A formyl peptide receptor agonist suppresses inflammation and bone damage in arthritis

BACKGROUND AND PURPOSE

Annexin A1 (AnxA1) is an endogenous anti-inflammatory protein and agonist of the formyl peptide receptor 2 (FPR2). However, the potential for therapeutic FPR ligands to modify immune-mediated disease has been little explored. We investigated the effects of a synthetic FPR agonist on joint disease in the K/BxN model of rheumatoid arthritis (RA) and RA fibroblast-like synoviocytes (FLS).

EXPERIMENTAL APPROACH

Arthritis was induced by injection of K/BxN serum at day 0 and 2 in wild-type (WT) or AnxA1(-/-) mice and clinical and histopathological manifestations measured 8-11 days later. WT mice were given the FPR agonist compound 43 (Cpd43) (6 or 30 mg·kg(-1) i.p.) for 4 days. Effects of AnxA1 and Cpd43 on RANKL-induced osteoclastogenesis were assessed in RAW 264.7 cells and human RA FLS and macrophages.

KEY RESULTS

Treatment with Cpd43 before or after the onset of arthritis reduced clinical disease severity and attenuated synovial TNF-α and osteoclast-associated gene expression. Deletion of AnxA1 in mice exacerbated arthritis severity in the K/BxN model. In vitro, Cpd43 suppressed osteoclastogenesis and NFAT activity elicited by RANKL, and inhibited IL-6 secretion by mouse macrophages. In human RA joint-derived FLS and monocyte-derived macrophages, Cpd43 treatment inhibited IL-6 release, while blocking FPR2 or silencing AnxA1 increased this release.

CONCLUSIONS AND IMPLICATIONS

The FPR agonist Cpd43 reduced osteoclastogenesis and inflammation in a mouse model of RA and exhibited anti-inflammatory effects in relevant human cells. These data suggest that FPR ligands may represent novel therapeutic agents capable of ameliorating inflammation and bone damage in RA.

Optimal time window of myelotomy in rats with acute traumatic spinal cord injury: a preliminary study

OBJECTIVES

Pathophysiological mechanisms underlying spinal cord injury (SCI) partially involve edema and formation of a hematoma. Myelotomy seems to be a promising intervention. However, the appropriate timing of myelotomy is still unknown in SCI. Here we aimed to determine the timing of microsurgical myelotomy in an animal model of SCI.

METHODS

The SCI model was contusion-induced with a new york university impactor. Sixty-five adult female rats were randomly divided into the following groups: laminectomy alone (the 'sham group', SG), laminectomy plus contusion (the 'contusion group', CG) or laminectomy plus contusion followed by myelotomy at 8, 24 or 48 h (8 h-MTG [myelotomy-treated group], 24 h-MTG or 48 h-MTG). Functional recovery was evaluated via the open field test and the inclined plane test every week after SCI. The percentage of spared white matter area (SWMA) and ultrastructure characteristics of the injured dorsolateral spinal cord were determined on the 42nd day after SCI.

RESULTS

Compared with the CG, myelotomy at 8 h-MTG or 24 h-MTG greatly improved the BASSO-BEATTIE- BRESNAHAN scores (P<0.008), whereas the 48 h-MTG showed less efficacy (P=0.023). All myelotomy groups showed higher mean angle values in an inclined plane test (P<0.005) and had greater percentages of SWMA than the CG. Rats in the 24 h-MTG showed a higher intra-axonal fraction and myelin fraction than those in 48 h-MTG (P<0.005).

CONCLUSION

Myelotomy up to 48 h after SCI improves recovery in rats. The potential time window of myelotomy may be between 8 and 24 h after SCI.

