The genetic control of IgA activity against Teladorsagia circumcincta and its association with parasite resistance in naturally infected sheep

Previous studies in deliberately infected sheep have shown an association between IgA activity against 4th-stage larvae of Teladorsagia circumcincta and parasite growth, development and fecundity. The purpose of this research was to determine if these results could be confirmed in naturally infected sheep and to explore the hypothesis that plasma IgA activity could help to identify resistant lambs with shorter adult nematodes. Plasma IgA activity was skewed with most animals having relatively low levels of IgA activity. Plasma IgA activity was repeatable and highly heritable. Animals with increased IgA activity had lower egg counts and shorter adult female T. circumcincta. Therefore, under conditions of natural parasite challenge, plasma IgA activity may help to identify lambs resistant to T. circumcincta.

Errors in data on hospital ownership

In recent years, there has been increased public concern about changes in hospital ownership and consolidation in the hospital market. Numerous studies have examined the relationship between hospital ownership and prices, costs, organization, service mix, access to care and quality of care. However, the data on which these studies are based are often incomplete and inaccurate. In this paper, we examine several sources of data employed by researchers examining hospital ownership and discuss the degree of inaccuracy we found in each source. Substantial primary data collection is necessary to accurately account for changes in ownership and system affiliation.

Principles of molecular microbiology testing methods

Molecular testing methods have the potential to replace many conventional microbiology laboratory assays. Recent refinements in technology have resulted in more user-friendly testing platforms. These platforms are automated and have lowered risks for contamination, decreased costs, and are faster than older platforms. The success of these technologies depends on their successful application to patient care. Quality issues include appropriate specimens for analysis, performance characteristics of different analytical methods, optimal specimen processing, the effects of PCR inhibitors, and false-positive results caused by contaminating nucleic acids. Quality control guidelines for molecular microbiologic diagnostic assays are in their infancy and require further development. Additionally, the problem of "too much" sensitivity (brought on by the extreme sensitivity of these techniques coupled with the potential presence of small numbers of pathogenic organisms in asymptomatic individuals) should be considered. Potential problems when monitoring therapy (because molecular detection techniques do not generally have the ability to determine whether an organism is dead or alive) can also occur. Cost-effective test use, pathogen- or disease-targeted algorithms, and standardized methods will be necessary for the true value of these technologies to be realized. This is especially important, because, unlike traditional culture methods, most molecular microbiology methods are pathogen-specific. Clinicians familiar with the reasons why "pan-culture" (i.e., requesting all culture possibilities at once) is inadvisable should not use the same irrational approach when requesting molecular tests. The clinical usefulness of molecular testing will be maximized as targeted algorithms are developed and an understanding of molecular test ordering patterns is realized. Laboratory technicians and physicians must continue to apply and combine theories of traditional microbiology, clinical chemistry, and general medicine to the understanding and application of molecular diagnostics.

Direct measurements of colloidal friction coefficients

The time-independent hydrodynamic forces operating between two hard spheres were studied as a function of the interparticle separation r. Two colloids were positioned a distance r apart using a dual-beam optical tweezer similar to that described by Meiners and Quake [Phys. Rev. Lett. 82, 2211 (1999)]. Brownian fluctuations in the positions of the two spheres were followed by recording the intensity of forward scattered laser light. The two particles move cooperatively as a result of hydrodynamic forces. The strength of the correlation increased strongly with decreasing separation r. We show that the temporal and spatial correlations in the particle displacements are determined by the distance dependence of the pair friction tensor xi. The distance and geometry dependence of the measured friction tensor is found to be in excellent agreement with the predictions of low-Reynolds number calculations.

Use of a structured investigative protocol enhances young children's responses to free-recall prompts in the course of forensic interviews

One hundred alleged victims of child sexual abuse (ages 4-12 years; M = 8.1 years) were interviewed by police investigators about their alleged experiences. Half of the children were interviewed using the National Institute of Child Health and Human Development's structured interview protocol, whereas the other children--matched with respect to their age, relationship with the alleged perpetrator, and seriousness of the alleged offenses--were interviewed using standard interview practices. Protocol-guided interviews elicited more information using open-ended prompts and less information using option-posing and suggestive questions than did standard interviews; there were no age differences in the amount of information provided in response to open-ended invitations. In 89% of the protocol interviews, children made their preliminary allegations in response to open-ended prompts, compared with 36% in the standard interviews.

