[Abuse of "pheticol" and its interference to the analysis of methamphetamine]

The study was to eliminate interference from ephedrine in the analysis of methamphetamine. The extraction procedure for methamphetamine was modified to include an oxidation step (2 ml urine specimen was treated with 0.5 ml of 1 mol/L phosphate buffer (pH 6.8) and 0.5 ml 0.3 mol/L sodium periodate). Results showed that ephedrine could be oxidized in the presence of periodate ions into smaller fragments while leaving methamphetamine intact. It is recommended that specimens be treated with sodium periodate prior to extraction in order to eliminate any interference caused by ephedrine.

Independent dose calculations for the corvus MLC IMRT

Two independent dose calculation methods have been explored to validate MLC-based IMRT plans from the NOMOS CORVUS system. After the plan is generated on the CORVUS planning system, the beam parameters are imported into an independent workstation. The beam parameters consist of intensity maps at each gantry angle. In addition, CT scans of the patient are imported into the independent workstation to obtain the external contour of the patient. The coordinate system is defined relative to the alignment point chosen in the CORVUS plan. The 2 independent calculation methods are based on a pencil beam kernel convolution and a Clarkson-type differential scatter summation, respectively. The pencil beam data for a 1 x 1-cm beam, as formed by the multileaf collimator, were measured for the 6-MV photon beam from a Siemens PRIMUS linear accelerator using film dosimetry. In the pencil beam method, the dose at a point is calculated using the depth and off-axis distance from a given pencil beam, corrected for beam intensity. The scatter summation method used the conversion of measured depth dose data into scatter maximum ratios. In this method, the differential scatter from each pencil beam is corrected for the beam intensity. Isodose distributions were generated using the independent dose calculations and compared to the CORVUS plans. Although isodose distributions from both methods show good agreement with the CORVUS plan, our implementation of the differential scatter summation approach seems more favorable. The 2 independent dose calculation algorithms are described in this paper.

[Distribution of F13A01, FESFPS and vWA loci in ten minority populations in Yunnan of China]

The short tandem repeats (STR) is a kind of DNA sequence formed repeatedly and connectively subjected to a core unit of several base pairs. The non-interfered multi-PCR was applied with 3 loci in the same reaction system. By using the technique of denaturing polyacrylamide gel electrophoresis and silver stain, the allele frequencies distributions of 3 loci: F13A01, FESFPS and vWA in 10 minority populations only resided in Yunnan Province: Bai, Dai, Achang, Jingpo, Deang, Lahu, Bulang, Hani, Pumi and Jino. A satisfactory result was obtained and some significant genetic differences were noticed in different populations.

[A novel erythroid differentiation related gene EDRF1 upreguated globin gene expression in HEL cells]

OBJECTIVE

To observe the differentiation-inducing properties of the novel erythroid differentiation related gene EDRF1, and demonstrate its functioning pathway involved in regulation of alpha- and gamma-globin gene expression.

METHODS

EDRF1 sense and antisense constructs were transfected into HEL cells, then the expression of globin and erythropoietin receptor gene was identified by Northern blot analysis. RT-PCR and electrophoresis mobility shift assay (EMSA) were carried out to monitor the expression and DNA-binding activity of erythroid specific transcription factor GATA-1 and NF-E2.

RESULTS

In HEL cells with transfection of sense expression carrier, the experssion of EDRF1 mRNA was upregulated. In HEL cells with transfection of antisense expression carrier, the experession of EDRF1 mRNA was downregulated. In HEL cells with overexpression of EDRF1, production of alpha-globin was increased. In antisense EDRF1 overexpressed HEL cells, significant loss of alpha- and gamma-globin mRNA synthesis was observed. The expression of erythropoietin receptor was unchanged in HEL cells transfected with EDRF1 sense and antisense expression carriers. No significant change was found in expression of transcription factors GATA-1 and NF-E2 in HEL cells transfected with empty carrier, sense expression carrier, and antisense expression carrier. However, the transcription activity of GATA-1 was severely impaired. Expression of erythropoietin receptor gene was not influenced by EDRF1 gene overexpression.

CONCLUSION

EDRF1 regulates alpha- and gamma-globin gene synthesis by modulating DNA-binding activity of GATA-1 transcription factor. Overexpression and underexpression of EDRF1 do not significantly regulate the expression of GATA-1 and NF-E2 mRNA. Monitoring the EPOR signal pathway is not the mechanism by which EDRF1 influences the differentiation of erythrocyte.