K/B×N serum transfer arthritis is delayed and less severe in leukaemia inhibitory factor (LIF)-deficient mice

This study is investigating the role of leukaemia inhibitory factor (LIF) in the development of inflammation and joint damage in the mouse K/B×N serum transfer arthritis model. LIF knock-out (LIF(-/-)) mice were generated by mating heterozygote females (LIF(+/-)) with heterozygote males. Arthritis was induced in 8-20-week-old LIF knock-out mice (LIF(-/-)) by intraperitoneal injection of pooled K/B×N sera (50 µl) on days 0 and 2. Clinical disease was scored daily for 6 days. Safranin-O and haematoxylin-stained sections were scored for synovitis, joint space exudate, cartilage degradation and bone damage. RNA was extracted from ankle joints and used to investigate gene expression levels of tumour necrosis factor (TNF)-α, interleukin (IL)-1, LIF, LIF receptor, oncostatin M (OSM), OSM receptor, IL-6 and their common receptor subunit gp130 by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The results show that wild-type mice developed severe clinically overt polyarthritis. In contrast, LIF(-/-) mice showed a more than 50% reduction in clinical arthritis severity. Significantly lower histological scores were observed in LIF(-/-) mice compared to wild-type disease controls. LIF(-/-) mice had histopathological scores that were similar to normal healthy mice. IL-6 subfamily cytokine and receptor subunit expression remained unchanged. The expression levels for IL-6 were reduced significantly in all the diseased mice, whether wild-type or LIF(-/-) mice (P < 0·001), compared to healthy wild-type mice. We conclude that LIF contributes to the development of disease in the K/B×N serum transfer model of arthritis. These results provide further evidence for the role of LIF in inflammation and cartilage bone resorption and provide impetus to test the effects of LIF blockade as a therapeutic strategy in rheumatoid arthritis.

UCP2 -866G/A and Ala55Val, and UCP3 -55C/T polymorphisms in association with type 2 diabetes susceptibility: a meta-analysis study

AIMS/HYPOTHESIS

A meta-analysis was performed to assess the association between the UCP2 -866G/A, UCP2 Ala55Val and UCP3 -55C/T polymorphisms and type 2 diabetes susceptibility.

METHODS

A literature-based search was conducted to identify all relevant studies. The fixed or random effect pooled measure was calculated mainly at the allele level to determine heterogeneity bias among studies. Further analyses were performed that stratified for ethnicity.

RESULTS

We examined 17 publications. Stratified analysis for ethnicity and sensitivity analysis revealed that there was no heterogeneity between studies for these variants. Using an additive model, no significant association of the UCP2 -866G/A polymorphism with type 2 diabetes risk was observed, either in participants of Asian (OR 1.05, 95% CI 0.96, 1.16) or of European (OR 1.03, 95% CI 0.99, 1.07) descent. Neither the UCP2 Ala55Val nor the UCP3 -55C/T polymorphism showed any significant association with type 2 diabetes risk in Europeans (OR 1.04, 95% CI 0.98, 1.09 for Ala55Val; OR 1.04, 95% CI 1.00, 1.09 for -55C/T). In contrast, a statistically significant association was observed for both polymorphisms in participants of Asian descent (OR 1.23, 95% CI 1.12, 1.36 for Ala55Val; OR 1.15, 95% CI 1.03, 1.28 for -55C/T).

CONCLUSIONS/INTERPRETATION

Our meta-analysis suggests that the UCP2 -866G/A polymorphism is unlikely to be associated with increased type 2 diabetes risk in the populations investigated. In contrast, our results indicate that the UCP2 Ala55Val and UCP3 -55C/T polymorphisms may indeed be risk factors for susceptibility to type 2 diabetes in individuals of Asian descent, but not in individuals of European descent. This conclusion warrants confirmation by further studies.

Embryonic-like stem cell derived from adult bone marrow: immature morphology, cell surface markers, ultramicrostructure and differentiation into multinucleated fibers in vitro

Embryonic-like stem cell (ELSC), expressing part of surface markers of human embryonic stem cells, may be a better candidate for cell therapy of degenerative muscular disease than mesenchymal stem cell (MSC). We isolated ELSC and MSC from bone marrow, respectively, and compared their differences in the characteristics and the capacity of myogenic differentiation. Results showed that ELSC could be isolated successfully from 3 adult bone marrow samples by using serum-free medium with 10ng/ml basic fibroblast growth factor (bFGF). At the same cell density, MSC could also be isolated from the same samples by using DMEM/F12 medium containing 10% new cattle serum. However, ELSC appeared as small, morphologically slenderer, upregulated expression of SSEA-4 and ultramicroscopically more immature than MSC derived from the same samples. Immunofluorescent staining and RT-PCR analysis showed ELSC weakly expressed Oct-4, Nanog-3 and Sox-2. Moreover, ELSC and MSC could be induced into long, multinucleated fibers expressing myogenin and myosin heavy chain (MHC) in myogenic differentiation medium, but by day 10, proportion of multinucleated fibers positive for MHC was respectively 25.0%+/-6.9% and 13.8%+/-7.6% in ELSC and MSC culture. These data suggest that bone marrow derived ELSC represent an ideal candidate for cell therapy of degenerative muscular disease.

