pH-sensitive cationic polymer gene delivery vehicle: N-Ac-poly(L-histidine)-graft-poly(L-lysine) comb shaped polymer

Advancing biotechnology spurs the development of new pharmaceutically engineered gene delivery vehicles. Poly(L-histidine) ¿PLH¿ has been shown to induce membrane fusion at endosomal pH values, whereas PLL has a well documented efficacy in polyplex formation. Therefore, N-Ac-poly(L-histidine)-graft-poly(L-lysine) ¿PLH-g-PLL¿ was synthesized by grafting poly(L-histidine) to poly(L-lysine) ¿PLL¿. PLH-g-PLL formed polyplex particles by electrostatic interactions with plasmid DNA ¿pDNA¿. The mean particle size of the polyplexes was in the range of 117 +/- 6 nm to 306 +/- 77 nm. PLH-g-PLL gene carrier demonstrated higher transfection efficacy in 293T cells than PLL at all equivalent weight ratios with pDNA. The inclusion of chloroquine as an endosomolytic agent enhanced transfection for both PLL and PLH-g-PLL gene carriers. PLH-g-PLL enhanced beta-galactosidase expression compared to PLL, but still increased in efficacy when chloroquine was included.

Conformation and function of the N-linked glycan in the adhesion domain of human CD2

The adhesion domain of human CD2 bears a single N-linked carbohydrate. The solution structure of a fragment of CD2 containing the covalently bound high-mannose N-glycan [-(N-acetylglucosamine)2-(mannose)5-8] was solved by nuclear magnetic resonance. The stem and two of three branches of the carbohydrate structure are well defined and the mobility of proximal glycan residues is restricted. Mutagenesis of all residues in the vicinity of the glycan suggests that the glycan is not a component of the CD2-CD58 interface; rather, the carbohydrate stabilizes the protein fold by counterbalancing an unfavorable clustering of five positive charges centered about lysine-61 of CD2.

Complementarity of ecological goal functions

This paper summarizes, in the framework of network environ analysis, a set of analyses of energy-matter flow and storage in steady-state systems. The network perspective is used to codify and unify ten ecological orientors or extremal principles: maximum power (Lotka), maximum storage (Jørgensen-Mejer), maximum empower and emergy (Odum), maximum ascendency (Ulanowicz), maximum dissipation (Schneider-Kay), maximum cycling (Morowitz), maximum residence time (Cheslak-Lamarra), minimum specific dissipation (Onsager, Prigogine), and minimum empower to exergy ratio (Bastianoni-Marchettini). We show that, seen in this framework, these seemingly disparate extrema are all mutually consistent, suggesting a common pattern for ecosystem development. This pattern unfolds in the network organization of systems.

Effect of sodium chloride on the gelation temperature, gel strength and bioadhesive force of poloxamer gels containing diclofenac sodium

Liquid suppository systems composed of poloxamers and bioadhesive polymers were easy to administer to the anus and mucoadhesive to the rectal tissues without leakage after the dose. However, a liquid suppository system containing diclofenac sodium could not be developed using bioadhesive polymers, since the drug was precipitated in this preparation. To develop a liquid suppository system using sodium chloride instead of bioadhesive polymers, the physicochemical properties such as gelation temperature, gel strength and bioadhesive force of various formulations composed of diclofenac sodium, poloxamers and sodium chloride were investigated. The mixtures of P 407 (15%) and P 188 (15-20%) existed as a liquid at room temperature, but gelled at physiological temperature. Diclofenac sodium significantly increased the gelation temperature and weakened the gel strength and bioadhesive force, while sodium chloride did the opposite. Furthermore, the poloxamer gels with less than 1.0% of sodium chloride, in which the drug was not precipitated, were inserted into the rectum of rabbits without difficulty and leakage, and retained in the rectum of rats for at least 6 h. Our results suggested that a thermosensitive liquid suppository system with sodium chloride and poloxamers was a more physically stable and convenient rectal dosage form for diclofenac sodium.