Microleakage of tetric ceram/excite and Ariston pHc/Ariston liner

PURPOSE

To investigate the microleakage associated with a hybrid resin-based composite, Tetric Ceram, bonded with the single component dentin bonding agent Excite and Ariston pHc bonded with Ariston Liner. Ariston pHc bonded with Excite and Tetric Ceram bonded with Prime and Bond NT were used as controls.

MATERIALS AND METHODS

Twenty-four extracted human premolars and molars were randomly assigned to four groups. Group 1: cavities were bonded with Excite and filled with Tetric Ceram. Group 2: cavities were bonded with Ariston Liner and filled with Ariston pHc. Group 3, control: cavities were bonded with Prime & Bond NT and filled with Tetric Ceram. Group 4, control: cavities were bonded Excite and filled with Ariston pHc. Cavities were cut in both the buccal and lingual surfaces. Half of each preparation was in enamel and the other was in cementum/dentin. The teeth were thermocycled at 15 degrees C for 2 s, 35 degrees C for 28 s and 45 degrees C for 2 s for 5,000 cycles after which the restorations were examined microscopically for leakage using procion brilliant red as a marker. SEM microphotographs were prepared from dye-labeled and non dye-labeled areas to illustrate the micromorphology of the systems.

RESULTS

None of the groups showed microleakage at the enamel margins. All groups showed microleakage at the gingival margins. At the gingival margin there was a significant difference between the groups (Kruskal-Wallis ANOVA, P= 0.1111.). Ariston pHc/Ariston Liner showed significantly lower microleakage scores than the other groups (Dunn's Multiple Comparison test). SEM showed that in non-dye labeled areas, Ariston pHc/Ariston Liner was in close apposition to the deeper dental tissues. The "total etch" technique resulted in a zone of demineralization. Debonding occurred at or near the top of the hybrid layer in >95% of specimens.

The HLA-DR3,DQ2 heterozygous genotype is associated with an accelerated progression of primary sclerosing cholangitis

BACKGROUND

An improvement of prognostic models in primary sclerosing cholangitis (PSC) is needed. In particular, inclusion of prognostic markers that are independent of the disease stage would be advantageous. We investigated whether HLA class II genes associated with PSC are also related to disease progression.

METHODS

The study included 265 PSC patients from five European countries with a median follow-up of 9.1 years. The end-points were death (n = 38) or liver transplantation (n = 52). Thirty patients developed cholangiocarcinoma during follow-up.

RESULTS

The DRB1*03,DQA1*0501, DQB1*02 (i.e. DR3,DQ2) heterozygous genotype was associated with an increased risk of death or liver transplantation (hazard ratio = 1.63; 95% confidence interval (CI) = 1.06-2.52). The presence of a DQ6 encoding haplotype (DQB1*0603 or DQB1*0602) in DR3,DQ2 negative individuals was associated with a reduced risk of death or liver transplantation (hazard ratio = 0.57; 95% CI = 0.36-0.88). There was a trend towards an increased risk of developing cholangiocarcinoma among DR4,DQ8 positive patients, but this did not reach significance (odds ratio = 2.27; 95% CI = 0.78-6.62).

CONCLUSION

The DR3,DQ2 heterozygous genotype is associated with a more rapid progression of PSC, whereas HLA-DQ6 is associated with a retarded disease progression. It is possible that the DR4,DQ8 haplotype is related to cholangiocarcinoma development.

Lipoxins: revelations on resolution

Lipoxins (LXs) are endogenously produced eicosanoids typically generated during cell-cell interactions. In this article, the compelling evidence from in vitro and in vivo model systems that LXs actively promote the resolution of inflammation is reviewed. Of particular interest are indications that stable synthetic analogues of LXs and aspirin-triggered 15-epi-LXs can mimic many of the desirable anti-inflammatory, "pro-resolution" actions of native LXs. Given the enhanced stability and efficacy of these compounds a role as novel anti-inflammatory therapeutics is proposed.