Medical management of postoperative complications of inflammatory bowel disease: pouchitis and Crohn's disease recurrence

Surgical intervention is often required for patients with inflammatory bowel disease. Total proctocolectomy with ileal pouch-anal anastomosis is the surgical treatment of choice for patients with ulcerative colitis. The main long-term complication of this surgery is pouchitis, with 10-year cumulative incidence rates between 24% and 46%. For patients with Crohn's disease, postoperative recurrence is a significant problem, with clinical recurrence rates as high as 55% at 5 years and 76% at 15 years. Increasing evidence suggests that postoperative medical therapy has the potential to decrease the risk of postoperative Crohn's disease recurrence.

Affinity and Western blotting reveal homologies between ovine intervertebral disc serine proteinase inhibitory proteins and bovine pancreatic trypsin inhibitor

The objective of this study was to assess any similarities between ovine intervertebral disc (IVD) serine proteinase inhibitory proteins (SPIs) and known mammalian IVD SPIs. Ovine IVDs were dissected into the annulus fibrosus and nucleus pulposus and the tissue finely diced then extracted with 4 M guanidine hydrochloride. The tissue extracts were subjected to caesium chloride density gradient ultracentrifugation to separate the large high buoyant density (rho > 1.5 g/mL) proteoglycans from the SPI proteins of low buoyant density (rho < 1.33 g/mL). The top two ultracentrifuge fractions containing the SPIs of interest were subjected to enzyme linked immunosorbent analysis (ELISA) and also examined by Western and Affinity blotting using an antibody to bovine pancreatic trypsin inhibitor and biotinylated trypsin respectively for detection and an alkaline phosphatase 5-bromo-4-chloro-3-indolyl phosphate/nitro blue tetrazolium system for visualisation. The major SPI proteins present in the Western and Affinity blots were 34-36 kDa species, minor 12 and 16, and 85 and 120 kDa species were also present. Qualitatively similar results were obtained for each respective tissue zone of the lumbar and lumbosacral disc specimens examined. Densitometric analysis of the major 34-36 kDa SPI bands visualised on Western and Affinity blots using NIH 1.61.1 image analysis software indicated that lumbar IVD samples contained higher levels of this SPI species than lumbosacral IVD samples. ELISA confirmed that lumbar IVD extracts contained quantitatively higher levels of BPTI equivalents per g of tissue extracted than lumbosacral IVDs. This study therefore has demonstrated that the ovine disc contains a range of SPI species which share some homology with bovine pancreatic trypsin inhibitor and in this respect are similar to SPIs previously demonstrated in canine IVDs.

The biosynthetic gene cluster for the anticancer drug bleomycin from Streptomyces verticillus ATCC15003 as a model for hybrid peptide-polyketide natural product biosynthesis

The hybrid peptide-polyketide backbone of bleomycin (BLM) is assembled by the BLM megasynthetase that consists of both nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) modules. BlmIX/BlmVIII/BlmVII constitute a natural hybrid NRPS/PKS/NRPS system, serving as a model for both hybrid NRPS/PKS and PKS/NRPS systems. Sequence analysis and functional comparison of domains and modules of BlmIX/BlmVIII/BlmVII with those of nonhybrid NRPS and PKS systems suggest that (1) the same catalytic sites appear to be conserved in both hybrid NRPS-PKS and nonhybrid NRPS or PKS systems, with the exception of the KS domains in the hybrid NRPS/PKS systems that are unique; (2) specific interpolypeptide linkers may play a critical role in intermodular communication to facilitate transfer of the growing intermediates between the interacting NRPS and/or PKS modules; and (3) posttranslational modification of the BLM megasynthetase has been accomplished by a single PPTase with a broad substrate specificity toward the apo forms of both acyl carrier proteins (ACPs) and peptidyl carrier proteins (PCPs).