Antioxidant flavonoids and chlorogenic acid from the leaves of Eriobotrya japonica

The antioxidant activity of Eriobotrya japonica was determined by measuring the radical scavenging effect on DPPH (1,1-diphenyl-2-picrylhydrazyl) radical and lipid peroxidation produced when mouse liver homogenate was exposed to the air at 37 degrees C, using 2-thiobarbituric acid (TBA). The methanol extract and its fractions of Eriobotrya japonica leaves showed strong antioxidant activity. The antioxidant activity of EtOAc and n-BuOH soluble fractions were stronger than the others, and were further purified by repeated silica gel, MCl gel CHP-20P, and Sephadex LH-20 column chromatography. Antioxidant chlorogenic acid, quercetin-3-sambubioside from n-BuOH fraction, and methyl chlorogenate, kaempferol- and quercetin-3-rhamnosides, together with the inactive ursolic acid and 2 alpha-hydroxyursolic acid from EtOAc fraction were isolated. Antioxidant flavonoids and chlorogenic acid also showed prominent inhibitory activity against free radical generation in dichlorofluorescein (DCF) method.

Poly(ethylene glycol)-block-poly(L-lysine) dendrimer: novel linear polymer/dendrimer block copolymer forming a spherical water-soluble polyionic complex with DNA

Methoxypoly(ethylene glycol)-block-poly(L-lysine) dendrimer was designed to form a water-soluble complex with plasmid DNA. The copolymer was synthesized by the liquid-phase peptide synthesis method. It was characterized by 1H NMR and matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectrum. Agarose gel electrophoresis and DNase I protection assay proved that this linear polymer/dendrimer block copolymer assembled spontaneously with plasmid DNA, forming a water-soluble complex which increased the stability of the complexed DNA. Atomic force microscopy of the complex was evaluated at various charge ratios showing that the copolymer/DNA complex was like a globular shape.

A novel angiogenic factor derived from Aloe vera gel: beta-sitosterol, a plant sterol

Aloe vera gel has a beneficial effect on wound healing. Because angiogenesis is an essential process in wound healing, we hypothesized that Aloe vera gel might contain potent angiogenic compounds. Here we demonstrate that Aloe vera gel and its extracts are angiogenic on the chorioallantoic membrane (CAM) of chick embryo. Out of the three compounds purified from the final fraction of Aloe vera gel, beta-sitosterol showed a potent angiogenic activity in the CAM assay. In the presence of heparin, beta-sitosterol stimulated neovascularization in the mouse Matrigel plug assay and the motility of human umbilical vein endothelial cells in an in vitro wound migration assay. Thus beta-sitosterol is a novel plant-derived angiogenic factor which may have potential pharmaceutical applications for the management of chronic wounds.

In vitro activation of pro-phenol-oxidase by two kinds of pro-phenol-oxidase-activating factors isolated from hemolymph of coleopteran, Holotrichia diomphalia larvae

Previously, we purified and characterized a pro-phenol-oxidase (pro-PO) of 79 kDa from coleopteran insect, Holotrichia diomphalia larvae [Kwon et al. (1997) Mol. Cells 7, 90-97]. Here, we describe the identification of two pro-PO-activating factors (PPAF), named PPAF-I and PPAF-II, directly involved in the activation of the isolated pro-PO. When pro-PO was incubated with either PPAF-I or PPAF-II, no phenol oxidase activity was observed. However, incubation of pro-PO with both PPAF-I and PPAF-II specifically exhibited phenol oxidase activity. The purified PPAF-I with a molecular mass of 33 kDa on SDS/PAGE had characteristics of a serine protease. It exhibited amidase activity against fluorogenic peptide substrates, tert-butoxycarbonyl-phenylalanyl-seryl-arginyl-4-methylcoumaryl-7-amide being the best among the substrates examined. The activity was completely inhibited by 0.02 mM p-nitrophenyl-p'-guanidinobenzoate HCl and diisopropylflurophosphate. The NH2-terminal sequence of PPAF-I had significant sequence similarity to those of serine proteases. On the other hand, the purified PPAF-II had a molecular mass of 40 kDa on SDS/PAGE and 400 kDa determined by gel filtration, indicating an oligomeric protein. The NH2-terminal sequence of PPAF-II showed no similarity to known proteins. PPAF-II exhibited no amidase activity against the fluorogenic substrates. Reconstitution experiments and immunoblotting analysis using affinity-purified antibody against pro-PO demonstrated that PPAF-I first cleaves the intact pro-PO to an intermediate of 76 kDa with no phenol oxidase activity, and then, PPAF-I converts the intermediate to the active phenol oxidase of 60 kDa in the presence of PPAF-II. These results indicate that the activation of pro-PO system in hemolymph of H. diomphalia larvae is accomplished by at least two activating factors, a serine protease and a protein cofactor.