Fructosamine concentration and resistance to natural, predominantly Teladorsagia circumcincta infection

Fructosamine concentrations reflect protein status and because infection with Teladorsagia circumcincta can induce a relative protein deficiency, we examined the usefulness of fructosamine concentrations as markers of the intensity of infection in naturally infected lambs. Fructosamine concentration was a heritable trait and variation in fructosamine concerntrations was associated with differences in body weight, and a variety of parasitological variables; animals with increased fructosamine concentrations grew more quickly, had increased faecal egg counts in one of the three study years, had decreased pepsinogen concentrations and decreased IgA activity against 4th-stage larvae of T. circumcincta. Fructosamine concentrations were also associated with variation in the subsequent acquisition of nematodes and in the length of adult female T. circumcincta; lambs with increased fructosamine concentrations had fewer nematodes but the mean length of adult female T. circumcincta was longer. Therefore fructosamine concentrations are potentially useful indicators of the severity of nematode infection and may predict magnitude of subsequent infection.

A functional polymorphism of the stromelysin gene (MMP-3) influences susceptibility to primary sclerosing cholangitis

BACKGROUND AND AIMS

We have investigated the influence of a biallelic polymorphism of the promoter region of stromelysin (matrix metalloproteinase 3) on susceptibility to primary sclerosing cholangitis (PSC). The 5A allele is associated with increased transcription, compared with wild-type (6A).

METHODS

An allelic association study was performed: in stage 1, 52 PSC patients (43 with inflammatory bowel disease [IBD]) and 99 healthy subjects (HS) were genotyped. In stage 2, 59 PSC patients (49 IBD), 84 patients with uncomplicated ulcerative colitis, and 72 HS were genotyped.

RESULTS

In stage 1, 5A carriage rate (90.4% vs. 72.7%; P = 0.012) and 5A allelic frequency (65.4% vs. 48.5%; P = 0.005) were increased, and 6A homozygosity was reduced in PSC (9.6% vs. 27.3%; P = 0.012). In stage 2, 5A allelic carriage was increased in PSC (93.2% vs. 76.4% in HS; P = 0.0092) and 6A homozygosity was reduced (6.8% vs. 23.8% in HS; P = 0.0092). Portal hypertension was associated with 5A homozygosity in PSC (P = 0.035; odds ratio [OR], 3.88). In the combined data set, 5A allelic frequencies (63.5% vs. 49.4%; P = 0.001; OR, 1.78) and 5A carriage rates (91.9% vs. 74.2%; P = 0.0002; OR, 3.92) were increased, and 6A homozygosity was reduced in PSC (8.1% vs. 25.7%; P = 0.0002; OR, 0.25). Overall, portal hypertension was associated with 5A homozygosity (P = 0.0192; OR, 3.12).

CONCLUSIONS

Stromelysin polymorphism may influence susceptibility and disease progression in PSC.

Human perceptions of sports equipment under playing conditions

Assessment of the 'performance' of sports equipment is generally derived from physical and technical parameters, such as power, speed, distance and accuracy. However, from a psychological perspective, players need to feel comfortable with their equipment and confident in its properties. These factors can only be measured through the subjective assessment of individual perceptions. Focusing on a group of elite golfers, this study presents a formalized approach for eliciting and structuring players' descriptions of their perception of sports equipment. Qualitative methods of inquiry were used to generate perceptions from a group of professional golfers (n = 15) during play testing. The equipment characteristics of significance to the golfers emerged from an inductive analysis of their responses. However, although this method of representation of the results helped to identify the key components or dimensions of a player's subjective perception, it was unable to determine potential relationships between the dimensions. With this in mind, a new technique, called 'structured relationship modelling', was developed. Ten general dimensions emerged from the analysis, of which three are presented here together with a section of the relationship model. The results demonstrate the effectiveness of qualitative techniques for eliciting human perceptions and of structured relationship models for representation of the associations found.

Effect of composite resin placement techniques on the microleakage of two self-etching dentin-bonding agents

PURPOSE

To evaluate microleakage of Class V resin-based composites (RBC) bonded with two self-etching dentin adhesive systems. Class V cavities were restored with either one or three increments of RBC to determine whether the restorative method affected microleakage.

MATERIALS AND METHODS

60 extracted human premolars and molars were randomly assigned to 6 groups for bonding with Clearfil Liner Bond 2V or Etch & Prime 3.0 or Prime & Bond NT. The latter, using a total-etch technique, was used as a control. Cavities were cut in both the buccal and lingual surfaces. Half of each preparation was in enamel and half was in cementum/dentin. The teeth were thermocycled and the restorations examined microscopically for leakage using Procion Brilliant Red as a marker. SEM microphotographs were prepared from dye-labeled and non dye-labeled areas to illustrate the micromorphology of the systems.