The ocular albinism type 1 gene product is an N-glycoprotein but glycosylation is not required for its subcellular distribution

The ocular albinism type 1 (OA1) gene product is a membrane glycoprotein that may play a role in controlling melanosome growth and maturation. A number of mutations in the OA1 gene lead to ocular albinism due at least in part to retention of the aberrant protein in the endoplasmic reticulum. To examine whether N-glycosylation plays a role in the post-translational trafficking of the Oa1 protein, we constructed a series of mutant mouse Oa1 cDNAs encoding an Oa1-green fluorescent protein fusion in which some or all of the potential glycosylation sites were eliminated by site-directed mutagenesis. Biochemical studies in transfected cells treated with tunicamycin and peptide:N-glycosidase F suggest that asparagine at amino acid 106 is essential for N-glycosylation of the protein. Mutation at amino acid 106 that eliminated glycosylation did not affect the endo/lysosomal distribution of the Oa1 protein in either COS cells or cultured murine melanocytes.

Transparency of an overdense plasma layer

The transition from opacity to transparency of overdense plasma layers for the propagation of high-intensity laser pulses of circular polarization is investigated theoretically and by simulation. We discuss in detail the regions where stationary solutions exist and therefore the plasma layer is opaque. We find that the opacity depends not only on the electron density and the laser intensity but also on the thickness of the plasma layer. We also discuss the overlap region where both transparency and opacity are possible and how it depends on the history. Ion acceleration is studied in both the opacity region and the transparency region.

A randomized clinical trial of ciprofloxacin and metronidazole to treat acute pouchitis

Metronidazole is effective for the treatment of acute pouchitis after ileal pouch-anal anastomosis, but it has not been directly compared with other antibiotics. This randomized clinical trial was designed to compare the effectiveness and side effects of ciprofloxacin and metronidazole for treating acute pouchitis. Acute pouchitis was defined as a score of 7 or higher on the 18-point Pouchitis Disease Activity Index (PDAI) and symptom duration of 4 weeks or less. Sixteen patients were randomized to a 2-week course of ciprofloxacin 1,000 mg/d (n = 7) or metronidazole 20 mg/kg/d (n = 9). Clinical symptoms, endoscopic findings, and histologic features were assessed before and after therapy. Both ciprofloxacin and metronidazole produced a significant reduction in the total PDAI score as well as in the symptom, endoscopy, and histology subscores. Ciprofloxacin lowered the PDAI score from 10.1+/-2.3 to 3.3+/-1.7 (p = 0.0001), whereas metronidazole reduced the PDAI score from 9.7+/-2.3 to 5.8+/-1.7 (p = 0.0002). There was a significantly greater reduction in the ciprofloxacin group than in the metronidazole group in terms of the total PDAI (6.9+/-1.2 versus 3.8+/-1.7; p = 0.002), symptom score (2.4+/-0.9 versus 1.3+/-0.9; p = 0.03), and endoscopic score (3.6+/-1.3 versus 1.9+/-1.5; p = 0.03). None of patients in the ciprofloxacin group experienced adverse effects, whereas three patients in the metronidazole group (33%) developed vomiting, dysgeusia, or transient peripheral neuropathy. Both ciprofloxacin and metronidazole are effective in treating acute pouchitis with significant reduction of the PDAI scores. Ciprofloxacin produces a greater reduction in the PDAI and a greater improvement in symptom and endoscopy scores, and is better tolerated than metronidazole. Ciprofloxacin should be considered as one of the first-line therapies for acute pouchitis.

[The status and prospects of X-ray photographs marking technology]

This article introduces three different marking technologies used in clinical radiation photography at present and their respective theories, their advantages and disadvantages, analyzes the space-time and technology conditionality of different marking technologies in selecting mark messages. In the future, new marking technology will be fused with the cassette into one and will contain message as much as possible on photograph marks in order to satisfy the need of technicians and doctors.

Independent dose calculations for the PEACOCK System

An independent dose calculation method has been developed to validate intensity-modulated radiation therapy (IMRT) plans from the NOMOS PEACOCK System. After the plan is generated on the CORVUS planning system, the beam parameters are imported into an independent workstation. The beam parameters consist of intensity maps at each gantry angle and each arc position. In addition, CT scans of the patient are imported into the independent workstation to obtain the external contour of the patient. The coordinate system is defined relative to the alignment point chosen in the CORVUS plan. The independent calculation uses the pencil beam data viz tissue maximum ratio (TMR) and beam profiles for a single 1 x 0.8-cm beamlet formed by the NOMOS multileaf intensity-modulating collimator (MIMiC) leaf. The pencil beam data were measured for the 6-MV photon beam from Siemens PRIMUS linear accelerator using film dosimetry. The dose at a point is calculated using the depth and off-axis distance from a given pencil beam, corrected for its beam intensity. Isodose distributions are generated using the independent dose calculations and compared to the CORVUS plans. Isodose distributions show good agreement with the CORVUS plans for a number of clinical cases. The independent dose calculation algorithm is described in this paper.