Growth factors as potential drugs for the sensory epithelia of the ear

The highly ordered structures of the hearing and balance organs of vertebrate ears go through a coordinated sequence of cellular and morphogenetic events. It is to be expected that protein growth factors and other extracellular signals will regulate many events during embryonic development of the ear, including the induction of the ear, the specific induction of sensory epithelia, the proliferation of the cells that form the sensory epithelia, the differentiation of the sensory and supporting cells, and the attraction and maintenance of innervation. After embryonic development, growth factors will support cell survival and innervation of new sensory cells. In damaged sensory epithelia, supplementation of the normal growth factors in these tissues has the potential to influence cellular responses to trauma, to reduce cell death and to promote the replacement of dead cells through renewed proliferation and differentiation, so as to improve hearing and balance health via preventive and restorative treatments. Assessment of the influences of specific growth factors on the sensory epithelia of vertebrate ears is at an early stage: this paper provides a brief account of what we know from studies of normal and experimentally manipulated epithelia, discusses the current questions and suggests directions for future studies.

Chinese medicinal herbs for sore throat

BACKGROUND

Chinese herbal medicines are commonly used to treat sore throat in China and among Chinese people worldwide. Their efficacy in treating sore throat has not previously been systematically reviewed.

OBJECTIVES

To assess the efficacy and safety of Chinese herbal medicines for patients with sore throat.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 3, 2006) which contains the Acute Respiratory Infections Group's specialised register; MEDLINE (1966 to August 2006); EMBASE (1980 to August 2006); AMED (1985 to August 2006); the Chinese Biomedical Database (CBM) (1975 to August 2006), and China National Knowledge Infrastructure (CNKI) (1994 to August 2006).

SELECTION CRITERIA

We only included randomised controlled trials (RCTs) assessing Chinese herbal medicines for the treatment of sore throat with the outcomes of recovery, inefficacy, and adverse events.

DATA COLLECTION AND ANALYSIS

One review author contacted the trial authors of claimed RCTs. Three review authors extracted and analysed the data.

MAIN RESULTS

Seven trials involving 1253 participants were included. All trials were identified as being of methodologically poor quality (C category). All of the Chinese herbal preparations in this review were inadequately characterised and were assessed in one trial only. It is highly likely that there was selection bias or detection bias, or both, in all of the included trials. Conflict of interest may have been another factor in producing a positive result in three studies as the prepared drugs were made in the trial author's hospital. We did not perform a meta-analysis and the results of the studies are reported separately. Three formulations were shown to be superior to the control in improving recovery: Ertong Qingyan Jiere Koufuye was more effective than Fufang Shuanghua Koufuye for acute pharyngitis (OR 1.54, 95% Cl 1.11 to 5.74); Yanhouling mixture was more effective than the gentamicin atomised inhalation for acute pharyngitis (OR 5.39, 95% CI 2.69 to 10.81) for acute pharyngitis; and Qinganlan Liyan Hanpian was more effective than Fufang Caoshanhu Hanpian for chronic pharyngitis (OR 2.25, 95% CI 1.08 to 4.67). Four four formulations were shown to be equal in efficacy to the control.

AUTHORS' CONCLUSIONS

Based on the existing evidence included in this review, the efficacy of Chinese herbal medicine for treating sore throat is controversial and questionable. We cannot recommend any kind of Chinese medical herbal formulation as an effective remedy for sore throat, due to the lack of high quality clinical trials.

How a small DNA virus uses dsRNA but not RNAi to regulate its life cycle

Mouse polyomavirus contains a circular DNA genome, with early and late genes transcribed from opposite strands. At early times after infection, genes encoded from the early transcription unit are predominantly expressed. After the onset of viral DNA replication, expression of genes encoded from the late transcription unit increases dramatically. At late times, late primary transcripts are inefficiently polyadenylated, leading to the generation of multigenomic RNAs that are precursors to mature mRNAs. These transcripts contain sequences complementary to the early RNAs and downregulate early-strand gene expression by inducing RNA editing. Our recent work leads to a model where the production of the multigenomic late RNAs is also controlled by the editing of poly(A) signals, directed by overlapping primary transcripts.