Epidemiologic and clinical survey of Behcet's disease in Korea: the first multicenter study

The prevalence of Behcet's disease is the highest in the East Asian and the Mediterranean countries. Behcet's disease is also distributed in the Asian countries, but the nationwide survey has not been performed in Korea yet. The Korean Study Group for Behcet's Disease, founded in 1999, conducted a multicenter, retrospective survey on epidemiologic and clinical features of the patients with Behcet's disease from 20 hospitals around the nation from 1997 to 1999. Of 3,497 patients, 1,527 were classified into complete or incomplete type of Behcet's disease according to the revised Shimizu's classification. The sex ratio was 1:1.75 with the female predominance. Geographical distribution showed the highest frequency in Seoul (38.5%). Clinically, 98.8% had oral ulcers, 83.2% had genital ulcers, 84.3% had skin lesions and 50.9% had ocular lesions. As for the minor clinical manifestations, articular symptoms were the most frequent. The pathergy test showed positive in 15.4% of patients and revealed a higher positive rate in males (20.2%) than in females (12.7%). In conclusion, we performed the first multicenter study on Behcet's disease in Korea and revealed the female predominance, higher frequency of ocular lesions, and lower positivity of pathergy test in the patients.

Two hevein homologs isolated from the seed of Pharbitis nil L. exhibit potent antifungal activity

Two antifungal peptides (Pn-AMP1 and Pn-AMP2) have been purified to homogeneity from seeds of Pharbitis nil. The amino acid sequences of Pn-AMP1 (41 amino acid0 residues) and Pn-AMP2 (40 amino acid residues) were identical except that Pn-AMP1 has an additional serine residue at the carboxyl-terminus. The molecular masses of Pn-AMP1 and Pn-AMP2 were confirmed as 4299.7 and 4213.2 Da, respectively. Both the Pn-AMPs were highly basic (pI 12.02) and had characteristics of cysteine/glycine rich chitin-binding domain. Pn-AMPs exhibited potent antifungal activity against both chitin-containing and non-chitin-containing fungi in the cell wall. Concentrations required for 50% inhibition of fungal growth were ranged from 3 to 26 micrograms/ml for Pn-AMP1 and from 0.6 to 75 micrograms/ml for Pn-AMP2. The Pn-AMPs penetrated very rapidly into fungal hyphae and localized at septum and hyphal tips of fungi, which caused burst of hyphal tips. Burst of hyphae resulted in disruption of the fungal membrane and leakage of the cytoplasmic materials. To our knowledge, Pn-AMPs are the first hevein-like proteins that show similar fungicidal effects as thionins do.

New cationic liposomes for gene transfer into mammalian cells with high efficiency and low toxicity

Novel cationic amphiphiles, based on hydrophobic cholesterol linked to L-lysinamide or L-ornithinamide, were designed and tested as nonviral gene transfer vectors. Each amide form of amino acid was conjugated to cholesterol by a carbamate ester bond to facilitate efficient degradation in animal cells. Cytotoxicity tests were performed for some cell lines. The transfection efficiency of the amphiphiles on different cell lines was evaluated as a liposomal solution in the presence of the fusogenic helper lipid, dioleoyl phosphatidylethanolamine (DOPE). The efficiency was also compared with other generally used gene carriers, such as lipofectin, 3 beta[N-(N'N'-dimethylaminoethane)-carbamoyl] cholesterol (DC-Chol) liposome, and polyethylenimine (PEI).

Expression of vascular endothelial growth factor and inducible nitric oxide synthase in pterygia

PURPOSE

To evaluate the expression of vascular endothelial growth factor (VEGF) in pterygium and investigate the interrelationships between VEGF and nitric oxide (NO) in the development of pterygia.

METHODS

Specimens of normal conjunctiva acquired incidentally to conjunctival transplantation during pterygium and strabismus surgery and the excised pterygium were used in this study. Cryopreserved tissue specimens consisting of normal conjunctiva and pterygium were used to study the expression of VEGF and inducible NO synthetase (iNOS), using immunohistochemistry. For confirmation of NOS activity, reduced nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase staining was done. Enzyme-linked immunosorbent assay (ELISA) for detection and quantification of VEGF was performed.

