bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cytotoxic effect of autocrine and macrophage-derived nitric oxide on cultured rat mesangial cells
Authors: Hruby Z , Beck K-F 
Published: November 2003

Abstract
Expression of the inducible form of nitric oxide synthase (iNOS) has been found to be up-regulated in cytokine-stimulated mesangial cells (MC) and in experimental glomerulonephritis. Since direct toxicity of nitric oxide (NO) has been implicated in damage of bacteria, neoplastic and intact pancreatic cells, we investigated whether NO is cytotoxic to cultured MC, which may be relevant to pathogenesis of glomerular injury. MC isolated from rat glomeruli generated substantial amounts of nitrite, the stable NO end-product, when cells were stimulated with IL-1β and tumour necrosis factor-alpha (TNF-α). Total DNA synthesis was significantly reduced in the presence of IL-1β and TNF-α, and this effect was completely reversed by NG-monomethyl-l-arginine (l-NMMA), an inhibitor of iNOS. Stimulation of MC with IL-1β and TNF-α caused remarkable toxicity to these cells, measured by the MTT test (3-(4,5-dimethylthiazol-2-yl)2,5-diphenyl tetrazolium bromide cleavage, specific cytotoxicity 41.5 ± 20.3%), and much less prominent MC lysis (3H-thymidine release, specific cytolysis 11.5 ± 5.3%). Toxic effects of cytokines were fully reversible by the iNOS inhibitor. Lipopolysaccharide (LPS) and interferon-gamma (IFN-γ), but not IL-1β and TNF-α, induced rat peritoneal macrophages to produce large amounts of nitrite. In co-culture, such prestimulated macrophages had significantly cytotoxic (MTT test 62.9 ± 19.9%) and cytolytic (3H-thymidine release 57.9 ± 13.8%)effects on MC. Again, this toxicity was totally inhibited in the presence of l-NMMA. We conclude from these results that cytokine-stimulated generation of NO by MC or macrophages is directly toxic to MC, and may play a role in pathogenesis of glomerular injury involving mesangiolysis.
Novel autoantigens of perinuclear anti-neutrophil cytoplasmic antibodies (P-ANCA) in ulcerative colitis: non-histone chromosomal proteins, HMG1 and HMG2
Authors: Sobajima J , Ozaki S , Osakada F , Uesugi H , Shirakawa H , Yoshida M , Nakao K 
Published: November 2003

Abstract
Anti-neutrophil cytoplasmic antibodies (ANCA) in sera from ulcerative colitis (UC) patients have been described as reacting with proteins in the granules of human neutrophils such as cathepsin G and lactoferrin and with yet unidentified antigens. Here we report the existence of a new member of perinuclear ANCA (P-ANCA) in UC patients. In the previous study, we found that UC patients had a novel P-ANCA against neutrophil 28-kD protein. In this study, we purified the same antigens from HL-60 lysates by using reversed phase high-performance liquid chromatography, and revealed that the 28-kD antigen consisted of two different proteins. The N-terminus amino acids of these proteins are identical with those of high mobility group (HMG) non-histone chromosomal proteins HMG1 and HMG2. Immunoblotting analysis of human neutrophil lysates using rabbit anti-HMG1/2 antisera revealed a single band of 28 kD, and the 28-kD band detected by immunoblotting analysis using patient's serum IgG completely disappeared after preincubation with a mixture of HMG1 and HMG2. Furthermore, rabbit anti-HMG1/2 antisera showed a perinuclear staining pattern in indirect immunofluorescence studies using ethanol-fixed neutrophils. These data demonstrate that HMG1 and HMG2 are novel target antigens of P-ANCA. HMG1 and HMG2 are distributed in the nuclei and cytoplasm of eukaryotic cells and act as transcription factors. Their intracellular localization and functions are distinct from those of the previously reported granular antigens of P-ANCA.
Functional integrity of granulosa cells from polycystic ovaries
Authors: Almahbobi Ghanim , Anderiesz Cleola , Hutchinson Paul , McFarlane James R. , Wood Carl , Trounson Alan O. 
Published: November 2003