Color removal from textile industry wastewater using composite flocculants

In this study, the decolorization of textile wastewater using composite flocculants was examined. It was composed of Fe(III) flocculants and polydimethyldiallylammonium chloride (PDMDAAC). The color removal efficiency of the composite flocculants was compared with that of individual flocculants, ferric chloride (FeCl3), polyferric chloride (PFC) and PDMDAAC, respectively. The results showed that the composite flocculants were more efficient than individual ones in color removal. The color removal efficiency of the composite flocculants was found to be related to the weight percentage of PDMDAAC (Wp), basicity (B) of PFC and molecular weight (MW) of PDMDAAC. The removal rate is higher at a larger Wp and MW value and lower B value. Chemical oxygen demand (COD) removal from textile wastewater was also investigated in this study. During color removal by the composite flocculants, only up to 20% COD could be removed from the textile wastewater. FeCl3 was then used to further remove the remaining COD from the decolorized wastewater. This two-step treatment of textile wastewater could achieve a 91.6% reduction in COD and an 88.9% reduction in color.

Chinese medicinal herbs for measles

BACKGROUND

Measles is an infectious disease caused by Morbillivirus. Chinese physicians believe that medicinal herbs are effective in alleviating symptoms and preventing complications. Chinese herbal medicines are dispensed according to the particular symptoms.

OBJECTIVES

To assess the effectiveness and possible adverse events of Chinese medicinal herbs in treating measles.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Clinical Trials (CENTRAL) (The Cochrane Library Issue 4, 2005); MEDLINE (1966 to June 2005); EMBASE (1980 to June 2005); the Chinese Biomedical Database (1976 to June 2005); VIP Information (1989 to June 2005); China National Knowledge Infrastructure (CNKI) (1994 to June 2005); and the metaRegister of Controlled Trials was searched for ongoing trials.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in which patients with measles without complications were treated with Chinese medicinal herbs were included.

DATA COLLECTION AND ANALYSIS

The primary outcome measure was death from any cause. The secondary outcome measure was improvement of overall symptoms. The tertiary outcome measure was fever clearance time.

MAIN RESULTS

We identified 28 trials which claimed to use random allocation. Nineteen study authors were contacted by telephone and we discovered that the allocation methods they had used were not actually randomised. Three studies were excluded because the patients experienced complications. We were unable to contact the remaining six authors. These require further assessment and have been allocated to the 'Studies awaiting assessment' section.

AUTHORS' CONCLUSIONS

Two authors independently assessed trial quality and extracted data. We interviewed by telephone the study authors for missing information regarding random allocation of the study process. Some trials allocated the participants according to the sequence they were admitted to the trials, that is to say, by using a pseudo-random allocation method. None of the trials concealed the allocation or blinding method. We hope future randomised controlled trials (RCTs) in this field will be conducted.

Effect of dietary K intake on apical small-conductance K channel in CCD: role of protein tyrosine kinase

We have used Western blot to examine the expression of cSrc protein tyrosine kinase (PTK) and protein tyrosine phosphatase (PTP)-1D in the renal cortex, and the patch-clamp technique to determine the role of PTK in mediating the effect of dietary K intake on the small-conductance K (SK) channel in the cortical collecting duct (CCD). When rats were on a K-deficient (KD) diet for 1, 3, 5, and 7 days, the expression of cSrc increased by 40, 90, 140, and 135%, respectively. In contrast, the expression of cSrc in the renal cortex from rats on a high-K (HK) diet for 1, 2, and 3 days decreased by 40, 60, and 75%, respectively. However, the protein level of PTP-1D was not significantly changed by dietary K intake. The addition of 1 microM herbimycin A increased NP(o), a product of channel number (N) and open probability (P(o)) in the CCD from rats on a normal diet or on a KD diet. The increase in NP(o) was 0.30 (normal), 0.45 (1-day KD), 0.65 (3-day KD), 1.55 (5-day KD), and 1.85 (7-day KD), respectively. Treatment of the CCD with herbimycin A from rats on a KD diet increased NP(o) per patch from the control value (0.7) to 1.4 (1-day KD), 1.6 (3-day KD), 2.6 (5-day KD), and 3.5 (7-day KD), respectively. In contrast, HK intake for as short as 1 day abolished the effect of herbimycin A. Furthermore, the expression of ROMK channels in the renal cortex was the same between rats on a KD diet or on a HK diet. Moreover, treatment with herbimycin A did not further increase NP(o) in the CCDs from rats on a HK diet. We conclude that dietary K intake plays a key role in regulating the activity of the SK channels and that PTK is involved in mediating the effect of the K intake on channel activity in the CCD.