RESULTS

None of the groups showed microleakage at the enamel margins. All groups showed microleakage at the gingival margins. At the gingival margin, there was no significant difference between the groups irrespective of the bonding material (Kruskal-Wallis: ANOVA P=0.2113). No significant difference was observed with each material when the bulk filling (one increment) technique was compared with the three-increment technique. SEM showed that the self-etching materials produced a shallower depth of etch, and a less abundant resin tag complex than the material using a separate phosphoric acid gel. In dye-labeled areas, debonding was predominantly cohesive in resin.

CLINICAL SIGNIFICANCE

Gingival margin microleakage is not prevented by either restoring cavities with self-etching materials of the control using a total-etch technique.

Clinical evaluation of Prime & Bond 2.1 for treating cervical dentin hypersensitivity

PURPOSE

To evaluate the effectiveness of a "one-bottle" dentin adhesive for reducing or eliminating hypersensitivity in exposed cervical dentin.

MATERIALS AND METHODS

Eight patients with hypersensitive teeth were enrolled in this clinical trial. The hypersensitive teeth included a total of 22 premolars and anterior teeth with exposed cervical dentin that was sensitive to cold or other stimuli. A single layer of Prime & Bond 2.1, an acetone-based "one-bottle" adhesive, was applied to the cervical dentin and was light-cured. Sensitivity to compressed air and cold stimuli was determined immediately before and after treatment, and at periods ranging to 24 wks after treatment. Patient responses to the stimuli were timed, and were also evaluated by the use of a visual analogue scale.

RESULTS

Application of a single coat of Prime & Bond 2.1 significantly reduced cervical dentin hypersensitivity to both compressed air and cold stimuli immediately after treatment. The reduction in hypersensitivity remained significant at 24 wks after treatment.

The influence of relative resistance and urea-supplementation on deliberate infection with Teladorsagia circumcincta during winter

The consequences for lambs of infection over the winter with Teladorsagia circumcincta were quantified by deliberate, trickle infection of selected animals at 7 months of age. Infected and control uninfected animals were each allocated into four groups, relatively resistant animals on a normal diet, relatively resistant animals on an isocaloric diet supplemented with urea, and relatively susceptible animals on the same two diets. Resistance and susceptibility was assessed by faecal egg counts following natural infection during the summer preceding the deliberate infection. During the deliberate infection egg counts remained low and most parasites recovered at necropsy were inhibited larvae. Nonetheless, infection reduced weight gain, decreased albumin and fructosamine concentrations and provoked a noticeable pepsinogen and eosinophil response. As most larvae were inhibited these responses may have been largely a consequence of immuno-inflammatory responses in the host rather than the direct action of parasites themselves. Relatively resistant animals on the supplemented diet allowed fewer larvae to establish and had higher fructosamine concentrations, higher albumin concentrations and decreased pepsinogen responses. Therefore, a combination of relatively resistant sheep and nutritional supplementation appears most efficient at controlling infection.

Contractile behavior of smooth muscle actin-containing osteoblasts in collagen-GAG matrices in vitro: implant-related cell contraction

The contraction of connective tissue cells may facilitate their production and maintenance of extracellular matrix architecture and can benefit healing through wound closure. However, aberrant cell contraction can result in pathological contracture. Implants may stimulate this process leading to contracture of the surrounding fibrous capsule. In the case of compliant porous matrices used for tissue engineering the cell contraction may cause the constriction of pores and the distortion of the implant. The objective of this study was to determine if osteoblasts expressed a specific muscle actin, alpha-smooth muscle actin (SMA), that could provide for their contraction. Immunohistochemistry revealed the presence of SMA in some cells in all of three human and three canine trabecular bone specimens. The majority of the cells of an osteoblastic cell line, MC3T3-E 1, also expressed this actin isoform in two-dimensional culture and when seeded into a collagen-glycosaminoglycan (GAG) matrix. These SMA-containing cells were found to cause contraction of the collagen-GAG analog of extracellular matrix. These findings demonstrate that osteoblasts can display contractile behavior that might help to explain the mechanism by which they impart architecture to bone matrix, including that at implant interfaces. An understanding of this process could also guide the development of matrices for bone tissue engineering.