Comparative study between IMRT with NOMOS BEAK and linac-based radiosurgery in the treatment of intracranial lesions

A comparative study was undertaken to examine intracranial irradiation using intensity-modulation radiation therapy (IMRT) and linear accelerator-based radiosurgery. The IMRT was examined using the Peacock system with a BEAK attachment. A clinical case involving a metastatic brain lesion, treated with 3 radiosurgery isocenters, was planned for IMRT. The radiosurgery was planned using the Leibinger planning system. The IMRT was planned using the CORVUS planning system. The CORVUS planning system uses an inverse planning algorithm, a recent development in radiotherapy. Isodose distributions and dose volume histograms were generated and compared. Analysis of the dosimetry shows that the dose conformity and homogeneity within the target using the RTOG guidelines are superior for IMRT. The advantages of IMRT using inverse planning system include the ease of planning and execution of treatment, especially for cases that involve concave targets that require multiple isocenters using radiosurgery.

Tehao functions in the Toll pathway in Drosophila melanogaster: possible roles in development and innate immunity

Toll and related proteins play important roles in innate immunity in both invertebrates and vertebrates. In Drosophila melanogaster, Tehao shares a striking similarity in its intracellular domain with Toll. In this paper, we show that Tehao is expressed throughout development and appears to be glycosylated. In transiently transfected cells, Tehao activated both Dorsal and the transcription of endogenous drosomycin and metchnikowin genes. Purified recombinant Tehao interacted specifically in vitro not only with the Pelle protein kinase, but also with the Toll intracytoplasmic domain. Remarkably, Tehao was found to activate Dorsal-dependent transcription in a synergistic manner with Toll, as well as Pelle in co-transfected cells. Thus, Tehao, alone or with Toll as a multimeric complex, has the potential to participate in both the development and innate immune responses of Drosophila.

Roles for beta(pat-3) integrins in development and function of Caenorhabditis elegans muscles and gonads

Heterodimeric integrin receptors for extracellular matrix (ECM) play vital roles in bidirectional signaling during tissue development, organization, remodeling, and repair. The beta integrin subunit cytoplasmic domain is essential for transmission of many of these signals and overexpression of an unpaired beta tail in cultured cells inhibits endogenous integrins. Unlike vertebrates, which have at least nine beta subunit genes, the nematode Caenorhabditis elegans expresses only one beta subunit (betapat-3), and a null mutation in this gene causes embryonic lethality. To determine the functions of integrins during larval development and in adult tissues, we have taken a dominant negative approach by expression of an HA-betatail transgene composed of a hemagglutinin (HA) epitope tag extracellular domain connected to the betapat-3 transmembrane and cytoplasmic domains. Expression of this transgene in muscle and gonad, major sites of integrin expression, caused a variety of phenotypes dependent on the level of transgene expression. Abnormalities in body wall and sex muscles led to uncoordinated movement and egg-laying defects. Significant anomalies in migration and pathfinding were caused by tissue-specific expression of HA-betatail in the distal tip cells (DTC), the cells that direct gonad morphogenesis. A pat-3 gene with Tyr to Phe mutations in the cytoplasmic domain was able to rescue pat-3 null animals but also showed DTC migration defects. These results show that betapat-3 plays important roles in post-embryonic organogenesis and tissue function.