[New progress of surface enhanced Raman spectroscopic studies on a gold electrode in a nonaqueous system]

Based on a highly sensitive new generation confocal microprobe Raman system, the adsorption behavior of thiocyanate (SCN-) on a gold electrode in methanol solution was investigated by SERS for the first time. Preliminary results demonstrated that the interaction between SCN- and the electrode is so strong that its SERS signal can be detected in the whole research potential region (-0.1 V(-)-1.4 V). The orientation change may occur in the potential range -0.6 V-0.7 V. From -0.1 V to -0.6 V SCN- is adsorbed mainly through S end onto Au surface while in the potential range of -0.7 V to -1.2 V it is oriented mainly through N end. The potential dependence of the Raman frequency of nu CN resulted in two different values of electrochemical Stark effect, suggesting the existence of molecular orientation change.

Role of 20-HETE in mediating the effect of dietary K intake on the apical K channels in the mTAL

We have used the patch-clamp technique to study the effect of dietary K intake on the apical K channels in the medullary thick ascending limb (mTAL) of rat kidneys. The channel activity, defined by the number of channels in a patch and the open probability (NPo), of the 30- and 70-pS K channels, was 0.18 and 0.11, respectively, in the mTAL from rats on a K-deficient diet. In contrast, NPo of the 30- and 70-pS K channels increased to 0.60 and 0.80, respectively, in the tubules from animals on a high-K diet. The concentration of 20-hydroxyeicosatetraenoic acid (20-HETE) measured with gas chromatography-mass spectrometry was 0.8 pg/microg protein in the mTAL from rats on a high-K diet and increased significantly to 4.6 pg/microg protein in the tubules from rats on a K-deficient diet. Addition of N-methylsulfonyl-12,12-dibromododec-11-enamide (DDMS) or 17-octadecynoic acid (17-ODYA), agents that inhibit the formation of 20-HETE, had no significant effect on the activity of the 30-pS K channels. However, DDMS/17-ODYA significantly increased the activity of the apical 70-pS K channel from 0.11 to 0.91 in the mTAL from rats on a K-deficient diet. In contrast, inhibition of the cytochrome P-450 metabolism of arachidonic acid increased NPo from 0.64 to 0.81 in the tubules from animals on a high-K diet. Furthermore, the sensitivity of the 70-pS K channel to 20-HETE was the same between rats on a high-K diet and on a K-deficient diet. Finally, the pretreatment of the tubules with DDMS increased NPo of the 70-pS K channels in the mTAL from rats on a K-deficient diet to 0.76. We conclude that an increase in 20-HETE production is involved in reducing the activity of the apical 70-pS K channels in the mTAL from rats on a K-deficient diet.

[Central low frequency hearing loss]

OBJECTIVE

To study the pathogenesis of the bilateral central low frequency hearing loss.

METHODS

Audiologic findings [auditory brainstem response(ABR), evoked otoacoustic emission (EOAE), et al] of 101 cases with bilateral central low frequency hearing loss were studied.

RESULTS

The typical clinical manifestations of bilateral central low frequency hearing loss were normal EOAE which cannot be suppressed by contralateral white noise, abnormal ABR, no acoustic reflex and--SP/AP > 0.44.

CONCLUSIONS

The results suggest that cochlear outer hair cells are normal in function with dysfunction of the cochlear nuclei. The main lesion of the disease are neural pathways related to Acoustic reflex and medial olivo-cochlear efferent nervous system. The cochlear afferent nerve may also be involved.