OBJECTIVE The polycystic ovarian syndrome is frequently associated with human infertility and is a partially characterized syndrome of unknown aetiology. The aim of this study was to describe the functional integrity of granulosa cells from polycystic ovaries.PATIENTS Follicular aspirates were collected from polycystic ovaries of ovulatory (n = 24) and anovulatory (n = 7) patients. Follicular aspirates were also collected from normal ovaries of untreated (n = 24) and superovulated (n = 10) subjects. All patients were enrolled for the recovery of their oocytes for in vitro maturation and fertilization.MEASUREMENTS FSH receptors and apoptosis were measured in the granulosa cells of the different patients. FSH‐stimulated oestradiol and LH‐stimulated progesterone production by granulosa cells of the different patients were also measured.RESULTS The binding of 125I‐labelled human recombinant FSH to granulosa cells from anovulatory subjects with polycystic ovaries was significantly higher than that found in granulosa cells from normal (180%) and superovulated (163%) ovaries. However, the ligand binding to granulosa cells from ovulatory subjects with polycystic ovaries was not significantly higher than that found in normal granulosa cells. Also, granulosa cells obtained from anovulatory subjects with polycystic ovaries cultured with FSH produced more oestradiol than normal granulosa cells but oestradiol production was similar to that of granulosa cells from superovulated ovaries (mean ± SEM, 244.94 ± 22.02, 24.23 ± 2.92, 211.87 ± 50.39 nmol/l/24 h, respectively). Flow cytometric analysis showed that the proportions of viable and apoptotic granulosa cells (mean ± SDM, 70 ± 5 and 7 ± 1%, respectively) were similar in normal subjects and in those with polycystic ovaries.CONCLUSION We conclude that most of the granulosa cells of polycystic ovaries are healthy and non‐apoptotic, expressing high levels of FSH receptors and highly responsive to this hormone in culture. These data provide direct evidence that most of the follicles of polycystic ovaries are not atretic.
Position‐dependent reproductive success of flowers in Dactylorhiza maculata (Orchidaceae)
Authors: Vallius E. 
Published: November 2003

Abstract1. This study explores the importance of flower position for reproductive success of individual flowers of the deceptive terrestrial orchid, Dactylorhiza maculata (L.) Soó.2. Upper flowers had smaller lips and produced lighter pollinia than those in other parts of the inflorescence, probably due to architectural effects.3. Dry weight of seed capsules decreased from bottom to top in the inflorescence in both open‐pollinated and hand‐pollinated plants. However, removal of flowers from the middle and lowest parts of the inflorescence considerably increased seed production of the upper flowers. Decreased seed set was due to decreased resource availability because of the long maintenance time of opened but not pollinated lower flowers.4. Experimental self‐pollination resulted in reduced seed set compared to that following pollination with cross‐pollen, but decreased seed set was independent of flower position within an inflorescence.5.  Dactylorhiza maculata with large inflorescences did not have better pollination success. The production of more flowers than the plant is able to fully support may have evolved as an ovary reserve in case of flower herbivory, or as a ‘bet‐hedging’ strategy through which the plant can increase seed production in years with good pollinator availability.
Do endogenous seasonal cycles of food intake influence foraging behaviour and intake by grazing sheep?
Authors: Iason G. R. , Sim D. A. , Gordon I. J. 
Published: November 2003

Abstract1. Large herbivores living in temperate regions show different degrees of seasonal biological variation, including voluntary food intake (VFI). The decline of VFI in winter has been hypothesized to be an evolved response to lower food availability or quality, which can act as an internal constraint on food intake.2. The hypotheses were tested that (i) animals that have a greater inherent seasonal variation of VFI, measured indoors under ad libitum conditions, would also have a greater seasonal variation in intake and grazing behaviour under field conditions, and (ii) greater seasonal variation in intake and grazing behaviour under field conditions would be expressed at a higher level of food availability.3. The intake and grazing behaviour in summer and winter, of three breeds of sheep, were compared at two levels of food availability (at pasture heights of 3·7 and 5·4 cm). The breeds were known to have contrasting degrees of seasonal variation in food intake when fed ad libitum; the VFI of the Shetland (SH) and Scottish Blackface (BF) sheep varies greatly between seasons whereas that of the Dorset Horn (DH) is less seasonally variable.4. All three breeds consistently increased their rates of biting and duration of grazing activity in the winter, taking many more smaller bites each day than in the summer, and both digestibility and intake were lower in winter than in summer.5. Contrary to expectation, the DH ewes had the highest seasonal difference of dry matter intake at pasture, whereas the SH breed had the lowest variation of intake between seasons.6. This experiment provides no evidence that differences between seasons in intake and foraging behaviour in the field vary with the animals’ degree of endogenous seasonal variation in VFI. Variation between seasons was consistent at both levels of resource availability, suggesting that it resulted from seasonal changes in food quality (digestibility) rather than biomass availability. It is not easy to extrapolate from laboratory feeding studies, where animals’ own physiological constraints apply, to foraging ecology in the field, where constraints imposed by the environment may be more important.
HsMCM6: a new member of the human MCM/P1 family encodes a protein homologous to fission yeast Mis5
Authors: Tsuruga Hiromichi , Yabuta Norikazu , Hosoya Shiki , Tamura Kazutoshi , Endo Yuichi , Nojima Hiroshi 
Published: November 2003

