Wiki.jsp?page=Statistics.

SNP@Domain: a web resource of single nucleotide polymorphisms (SNPs) within protein domain structures and sequences

The single nucleotide polymorphisms (SNPs) in conserved protein regions have been thought to be strong candidates that alter protein functions. Thus, we have developed SNP@Domain, a web resource, to identify SNPs within human protein domains. We annotated SNPs from dbSNP with protein structure-based as well as sequence-based domains: (i) structure-based using SCOP and (ii) sequence-based using Pfam to avoid conflicts from two domain assignment methodologies. Users can investigate SNPs within protein domains with 2D and 3D maps. We expect this visual annotation of SNPs within protein domains will help scientists select and interpret SNPs associated with diseases. A web interface for the SNP@Domain is freely available at and from .

Tetracysteine genetic tags complexed with biarsenical ligands as a tool for investigating gap junction structure and dynamics

Gap junctions (GJ) are defined as contact regions between two adjacent cells containing tens to thousands of closely packed membrane channels. Cells dynamically modulate communication through GJ by regulating the synthesis, transport and turnover of these channels. Previously, we engineered a recombinant connexin43 (Cx43) by genetically appending a small tetracysteine peptide motif containing the sequence -Cys-Cys-Xaa-Xaa-Cys-Cys- to the carboxy terminus of Cx43 (Cx43-TC) (3). Cx43-TC was stably expressed in HeLa cells and was specifically labeled by exposing the cells to membrane-permeant non-fluorescent ligands, such as FlAsH (a fluorescein derivative) and ReAsH (a resorufin derivative). Direct correlation of live cell images with high resolution EM detection was possible because bound ReAsH not only becomes fluorescent, but can also be used to initiate the photoconversion of diaminobenzidine (DAB) that causes the localized polymerization of an insoluble osmiophilic precipitate then visible by EM. Cx43-TC GJ's could be labeled with ReAsH and photooxidized to give selectively stained channels. Here, how the development of these tetracysteine tags complexed with appropriate ligands are useful for experiments spanning resolution ranges from light microscopy to electron tomography to molecular purification and detection is described.

5-HT2a receptors in rat sciatic nerves and Schwann cell cultures

Pharmacological approaches and optical recordings have shown that Schwann cells of a myelinating phenotype are activated by 5-HT upon its interaction with the 5-HT(2A) receptor (5-HT(2A)R). In order to further characterize the expression and distribution of this receptor in Schwann cells, we examined rat sciatic nerve and cultured rat Schwann cells using probes specific to 5-HT(2A)R protein mRNA. We also examined the endogenous sources of 5-HT in rat sciatic nerve by employing both histochemical stains and an antibody that specifically recognizes 5-HT. Rat Schwann cells of a myelinating phenotype contained both 5-HT(2A)R protein and mRNA. In the healthy adult rat sciatic nerve, 5-HT(2A)Rs were evenly distributed along the outermost portion of the Schwann cell plasma membrane and within the cytoplasm. The most prominent source of 5-HT was within granules of the endoneurial mast cells, closely juxtaposed to Schwann cells within myelinating sciatic nerves. These results support the hypothesis that the 5-HT receptors expressed by rat Schwann cells in vivo are activated by the release of 5-HT from neighboring mast cells.

Tai chi for treating rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is a chronic, systemic inflammatory autoimmune disease that results in the destruction of the musculoskeletal system. The major goals of treatment are to relieve pain, reduce inflammation, slow down or stop joint damage, prevent disability, and preserve or improve the person's sense of well-being and ability to function. Tai Chi, interchangeably known as Tai Chi Chuan, is an ancient Chinese health-promoting martial art form that has been recognized in China as an effective arthritis therapy for centuries.

OBJECTIVES

To assess the effectiveness and safety of Tai Chi as a treatment for people with RA.

SEARCH STRATEGY

We searched the Cochrane Controlled Trials Register (CCTR), MEDLINE, Pedro and CINAHL databases up to September 2002, using the Cochrane Collaboration search strategy for randomised controlled trials. We also searched the Chinese Biomedical Database up to December 2003 and the Beijing Chinese Academy of Traditional Medicine up to December 2003.

SELECTION CRITERIA

Randomized controlled trials and controlled clinical trials examining the benefits and harms of exercise programs with Tai Chi instruction or incorporating principles of Tai Chi philosophy were selected. We included control groups who received no therapy, sham therapy or another type of therapy.

DATA COLLECTION AND ANALYSIS

Two reviewers determined the studies to be included in this review, rated the methodological quality and extracted data using standardized forms.

MAIN RESULTS

Four trials including 206 participants, were included in this review. Tai Chi-based exercise programs had no clinically important or statistically significant effect on most outcomes of disease activity, which included activities of daily living, tender and swollen joints and patient global overall rating. For range of motion, Tai Chi participants had statistically significant and clinically important improvements in ankle plantar flexion. No detrimental effects were found. One study found that compared to people who participated in traditional ROM exercise/rest programs those in a Tai Chi dance program reported a significantly higher level of participation in and enjoyment of exercise both immediately and four months after completion of the Tai Chi program.

REVIEWERS' CONCLUSIONS

The results suggest Tai Chi does not exacerbate symptoms of rheumatoid arthritis. In addition, Tai Chi has statistically significant benefits on lower extremity range of motion, in particular ankle range of motion, for people with RA. The included studies did not assess the effects on patient-reported pain.

Fluorogenic assay for beta-glucuronidase using microchip-based capillary electrophoresis

Microchip capillary electrophoresis (CE) was used with a model enzyme assay to demonstrate its potential application to combinatorial drug screening. Hydrolysis with beta-glucuronidase of the conjugated glucuronide, fluorescein mono-beta-D-glucuronide (FMG), liberated the fluorescent product, fluorescein. FMG and fluorescein were detected by fluorescence, with excitation and emission at 480 and 520 nm, respectively. Microchip CE was used to separate FMG and fluorescein. Fluorescein production was monitored to assess beta-glucuronidase activity. Michaelis-Menten enzyme kinetics analysis yielded the Km value. The results were compared with those from experiments done by conventional CE. The Km value for beta-glucuronidase with FMG is being reported for the first time as 18 microM. The inhibition of beta-glucuronidase by the competitive inhibitor D-saccharic acid-1,4-lactone (SL) was also determined using microchip CE. Reactions were done with various concentrations of inhibitor and constant beta-glucuronidase and FMG concentrations. A dose-response plot was acquired and the IC50 value for SL was determined to be 3 microM.