[Self-assembly of nano-structured silver particle and its surface-enhanced Raman spectroscopic application]

Planar arrays of nano-structured silver particle were self-assembled on poly-lysine modified glass surfaces. SEM characterization indicates that silver particles were assembled as a sub-monolayer. A comparison of the UV/Vis spectra of silver colloid and the arrays demonstrates that the poly-lysine layer showed size selectivity for the self-assembling silver particles. Surface-enhanced FT-Raman spectrum of methylviolegen on the array reveals that Raman scattering in near IR region was mainly enhanced via a chemical enhancement mechanism.

[Cochlear hypoxia and mtDNA deletion: possible correlated factors to cause presbycusis]

OBJECTIVE

To find the relationship among the most common mitochondrial DNA (mtDNA) 4,977 bp deletion, aging and deterioration of acoustic organ and determine the pathologic factors causing mtDNA 4,977 bp deletion.

METHODS

Sixty-seven temporal bones from a presbycusis group, an age-matched control group and a young control group were evaluated. The nested PCR and tri-nested PCR techniques were used to test the presence of mtDNA 4,977 deletion. Computer imaging processing was used to measure the parameters of blood vessels in the internal acoustic meatus.

RESULTS

Temporal bones from patients aged 50 years or over frequently showed mtDNA 4,977 deletions. In presbycusis patients, 17 of 34 ears showed mtDNA 4,977 deletion, whereas only 4 of 19 ears from the age-matched control group showed mtDNA 4,977 deletions. mtDNA 4,977 deletions were often seen in the spiral ganglion and vestibular ganglion neurons. In the presbycusis group, the lumen of the vasa nervosum of the internal auditory meatus showed a more severe reduction in patients with mtDNA 4,977 deletion than in those without deletion.

CONCLUSION

There is a strong correlation between presbycusis and mtDNA 4,977 deletion. We hypothesize that cochlear hypoxia may cause mtDNA 4,977 deletions and other mtDNA mutants which in turn may cause a reduction of mitochondrial oxidative phosphorylation and decreased auditory nerve function. The symptoms of neural presbycusis, however, may appear only after mtDNA metabolism decreases below a specific threshold.

[Two-dimensional surface Raman imaging of a roughened iron electrode in saline solution]

By using a confocal microprobe Raman system and proper surface roughening procedure for iron, the pit corrosion behavior of bare iron electrode in 3.4% NaCl (saline solution) solution has been investigated. The surface-enhanced Raman scattering (SERS) spectra of the corrosion products due to the pit corrosion at positive potential was obtained with high ratio of signal to noise. The application of SERS technique has been extended successfully to the study of iron corrosion. The two-dimensional surface Raman imaging acquired at 660 cm-1 was obtained also with the utility of surface Raman image technique. Results show that different iron oxides should coexist in the pit corrosion region and the distribution of the corrosion products was not uniform.

[Resonance Raman and surface-enhanced Raman spectroscopic study of microperoxidase-11]

The electron transfer and structure of microperoxidase-11 (MP-11) in solution and at electrode/solution interface were studied by electrochemical, resonance Raman and surface-enhanced Raman spectroscopic techniques. Results show that the central iron in heme group was six-coordinated in solution, whereas it was converted to five-coordinated state as MP-11 was adsorbed on the surface of a roughened silver electrode, due to the reorientation of MP-11 molecules. The electrochemical properties of MP-11 were directly affected by the coordination state of heme iron.

Protein-tyrosine phosphatase reduces the number of apical small conductance K+ channels in the rat cortical collecting duct

Previous studies have demonstrated that an increase in the activity of protein-tyrosine kinase (PTK) is involved in the down-regulation of the activity of apical small conductance K(+) (SK) channels in the cortical collecting duct (CCD) from rats on a K(+)-deficient diet (). We used the patch clamp technique to investigate the role of protein-tyrosine phosphatase (PTP) in the regulation of the activity of SK channels in the CCD from rats on a high K(+) diet. Western blot analysis indicated that PTP-1D is expressed in the renal cortex. Application of 1 microm phenylarsine oxide (PAO) or 1 mm benzylphosphonic acid, agents that inhibit PTP, reversibly reduced channel activity by 95%. Pretreatment of CCDs with PAO for 30 min decreased the mean NP(o) reversibly from control value 3.20 to 0.40. Addition of 1 microm herbimycin A, an inhibitor of PTK, had no significant effect on channel activity in the CCDs from rats on a high K(+) diet. However, herbimycin A abolished the inhibitory effect of PAO, indicating that the effect of PAO is the result of interaction between PTK and PTP. Addition of brefeldin A, an agent that blocks protein trafficking from Golgi complex to the membrane, had no effect on channel activity. Moreover, application of colchicine, a microtubule inhibitor, or paclitaxel, a microtubule stabilizer, had no effect on channel activity. In contrast, PAO still reduced channel activity in the presence of brefeldin A, colchicine, or paclitaxel. Furthermore, the effect of PAO on channel activity was absent when the tubules were bathed in 16% sucrose-containing bath solution or treated with concanavalin A. We conclude that PTP is involved in the regulation of the activity of SK channels and that inhibition of PTP may facilitate the internalization of the SK channels.