Background:The tight regulatory mechanism that prevents more than one round of chromosomal DNA replication per cell cycle is thought to require the function of Mcm/P1 proteins. We report here the structural and functional analyses of HsMcm6, a human homologue of the Mis5 of Schizosaccharomyces pombe.Results:We demonstrate here that the transcription of the HsMCM6 gene was repressed in quiescent cells but was rapidly induced at the G1/S phase by growth factor stimulation. The 5′ regulatory region of the HsMCM6 gene was found to harbour four putative E2F binding motifs, and these were responsible for the promoter activity. The HsMcm6 protein level oscillated during the cell cycle, with a peak at the G1/S phase. We also showed that the cell‐cycle dependent change of subcellular localization of HsMcm6 resembles those of other Mcm/P1 proteins. HsMcm6 consists of two forms, a form extractable by Nonidet P‐40 and the nucleus‐bound form. A demonstration of the association of HsMcm6 with HsMcm2 and HsMcm7 in vivo supports the idea that they behave as a heteromeric complex. We mapped the HsMCM6 gene at 2q12–14.Conclusion:The results indicate that the behaviour of HsMcm6 is reminiscent of replication licensing factor like other Mcm/P1 family members.
DAP‐1, a novel protein that interacts with the guanylate kinase‐like domains of hDLG and PSD‐95
Authors: Satoh Kiyotoshi , Yanai Hiroyuki , Senda Takao , Kohu Kazuyoshi , Nakamura Tsutomu , Okumura Nobuaki , Matsumine Akihiko , Kobayashi Shigeru , Toyoshima Kumao , Akiyama Tetsu 
Published: November 2003

Background:The human homologue of the Drosophila discs large tumour suppressor protein (hDLG) and closely related proteins such as postsynaptic density protein 95 kDa (PSD‐95) are associated with N‐methyl‐d‐aspartate receptors (NMDA‐R) and Shaker‐type K+ channels, and are thought to be involved in their clustering.Results:We have identified a protein named DAP‐1 that binds to the guanylate kinase‐like domains of hDLG and PSD‐95. DAP‐1 was found to associate with hDLG, PSD‐95, NMDA‐R and adenomatous polyposis coli protein (APC). Furthermore, we found that DAP‐1 is specifically expressed in the brain and colocalizes with PSD‐95 and APC in mouse cerebellum. We also found that DAP‐1 is colocalized with PSD‐95 and NMDA‐R at the synapses in cultured rat hippocampal neurons.Conclusion:Our findings suggest that DAP‐1 may play several roles in the molecular organization of synapses and neuronal cell signalling by interacting with hDLG and PSD‐95, which in turn are associated with receptors, ion channels and APC.
Saccharomyces cerevisiae recA homologues RAD51 and DMC1 have both distinct and overlapping roles in meiotic recombination
Authors: Shinohara Akira , Gasior Stephen , Ogawa Tomoko , Kleckner Nancy , Bishop Douglas K. 
Published: November 2003