RESULTS

Expression of VEGF and iNOS was strongly revealed mainly in the epithelium of the head portions of pterygial specimens, although not in the epithelium of conjunctival ones. Pterygial epithelium was stained with NADPH diaphorase, confirming NOS activity. ELISA showed a greater amount of VEGF in pterygium (11.7 +/- 2.1 pg/mg) compared with normal conjunctiva (4 +/- 0.47 pg/mg) ( p < 0.05).

CONCLUSION

These data are the first to demonstrate that VEGF and NO may play an important role in the development of pterygium and to identify VEGF and NO in the epithelium of pterygium. We hypothesize that environmental stress, such as ultraviolet irradiation and local inflammation stimulate the elaboration of NO and VEGF, resulting in the conjunctival fibrovascular ingrowth characteristic of pterygium.

Gastrointestinal stromal tumors in Koreans: it's incidence and the clinical, pathologic and immunohistochemical findings

Seven hundred forty seven cases of gastrointestinal stromal tumors (GISTs) in Koreans who were diagnosed between 2001 and 2002 were analyzed to evaluate their occurrence and their clinical, pathologic and immunohistochemical findings. The most frequent location of tumor was in the stomach (63%), followed by the small intestine (30%), the colorectum (5%), and the esophagus (2%). c-kit expression was found in 93.6% of the cases, while CD34, SMA and S-100 protein was positive in 80.1%, 28.2%, and 20.2%, respectively. c-kit positivity was high in the stomach (94.2%) and small intestine (94.6%), while it was relatively low in the colorectum (85.0%), and esophagus (81.2%). The positivity for CD34 was correlated with the higher risk of GISTs (p = 0.04). Follow up of the patients showed that 58 primary GISTs patients died and 20 of these patients were recurrent or metastatic at the time of diagnosis. The pathologic diagnosis to predict the risk of aggressive behavior of GISTs was correlated with the numbers of tumor, clinical stage, epithelioid histologic type, cellularity, cellular atypia, necrosis, and mucosal invasion (p = 0.00). GISTs with a poor prognosis were closely related to the clinical stage at presentation, the locations of the tumor, and the ages of the patients.

Multiple gastrointestinal stromal tumors: Clinicopathologic and genetic analysis of 12 patients

Multiple gastrointestinal stromal tumors (GISTs) are extremely rare and usually associated with type 1 neurofibromatosis and familial GIST. The aim of this study was to investigate the clinical, phenotypic, and genetic characteristics of multiple GISTs to gain insights into their underlying pathogenesis and clinical behavior. Forty-seven paraffin blocks of multiple GISTs from 12 patients were analyzed. Genomic DNA was extracted from the tumor and normal mucosa and mutations for 4 exons of KIT gene and 3 exons of PDGFRA gene were determined. Among 12 patients with multiple GISTs, 5 were sporadic, 2 were familial with germline mutations of KIT gene, and 5 were associated with type 1 neurofibromatosis. All but 1 sporadic and familial multiple GISTs showed mutations of KIT gene shared by the same mutation on each GIST mass within a patient. But in 1 sporadic case, different types of KIT mutations were observed. Two familial multiple GIST cases showed diffuse involvement of the gastrointestinal tract with diffuse hyperplasia of interstitial cell of Cajal. Multiple GISTs associated with type 1 neurofibromatosis were located in the jejunum and harbored no mutations of KIT or PDGFRA. Different types of KIT gene mutation found in our case raise a possibility that recurrence of GISTs within a gastrointestinal tract may have a chance to be a rare occurrence of multiple primary GISTs instead of true recurrence. Multiple GISTs show unique clinical, phenotypic, and genotypic characteristics that are dependent on the particular underlying mechanisms, but the overall prognosis is favorable regardless of the numbers or phenotype of GISTs.