Recurrent blastomycosis of the central nervous system: case report and review

Although blastomycosis of the central nervous system (CNS) occurs in approximately 4% of patients with blastomycosis, recurrent CNS blastomycosis is very rare. We review the clinical features, treatment, and outcome of 4 previously reported cases. We also report a case of recurrent CNS blastomycosis successfully treated with surgery and liposomal amphotericin B after an inadequate response to amphotericin B therapy. This treatment may be an alternate approach for management of similar cases.

Phenotypic and genotypic characterization of commonly used human prostatic cell lines

OBJECTIVE

To investigate and catalogue systematically the phenotypic and genotypic characteristics of the commonly used prostatic cell lines using immunocytochemistry and polymerase chain reaction (PCR) of hypervariable sequences within the genome to provide a 'fingerprint' characteristic of each cell line. Materials and methods Malignant (LNCaP, LNCaP-r, PC-3, DU-145) and benign immortalized prostatic cell lines (PNT-1A, PNT-1B, BPH-1) were grown on four-well slides, fixed and subjected to indirect streptavidin-biotin immunocytochemistry. Twenty-three antibodies were used in the following groups: cytoskeletal elements: cytokeratins (CK)-5, -7, -8, -14 (two), -16, -18, -19 (three), -20, vimentin and desmin; MUC1 (three); cell adhesion molecules (E-cadherin, alpha-beta-and gamma-catenin); and prostatic associated proteins: prostate specific antigen (PSA), prostatic acid phosphatase (PAP) and androgen receptor (AR). For the PCR, genomic DNA was extracted from the cell lines and from SKOV3 and MCF7 (positive controls). PCR was performed on three variable regions which were then sequenced: AR exon 1 (CAG repeat polymorphism), and two areas of microsatellite instability (MSI): AR exon 8 and hypoxanthine-guanine phosphoribosyl transferase (HPRT) exon 3.

RESULTS

All cell lines were CK-8/18 positive and most also expressed CK-7 and -19. Heterogeneous CK-20 expression was detected for the first time in prostatic cell lines. All lines were positive for vimentin and negative for desmin. MUC1 was expressed in one malignant (DU-145) and all immortalized cell lines. E-cadherin expression was low or absent in three lines: PNT1A, 1B and PC-3. Only PC-3 failed to express alpha-catenin; beta- and gamma-catenin were expressed by all lines. PSA, PAP and AR were only expressed by LNCaP and LNCaP-r. On PCR, the CAG repeat lengths in exon 1 of the AR ranged from 19 to 27. Three pairs of cell lines had the same exon 1 CAG repeat length: LNCaP/PC-3 (26 repeats), BPH-1/DU-145 (19 repeats) and PNT1 A/1B (20 repeats). Exon 8 sequences were identical except for LNCaP, which showed a single base mutation, and HPRT exon 3 sequences were all identical. There was no evidence of generalized MSI in any of the cell lines examined.

CONCLUSIONS

The cell lines studied fell into three broad groups according to their phenotypic characteristics: (i) prostatic marker positive (LNCaP and LNCaP-r); (ii) high expression of most antigens (DU-145, PC-3 and BPH-1); and (iii) low or absent expression of most antigens (PNT1 A and 1B). Each of the cell lines derived from PC could be identified on the basis of exon 1 and 8 AR sequence variability. DU145 and BPH-1 had identical profiles of the three areas studied, but these cell lines are easily distinguished by their different phenotypic characteristics. PNT1A and 1B had identical genetic and similar phenotypic profiles, which is unsurprising given that they are subclones derived from the same parental line. Even so, these were separable on the basis of CK-19 immunostaining. Using a combination of geno- and phenotypic markers it was possible to derive a 'fingerprint' for each of the cell lines assessed, which will allow meaningful comparison between similar cell lines held in other laboratories.

Marginal leakage of filled dentin adhesives used with wet and dry bonding techniques

PURPOSE

To evaluate the effect of wet and dry bonding on microleakage of Class V restorations bonded with three filled bonding agents.