Background:Rad51 and Dmc1 are Saccharomyces cerevisiae homologues of the Escherichia coli recombination protein RecA. Mutant analysis has shown that both proteins are required for normal meiotic recombination, for timely and efficient formation of synaptonemal complex and for normal progression out from meiotic prophase.Results:We have further characterized rad51 and dmc1 single mutants. A dmc1 mutation confers more severe defects in double strand break (DSB) resolution, crossover recombination and meiotic progression than does a rad51 mutant; in contrast, during return to growth, a rad51 mutation confers more severe defects in viability and intrachromosomal recombination than does a dmc1 mutation. Analysis of a rad51 dmc1 double mutant, in parallel with single mutants, shows that the double mutant is more defective with respect to the formation of crossovers during meiosis and, especially strikingly, with respect to interhomologue and intrachromosomal recombination during return to growth. Consistent with the observation of DMC1‐dependent recombination in a rad51 mutant, subnuclear complexes of Dmc1 protein were detected for the first time in this mutant. In contrast to the effects on recombination, the effect of the double mutant on meiotic progression was similar to that of the rad51 single mutant.Conclusion:Rad51 and Dmc1 each make unique contributions to meiotic recombination. However, the two proteins are capable of substituting for one another under some circumstances, implying that they most likely share at least one recombination function. Recombination and cell cycle phenotypes are all consistent with the possibility that a dmc1 mutation causes an arrest of the post‐DSB recombination complexes at a later, more stable stage than does a rad51 mutation.
Return to work following laparoscopic hysterectomy
Authors: Rosen D. M. B. , Cario G. M. , Carlton M. A. , Lam A. M. 
Published: November 2003

ObjectiveTo determine an accurate figure for the time of expected return to work or normal activity following a laparoscopic hysterectomy.DesignA telephone survey of 100 patients who had undergone laparoscopic hysterectomy between September 1994 and July 1996.ResultsThe mean time for return to work or normal activity was 3.3 weeks. Amongst those who worked, this figure was reduced to 2.9 weeks. Patients also reported that they could have returned to work at 2.3 weeks on average. These differences were statistically significant. There was also a significant difference between the recovery times of those reporting some complication and those who did not.ConclusionThis study allows the surgeon to confidently advise patients of expected recovery times following laparoscopic hysterectomy. It also highlights the benefits of preoperative counselling, both in terms of patient motivation to recover and in terms of forewarning of minor complications and the effect of such complications on recovery time and therefore patient satisfaction.
Skin chemical suture using Histoacryl in laparoscopic surgery
Authors: Ghirardini G. , Battioni M. , Radighieri G. 
Published: November 2003

ObjectiveTo verify whether the use of Histoacryl tissue adhesive could replace skin suture of abdominal wounds in laparoscopy.DesignHistoacryl was used to repair abdominal wounds in 60 consecutive cases of diagnostic or operative laparoscopy.ResultsThe procedure was successful in 59 of the 60 cases.ConclusionsOur data suggest that this method reduces the time needed for suture, and shows better aesthetic results and patient acceptance.
The effect of sterilization on bending and torsional properties of K‐files manufactured with different metallic alloys
Authors: Canalda‐Sahli C. , Brau‐Aguadé E. , Sentís‐Vilalta J. 
Published: November 2003

The purpose of this study was to assess the effect of dry‐heat or autoclave sterilization on the resistance to fracture in torque and angular deflection and the resistance to bending of K‐type files made of nickel‐titanium (Nitiflex, Naviflex), titanium (Microtitane) or stainless steel (Flexofile, Flex‐R).Ten K‐type files of each sort, from size 25 to 40, were tested, according to ANSI/ADA specification 28 (1988) and ISO specification 3630 (1992). Sterilization with dry heat and autoclave slightly decreased the flexibility of files made of stainless steel and nickel‐titanium for most of the sizes, although the values obtained satisfied ISO specifications. The files made of titanium showed an increased flexibility after sterilization with autoclave (sizes 30 and 35) and dry heat (sizes 30, 35 and 40). Resistance to fracture varied amongst the five groups of files tested as follows: it decreased in some sizes of stainless‐steel instruments, decreased in all sizes of titanium files assessed by the torsional moment, and either increased or decreased in some sizes of nickel‐titanium files. All files tested, however, satisfied relevant standards for angular deflection after being subjected to sterilization with an autoclave or dry heat.
Comparison of two endodontic handpieces during the preparation of root canals in extracted human teeth
Authors: Smith R. B. , Edmunds D. H. 
Published: November 2003