Characterization of a targeted gene carrier, lactose-polyethylene glycol-grafted poly-L-lysine and its complex with plasmid DNA

The physicochemical properties and gene transfer ability of lactose-polyethylene glycol-grafted poly-L-lysine (Lac-PEG-PLL) were investigated. A dye displacement assay showed that plasmid DNA self-assembled with Lac-PEG-PLL, and condensation began at a <1:1 charge ratio of plasmid DNA to polymer. In atomic force microscopy, spontaneously assembled Lac-PEG-PLL/DNA complexes revealed a compact structure, with a size of about 100-200 nm. Circular dichroism spectra of Lac-PEG-PLL/DNA complexes revealed that the secondary structure of DNA was altered by complex formation and was similar to that of the poly-L-lysine/DNA complex. Lac-PEG-PLL was shown to protect DNA against nuclease action in a DNase I protection assay. The cytotoxicity test demonstrated that the complex composed of plasmid DNA and Lac-PEG-PLL had little influence on the viability of HepG2 cells, especially in comparison with that of poly-L-lysine/DNA complexes. In conclusion, our copolymer, Lac-PEG-PLI, formed complexes with plasmid DNA (on average, 150 nm), gave little cytotoxicity, and showed increased efficiency of gene transfer into hepatoma cells in vitro. Lactose-polyethylene glycol was grafted to poly-L-lysine to be used as a gene carrier for hepatoma cell targeting and to improve the solubility of the polyplexes. The average size of the carrier/DNA complexes was about 150 nm. The complexes also proved to have high resistance against nuclease attack and little cytotoxicity. The polymer also delivered plasmid DNA efficiently into a HepG2 cell line. Lac-PEG-PLL was more efficient than Lipofectin or galactose-PEG-PLL in transfection efficiency.

Detection of benzo[a]pyrene diol epoxide-DNA adducts in human placenta

Human placenta is a readily available organ that responds to maternal environmental insult and has been previously used to investigate metabolism and bioactivation of procarcinogens, for example, benzo[a]pyrene. HPLC in combination with synchronous fluorescence spectroscopy was used to examine 28 placentas for the presence of benzo[a]pyrene diol epoxide-DNA adducts, and 10 of these were found to be positive. DNA samples from these placentas were subsequently pooled and subjected to partial enzymatic digestion to oligonucleotide fragments. Concentration of those DNA fragments containing benzo[a]pyrene diol epoxide-DNA adducts was achieved by immunoaffinity chromatography with polyclonal antibodies raised against these adducts. Column eluates were hydrolyzed under mild acid conditions and extracted with an organic solvent. The presence of benzo[a]pyrene-7,10/8,9-tetrahydrotetrol residues in the extracts was determined by HPLC and synchronous fluorescence spectroscopy and was confirmed by GC/MS. The results unequivocally confirm bioactivation and formation of DNA adducts from benzo[a]pyrene in human placenta in vivo and establish a methodological approach to direct measurement of carcinogen-DNA adducts that are formed as a result of human environmental exposure.

Antimutagenic effect of plant flavonoids in the Salmonella assay system

The antimutagenic effects of 27 kinds of plant flavonoids on the mutagenicity of aflatoxin B1(AFB1) and N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) in Salmonella typhimurium TA100 were investigated. In the mixed applications of AFB1 (1 microgram/plate) with the flavonoids (300 micrograms/plate) in the presence of a mammalian metabolic activation system (S9 mix), chrysin, apigenin, luteolin and its glucoside, kaempferol, fisetin, morin, naringenin, hesperetin, persicogenin, (+)-catechin and (-)-epicatechin showed the antimutagenic effect against AFB1 with more than 70% inhibition rate. A little or no antimutagenicities except flavone against MNNG (0.5 microgram/plate) were observed. For the antimutagenicity of the flavonoids on AFB1, the flavonoid structure that contains the free 5-, 7-hydroxyl group seemed to be essential. However, saturation of the 2,3-double bond or elimination of the 4-keto group did not affect the activity.

Structure-related inhibition of human hepatic caffeine N3-demethylation by naturally occurring flavonoids

The effects of flavonoids on caffeine N3-demethylation, a marker activity of CYP1A2, in human liver microsomes were investigated to elucidate the inhibition mechanism and the structure-activity relationship. Caffeine N3-demethylase activity was inhibited by the presence of various flavonoids, whose structures seem to be closely related to the degree of inhibition. Among twenty-one compounds tested, the most active was chrysin with an IC50 value of 0.2 microM. Others had IC50 values ranging from 1 to more than 500 microM. Kinetic analysis revealed that the mechanism of inhibition varied among the flavonoids. The inhibitory effect was postulated to be governed by factors such as the number of hydroxyl groups and glycosylation of these free hydroxyl groups. An increase in the number of free hydroxyl groups reduced the inhibitory effect on P450 activity. Analysis of the quantitative structure-activity relationship (QSAR) showed that the volume to surface area ratio was the most effective factor on the inhibition of caffeine N3-demethylation, and the electron densities on the C3 and C4' atoms exercised significant influence on the inhibitory effect. The calculated inhibitory effect of flavonoids on CYP1A2 activity was highly correlated with the antimutagenicity of flavonoids in 2-amino-3,4-dimethylimidazo[4,5-flquinoline (MelQ)-induced umu response.