MATERIALS AND METHODS

Sixty extracted human premolar and molar teeth were randomly assigned to five groups for bonding with OptiBond Solo, PermaQuick PQI, Prime & Bond NT (one coat), Prime & Bond NT (two coats) and Prime & Bond 2.1, as a control material. Cavities were cut in both the buccal and lingual surfaces. Half of each preparation was in enamel and the other was in cementum/dentin. The cavities were restored with resin-based composite after the application of dentin bonding agents using a wet and dry technique for each material. The teeth were stored in distilled water for 6 days at 37 degrees C, thermocycled, and the restorations examined microscopically for leakage using Procion Brilliant Red as a marker.

RESULTS

All groups showed microleakage at both the enamel and dentin margins. At the gingival margin, there was a significant difference between the groups for wet bonding (P = 0.0349) but not for dry bonding (P = 0.9983) (Kruskal-Wallis test). There was no significant difference between the groups at the enamel margin (wet bonding: P = 0.9999, dry-bonding: P = 0.9304) (Kruskal-Wallis test). The wet-bonding technique was compared with the dry-bonding technique for each material at both the gingival and enamel margins and no significant differences were observed (in all cases P > 0.5) (Mann-Whitney U-test).

An evaluation of peer-led STD/HIV prevention work in a public sex environment

This paper describes an independent evaluation of a peer-led STD/HIV prevention intervention conducted by Gay Men Fighting AIDS (GMFA) in a public sex environment (PSE). A variety of quantitative and qualitative research methods were employed to collect data on the intervention process as well as its outcomes. The main aim of the intervention was the distribution of condoms and safer sex literature to PSE users. During a five-month period, over 100,000 condoms and 2,200 safer sex information packs were distributed by GMFA volunteers to the PSE users. Condom provision was identified as the most needed health promotion activity in PSEs in a survey of gay and bisexual men (n = 688) conducted by the evaluators. Data collected showed that condoms provided by GMFA, as well as from other sources, were being used in the PSE. The peer-led focus of the intervention was acceptable to the PSE users. In addition, high levels of commitment and input from the volunteers contributed considerable added value to the intervention. The evaluation found that GMFA was successful in reaching the target population and addressing their needs and demands.

The influence of age on the variation among sheep in susceptibility to natural nematode infection

A longitudinal study of faecal nematode egg counts was made in naturally infected Scottish Blackface sheep over two grazing seasons to 75 weeks of age. Although egg counts were lower in the second grazing season the variation among animals was greater. Egg counts were repeatable from 3 months of age. The repeatability of faecal egg counts within and between grazing seasons was about 0.3. Animals with lower than average egg counts in the first grazing season tended to have lower than average egg counts in the second grazing season. Therefore lambs with relatively low faecal egg counts after 3 months of age are likely to retain their advantage in the following year.

Human 3'-phosphoadenosine 5'-phosphosulfate synthetase 1 (PAPSS1) and PAPSS2: gene cloning, characterization and chromosomal localization

Sulfae conjugation is an important pathway in the metabolism of a large number of exogenous and endogenous compounds. These reactions are catalyzed by sulfotransferase (SULT) enzymes that utilize 3'-phosphoadenosine 5'-phosphosulfate (PAPS) as a sulfate donor. PAPS is synthesized from ATP and inorganic sulfate by PAPS synthetase (PAPSS). Two separate PAPSS cDNAs, PAPSS1 and PAPSS2, have been identified in human tissues. We have cloned and characterized the genes for human PAPSS1 and PAPSS2 to make it possible to study the pharmacogenomics of these enzymes. Both genes consisted of 12 exons with virtually identical exon-intron splice junction locations. All splice junctions conformed to the "GT-AG" rule. The total length of PAPSS1 was approximately 108 kb, while that of PAPSS2 was greater than 37 kb. The 5'-flanking region of PAPSS1 did not include a TATA box sequence near the site of transcription initiation, but PAPSS2 had a TATA motif located 21 bp upstream from the site of transcription initiation. Northern blot analysis showed that the major PAPSS1 and PAPSS2 transcripts were approximately 2.7 and 4.2 kb in length, respectively. PAPSS1 mapped to human chromosome band 4q24 while PAPSS2 mapped to 10q22-23 by fluorescence in situ hybridization analysis. Cloning and structural characterization of PAPSS1 and PAPSS2 will make it possible to perform molecular genetic and pharmacogenomic studies of these important enzymes in humans.