This in vitro study compared and assessed two endodontic handpieces during the preparation of root canals in extracted human teeth. Eighty extracted human teeth, with single root canals, were divided into eight matched groups. They were prepared using Shaper files activated by the MM1500 Sonic Air handpiece (Micro‐Mega, Besançon, France) or Excalibur files activated by the W & H Excalibur 969 handpiece (W & H, Bürmoos, Austria). The files were 21 mm or 25 mm in length. When preparing the canals, the files were used either in line with or perpendicular to any canal curvature. Preparation of the canals was carried out using the techniques described in the manufacturers' literature. A variety of parameters were used to compare the hand‐pieces, including canal preparation time, deformation or fracture of instruments, loss of canal length, weight loss from the prepared teeth and the overall postpreparation canal shape. A microradiographic technique was used to produce a tracing record of the pre‐ and postpreparation canal shape. Both handpieces provided an efficient and easy method of preparing and shaping the root canal with little operator fatigue. The MM1500 Sonic air handpiece took significantly more time (P <0.001) to prepare the canals than the Excalibur.Few aberrations in the shapes of prepared canals were created by either handpiece. No endodontic file fractured but a few of them were permanently deformed. The effects of two variables — file length and the plane of use of the file — on performance of the handpieces, were also assessed.
Evaluation of characterization methods for thin sections of silver halide microcrystals by analytical electron microscopy
Authors: GREGORY C. , GIJBELS R. , JACOB W. , GEUENS I. , VAN ROOST C. , DE KEYZER R. 
Published: November 2003

Silver halide microcrystals are usually composed of different phases with varying halide compositions. These microcrystals can be sectioned with an ultramicrotome with a certain thickness in a specific direction. The scanning electron microscopical analysis of these sections provides information on the internal halide profile.During sample sectioning, many deformations can be induced in the material, and usually dominate the different scanning electron images.By acquiring X‐ray maps, it is possible to locate the different phases in the sections. This technique, however, is very time‐consuming, and can only be used when the local halide variations are very high.When an EDX line scan is acquired over the section, information on the position of the phases with different halide composition is obtained in a reasonable time, and shows no dependence on the section deformations. From this knowledge, several positions on the section are selected where local X‐ray analyses are performed. After quantifying the results, the internal halide distribution is obtained. The analytical lateral resolution is about 30 nm for sections ≈100 nm thick.
Scanning tunnelling microscopy imaging of [3 × 3] Mn nonanuclear grids
Authors: Weeks L. , Thompson L. K. , Shapter J. G. , Pope K. J. , Xu Z. 
Published: November 2003

SummaryThe scanning tunnelling microscopy imaging of [3 × 3] Mn(II) nonanuclear grids on gold substrates is described. Self‐assembled behaviour is observed at both high and low coverage, with submolecular resolution of individual molecules displayed at low deposition concentrations. The importance of proper image processing techniques is demonstrated in resolving the layer structure at high coverage.
A simple method to ‘point count’ silt using scanning electron microscopy aided by image analysis
Authors: Ware C. I. 
Published: November 2003

SummaryThis study presents a simple method to ‘point count’ silt‐sized grains using backscattered scanning electron microscopy together with image analysis. The work materialized out of the need to determine the heavy mineral abundance within silt obtained from coastal dunes to aid in the interpretation of dune weathering. This technique allows two broad mineral groups to be quantified according to their modal abundance. The groups are characterized by their dominant atomic elements present; atomic numbers > 20 are classified as ‘high’ (metal oxides, zircon, monazite, carbonates, pyroxenes and amphiboles) and those < 20 as ‘low’ (quartz, feldspars and organics). As a check on this technique, X‐ray fluorescence was used. This showed a strong positive correlation (r2 = 0.85) with the developed point counting technique.
Three‐dimensional visualization of insect morphology using confocal laser scanning microscopy
Authors: Klaus A. V. , Kulasekera V. L. , Schawaroch V. 
Published: November 2003

SummaryCuticular structures of insects are often microscopic and intricately complex; among the most complex structures are male genitalia. Genitalic structures are essential in taxonomic and phylogenetic studies of insects. Using well‐described species from two disparate dipteran genera, we demonstrate the utility of confocal laser scanning microscopy for studying the morphological characters of fly genitalia by taking advantage of the autofluorescent properties of cuticle material. Reconstructions of confocal data sets obtained from genitalic structures embedded in two commonly used entomological mounting media (euparal and glycerin jelly) are presented. Aberration artefacts often observed in confocal data obtained from thick specimens were analysed and strategies for their minimization are discussed. Our results indicate that confocal laser scanning microscopy and 3D reconstruction are excellent techniques for visualizing small, complex, autofluorescent structures in flies. These techniques could have a profound impact on the quality of information provided by 3D representations of insect structures over more traditional methods of visualization.