Stimulation of eukaryotic flap endonuclease-1 activities by proliferating cell nuclear antigen (PCNA) is independent of its in vitro interaction via a consensus PCNA binding region

Interaction between human flap endonuclease-1 (hFEN-1) and proliferating cell nuclear antigen (PCNA) represents a good model for interactions between multiple functional proteins involved in DNA metabolic pathways. A region of 9 conserved amino acid residues (residues Gln-337 through Lys-345) in the C terminus of human FEN-1 (hFEN-1) was shown to be responsible for the interaction with PCNA. Our current study indicates that 4 amino acid residues in hFEN-1 (Leu-340, Asp-341, Phe-343, and Phe-344) are critical for human PCNA (hPCNA) interaction. A conserved PCNA interaction motif in various proteins from assorted species has been defined as Q(1)X(2)X(3)(L/I)(4)X(5)X(6)F(7)(F/Y)(8), although our results fail to implicate Q(1) (Gln-337 in hFEN-1) as a crucial residue. Surprisingly, all hFEN-1 mutants, including L340A, D341A, F343A, and F344A, retained hPCNA-mediated stimulation of both exo- and flap endonuclease activities. Furthermore, our in vitro assay showed that hPCNA failed to bind to the scRad27 (yeast homolog of FEN-1) nuclease. However, its nuclease activities were significantly enhanced in the presence of hPCNA. Four additional Saccharomyces cerevisiae scRad27 mutants, including multiple alanine mutants and a deletion mutant of the entire PCNA binding region, were constructed to confirm this result. All of these mutants retained PCNA-driven nuclease activity stimulation. We therefore conclude that stimulation of eukaryotic hFEN-1 nuclease activities by PCNA is independent of its in vitro interaction via the PCNA binding region.

Archaeoglobus fulgidus RNase HII in DNA replication: enzymological functions and activity regulation via metal cofactors

RNA primer removal during DNA replication is dependent on ribonucleotide- and structure-specific RNase H and FEN-1 nuclease activities. A specific RNase H involved in this reaction has long been sought. RNase HII is the only open reading frame in Archaeoglobus fulgidus genome, while multiple RNases H exist in eukaryotic cells. Data presented here show that RNase HII from A. fulgidus (aRNase HII) specifically recognizes RNA-DNA junctions and generates products suited for the FEN-1 nuclease, indicating its role in DNA replication. Biochemical characterization of aRNase HII activity in the presence of various divalent metal ions reveals a broad metal tolerance with a preference for Mg(2+) and Mn(2+). Combined mutagenesis, biochemical competitions, and metal-dependent activity assays further clarify the functions of the identified amino acid residues in substrate binding or catalysis, respectively. These experiments also reveal that Asp129 form a second-metal binding site, and thus contribute to activity attenuation.

Intrinsic fluorescence from DNA can be enhanced by metallic particles

High sensitivity detection of DNA is essential for genomics. The intrinsic fluorescence from DNA is very weak and almost all methods for detecting DNA rely on the use of extrinsic fluorescent probes. We show that the intrinsic emission from DNA can be enhanced many-fold by spatial proximity to silver island films. Silver islands are subwavelength size patches of metallic silver on an inert substrate. Time-resolved measurements show a decreased lifetime for the intrinsic DNA emission near the silver islands. These results of increased intensity and decreased lifetime indicate a metal-induced increase in the radiative rate decay of the DNA bases. The possibility of increased radiative decay rates for DNA bases and other fluorophores suggest a wide variety of DNA measurements and other biomedical assays based on metal-induced increases in the fluorescence quantum yield of weakly fluorescent substances.

Tegumental alterations in juvenile Schistosoma haematobium harboured in hamsters following artemether treatment

We report the findings of a detailed temporal study on tegumental alterations in juvenile Schistosoma haematobium, induced by artemether, using scanning electron microscopy. Hamsters infected with S. haematobium cercariae for 28 days were treated intragastrically with a single dose of 300 mg/kg artemether. Groups of two hamsters were killed 24 h, 72 h and 7 days after treatment, and schistosomula were recovered from livers by perfusion and subsequent systematic examination of the tissue, before routinely processing for scanning electron microscopic examination. Most schistosomula collected 24 h after artemether administration showed severe tegumental damage, usually including swelling, fusion, vesiculation, peeling and collapse of enlarged sensory structures. After 72 h, tegumental damage had increased and schistosomula generally showed contraction with extensive swelling, erosion and peeling of the tegument. Seven days post-treatment, severe tegumental damage was only seen in a single male specimen with swelling of the worm body and destruction of the oral sucker. The other schistosomula showed only light to moderate damage, suggesting that schistosomula surviving the treatment began to recover. Our findings of tegumental damage following artemether treatment correlate with the efficacy of this novel antischistosomal drug in killing the juvenile stages of S. haematobium and complement recent findings with S. japonicum and S. mansoni.