Derivative fluorescence spectral analysis of polycyclic aromatic hydrocarbon-DNA adducts in human placenta

Metabolic activation in humans of chemical carcinogens found in the environment results in the formation of carcinogen-DNA adducts in vivo. Some polycyclic aromatic hydrocarbon-DNA adducts in human DNA can be hydrolyzed under mildly acidic conditions to yield tetrahydrotetrol derivatives which may then be detected by synchronous fluorescence spectroscopy. In an analysis of human placental DNA, second derivative spectroscopy alone was unable to resolve the synchronous fluorescent signature for r-7,t-8,t-9,c-10-tetrahydroxy-7,8,9,10-tetrahydrobenzo[alpha]pyrene from a crude extract, because a complex array of other fluorescent materials was also present. Purification of the sample by a combination of chromatographic procedures including immunoaffinity chromatography and HPLC has now been shown to yield r-7,t-8,t-9,c-10-tetrahydroxy-7,8,9,10-tetrahydrobenzo[alpha]pyrene residues from human DNA that are spectroscopically pure at the second derivative level. Immunoaffinity columns were prepared with rabbit antiserum raised against DNA that had been modified with (+/-)-r-7,t-8-dihydroxy-t-9,10-epoxy-7,8,9,10-tetrahydrobenzo[alpha]pyre ne. This antiserum has now been shown to recognize DNA samples that have been modified with six different polycyclic aromatic hydrocarbon diol epoxides and is probably only specific for a broad spectrum of polycyclic aromatic hydrocarbon-DNA adducts. Adducts were eluted from the immunoaffinity columns, hydrolyzed with acid, and extracted into isoamyl alcohol, before being subjected to high-performance liquid chromatography. These experiments reveal important limitations of second derivative fluorescence spectroscopy as a tool in the analysis of complex environmental mixtures. Furthermore, they extensively define the ability of anti-benzo[alpha]pyrenediol epoxide-DNA antibodies to recognize different types of polycyclic aromatic hydrocarbon-DNA adducts.

Reproducibility of colonic transit study in patients with chronic constipation

PURPOSE

Major therapeutic decisions are rendered based on a single colonic transit study. Therefore, the aim of this study was to assess the reproducibility of colonic transit time in patients with chronic constipation.

MATERIALS AND METHODS

Fifty-one patients with chronic idiopathic constipation were randomly selected to undergo two separate colonic transit tests. All clinical conditions, methodology, and patients' instructions were identical on both occasions. The gamma rate (linear correlation analysis) was undertaken between the first and second colonic transit times. Groups were divided according to the diagnoses of colonic inertia (slow-transit constipation), paradoxical puborectalis contraction, and chronic idiopathic constipation (normal-transit constipation).

RESULTS

In 35 of 51 patients (69 percent), the results were identical between the two studies; however, in 16 patients (31 percent), the results were disparate (gamma correlation coefficient = 0.53; P < 0.01). The specific correlation coefficients for patients with colonic inertia, paradoxical puborectalis contraction, and chronic idiopathic constipation were 0.12, 0.21, and 0.60 (P < 0.01), respectively. Moreover, the success rate of colectomy for colonic inertia was significantly higher in patients who underwent a repeat transit study confirming inertia than in patients who underwent colectomy based on a single study.

CONCLUSIONS

Overall, colonic transit time is reproducible in patients with chronic constipation. The correlation coefficient is best for patients with idiopathic constipation and worst for patients with colonic inertia. This new finding suggests that suboptimal surgical outcome may be attributable to inaccurate diagnosis. Because of this poor correlation coefficient, in patients with colonic inertia, consideration should be given to repeating the colonic transit study before colectomy to help secure the diagnosis and improve outcome.