[Dynamic analysis of junctional sequences of T cell receptor (TCR) delta and gamma gene rearrangement in childhood with acute lymphoblastic leukemia]

OBJECTIVE

To explore the junctional sequence difference of T cell receptor delta and gamma gene rearrangement in childhood acute lymphoblastic leukemia (ALL) at diagnosis, complete remission (CR) and relapse.

METHODS

By using the T-vector molecular cloning and sequencing and polymerase chain reaction, the junctional sequences of TCRdeltaV-D and TCRgammaV-J were dynamically analyzed in 34 bone marrow samples of ALL.

RESULTS

The junctional sequence of TCR delta, gamma gene showed significant difference and regularity before and after remission and during relapsed periods. The sequence of TCRdeltaV-D were analyzed in 24 samples from ALL. Among them, the intact Vdelta2 and 5'Ddelta3 sequences were observed in 10 samples at diagnosis, of which 7 samples had T-->C mutation in Ddelta3 nonamer sequence. The deletions of rearranged Vdelta2, 5'Ddelta3 and Ddelta3 haptamer sequences were found in 11 complete remission (CR) samples with ALL, but none had T-->C mutation in Ddelta3 nonamer sequence. The deletion rate of Vdelta2 or Ddelta3 sequences and the T-->C mutation in Ddelta3 nonamer sequence were extremely differed between samples at diagnosis and in remission (calculate exact probabilities P = 0.001). The junctional rearrangement sequence of 5'Ddelta3 sequences tended to remain intact in 3 relapsed samples. The findings of TCRgammaV-J sequences were similar to that of TCRdeltaV-D in 10 ALL patients.

CONCLUSION

The difference of TCRdeltaV-D and TCRgammaV-J junctional sequences were related to the development, therapeutic effectiveness and outcome in ALL.

Development of Weather-Dependent Flow Requirements for River Temperature Control

/ Streamflow influences biological processes, habitat, and ecological integrity of streams in a number of vital ways. The establishment of weather-dependent minimum flows is essential to the protection of the aquatic environment and wildlife habitat from the adverse impacts of high water temperatures and to the effective utilization of the assimilative capacity of instream flows. In this study, weather-dependent flow requirements for summer river temperature control are derived from quantitative temperature-flow relationships. Correlation and regression of historical data and an analytical solution to the basic heat balance equation are employed to quantify the impacts of stream flow on river temperatures. Five-year continuous field measurements from the Platte River, Nebraska, USA, are used to illustrate the practical application in water-quality management. The methods and results demonstrate the feasibility of temperature control through streamflow management to meet water temperature standards and protect the aquatic biota by setting the appropriate weather-related minimum river discharges. The flow requirements are evaluated by a comparison with a critical discharge. Information provided in this paper will assist in planning streamflow regulation, design of river and reservoir operations, and application of water-quality criteria in environmental management.KEY WORDS: River discharges; Flow management; Habitat; Water quality; Weather; Wildlifehttp://link.springer-ny.com/link/service/journals/00267/bibs/24n4p529.html</HEA

[Progress of surface enhanced Raman spectroscopic studies in nonaqueous systems]

In this report, we describe the applications and theoretical aspects of SERS phenomenon in nonaqueous systems, which mainly involves the structure of solid/nonaqueous system, the adsorption of some neutral and organic molecules, inorganic ions and other complex compound molecules, the process and mechanism of some electrochemical oxidation reduction reactions in organic solvents etc.. In this review, we also depict the similarities and differences in SER spectra of aqueous and non-aqueous systems.