Association and contribution of ERK to IL-6-induced activation of signal transducer and activator of transcription in a human myeloma cell line

OBJECTIVE

To investigate the regulation effect of protein kinase ERK on the activation of transcription factor STAT3 in response to IL-6 in the Sko-007 human myeloma cell line.

METHODS

Electrophoretic mobility shift assay (EMSA) and immunoprecipitation (IP) were used to show the activation of STAT3 and ERK in Sko-007 cells in the presence and absence of IL-6. Antisense oligonucloetides of ERK (ERK-AS) were transfected into Sko-007 cells to specifically inhibit the expression and activity of ERK. The changes in the activation of STAT3 in the transfected cells were also exhibited by EMSA. Direct binding between STAT3 and ERK was analyzed by co-IP.

RESULTS

Both STAT3 and ERK were activated in Sko-007 cells stimulated with IL-6. ERK-AS inhibited STAT3 activation by IL-6. Moreover, activated ERK could form a complex with STAT3 in Sko-007 cells.

CONCLUSION

ERK can bind STAT3 directly and be required for its maximal activation in Sko-007 cells stimulated by IL-6.

Ocular albinism type 1: more than meets the eye

Ocular albinism type 1 (OA1) is an X-linked recessive disorder characterized by a severe reduction of visual acuity, and hypopigmentation of the retina that leads to nystagmus, strabismus, and photophobia/photodysphoria. Microscopic examination of both retinal pigment epithelium and skin melanocytes in OA1 reveals the presence of macrome-lanosomes, suggesting that the OA1 gene product plays a role in melanosome biogenesis. Studies of mutations identified from OA1 patients and an Oa1 knock-out mouse model further implicate OA1 protein function in the late stage of melanosome development. Because its effects are primarily limited to the eye, OA1 represents an ideal model system to study the relationship between pigmentation and visual development. Based upon sequence homology and biochemical studies, OA1 may represent a novel intracellular G-protein coupled receptor. Understanding the function of OA1 will contribute greatly to our understanding of melanosome biogenesis and the role of pigmentation in visual development.

Endoscopic and histologic evaluation together with symptom assessment are required to diagnose pouchitis

BACKGROUND & AIMS

Pouchitis often is diagnosed based on symptoms alone. In this study, we evaluate whether symptoms correlate with endoscopic and histologic findings in patients with ulcerative colitis and an ileal pouch-anal anastomosis.

METHODS

Symptoms, endoscopy, and histology were assessed in 46 patients using Pouchitis Disease Activity Index (PDAI). Patients were classified as either having pouchitis (PDAI score > or =7; N = 22) or as not having pouchitis (PDAI score <7; N = 24).

RESULTS

Patients with pouchitis had significantly higher mean total PDAI scores, symptom scores, endoscopy scores, and histology scores. There was a similar magnitude of contribution of each component score to the total PDAI for the pouchitis group. Of note, 25% of patients with symptoms suggestive of pouchitis did not meet the PDAI diagnostic criteria for pouchitis. In both groups, the correlation coefficients between symptom, endoscopy, and histology scores were near zero (range, -0.26 to 0.20; P > 0.05).

CONCLUSIONS

The symptom, endoscopy, and histology scores each contribute to the PDAI and appear to be independent of each other. Symptoms alone do not reliably diagnose pouchitis.

Attempt to adsorb N-nitrosamines in solution by use of zeolites

The strong adsorption of zeolite for N-nitrosamines in solution was first revealed by use of adsorption, and temperature programmed surface reaction (TPSR) techniques. N-nitrosodimethylamine (NDMA) and N-nitrosopyrrolidine (NPYR) as well as N-nitrosohexamethyleneimine (NHMI) can be adsorbed on zeolite Y, ZSM-5 and A in the solution of methylene chloride or water, which will be helpful for removal of the N-nitrosamines pollution in environmental protection. The equilibrium data were fitted to Freundlich-type isotherms, but the adsorption capacity of zeolites mainly depended on their pore size, surface area and acid-basic properties. Molecular size of adsorbate and solute-solvent interaction also strongly affected the adsorption of N-nitrosamines on zeolite in solution. The extraordinary adsorption properties of NaA zeolite for N-nitrosamines in aqueous solution is first reported and discussed.