Intraobserver and interobserver measurements of the anorectal angle and perineal descent in defecography

PURPOSE

Anorectal angle and perineal descent can be measured either by drawing a line defined by the impression of the puborectalis muscle and the tangential of the posterior rectal wall (Method A) or by drawing a straight line at the level of the posterior rectal wall parallel to the central longitudinal axis of the rectum (Method B). The aim of this study was to assess the reproducibility of measuring anorectal angle and perineal descent by two different methods according to intraobserver and interobserver measurement and to evaluate which method yields more consistent results.

METHODS

Five physicians who have had an average of 1.3 years (range, 6 months to 1.5 years) experience in defecographic measurement drew both lines on 63 randomly selected defecographic films and measured anorectal angle and perineal descent by the two methods. The defecographic parameters were measured twice by each observer during a three-week interval. To avoid potential bias, one physician who did not participate in either measurement of perineal descent or anorectal angle performed all data collection. Intraobserver and interobserver agreement was quantified using Shrout and Fleiss intraclass correlation coefficients.

RESULTS

The mean and range of intraclass correlation coefficients for intraobserver agreement of measuring anorectal angle and perineal descent by Method A were 0.71 (0.6-0.78) and 0.89 (0.74-0.97), respectively, whereas with Method B the coefficients were 0.81 (0.73-0.89) and 0.93 (0.89-0.99), respectively. Regarding the interobserver agreement of the five observers, the mean coefficients for measurement of both anorectal angle and perineal descent by both methods showed similar agreement levels (0.88 and 0.98 by Method A and 0.89 and 0.97 by Method B). The mean (+/- standard deviation) values of anorectal angle and perineal descent found by Method B were significantly larger than those found by Method A (103.3 degrees +/- 19.6 and 6.56+/-3.20 cm and 91.1 degrees +/- 25.6 and 5.64+/-3.42 cm, respectively; P<0.001).

CONCLUSION

Intraobserver and interobserver intraclass correlation coefficients of anorectal angle and perineal descent, which were measured by both methods, were more than 0.60, indicating that both methods are reliable and consistent for measurement of anorectal angle and perineal descent. However, centers should consistently use the same line for measurement of anorectal angle and perineal descent because of the statistically significant differences between the two methods and the possibility of inconsistent results.

Composition and sequence specific resonance assignments of the heterogeneous N-linked glycan in the 13.6 kDa adhesion domain of human CD2 as determined by NMR on the intact glycoprotein

CD2, a T cell specific surface adhesion receptor, is critically important for T lymphocytes to mediate their regulatory and effector functions. The amino terminal domain of human CD2 is responsible for cell adhesion, binding to CD58 on antigen-presenting cells or target cells. This adhesion domain in human CD2 contains a single high-mannose N-glycan. This carbohydrate or part of it appears to be required to maintain the native conformation of the polypeptide and its ability to bind CD58. To better understand the structural aspects that regulate human CD2 adhesion functions, we had previously determined the solution structure of the protein part of the N-glycosylated adhesion domain of human CD2 (hu-sCD2(105); MW approximately 13.6 kDa) by NMR spectroscopy. Here, we have identified protein--carbohydrate and carbohydrate--carbohydrate interactions and, in combination with previous knowledge from electrospray ionization mass spectrometry, have determined the composition of the heterogeneous high-mannose glycan in hu-sCD2(105). These contacts clearly define the carbohydrate's orientation with respect to the protein. The NMR data further suggest that one arm of the glycan is folded toward the trisaccharide core consisting of GlcNAc1-GlcNAc2-Man3. A detailed comparison between chemical shift data of free model oligosaccharides with those of the glycomers present in our hu-sCD2(105) sample reveals that only the resonances of the two GlcNAc residues are significantly different from those of free high-mannose glycans. This work was based on a new strategy to achieve sequential assignments of the 1H and 13C resonances of the heterogeneous high-mannose carbohydrate [(Man)nGlcNAc2, n = 5-8] in hu-sCD2(105) on the intact glycoprotein using a combination of homonuclear 1H-1H and heteronuclear 1H-13C NMR experiments at natural abundance.

Isolation of luteolin 7-O-rutinoside and esculetin with potential antioxidant activity from the aerial parts of Artemisia montana

The antioxidant activity of Artemisia montana was determined by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and inhibitory activity against free radical generation of hepatocytes (AC2F). The methanol extract of A. montana showed strong radical scavenging activity at a concentration of 10.1 microg/ml, and thus fractionated by solvent extraction. Esculetin and luteolin 7-O-rutinoside (scolymoside) were isolated as the active principles from the EtOAc and Interphase fractions, respectively. The antioxidant activity of these compounds were comparable to that of L-ascorbic acid.

Accuracy and reproducibility of telecytology diagnosis of cervical smears. A tool for quality assurance programs

We randomly selected 50 cervical smears (benign, 14; atypical squamous cells of undetermined significance [ASCUS], 5; low-grade squamous intraepithelial lesion [LSIL], 10; high-grade squamous intraepithelial lesion (HSIL), 12; squamous cell carcinoma, 6; adenocarcinoma, 3) and captured 1,181 digital images (518 MB) at a maximum resolution of 1,600 x 1,200 pixels and transmitted them by e-mail. Diagnosis of glass slides and digital images was done independently in a double-blind manner by 3 pathologists and 3 cytotechnologists, commencing with the diagnosis of digital images followed by diagnosis of glass slides 3 months later. The procedure was repeated after 3 months. Diagnoses were recorded as benign, ASCUS or atypical glandular cells of undetermined significance, LSIL, HSIL, squamous cell carcinoma or adenocarcinoma, and "inadequate for diagnosis." Diagnostic accuracy and interobserver reproducibility were analyzed using an intraclass correlation coefficient (ICC), which revealed good interobserver agreement for the first (0.72) and second (0.64) glass slide diagnoses and the first (0.72) and second (0.60) digital image diagnoses. The kappa values for intraobserver variation between first and second glass slide diagnoses and first and second digital image diagnoses showed moderate to excellent agreement. Digital images are suitable substitutes for glass slides; telecytology can be used as an alternative method for the cytologic diagnosis of cervical smears, particularly in quality assurance programs.

Outcome and management of patients with large rectoanal intussusception

OBJECTIVES

Rectoanal intussusception is the funnel-shaped infolding of the rectum, which occurs during evacuation. The aims of this study were to evaluate the risk of full thickness rectal prolapse during follow-up of patients with large rectoanal intussusception, and whether therapy improved functional outcome.

METHODS

Between September 1988 and July 1997, patients diagnosed with a large rectoanal intussusception by cinedefecography (intussusception > or = 10 mm, extending into the anal canal) were retrospectively evaluated. Patients with full thickness rectal prolapse on physical examination or cinedefecography were excluded, as were patients with colonic inertia or a history of surgery for rectal prolapse. The patients were divided into three groups according to the treatment received: group I, conservative dietary therapy; group II, biofeedback; and group III, surgery. Outcomes were obtained by postal questionnaires or telephone interviews. Parameters included age, gender, past medical and surgical history, change of bowel habits, fecal incontinence score, and development of full thickness rectal prolapse.

RESULTS

Of the 63 patients, 18 were excluded (seven patients had confirmed full thickness rectal prolapse, four had previous surgery for rectal prolapse, three had colonic inertia, and four died). Follow-up data were obtained in 36 (80%) of the remaining 45 patients. The mean follow-up of this group was 45 months (range, 12-118 months). There were 34 women and two men, with a mean age of 72.4 yr (range, 37-91 yr). The mean size of the intussusception was 2.2 cm (range, 1.0-5.0 cm). The patients were classified as follows: group I, 13 patients (36.1%); group II, 13 patients (36.1%); and group III, 10 patients (27.8%). Subjectively, symptoms improved in five (38.5%), four (30.8%), and six (60.0%) patients in the three groups (p > 0.05). Among the patients with constipation, the decrease in numbers of assisted bowel movements per week (time of diagnosis to present) was significantly greater in group II compared to group 1 (8.1+/-2.8 vs 0.8+/-0.5, respectively, p = 0.004). Among the patients with incontinence, incontinence scores improved more in group II as compared to either group I or group III (time of diagnosis to present, 3.7+/-4.2 to 1.1+/-5.4 vs 1.4+/-2.2, respectively, p > 0.05). Six patients (two in group I, three in group II, and one in group III) had the sensation of rectal prolapse on evacuation; however, only one patient in group I developed full thickness rectal prolapse.

CONCLUSIONS

This study demonstrated that the risk of full thickness rectal prolapse developing in patients medically treated for large intussusception is very small (1/26, 3.8%). Moreover, biofeedback is beneficial to improve the symptoms of both constipation and incontinence in these patients. Therefore, biofeedback should be considered as the initial therapy of choice for large rectoanal intussusception.